'use strict';

const fs = require('fs');
const path = require('path');
const { arrowRingsAt, normalizeManeuver } = require('./turn-lane-arrows');
const { buildComplexJunctionGeometry, complexJunctionMetrics } = require('./complex-junction');

const OVERRIDE_SCHEMA = 'native-road-overrides/v1';
const MOTOR_HIGHWAYS = new Set([
  'motorway',
  'trunk',
  'primary',
  'secondary',
  'tertiary',
  'unclassified',
  'residential',
  'living_street',
  'service',
]);
const DEFAULT_WIDTHS = {
  motorway: 12,
  trunk: 10,
  primary: 10,
  secondary: 8,
  tertiary: 7,
  unclassified: 6,
  residential: 6,
  living_street: 5,
  service: 4,
};
const DEFAULT_SIDEWALK_WIDTH_METERS = 2;
const DIRECTION_ARROW_INTERVAL_METERS = 32;
const DIRECTION_ARROW_ENDPOINT_BUFFER_METERS = 14;
const STOP_LINE_OFFSET_METERS = 2.7;
const STOP_LINE_MAX_APPROACH_DISTANCE_METERS = 25;
const CROSSWALK_JUNCTION_INSET_METERS = 1.5;
const CROSSWALK_MAX_JUNCTION_INSET_METERS = 4;
const CENTER_LINE_DASH_LENGTH_METERS = 2;
const CENTER_LINE_DASH_GAP_METERS = 2;
const CENTER_LINE_WIDTH_METERS = 0.25;
const CENTER_LINE_SOLID_OVERLAP_METERS = 0.04;
const CENTER_LINE_CONTROL_CLEARANCE_METERS = 1;
const CENTER_LINE_COLORS = new Set(['yellow', 'white']);
const CENTER_LINE_PATTERNS = new Set(['dashed', 'solid']);
const CONNECTOR_BOUNDARY_TOLERANCE_METERS = 0.05;
// A lane centerline is drawn as a hairline, so probe the crossing with a narrow
// band. Using the full lane width would clip the line metres early.
const LANE_CENTERLINE_PROBE_WIDTH_METERS = 0.12;
const JUNCTION_CURVE_SEGMENTS = 8;

function parseOsmRoads(xml) {
  const nodes = new Map();
  const crossingNodes = [];
  for (const match of xml.matchAll(/<node\b([^>]*?)(?:\/>|>([\s\S]*?)<\/node>)/g)) {
    const attrs = xmlAttrs(match[1]);
    if (attrs.action === 'delete' || !attrs.id || attrs.lon === undefined || attrs.lat === undefined) continue;
    const coordinate = [Number(attrs.lon), Number(attrs.lat)];
    if (!coordinate.every(Number.isFinite)) continue;
    const id = String(attrs.id);
    const tags = parseTags(match[2] || '');
    nodes.set(id, coordinate);
    if (tags.highway === 'crossing' && !['no', 'none', 'unmarked'].includes(tags['crossing:markings']))
      crossingNodes.push({ id, coordinate, tags });
  }
  const ways = [];
  for (const match of xml.matchAll(/<way\b([^>]*)>([\s\S]*?)<\/way>/g)) {
    const attrs = xmlAttrs(match[1]);
    const body = match[2];
    const tags = parseTags(body);
    if (attrs.action === 'delete' || !MOTOR_HIGHWAYS.has(tags.highway || '')) continue;
    const refs = [...body.matchAll(/<nd\b([^>]*)\/?\s*>/g)].map((item) => xmlAttrs(item[1]).ref).filter(Boolean);
    const coords = refs.map((ref) => nodes.get(String(ref))).filter(Boolean);
    if (coords.length < 2 || coords.length !== refs.length) continue;
    ways.push({ id: String(attrs.id), refs: refs.map(String), coords, tags });
  }
  return { nodes, ways, crossingNodes };
}

function compileRoadModel(xml, overrides) {
  const parsed = parseOsmRoads(xml);
  const diagnostics = [];
  const roads = [];
  const endpoints = [];
  const byNode = new Map();
  const sharedNodeWayIds = new Map();
  for (const way of parsed.ways)
    for (const nodeId of new Set(way.refs)) {
      if (!sharedNodeWayIds.has(nodeId)) sharedNodeWayIds.set(nodeId, new Set());
      sharedNodeWayIds.get(nodeId).add(way.id);
    }
  for (const sourceWay of parsed.ways) {
    const segments = splitWayAtSharedNodes(sourceWay, sharedNodeWayIds);
    for (const way of segments) {
      const directions =
        way.tags.oneway === 'yes' || way.tags.oneway === '1' || way.tags.junction === 'roundabout'
          ? ['forward']
          : ['forward', 'backward'];
      for (const direction of directions) {
        const base = roadAttributes(way.tags, direction);
        const id = `road:way/${way.id}${way.segmentIndex === null ? '' : `:segment/${way.segmentIndex}`}:${direction}`;
        const road = {
          id,
          osmWayIds: [way.id],
          segmentId: `segment:way/${way.id}/${way.segmentIndex ?? 0}`,
          sourceRoadId: `road:way/${way.id}:${direction}`,
          direction,
          highway: way.tags.highway,
          centerline: direction === 'forward' ? way.coords : [...way.coords].reverse(),
          sourceNodeIds: direction === 'forward' ? [way.refs[0], way.refs.at(-1)] : [way.refs.at(-1), way.refs[0]],
          tags: way.tags,
          ...base,
          appliedOverrideIds: [],
          diagnostics: [],
        };
        applyRoadOverrides(road, overrides, diagnostics);
        roads.push(road);
        for (const side of ['start', 'end']) {
          const nodeId = side === 'start' ? road.sourceNodeIds[0] : road.sourceNodeIds[1];
          const endpoint = {
            id: `endpoint:${road.id}:${side}`,
            roadId: id,
            side,
            nodeId,
            coordinate: side === 'start' ? road.centerline[0] : road.centerline.at(-1),
            direction,
          };
          endpoints.push(endpoint);
          if (!byNode.has(nodeId)) byNode.set(nodeId, []);
          byNode.get(nodeId).push(endpoint);
        }
      }
    }
  }
  const connections = resolveConnections(endpoints, byNode, overrides, diagnostics);
  const extent = roadExtent(roads);
  for (const [nodeId, items] of byNode) {
    if (items.length === 1 && distanceToExtentEdgeMeters(items[0].coordinate, extent) > 25) {
      const endpoint = items[0];
      diagnostics.push({
        ...diagnostic(
          'warning',
          endpoint.roadId,
          [nodeId],
          'unconnected-interior-road-end',
          '道路在区域内部结束，未连接到其他机动车道路。请确认这是实际断头，还是 OSM 节点尚未连接。',
          endpoint.coordinate,
        ),
        endpointId: endpoint.id,
        manualCandidates: nearbyManualCandidates(endpoints, endpoint),
      });
    }
  }
  const crossings = parsed.crossingNodes.map((crossing) => ({
    ...crossing,
    osmWayIds: parsed.ways.filter((way) => way.refs.includes(crossing.id)).map((way) => way.id),
  }));
  return { schema: 'native-road-model/v1', roads, endpoints, connections, crossings, diagnostics };
}

function splitWayAtSharedNodes(way, sharedNodeWayIds) {
  const splitIndexes = [0];
  for (let index = 1; index < way.refs.length - 1; index += 1)
    if ((sharedNodeWayIds.get(way.refs[index])?.size || 0) > 1) splitIndexes.push(index);
  splitIndexes.push(way.refs.length - 1);
  if (splitIndexes.length === 2) return [{ ...way, segmentIndex: null }];
  return splitIndexes.slice(1).map((end, index) => {
    const start = splitIndexes[index];
    return {
      ...way,
      refs: way.refs.slice(start, end + 1),
      coords: way.coords.slice(start, end + 1),
      segmentIndex: index + 1,
    };
  });
}

function roadExtent(roads) {
  const points = roads.flatMap((road) => road.centerline);
  return {
    minLon: Math.min(...points.map((point) => point[0])),
    maxLon: Math.max(...points.map((point) => point[0])),
    minLat: Math.min(...points.map((point) => point[1])),
    maxLat: Math.max(...points.map((point) => point[1])),
  };
}

function distanceToExtentEdgeMeters(point, extent) {
  const lonScale = 111320 * Math.cos((point[1] * Math.PI) / 180);
  return Math.min(
    (point[0] - extent.minLon) * lonScale,
    (extent.maxLon - point[0]) * lonScale,
    (point[1] - extent.minLat) * 111320,
    (extent.maxLat - point[1]) * 111320,
  );
}

function roadAttributes(tags, direction) {
  const directional = direction === 'forward' ? 'forward' : 'backward';
  const laneTag = tags[`lanes:${directional}`] ?? (tags.oneway === 'yes' ? tags.lanes : null);
  const parsedLanes = positiveInteger(laneTag);
  const totalLanes = positiveInteger(tags.lanes);
  const lanes = parsedLanes || (totalLanes ? Math.max(1, Math.ceil(totalLanes / (tags.oneway === 'yes' ? 1 : 2))) : 1);
  const parsedWidth = positiveNumber(tags.width);
  const forwardLanes = positiveInteger(tags['lanes:forward']);
  const backwardLanes = positiveInteger(tags['lanes:backward']);
  const directionalLaneTotal = forwardLanes && backwardLanes ? forwardLanes + backwardLanes : totalLanes;
  // `width` describes the whole OSM way. A directional road receives its lane
  // share; absent width falls back to a realistic per-lane carriageway width.
  const width = parsedWidth
    ? (parsedWidth * lanes) / (directionalLaneTotal || (tags.oneway === 'yes' ? lanes : lanes * 2))
    : lanes * 3.25;
  return {
    laneCount: lanes,
    widthMeters: width,
    sidewalkLeft: sidewalkState(tags, direction, 'left'),
    sidewalkRight: sidewalkState(tags, direction, 'right'),
    provenance: {
      laneCount:
        parsedLanes || totalLanes ? `tag:${parsedLanes ? `lanes:${directional}` : 'lanes'}` : 'inferred:default-lanes',
      widthMeters: parsedWidth ? 'tag:width (按方向车道数分配)' : 'inferred:3.25m-per-lane',
    },
  };
}

function sidewalkState(tags, direction, side) {
  const osmSide = direction === 'forward' ? side : side === 'left' ? 'right' : 'left';
  const value = tags[`sidewalk:${osmSide}`] ?? tags.sidewalk;
  return value === 'both' || value === 'yes' || value === osmSide;
}

function loadOverrides(file) {
  if (!fs.existsSync(file)) return { schema: OVERRIDE_SCHEMA, overrides: [] };
  return validateOverrides(JSON.parse(fs.readFileSync(file, 'utf8')));
}

// An override points at an id derived from OSM. Editing the source can retire
// that id — a way deleted, or split differently so `segment/6` no longer
// exists — which leaves the entry pointing at nothing. That is stale data, not
// a malformed override, so callers that merely consume overrides can ask to
// skip them and keep going. Callers that *save* overrides still use the default
// strict mode: writing a reference that cannot resolve is a real error.
function staleOverrideTarget(item, sets) {
  if (!sets.roadIds) return null;
  if (item.kind === 'road' && typeof item.roadId === 'string' && !sets.roadIds.has(item.roadId)) return item.roadId;
  if (item.kind === 'lane-separator-style' && typeof item.roadId === 'string' && !sets.roadIds.has(item.roadId))
    return item.roadId;
  if (item.kind === 'edge-line-style' && typeof item.roadId === 'string' && !sets.directionalRoadIds.has(item.roadId))
    return item.roadId;
  if (item.kind === 'center-line-style' && typeof item.segmentId === 'string' && !sets.segmentIds.has(item.segmentId))
    return item.segmentId;
  if (
    item.kind === 'junction-connection' &&
    typeof item.fromEndpointId === 'string' &&
    typeof item.toEndpointId === 'string' &&
    (!sets.endpointIds.has(item.fromEndpointId) || !sets.endpointIds.has(item.toEndpointId))
  )
    return `${item.fromEndpointId} → ${item.toEndpointId}`;
  if (
    item.kind === 'lane-connection' &&
    typeof item.fromLaneId === 'string' &&
    typeof item.toLaneId === 'string' &&
    (!sets.laneIds.has(item.fromLaneId) || !sets.laneIds.has(item.toLaneId))
  )
    return `${item.fromLaneId} → ${item.toLaneId}`;
  return null;
}

function validateOverrides(value, model, options = {}) {
  if (!value || value.schema !== OVERRIDE_SCHEMA || !Array.isArray(value.overrides))
    throw new Error(`Overrides must use ${OVERRIDE_SCHEMA}.`);
  const ids = new Set();
  const roadIds = model ? new Set(model.roads.flatMap((road) => [road.id, road.sourceRoadId])) : null;
  const directionalRoadIds = model ? new Set(model.roads.map((road) => road.id)) : null;
  const endpointIds = model ? new Set(model.endpoints.map((endpoint) => endpoint.id)) : null;
  const laneIds = model
    ? new Set(
        model.roads.flatMap((road) =>
          Array.from({ length: road.laneCount }, (_, index) => `lane:${road.id}:${index + 1}`),
        ),
      )
    : null;
  const segmentIds = model ? new Set(model.roads.map((road) => road.segmentId)) : null;
  const sets = { roadIds, directionalRoadIds, endpointIds, laneIds, segmentIds };
  const kept = [];
  const stale = [];
  for (const item of value.overrides) {
    if (!item || typeof item.id !== 'string' || !item.id || ids.has(item.id))
      throw new Error('Each override needs a unique id.');
    ids.add(item.id);
    if (options.skipStaleTargets) {
      const target = staleOverrideTarget(item, sets);
      if (target) {
        stale.push({ id: item.id, kind: item.kind, target });
        continue;
      }
    }
    if (item.kind === 'road') {
      if (typeof item.roadId !== 'string' || (roadIds && !roadIds.has(item.roadId)))
        throw new Error(`Unknown road override target: ${item.roadId}`);
      for (const key of ['widthMeters', 'laneCount'])
        if (
          item[key] !== undefined &&
          (!Number.isFinite(item[key]) || item[key] <= 0 || (key === 'laneCount' && !Number.isInteger(item[key])))
        )
          throw new Error(`Invalid road override ${key}.`);
      for (const key of ['sidewalkLeft', 'sidewalkRight'])
        if (item[key] !== undefined && typeof item[key] !== 'boolean') throw new Error(`Invalid road override ${key}.`);
    } else if (item.kind === 'junction-connection') {
      if (
        typeof item.fromEndpointId !== 'string' ||
        typeof item.toEndpointId !== 'string' ||
        typeof item.enabled !== 'boolean' ||
        (endpointIds && (!endpointIds.has(item.fromEndpointId) || !endpointIds.has(item.toEndpointId)))
      )
        throw new Error('Invalid junction connection override.');
      if (model && !connectionEndpointsCompatible(model, item.fromEndpointId, item.toEndpointId))
        throw new Error('A manual junction connection must go from a road end to a nearby road start (within 35m).');
    } else if (item.kind === 'lane-connection') {
      if (
        typeof item.fromLaneId !== 'string' ||
        typeof item.toLaneId !== 'string' ||
        typeof item.enabled !== 'boolean' ||
        (laneIds && (!laneIds.has(item.fromLaneId) || !laneIds.has(item.toLaneId)))
      )
        throw new Error('Invalid lane connection override.');
    } else if (item.kind === 'center-line-style') {
      if (
        typeof item.segmentId !== 'string' ||
        !CENTER_LINE_COLORS.has(item.color) ||
        !CENTER_LINE_PATTERNS.has(item.pattern) ||
        (item.double !== undefined && typeof item.double !== 'boolean') ||
        (item.double && (item.color !== 'yellow' || item.pattern !== 'solid')) ||
        (segmentIds && !segmentIds.has(item.segmentId))
      )
        throw new Error('Invalid center line style override.');
    } else if (item.kind === 'lane-separator-style') {
      if (
        typeof item.roadId !== 'string' ||
        (roadIds && !roadIds.has(item.roadId)) ||
        !Number.isInteger(item.leftLaneIndex) ||
        item.rightLaneIndex !== item.leftLaneIndex + 1 ||
        !CENTER_LINE_COLORS.has(item.color) ||
        !CENTER_LINE_PATTERNS.has(item.pattern)
      )
        throw new Error('Invalid lane separator style override.');
    } else if (item.kind === 'edge-line-style') {
      if (
        typeof item.roadId !== 'string' ||
        (directionalRoadIds && !directionalRoadIds.has(item.roadId)) ||
        !['left', 'right'].includes(item.side) ||
        !CENTER_LINE_COLORS.has(item.color) ||
        !CENTER_LINE_PATTERNS.has(item.pattern)
      )
        throw new Error('Invalid edge line style override.');
    } else throw new Error(`Unsupported override kind: ${item.kind}`);
    kept.push(item);
  }
  return { schema: OVERRIDE_SCHEMA, overrides: kept, stale };
}

function applyRoadOverrides(road, overrides, diagnostics) {
  const matching = overrides.overrides.filter(
    (entry) => entry.kind === 'road' && (entry.roadId === road.sourceRoadId || entry.roadId === road.id),
  );
  // A legacy whole-way edit remains the baseline; a segment-specific edit can
  // deliberately refine it after the compiler has introduced split segments.
  matching.sort((first, second) => Number(first.roadId === road.id) - Number(second.roadId === road.id));
  for (const item of matching) {
    for (const key of ['widthMeters', 'laneCount', 'sidewalkLeft', 'sidewalkRight'])
      if (item[key] !== undefined) road[key] = item[key];
    road.appliedOverrideIds.push(item.id);
    for (const key of ['widthMeters', 'laneCount'])
      if (item[key] !== undefined) road.provenance[key] = `override:${item.id}`;
  }
  if (road.widthMeters < road.laneCount * 2.4)
    diagnostics.push(
      diagnostic(
        'warning',
        road.id,
        road.osmWayIds,
        'narrow-lane-width',
        'Configured road width is narrow for the selected lane count.',
        road.centerline[0],
      ),
    );
}

function resolveConnections(endpoints, byNode, overrides, diagnostics) {
  const result = [];
  for (const [nodeId, items] of byNode) {
    const arrivals = items.filter((endpoint) => endpoint.side === 'end');
    const departures = items.filter((endpoint) => endpoint.side === 'start');
    for (const arrival of arrivals)
      for (const departure of departures) {
        if (arrival.roadId === departure.roadId) continue;
        const arrivalRoad = endpoints.find((endpoint) => endpoint.id === arrival.id)?.roadId;
        const departureRoad = endpoints.find((endpoint) => endpoint.id === departure.id)?.roadId;
        if (sameOsmWay(endpoints, arrivalRoad, departureRoad)) continue;
        const override = overrides.overrides.find(
          (entry) =>
            entry.kind === 'junction-connection' &&
            entry.fromEndpointId === arrival.id &&
            entry.toEndpointId === departure.id,
        );
        result.push({
          id: `connection:${arrival.id}:${departure.id}`,
          nodeId,
          fromEndpointId: arrival.id,
          toEndpointId: departure.id,
          enabled: override ? override.enabled : true,
          provenance: override ? `override:${override.id}` : 'osm:shared-node',
        });
      }
    if (items.length > 8)
      diagnostics.push(
        diagnostic(
          'warning',
          `junction:node/${nodeId}`,
          [nodeId],
          'complex-junction',
          'Junction has more than eight directional endpoints and is not compiled as an ordinary junction.',
          items[0].coordinate,
        ),
      );
  }
  // Overrides can add a deliberate movement omitted by the initial inference.
  // Keep it only when both endpoints still belong to the same OSM junction.
  for (const override of overrides.overrides.filter((item) => item.kind === 'junction-connection')) {
    const exists = result.some(
      (connection) =>
        connection.fromEndpointId === override.fromEndpointId && connection.toEndpointId === override.toEndpointId,
    );
    if (exists) continue;
    const from = endpoints.find((endpoint) => endpoint.id === override.fromEndpointId);
    const to = endpoints.find((endpoint) => endpoint.id === override.toEndpointId);
    if (!from || !to || !connectionEndpointsCompatible({ endpoints }, from.id, to.id)) continue;
    result.push({
      id: `connection:${from.id}:${to.id}`,
      nodeId: from.nodeId,
      fromEndpointId: from.id,
      toEndpointId: to.id,
      enabled: override.enabled,
      provenance: `override:${override.id}`,
    });
  }
  return result;
}

function endpointNode(model, endpointId) {
  return model.endpoints.find((endpoint) => endpoint.id === endpointId)?.nodeId;
}
function sameOsmWay(endpoints, firstRoadId, secondRoadId) {
  const roadFor = (roadId) => endpoints.find((endpoint) => endpoint.roadId === roadId)?.roadId;
  const segmentId = (roadId) => roadId.replace(/:(forward|backward)$/, '');
  return segmentId(roadFor(firstRoadId) || firstRoadId) === segmentId(roadFor(secondRoadId) || secondRoadId);
}
function connectionEndpointsCompatible(model, fromId, toId) {
  const from = model.endpoints.find((endpoint) => endpoint.id === fromId);
  const to = model.endpoints.find((endpoint) => endpoint.id === toId);
  if (
    !from ||
    !to ||
    from.roadId === to.roadId ||
    sameOsmWay(model.endpoints, from.roadId, to.roadId) ||
    from.side !== 'end' ||
    to.side !== 'start'
  )
    return false;
  if (from.nodeId === to.nodeId) return true;
  const dx = (from.coordinate[0] - to.coordinate[0]) * 111320 * Math.cos((from.coordinate[1] * Math.PI) / 180);
  const dy = (from.coordinate[1] - to.coordinate[1]) * 111320;
  return Math.hypot(dx, dy) <= 35;
}

function nearbyManualCandidates(endpoints, from) {
  return endpoints
    .filter((to) => to.side === 'start' && to.roadId !== from.roadId && !sameOsmWay(endpoints, from.roadId, to.roadId))
    .map((to) => ({ to, distanceMeters: distanceMeters(from.coordinate, to.coordinate) }))
    .filter((item) => item.distanceMeters <= 35)
    .sort((a, b) => a.distanceMeters - b.distanceMeters)
    .slice(0, 3)
    .map(({ to, distanceMeters: meters }) => ({
      toEndpointId: to.id,
      roadId: to.roadId,
      distanceMeters: Math.round(meters * 10) / 10,
    }));
}

// A single physical intersection is often mapped as several nodes joined by
// short links: a dual carriageway crossing, a slip lane, a staggered junction.
// Each node then compiles its own surface and the shared area between them is
// left as ordinary road, which is what produces the width jumps and stray
// medians around those nodes. Report the clusters so they can be configured as
// `complex-junction-v1`. Detection is advisory only — it never enables a
// template or changes geometry, because flipping a junction between the
// ordinary and complex paths silently on an OSM edit would be unpredictable.
const COMPLEX_CANDIDATE_MAX_LINK_METERS = 30;
const COMPLEX_CANDIDATE_MIN_NODES = 2;
// Short links chain transitively, so a run of closely spaced junctions along
// one street unions into a single 'cluster' that is really a corridor. A real
// intersection stays compact, so bound the cluster by its own diameter: the
// surveyed 珠山湖大道 cluster spans 24.6 m on its four mapped nodes and 40.7 m
// once the neighbouring service-road junction is folded in.
const COMPLEX_CANDIDATE_MAX_DIAMETER_METERS = 45;

function detectComplexJunctionCandidates(model, junctionPlans, options, diagnostics) {
  const configured = new Set(
    (options.junctionTemplates?.clusters || []).flatMap((cluster) => (cluster.nodeIds || []).map(String)),
  );
  const segmentsByNode = new Map();
  for (const endpoint of model.endpoints) {
    const key = String(endpoint.nodeId);
    if (!segmentsByNode.has(key)) segmentsByNode.set(key, new Set());
    segmentsByNode.get(key).add(endpoint.roadId.replace(/:(forward|backward)$/, ''));
  }
  const junctionNodes = new Set(
    [...segmentsByNode].filter(([, segments]) => segments.size >= 3).map(([nodeId]) => nodeId),
  );
  const parent = new Map();
  const find = (id) => {
    if (!parent.has(id)) parent.set(id, id);
    while (parent.get(id) !== id) {
      parent.set(id, parent.get(parent.get(id)));
      id = parent.get(id);
    }
    return id;
  };
  const union = (first, second) => {
    const a = find(first);
    const b = find(second);
    if (a !== b) parent.set(a, b);
  };
  const links = new Map();
  const seenSegments = new Set();
  for (const road of model.roads) {
    if (seenSegments.has(road.segmentId)) continue;
    seenSegments.add(road.segmentId);
    const start = String(road.sourceNodeIds[0]);
    const end = String(road.sourceNodeIds.at(-1));
    if (start === end || !junctionNodes.has(start) || !junctionNodes.has(end)) continue;
    const length = lineLengthMeters(road.centerline);
    if (length > COMPLEX_CANDIDATE_MAX_LINK_METERS) continue;
    union(start, end);
    links.set(road.segmentId, { start, end, length });
  }
  const clusters = new Map();
  for (const nodeId of parent.keys()) {
    const root = find(nodeId);
    if (!clusters.has(root)) clusters.set(root, []);
    clusters.get(root).push(nodeId);
  }
  for (const nodeIds of clusters.values()) {
    if (nodeIds.length < COMPLEX_CANDIDATE_MIN_NODES) continue;
    if (nodeIds.some((nodeId) => configured.has(nodeId))) continue;
    const points = nodeIds.map((nodeId) => junctionPlans.get(nodeId)?.node).filter(Boolean);
    if (points.length !== nodeIds.length) continue;
    const center = points.reduce(
      (sum, point) => [sum[0] + point[0] / points.length, sum[1] + point[1] / points.length],
      [0, 0],
    );
    const spreadMeters = Math.max(...points.map((point) => distanceMeters(center, point)));
    let diameterMeters = 0;
    for (let first = 0; first < points.length; first += 1) {
      for (let second = first + 1; second < points.length; second += 1)
        diameterMeters = Math.max(diameterMeters, distanceMeters(points[first], points[second]));
    }
    if (diameterMeters > COMPLEX_CANDIDATE_MAX_DIAMETER_METERS) continue;
    const inner = [...links.values()].filter((link) => nodeIds.includes(link.start) && nodeIds.includes(link.end));
    const widths = nodeIds.flatMap((nodeId) =>
      (junctionPlans.get(nodeId)?.approaches || []).map((approach) => approach.widthMeters),
    );
    const widestApproach = widths.length ? Math.max(...widths) : 0;
    // Enough core to cover every member node plus the widest approach's half
    // width, with a little slack. A starting point for tuning, not a result.
    const suggestedCoreRadius = Math.min(80, Math.max(12, Math.round(spreadMeters + widestApproach / 2 + 4)));
    diagnostics.push({
      ...diagnostic(
        'info',
        `junction-cluster-candidate:${nodeIds.slice().sort().join('+')}`,
        nodeIds,
        'complex-junction-candidate',
        `检测到 ${nodeIds.length} 个路口节点由 ${inner.length} 条短路段（最长 ${Math.round(Math.max(...inner.map((link) => link.length)) * 10) / 10} 米）相连，可能是同一个物理路口。当前按独立路口编译；如需合并请在 nativeRoad.junctionTemplates.clusters 中配置。`,
        center,
      ),
      suggestedCluster: {
        template: 'complex-junction-v1',
        nodeIds: nodeIds.slice().sort(),
        nodeCount: nodeIds.length,
        spreadMeters: Math.round(spreadMeters * 10) / 10,
        diameterMeters: Math.round(diameterMeters * 10) / 10,
        longestLinkMeters: Math.round(Math.max(...inner.map((link) => link.length)) * 10) / 10,
        widestApproachMeters: Math.round(widestApproach * 100) / 100,
        coreRadiusMeters: suggestedCoreRadius,
      },
    });
  }
}

function compileGeometry(model, overrides = { overrides: [] }, options = {}) {
  const diagnostics = [...model.diagnostics];
  const junctionPlans = compileJunctionPlans(model, options, diagnostics);
  detectComplexJunctionCandidates(model, junctionPlans, options, diagnostics);
  const features = [];
  const activeClusters = options.junctionTemplates?.enabled ? options.junctionTemplates.clusters || [] : [];
  const clusterByNode = new Map(
    activeClusters.flatMap((cluster) => cluster.nodeIds.map((nodeId) => [String(nodeId), cluster])),
  );
  const complexClusterCenters = new Map(
    activeClusters
      .filter((cluster) => cluster.template === 'complex-junction-v1')
      .map((cluster) => {
        const points = cluster.nodeIds.map((nodeId) => junctionPlans.get(String(nodeId))?.node).filter(Boolean);
        const center = points.length
          ? points.reduce(
              (sum, point) => [sum[0] + point[0] / points.length, sum[1] + point[1] / points.length],
              [0, 0],
            )
          : null;
        return [cluster.id, center];
      }),
  );
  const emittedSegments = new Set();
  const generatedComplexSidewalks = [];
  const generatedComplexCrosswalks = [];
  const generatedComplexStopLines = [];
  for (const road of model.roads) {
    const segmentKey = road.segmentId;
    if (emittedSegments.has(segmentKey)) continue;
    emittedSegments.add(segmentKey);
    const directions = model.roads.filter((item) => item.segmentId === segmentKey);
    const startCluster = clusterByNode.get(String(road.sourceNodeIds[0]));
    const endCluster = clusterByNode.get(String(road.sourceNodeIds.at(-1)));
    if (
      startCluster?.template === 'complex-junction-v1' &&
      endCluster?.template === 'complex-junction-v1' &&
      startCluster.id === endCluster.id
    )
      continue;
    const totalWidth = directions.reduce((sum, item) => sum + item.widthMeters, 0);
    // The approach surface stops at the junction cutback. The junction layer
    // owns the intervening rounded corners; leaving approaches untrimmed
    // would cover that outline with rectangular road ends in Blender/Cesium.
    const cluster =
      clusterByNode.get(String(road.sourceNodeIds[0])) || clusterByNode.get(String(road.sourceNodeIds.at(-1)));
    if (cluster?.template === 'complex-junction-v1') {
      const center = complexClusterCenters.get(cluster.id);
      const length = lineLengthMeters(road.centerline);
      const farEndpoint = cluster.nodeIds.map(String).includes(String(road.sourceNodeIds[0]))
        ? road.centerline.at(-1)
        : road.centerline[0];
      const outerRadius = complexJunctionMetrics(cluster).approachOuterRadius;
      if (center && length < outerRadius + 8 && distanceMeters(farEndpoint, center) < outerRadius) continue;
    }
    const line =
      cluster?.template === 'complex-junction-v1'
        ? trimLineAtComplexCluster(
            road.centerline,
            road.sourceNodeIds,
            junctionPlans,
            cluster,
            complexClusterCenters.get(cluster.id),
          )
        : trimLineAtJunctions(road.centerline, road.sourceNodeIds, junctionPlans);
    const ring = roadRing(line, totalWidth);
    if (!ring) {
      diagnostics.push(
        diagnostic(
          'error',
          road.id,
          road.osmWayIds,
          'unclosed-road-surface',
          'Could not construct a valid road polygon from this centerline.',
          road.centerline[0],
        ),
      );
      continue;
    }
    const surfaceId = road.segmentId.endsWith('/0')
      ? `surface:way/${road.osmWayIds.join(',')}`
      : `surface:${segmentKey}`;
    features.push({
      type: 'Feature',
      properties: {
        native_id: surfaceId,
        cluster_id: cluster?.template === 'complex-junction-v1' ? cluster.id : null,
        directional_road_ids: directions.map((item) => item.id).join(','),
        osm_way_ids: road.osmWayIds.join(','),
        source_road_id: road.sourceRoadId,
        width_m: totalWidth,
        lane_count: directions.reduce((sum, item) => item.laneCount + sum, 0),
        provenance: JSON.stringify(directions.map((item) => item.provenance)),
        override_ids: directions.flatMap((item) => item.appliedOverrideIds).join(','),
      },
      geometry: { type: 'Polygon', coordinates: [ring] },
    });
  }
  for (const [nodeId, plan] of junctionPlans) {
    if (plan.clusterId && activeComplexCluster(options, plan.clusterId)) continue;
    if (!plan.template) continue;
    for (const approach of plan.approaches) {
      const transition = templateApproachRing(approach, plan);
      if (!transition) {
        diagnostics.push(
          diagnostic(
            'warning',
            `junction:node/${nodeId}`,
            [nodeId],
            'junction-template-approach-fallback',
            '进口道路长度不足以生成规整过渡面，已保留该进口的 native 直筒道路。',
            plan.node,
          ),
        );
        continue;
      }
      features.push({
        type: 'Feature',
        properties: {
          native_id: `junction-approach:${plan.template}:node/${nodeId}:${approach.segmentId}`,
          osm_node_id: nodeId,
          segment_id: approach.segmentId,
          directional_road_ids: approach.roadIds.join(','),
          width_m: approach.widthMeters,
          approach_width_m: Math.round(approach.widthMeters * plan.approachWidthMultiplier * 10) / 10,
          approach_length_m: Math.round(transition.lengthMeters * 10) / 10,
          template: plan.template,
          provenance: 'native-road-junction-approach-template/v1',
        },
        geometry: { type: 'Polygon', coordinates: [transition.ring] },
      });
    }
  }
  for (const cluster of activeClusters) {
    if (cluster.template !== 'complex-junction-v1') continue;
    const generated = buildComplexJunctionGeometry(model, cluster, {
      junctionPlans,
      diagnostic,
      distanceMeters,
      lineLengthMeters,
      pointAlongLine,
      offsetCoordinate,
      headingAtEndpoint,
      headingVector,
      circleRing,
    });
    features.push(...generated.features);
    if (generated.crosswalks) generatedComplexCrosswalks.push(...generated.crosswalks);
    if (generated.stopLines) generatedComplexStopLines.push(...generated.stopLines);
    if (generated.islands) generatedComplexSidewalks.push(...generated.islands);
    diagnostics.push(...generated.diagnostics);
  }
  const lanes = compileLaneCenterlines(model, diagnostics, junctionPlans, options, {
    crosswalks: generatedComplexCrosswalks,
    stopLines: generatedComplexStopLines,
  });
  const edgeLines =
    options.edgeLines === false ? [] : compileEdgeLines(model, overrides, junctionPlans, options, features);
  const controls = compileControlMarkings(model, lanes, diagnostics, junctionPlans);
  const allControls = {
    crosswalks: [...controls.crosswalks, ...generatedComplexCrosswalks],
    stopLines: [...controls.stopLines, ...generatedComplexStopLines],
  };
  const centerLines = compileCenterLines(model, overrides, junctionPlans, allControls, diagnostics, options);
  const markings = compileLaneMarkings(model, overrides, lanes, diagnostics, junctionPlans, allControls, options);
  markings.separators.push(
    ...compileComplexLaneSeparators(lanes.features, [...allControls.crosswalks, ...allControls.stopLines]),
  );
  markings.directionArrows.push(...compileComplexPreviewArrows(lanes.features, generatedComplexStopLines));
  const sidewalks = compileSidewalkSurfaces(model, diagnostics, junctionPlans, options);
  // Complex crosswalks are generated from native approach tangents; do not
  // synthesize side strips that can be mistaken for crosswalks.
  sidewalks.push(...generatedComplexSidewalks);
  const connectorResult = compileConnectors(model, lanes, diagnostics, overrides, junctionPlans);
  const junctionFeatures = compileJunctionSurfaces(
    model,
    junctionPlans,
    connectorResult.features,
    connectorResult.movements,
    diagnostics,
    options,
  );
  validateConnectorContainment(connectorResult.features, junctionFeatures, diagnostics);
  return {
    roadSurface: { type: 'FeatureCollection', features },
    edgeLines: { type: 'FeatureCollection', features: edgeLines },
    sidewalkSurface: { type: 'FeatureCollection', features: sidewalks },
    intersectionSurface: { type: 'FeatureCollection', features: junctionFeatures },
    laneCenterlines: { type: 'FeatureCollection', features: lanes.features },
    laneSeparators: { type: 'FeatureCollection', features: markings.separators },
    centerLines: { type: 'FeatureCollection', features: centerLines },
    directionArrows: { type: 'FeatureCollection', features: markings.directionArrows },
    turnArrows: { type: 'FeatureCollection', features: markings.turnArrows },
    crosswalks: { type: 'FeatureCollection', features: [...controls.crosswalks, ...generatedComplexCrosswalks] },
    vehicleStopLines: { type: 'FeatureCollection', features: [...controls.stopLines, ...generatedComplexStopLines] },
    connectors: { type: 'FeatureCollection', features: connectorResult.features },
    movements: connectorResult.movements,
    diagnostics,
  };
}

function compileComplexPreviewArrows(features, stopLines) {
  const result = [];
  for (const feature of features) {
    if (
      !feature.properties?.cluster_preview ||
      !feature.properties.incoming ||
      feature.properties.maneuver === 'outbound'
    )
      continue;
    const line = feature.geometry?.coordinates || [];
    if (line.length < 2) continue;
    const stopLine = stopLines.find((candidate) => candidate.properties?.road_id === feature.properties.road_id);
    if (!stopLine) continue;
    const stopRing = stopLine.geometry?.coordinates?.[0];
    if (!stopRing || stopRing.length < 4) continue;
    const stopPoints = stopRing.slice(0, -1);
    const stopCenter = [
      stopPoints.reduce((sum, point) => sum + point[0], 0) / stopPoints.length,
      stopPoints.reduce((sum, point) => sum + point[1], 0) / stopPoints.length,
    ];
    const placement = distanceMeters(line.at(-1), stopCenter) + 8;
    const placementInfo = pointAndAxisAlongLine(line, Math.max(0, lineLengthMeters(line) - placement));
    if (!placementInfo) continue;
    const rings = arrowRingsAt(feature.properties.maneuver, placementInfo.point, placementInfo.axis);
    for (let part = 0; part < rings.length; part += 1)
      result.push({
        type: 'Feature',
        properties: {
          native_id: `${feature.properties.native_id}:arrow:${part}`,
          road_id: feature.properties.road_id,
          lane_id: feature.properties.native_id,
          cluster_id: feature.properties.cluster_id,
          cluster_preview: true,
          maneuver: feature.properties.maneuver,
          travel_heading_deg: headingDegrees(line[0], line.at(-1)),
          placement_distance_from_stop_meters: 8,
          provenance: 'native-road-complex-preview-arrow/v2-stop-anchored',
        },
        geometry: { type: 'Polygon', coordinates: [rings[part]] },
      });
  }
  return result;
}

function compileComplexLaneSeparators(features, controls = []) {
  const groups = new Map();
  for (const feature of features) {
    if (!feature.properties?.cluster_preview || !feature.properties.road_id) continue;
    if (!groups.has(feature.properties.road_id)) groups.set(feature.properties.road_id, []);
    groups.get(feature.properties.road_id).push(feature);
  }
  const result = [];
  for (const [roadId, lanes] of groups) {
    lanes.sort((first, second) => first.properties.lane_index - second.properties.lane_index);
    for (let index = 1; index < lanes.length; index += 1) {
      const left = lanes[index - 1].geometry.coordinates;
      const right = lanes[index].geometry.coordinates;
      if (left.length !== right.length) continue;
      const line = left.map((point, pointIndex) => [
        (point[0] + right[pointIndex][0]) / 2,
        (point[1] + right[pointIndex][1]) / 2,
      ]);
      const visibleLine = trimLineBeforeFirstControl(line, controls, 0.12);
      const ring = visibleLine ? roadRing(visibleLine, 0.12) : null;
      if (!ring) continue;
      result.push({
        type: 'Feature',
        properties: {
          native_id: `complex-lane-separator:${roadId}:${index}-${index + 1}`,
          road_id: roadId,
          cluster_id: lanes[0].properties.cluster_id,
          left_lane_index: index,
          right_lane_index: index + 1,
          color: 'white',
          pattern: 'solid',
          effective_style: 'white-solid',
          provenance: 'native-road-complex-lane-separator/v1',
        },
        geometry: { type: 'Polygon', coordinates: [ring] },
      });
    }
  }
  return result;
}

function trimLineBeforeFirstControl(line, controls, width) {
  const total = lineLengthMeters(line);
  const step = 0.25;
  for (let distance = step; distance <= total; distance += step) {
    const placement = pointAndAxisAlongLine(line, Math.min(total, distance - step / 2));
    if (!placement) continue;
    const ring = rectangleAt(placement.point, placement.axis, [-placement.axis[1], placement.axis[0]], step, width, 0);
    if (!ringsOverlapControl([ring], controls)) continue;
    let cutoff = Math.max(0, distance - step - 0.12);
    while (cutoff > 0.5) {
      const candidate = roadRing([line[0], pointAlongLine(line, cutoff)], width);
      if (candidate && !ringsOverlapControl([candidate], controls)) return [line[0], pointAlongLine(line, cutoff)];
      cutoff -= 0.25;
    }
    return null;
  }
  return line;
}

// `trimLineBeforeFirstControl` always keeps the head of the line, so the caller
// must hand it a line that already runs from the road towards the junction.
// Lane centerlines arrive in either orientation (a preview lane runs inward
// from the outer radius, an outgoing road lane runs outward from the cluster
// node), so orient by radius first and restore the original order afterwards.
function trimLaneOutsideControls(line, controls, width, center) {
  if (!controls.length || !center || !Array.isArray(line) || line.length < 2) return line;
  const outwardFirst = distanceMeters(line[0], center) >= distanceMeters(line.at(-1), center);
  const oriented = outwardFirst ? line : [...line].reverse();
  const trimmed = trimLineBeforeFirstControl(oriented, controls, width);
  if (!trimmed) return null;
  return outwardFirst ? trimmed : [...trimmed].reverse();
}

// Reference identity is not reliable here: the reversed path rebuilds the array
// even when nothing was cut. Compare travelled length instead.
function laneWasClipped(original, visible) {
  return Boolean(visible) && lineLengthMeters(visible) < lineLengthMeters(original) - 0.01;
}

function compileEdgeLines(model, overrides, junctionPlans, options = {}, roadSurfaces = []) {
  const features = [];
  const clusters = options.junctionTemplates?.enabled ? options.junctionTemplates.clusters || [] : [];
  const clusterByNode = new Map(
    clusters.flatMap((cluster) => cluster.nodeIds.map((nodeId) => [String(nodeId), cluster])),
  );
  const clusterCenters = new Map(clusters.map((cluster) => [cluster.id, clusterCenter(cluster, junctionPlans)]));
  // Roads swallowed by a complex cluster never get a surface. Deriving their
  // edge from the centerline anyway paints a curb across bare ground, so take
  // the surfaces actually emitted as the authority on what can be outlined.
  const surfaced = new Set(
    roadSurfaces
      .flatMap((feature) => String(feature.properties?.directional_road_ids || '').split(','))
      .filter(Boolean),
  );
  for (const road of model.roads) {
    if (surfaced.size && !surfaced.has(road.id)) continue;
    // The road surface is one polygon per segment, centred on this centerline
    // and spanning the sum of both directions. Deriving the edge from a single
    // direction's width puts it half a carriageway inside the asphalt.
    const directions = model.roads.filter((item) => item.segmentId === road.segmentId);
    const totalWidth = directions.reduce((sum, item) => sum + item.widthMeters, 0);
    const bidirectional = directions.length > 1;
    // Match the surface's trim exactly. A cluster road is cut at the cluster
    // boundary, not at the ordinary junction cutback; using the cutback here
    // runs the edge line out past the asphalt it is supposed to outline.
    const cluster =
      clusterByNode.get(String(road.sourceNodeIds[0])) || clusterByNode.get(String(road.sourceNodeIds.at(-1)));
    const line =
      cluster?.template === 'complex-junction-v1'
        ? trimLineAtComplexCluster(
            road.centerline,
            road.sourceNodeIds,
            junctionPlans,
            cluster,
            clusterCenters.get(cluster.id),
          )
        : trimLineAtJunctions(road.centerline, road.sourceNodeIds, junctionPlans);
    // On a two-way segment, the inner edge is the road centre boundary and is
    // owned by center_lines. Emit only each directional carriageway's outer
    // edge; emitting both sides makes the layer look like a second centreline.
    const offsets = bidirectional ? [-1] : [-1, 1];
    for (const offset of offsets) {
      const side = offset < 0 ? 'right' : 'left';
      const style = edgeLineStyle(overrides, road.id, side);
      const centerline = offsetLine(line, (offset * totalWidth) / 2);
      if (!centerline) continue;
      if (style.pattern === 'solid') {
        const ring = roadRing(centerline, 0.12);
        if (ring) features.push(edgeLineFeature(road, side, style, ring));
        continue;
      }
      for (let distance = 1, part = 1; distance + 1 <= lineLengthMeters(centerline); distance += 4, part += 1) {
        const placement = pointAndAxisAlongLine(centerline, distance);
        if (!placement) continue;
        features.push(
          edgeLineFeature(
            road,
            side,
            style,
            rectangleAt(placement.point, placement.axis, [-placement.axis[1], placement.axis[0]], 2, 0.12, 0),
            part,
          ),
        );
      }
    }
  }
  return features;
}

function edgeLineFeature(road, side, style, ring, part = null) {
  return {
    type: 'Feature',
    properties: {
      native_id: `edge-line:${road.id}:${side}${part ? `:${part}` : ''}`,
      road_id: road.id,
      side,
      osm_way_ids: road.osmWayIds.join(','),
      color: style.color,
      pattern: style.pattern,
      effective_style: `${style.color}-${style.pattern}`,
      provenance: 'native-road-edge-line/v1',
    },
    geometry: { type: 'Polygon', coordinates: [ring] },
  };
}

function compileCenterLines(model, overrides, junctionPlans, controls, diagnostics, options = {}) {
  const features = [];
  const controlFeatures = [...controls.crosswalks, ...controls.stopLines];
  const segments = new Map();
  for (const road of model.roads) {
    if (!segments.has(road.segmentId)) segments.set(road.segmentId, []);
    segments.get(road.segmentId).push(road);
  }
  for (const [segmentId, roads] of segments) {
    const forward = roads.find((road) => road.direction === 'forward');
    const backward = roads.find((road) => road.direction === 'backward');
    if (roads.length !== 2 || !forward || !backward || forward.highway === 'service' || backward.highway === 'service')
      continue;
    const cluster = clusterForRoad(forward, options) || clusterForRoad(backward, options);
    const internalCluster = cluster && roadInternalToCluster(forward, cluster);
    const line = cluster
      ? trimLineAtComplexCluster(
          forward.centerline,
          forward.sourceNodeIds,
          junctionPlans,
          cluster,
          clusterCenter(cluster, junctionPlans),
        )
      : trimLineAtJunctions(forward.centerline, forward.sourceNodeIds, junctionPlans);
    const length = lineLengthMeters(line);
    if (line.length < 2 || !Number.isFinite(length)) {
      diagnostics.push(
        diagnostic(
          'warning',
          segmentId,
          forward.osmWayIds,
          'invalid-center-line',
          '双向道路无法生成有效道路中心虚线。',
          forward.centerline[0],
        ),
      );
      continue;
    }
    const style = centerLineStyle(overrides, segmentId);
    const visibleLine = trimLineBeforeFirstControl(line, controlFeatures, CENTER_LINE_WIDTH_METERS);
    const visibleLength = visibleLine ? lineLengthMeters(visibleLine) : 0;
    if (!visibleLine || visibleLength < CENTER_LINE_DASH_LENGTH_METERS) continue;
    const gap = style.pattern === 'solid' ? 0 : CENTER_LINE_DASH_GAP_METERS;
    const markLength =
      CENTER_LINE_DASH_LENGTH_METERS + (style.pattern === 'solid' ? CENTER_LINE_SOLID_OVERLAP_METERS : 0);
    for (
      let start = 0, dashIndex = 1;
      start + markLength <= visibleLength;
      start += CENTER_LINE_DASH_LENGTH_METERS + gap, dashIndex += 1
    ) {
      const placement = pointAndAxisAlongLine(visibleLine, start + markLength / 2);
      if (!placement) continue;
      const clearanceRing = rectangleAt(
        placement.point,
        placement.axis,
        [-placement.axis[1], placement.axis[0]],
        markLength + CENTER_LINE_CONTROL_CLEARANCE_METERS * 2,
        CENTER_LINE_WIDTH_METERS + CENTER_LINE_CONTROL_CLEARANCE_METERS * 2,
        0,
      );
      for (const offset of style.double ? [-0.16, 0.16] : [0]) {
        const ring = rectangleAt(
          placement.point,
          placement.axis,
          [-placement.axis[1], placement.axis[0]],
          markLength,
          CENTER_LINE_WIDTH_METERS,
          offset,
        );
        features.push({
          type: 'Feature',
          properties: {
            native_id: `center-line:${segmentId}:${dashIndex}:${offset}`,
            segment_id: segmentId,
            road_id: forward.id,
            cluster_id: cluster?.id || null,
            cluster_internal: Boolean(internalCluster),
            cluster_preview_hidden: Boolean(internalCluster),
            directional_road_ids: roads.map((road) => road.id).join(','),
            osm_way_ids: forward.osmWayIds.join(','),
            dash_index: dashIndex,
            dash_length_m: markLength,
            dash_gap_m: gap,
            color: style.color,
            pattern: style.pattern,
            double: Boolean(style.double),
            effective_style: `${style.double ? 'double-' : ''}${style.color}-${style.pattern}`,
            placement_rule: 'native-bidirectional-centerline/v1',
            provenance: 'native-road-center-line/v1',
          },
          geometry: { type: 'Polygon', coordinates: [ring] },
        });
      }
    }
  }
  return features;
}

function centerLineStyle(overrides, segmentId) {
  const override = overrides.overrides.find(
    (item) => item.kind === 'center-line-style' && item.segmentId === segmentId,
  );
  return override
    ? { color: override.color, pattern: override.pattern, double: Boolean(override.double) }
    : { color: 'yellow', pattern: 'dashed', double: false };
}

function edgeLineStyle(overrides, roadId, side) {
  const value = overrides.overrides.find(
    (item) => item.kind === 'edge-line-style' && item.roadId === roadId && item.side === side,
  );
  return value ? { color: value.color, pattern: value.pattern } : { color: 'white', pattern: 'solid' };
}

function compileControlMarkings(model, lanes, diagnostics, junctionPlans = new Map()) {
  const crosswalks = [];
  const stopLines = [];
  const arrivalEndpointIds = new Set(
    model.connections.filter((connection) => connection.enabled).map((connection) => connection.fromEndpointId),
  );
  for (const crossing of model.crossings || []) {
    const candidates = model.roads
      .filter((road) => crossing.osmWayIds.includes(road.osmWayIds[0]))
      .flatMap((road) =>
        (lanes.byRoadId.get(road.id) || [])
          .map((lane) => ({
            road,
            lane,
            placement: nearestLanePlacement(lane.coordinates, crossing.coordinate),
            junctionDistanceMeters: distanceMeters(crossing.coordinate, road.centerline.at(-1)),
          }))
          .filter((item) => item.placement),
      );
    const candidate = candidates.sort((a, b) => a.placement.distance - b.placement.distance)[0];
    if (!candidate || candidate.placement.distance > 12) {
      diagnostics.push(
        diagnostic(
          'warning',
          `crossing:node/${crossing.id}`,
          [crossing.id],
          'crossing-no-native-lane',
          '人行横道无法匹配到安全的原生车道，未生成标线。',
          crossing.coordinate,
        ),
      );
      continue;
    }
    const approach = candidates
      .filter(
        (item) =>
          arrivalEndpointIds.has(`endpoint:${item.road.id}:end`) &&
          item.junctionDistanceMeters > STOP_LINE_OFFSET_METERS &&
          item.junctionDistanceMeters <= STOP_LINE_MAX_APPROACH_DISTANCE_METERS,
      )
      .sort(
        (a, b) => a.junctionDistanceMeters - b.junctionDistanceMeters || a.placement.distance - b.placement.distance,
      )[0];
    const crosswalkCandidate = approach || candidate;
    const junctionInsetMeters = approach ? crossingJunctionInset(approach, junctionPlans) : 0;
    const controlCenter = offsetByMeters(crossing.coordinate, crosswalkCandidate.placement.axis, junctionInsetMeters);
    const { axis } = crosswalkCandidate.placement;
    const across = [-axis[1], axis[0]];
    for (let index = 0; index < 6; index += 1)
      crosswalks.push(
        controlFeature(
          'crosswalk',
          crossing,
          crosswalkCandidate,
          index + 1,
          rectangleAt(controlCenter, axis, across, 3, 0.45, -2.25 + index * 0.9),
          { junctionInsetMeters },
        ),
      );
    if (!approach) {
      diagnostics.push(
        diagnostic(
          'info',
          `crossing:node/${crossing.id}`,
          [crossing.id],
          'crossing-no-safe-stop-line',
          '人行横道没有可确认的路口进口车道，保留斑马线但未生成停止线。',
          crossing.coordinate,
        ),
      );
      continue;
    }
    const rawRoadPlacement = nearestLanePlacement(approach.road.centerline, controlCenter);
    const laneOffset = rawRoadPlacement ? project(approach.placement.point, rawRoadPlacement.point) : [0, 0];
    const lateralOffset = laneOffset[0] * across[0] + laneOffset[1] * across[1];
    const laneCenterAtCrossing = offsetByMeters(controlCenter, across, lateralOffset);
    const stopCenter = offsetByMeters(laneCenterAtCrossing, approach.placement.axis, -STOP_LINE_OFFSET_METERS);
    stopLines.push(
      controlFeature(
        'stop-line',
        crossing,
        approach,
        1,
        rectangleAt(stopCenter, across, approach.placement.axis, approach.road.widthMeters, 0.45, 0),
        { junctionInsetMeters },
      ),
    );
  }
  return { crosswalks, stopLines };
}

function crossingJunctionInset(candidate, junctionPlans) {
  const junctionNodeId = candidate.road.sourceNodeIds.at(-1);
  const plan = junctionPlans.get(junctionNodeId);
  if (!plan) return 0;
  const targetDistance = Math.max(0, plan.cutbackMeters - CROSSWALK_JUNCTION_INSET_METERS);
  return Math.min(CROSSWALK_MAX_JUNCTION_INSET_METERS, Math.max(0, candidate.junctionDistanceMeters - targetDistance));
}

function nearestLanePlacement(line, target) {
  let best = null;
  let traversedMeters = 0;
  for (let index = 1; index < line.length; index += 1) {
    const a = line[index - 1];
    const b = line[index];
    const vector = project(b, a);
    const length = Math.hypot(...vector);
    if (!length) continue;
    const relative = project(target, a);
    const ratio = Math.max(0, Math.min(1, (relative[0] * vector[0] + relative[1] * vector[1]) / (length * length)));
    const point = interpolate(a, b, ratio);
    const distance = distanceMeters(point, target);
    if (!best || distance < best.distance)
      best = {
        point,
        axis: [vector[0] / length, vector[1] / length],
        distance,
        distanceToEndMeters: lineLengthMeters(line) - traversedMeters - length * ratio,
      };
    traversedMeters += length;
  }
  return best;
}
function offsetByMeters(point, axis, meters) {
  return unproject([axis[0] * meters, axis[1] * meters], point);
}
function rectangleAt(center, axis, across, length, width, offset) {
  const shifted = offsetByMeters(center, across, offset);
  const corners = [
    [-length / 2, -width / 2],
    [length / 2, -width / 2],
    [length / 2, width / 2],
    [-length / 2, width / 2],
  ].map(([forward, side]) =>
    unproject([axis[0] * forward + across[0] * side, axis[1] * forward + across[1] * side], shifted),
  );
  return [...corners, corners[0]];
}
function controlFeature(kind, crossing, candidate, part, ring, placement = {}) {
  const stop = kind === 'stop-line';
  return {
    type: 'Feature',
    properties: {
      native_id: `${kind}:node/${crossing.id}:${part}`,
      crossing_node_id: crossing.id,
      road_id: candidate.road.id,
      lane_id: candidate.lane.id,
      osm_way_ids: candidate.road.osmWayIds.join(','),
      direction: candidate.road.direction,
      placement_method: 'native-lane-nearest-point/v1',
      junction_inset_m: Math.round((placement.junctionInsetMeters || 0) * 100) / 100,
      provenance: stop ? 'native-road-stop-line/v1' : 'native-road-crosswalk/v1',
    },
    geometry: { type: 'Polygon', coordinates: [ring] },
  };
}

function compileLaneMarkings(model, overrides, lanes, diagnostics, junctionPlans, controls, options = {}) {
  const separators = [];
  const directionArrows = [];
  const turnArrows = [];
  const controlFeatures = [...controls.crosswalks, ...controls.stopLines];
  for (const road of model.roads) {
    const cluster = clusterForRoad(road, options);
    const internalCluster = cluster && roadInternalToCluster(road, cluster);
    const roadLanes = (lanes.markingByRoadId || lanes.byRoadId).get(road.id) || [];
    for (let index = 1; index < roadLanes.length; index += 1) {
      const left = roadLanes[index - 1].coordinates;
      const right = roadLanes[index].coordinates;
      if (left.length !== right.length) continue;
      const centerline = left.map((point, pointIndex) => [
        (point[0] + right[pointIndex][0]) / 2,
        (point[1] + right[pointIndex][1]) / 2,
      ]);
      const style = laneSeparatorStyle(overrides, road.id, index, index + 1);
      const properties = {
        road_id: road.id,
        left_lane_index: index,
        right_lane_index: index + 1,
        cluster_id: cluster?.id || null,
        cluster_internal: Boolean(internalCluster),
        cluster_preview_hidden: Boolean(internalCluster),
        osm_way_ids: road.osmWayIds.join(','),
        color: style.color,
        pattern: style.pattern,
        effective_style: `${style.color}-${style.pattern}`,
        provenance: 'native-road-lane-separator/v1',
      };
      if (style.pattern === 'solid') {
        const visibleLine = trimLineBeforeFirstControl(centerline, controlFeatures, 0.12);
        const ring = visibleLine ? roadRing(visibleLine, 0.12) : null;
        if (ring)
          separators.push({
            type: 'Feature',
            properties: { native_id: `lane-separator:${road.id}:${index}-${index + 1}`, ...properties },
            geometry: { type: 'Polygon', coordinates: [ring] },
          });
      } else {
        const visibleLine = trimLineBeforeFirstControl(centerline, controlFeatures, 0.12);
        const visibleLength = visibleLine ? lineLengthMeters(visibleLine) : 0;
        for (let distance = 1, part = 1; visibleLine && distance + 1 <= visibleLength; distance += 4, part += 1) {
          const placement = pointAndAxisAlongLine(visibleLine, distance);
          if (!placement) continue;
          const ring = rectangleAt(
            placement.point,
            placement.axis,
            [-placement.axis[1], placement.axis[0]],
            2,
            0.12,
            0,
          );
          separators.push({
            type: 'Feature',
            properties: { native_id: `lane-separator:${road.id}:${index}-${index + 1}:${part}`, ...properties },
            geometry: { type: 'Polygon', coordinates: [ring] },
          });
        }
      }
    }
    for (const lane of roadLanes)
      directionArrows.push(
        ...directionArrowFeatures(road, lane, controlFeatures, diagnostics).map((feature) => ({
          ...feature,
          properties: {
            ...feature.properties,
            cluster_id: cluster?.id || null,
            cluster_internal: Boolean(internalCluster),
            cluster_preview_hidden: Boolean(internalCluster),
          },
        })),
      );
    const turns = road.tags[`turn:lanes:${road.direction}`] ?? road.tags['turn:lanes'];
    const maneuvers = turns ? String(turns).split('|') : [];
    for (let index = 0; index < roadLanes.length; index += 1) {
      const lane = roadLanes[index];
      const explicitManeuver = maneuvers[index];
      if (!explicitManeuver) continue;
      const maneuver = normalizeManeuver(explicitManeuver);
      if (!lane) {
        diagnostics.push(
          diagnostic(
            'warning',
            road.id,
            road.osmWayIds,
            'turn-arrow-lane-missing',
            '转向标签引用了不存在的车道，未生成箭头。',
            road.centerline.at(-1),
          ),
        );
        continue;
      }
      if (!arrowRingsAt(maneuver, lane.coordinates.at(-1), [0, 1]).length) {
        diagnostics.push(
          diagnostic(
            'info',
            lane.id,
            road.osmWayIds,
            'turn-arrow-unsupported',
            '转向标签不在当前已测试的箭头集合中，未生成箭头。',
            lane.coordinates.at(-1),
          ),
        );
        continue;
      }
      if (lineLengthMeters(lane.coordinates) < 8) {
        diagnostics.push(
          diagnostic(
            'warning',
            lane.id,
            road.osmWayIds,
            'turn-arrow-no-safe-placement',
            '驶入路口前的车道过短，未生成转向箭头。',
            lane.coordinates.at(-1),
          ),
        );
        continue;
      }
      const previous = lane.coordinates.at(-2);
      const end = lane.coordinates.at(-1);
      const meters = project(end, end);
      const vector = project(previous, end);
      const length = Math.hypot(-vector[0], -vector[1]);
      const axis = length ? [-vector[0] / length, -vector[1] / length] : null;
      const placement = axis
        ? [6, 10, 14, 18, 22].find(
            (distance) =>
              distance < lineLengthMeters(lane.coordinates) - 2 &&
              !ringsOverlapControl(
                arrowRingsAt(maneuver, pointAlongLine([...lane.coordinates].reverse(), distance), axis),
                controlFeatures,
              ),
          )
        : null;
      if (!placement) {
        diagnostics.push(
          diagnostic(
            'info',
            lane.id,
            road.osmWayIds,
            'turn-arrow-control-conflict',
            '转向箭头会压住斑马线或停止线，未生成该箭头。',
            lane.coordinates.at(-1),
          ),
        );
        continue;
      }
      const center = pointAlongLine([...lane.coordinates].reverse(), placement);
      const rings = arrowRingsAt(maneuver, center, axis);
      if (!rings.length) continue;
      for (let part = 0; part < rings.length; part += 1)
        turnArrows.push({
          type: 'Feature',
          properties: {
            native_id: `turn-arrow:${lane.id}:${maneuver}:${part}`,
            road_id: road.id,
            lane_id: lane.id,
            cluster_id: cluster?.id || null,
            cluster_internal: Boolean(internalCluster),
            cluster_preview_hidden: Boolean(internalCluster),
            osm_way_ids: road.osmWayIds.join(','),
            direction: road.direction,
            lane_index: lane.index,
            maneuver,
            arrow_part: part,
            placement_distance_meters: placement,
            provenance: 'native-road-turn-arrow/v1',
          },
          geometry: { type: 'Polygon', coordinates: [rings[part]] },
        });
    }
  }
  return { separators, directionArrows, turnArrows };
}

function clusterForRoad(road, options) {
  const clusters = options.junctionTemplates?.enabled ? options.junctionTemplates.clusters || [] : [];
  return (
    clusters.find(
      (cluster) =>
        cluster.template === 'complex-junction-v1' &&
        road.sourceNodeIds.some((nodeId) => cluster.nodeIds.map(String).includes(String(nodeId))),
    ) || null
  );
}

function roadInternalToCluster(road, cluster) {
  const nodeIds = new Set(cluster.nodeIds.map(String));
  return nodeIds.has(String(road.sourceNodeIds[0])) && nodeIds.has(String(road.sourceNodeIds.at(-1)));
}

function clusterCenter(cluster, junctionPlans) {
  const points = cluster.nodeIds.map((nodeId) => junctionPlans.get(String(nodeId))?.node).filter(Boolean);
  return points.length
    ? points.reduce((sum, point) => [sum[0] + point[0] / points.length, sum[1] + point[1] / points.length], [0, 0])
    : null;
}

function angularDistance(first, second) {
  return Math.abs(((first - second + 180) % 360) - 180);
}

function laneSeparatorStyle(overrides, roadId, leftLaneIndex, rightLaneIndex) {
  const value = overrides.overrides.find(
    (item) =>
      item.kind === 'lane-separator-style' &&
      item.roadId === roadId &&
      item.leftLaneIndex === leftLaneIndex &&
      item.rightLaneIndex === rightLaneIndex,
  );
  return value ? { color: value.color, pattern: value.pattern } : { color: 'white', pattern: 'dashed' };
}

function directionArrowFeatures(road, lane, controlFeatures, diagnostics) {
  const length = lineLengthMeters(lane.coordinates);
  const features = [];
  for (
    let distance = DIRECTION_ARROW_ENDPOINT_BUFFER_METERS, sequence = 1;
    distance <= length - DIRECTION_ARROW_ENDPOINT_BUFFER_METERS;
    distance += DIRECTION_ARROW_INTERVAL_METERS, sequence += 1
  ) {
    const placement = pointAndAxisAlongLine(lane.coordinates, distance);
    if (!placement) continue;
    const rings = arrowRingsAt('through', placement.point, placement.axis);
    if (ringsOverlapControl(rings, controlFeatures)) {
      diagnostics.push(
        diagnostic(
          'info',
          lane.id,
          road.osmWayIds,
          'direction-arrow-control-conflict',
          '默认直行箭头会压住斑马线或停止线，已跳过该位置。',
          placement.point,
        ),
      );
      continue;
    }
    for (let part = 0; part < rings.length; part += 1)
      features.push({
        type: 'Feature',
        properties: {
          native_id: `direction-arrow:${lane.id}:${sequence}:${part}`,
          road_id: road.id,
          lane_id: lane.id,
          osm_way_ids: road.osmWayIds.join(','),
          direction: road.direction,
          lane_index: lane.index,
          maneuver: 'through',
          sequence,
          distance_along_lane_meters: Math.round(distance * 10) / 10,
          placement_interval_meters: DIRECTION_ARROW_INTERVAL_METERS,
          provenance: 'native-road-direction-arrow/v1',
        },
        geometry: { type: 'Polygon', coordinates: [rings[part]] },
      });
  }
  return features;
}

function ringsOverlapControl(rings, controls) {
  return rings.some((ring) => controls.some((feature) => ringsOverlap(ring, feature.geometry.coordinates[0])));
}
function ringsOverlap(first, second) {
  const bounds = (ring) => [
    Math.min(...ring.map((point) => point[0])),
    Math.min(...ring.map((point) => point[1])),
    Math.max(...ring.map((point) => point[0])),
    Math.max(...ring.map((point) => point[1])),
  ];
  const a = bounds(first);
  const b = bounds(second);
  if (a[0] > b[2] || a[2] < b[0] || a[1] > b[3] || a[3] < b[1]) return false;
  if (first.some((point) => pointInPolygon(point, second)) || second.some((point) => pointInPolygon(point, first)))
    return true;
  return first
    .slice(1)
    .some((point, index) =>
      second.slice(1).some((other, otherIndex) => segmentsIntersect(first[index], point, second[otherIndex], other)),
    );
}

function compileSidewalkSurfaces(model, diagnostics, junctionPlans, options = {}) {
  const features = [];
  const byWay = new Map();
  for (const road of model.roads) {
    const key = road.segmentId;
    if (!byWay.has(key)) byWay.set(key, []);
    byWay.get(key).push(road);
  }
  for (const [wayKey, directions] of byWay) {
    const forward = directions.find((road) => road.direction === 'forward') || directions[0];
    const backward = directions.find((road) => road.id !== forward.id);
    const totalWidth = directions.reduce((sum, road) => sum + road.widthMeters, 0);
    const sides = [
      ['left', forward.sidewalkLeft || Boolean(backward?.sidewalkRight)],
      ['right', forward.sidewalkRight || Boolean(backward?.sidewalkLeft)],
    ];
    const cluster = clusterForRoad(forward, options) || (backward ? clusterForRoad(backward, options) : null);
    const center = cluster ? clusterCenter(cluster, junctionPlans) : null;
    for (const [side, enabled] of sides) {
      if (!enabled) continue;
      const centerline = cluster
        ? trimLineAtComplexCluster(forward.centerline, forward.sourceNodeIds, junctionPlans, cluster, center)
        : trimLineAtJunctions(forward.centerline, forward.sourceNodeIds, junctionPlans);
      const ring = sidewalkRing(
        centerline,
        totalWidth / 2,
        totalWidth / 2 + DEFAULT_SIDEWALK_WIDTH_METERS,
        side === 'left' ? 1 : -1,
      );
      if (!ring) {
        diagnostics.push(
          diagnostic(
            'warning',
            forward.id,
            forward.osmWayIds,
            'invalid-sidewalk-surface',
            '无法为该道路生成连续人行道面。',
            forward.centerline[0],
          ),
        );
        continue;
      }
      const sidewalkId = forward.segmentId.endsWith('/0')
        ? `sidewalk:way/${forward.osmWayIds.join(',')}:${side}`
        : `sidewalk:${wayKey}:${side}`;
      features.push({
        type: 'Feature',
        properties: {
          native_id: sidewalkId,
          cluster_id: cluster?.id || null,
          osm_way_ids: forward.osmWayIds.join(','),
          source_road_id: forward.sourceRoadId,
          side,
          width_m: DEFAULT_SIDEWALK_WIDTH_METERS,
          directional_road_ids: directions.map((road) => road.id).join(','),
          provenance: 'native-road-sidewalk/v1',
          override_ids: directions.flatMap((road) => road.appliedOverrideIds).join(','),
        },
        geometry: { type: 'Polygon', coordinates: [ring] },
      });
    }
  }
  features.push(...compileSidewalkCorners(model, junctionPlans, options));
  return features;
}

function compileSidewalkCorners(model, junctionPlans, options = {}) {
  const result = [];
  for (const [nodeId, plan] of junctionPlans) {
    if (plan.clusterId && activeComplexCluster(options, plan.clusterId)) continue;
    const candidates = [];
    for (const approach of plan.approaches) {
      const directions = model.roads.filter((road) => road.segmentId === approach.segmentId);
      const forward = directions.find((road) => road.direction === 'forward') || directions[0];
      if (!forward) continue;
      const outwardIsForward = forward.sourceNodeIds[0] === nodeId;
      const sideStates = outwardIsForward
        ? { left: forward.sidewalkLeft, right: forward.sidewalkRight }
        : { left: forward.sidewalkRight, right: forward.sidewalkLeft };
      const cutback = pointAlongLine(approach.line, plan.cutbackMeters);
      if (!cutback) continue;
      const heading = headingAtEndpoint(approach.line);
      const halfWidth = approach.widthMeters / 2;
      for (const [side, enabled] of Object.entries(sideStates)) {
        if (!enabled) continue;
        // offsetLine's positive normal is driver's left, which is heading -90
        // in this north-based heading convention.
        const sideHeading = heading + (side === 'left' ? -90 : 90);
        candidates.push({
          wayKey: approach.segmentId,
          sourceWayKey: forward.osmWayIds.join(','),
          side,
          outwardHeading: heading,
          normalDegrees: sideHeading,
          curb: offsetCoordinate(cutback, sideHeading, halfWidth),
          outer: offsetCoordinate(cutback, sideHeading, halfWidth + DEFAULT_SIDEWALK_WIDTH_METERS),
        });
      }
    }
    candidates.sort((a, b) => angleAround(plan.node, a.curb) - angleAround(plan.node, b.curb));
    for (let index = 0; index < candidates.length; index += 1) {
      const first = candidates[index];
      const second = candidates[(index + 1) % candidates.length];
      if (first.wayKey === second.wayKey) continue;
      const continuation = isStraightSidewalkContinuation(first, second);
      if (first.sourceWayKey === second.sourceWayKey && !continuation) continue;
      // A split-through road has two approaches at this node. Its pedestrian
      // strip is a direct continuation, not a curb corner. Treating it as a
      // curve creates the oversized outer lobe seen at T junctions.
      const ring = continuation
        ? [first.curb, first.outer, second.outer, second.curb, first.curb]
        : roundedSidewalkCorner(plan.node, first, second);
      if (hasSelfIntersection(ring)) continue;
      if (continuation && cornerFallsIntoOtherApproach(ring, first.sourceWayKey, plan.approaches)) continue;
      result.push({
        type: 'Feature',
        properties: {
          native_id: `sidewalk-corner:node/${nodeId}:${first.wayKey}:${first.side}->${second.wayKey}:${second.side}`,
          osm_node_id: nodeId,
          kind: continuation ? 'continuation' : 'corner',
          width_m: DEFAULT_SIDEWALK_WIDTH_METERS,
          provenance: continuation ? 'native-road-sidewalk-continuation/v1' : 'native-road-sidewalk-corner/v1',
        },
        geometry: { type: 'Polygon', coordinates: [ring] },
      });
    }
  }
  return result;
}

function roundedSidewalkCorner(node, first, second) {
  // Keep the established vehicle curb geometry, then derive the outer edge
  // from it. Independent Bezier curves drift apart and leave asphalt exposed
  // between the junction and pedestrian layers.
  const curbForward = roundedCorner(node, first.curb, second.curb, first.outwardHeading, second.outwardHeading) || [
    first.curb,
    second.curb,
  ];
  // Construct the outside edge from the same tangent-support rule. A linear
  // point-by-point offset changes the curvature and makes the two boundaries
  // visibly disagree at the middle of the corner.
  const outerForward =
    roundedCorner(node, first.outer, second.outer, first.outwardHeading, second.outwardHeading) ||
    offsetCornerArc(curbForward, first.curb, first.outer, second.curb, second.outer);
  const curbArc = [...curbForward].reverse();
  return [
    first.curb,
    first.outer,
    ...outerForward.slice(1, -1),
    second.outer,
    second.curb,
    ...curbArc.slice(1, -1),
    first.curb,
  ];
}

function offsetCornerArc(curbArc, firstCurb, firstOuter, secondCurb, secondOuter) {
  return curbArc.map((point, index) => {
    const ratio = curbArc.length === 1 ? 0 : index / (curbArc.length - 1);
    const firstOffset = [firstOuter[0] - firstCurb[0], firstOuter[1] - firstCurb[1]];
    const secondOffset = [secondOuter[0] - secondCurb[0], secondOuter[1] - secondCurb[1]];
    return [
      point[0] + firstOffset[0] + (secondOffset[0] - firstOffset[0]) * ratio,
      point[1] + firstOffset[1] + (secondOffset[1] - firstOffset[1]) * ratio,
    ];
  });
}

function samePhysicalSide(first, second) {
  const radians = ((first.normalDegrees - second.normalDegrees) * Math.PI) / 180;
  return Math.cos(radians) >= 0.98;
}

function isStraightSidewalkContinuation(first, second) {
  if (first.sourceWayKey !== second.sourceWayKey || !samePhysicalSide(first, second)) return false;
  const radians = ((first.outwardHeading - second.outwardHeading) * Math.PI) / 180;
  return Math.cos(radians) <= -0.98;
}

function cornerFallsIntoOtherApproach(ring, sourceWayKey, approaches) {
  const vertices = ring.slice(0, -1);
  const center = vertices.reduce(
    (sum, point) => [sum[0] + point[0] / vertices.length, sum[1] + point[1] / vertices.length],
    [0, 0],
  );
  return approaches
    .filter((approach) => approach.sourceWayKey !== sourceWayKey)
    .some((approach) => {
      const carriageway = roadRing(approach.line, approach.widthMeters);
      return carriageway && pointInPolygon(center, carriageway);
    });
}

function validateConnectorContainment(connectors, junctionFeatures, diagnostics) {
  const junctionByNode = new Map();
  for (const feature of junctionFeatures) {
    if (feature.properties.osm_node_ids)
      for (const nodeId of String(feature.properties.osm_node_ids).split(',')) junctionByNode.set(nodeId, feature);
    else if (feature.properties.osm_node_id) junctionByNode.set(feature.properties.osm_node_id, feature);
  }
  for (const connector of connectors) {
    const junction = junctionByNode.get(connector.properties.node_id);
    if (!junction) continue;
    if (junction.properties.kind === 'cluster') continue;
    const ring = junction.geometry.coordinates[0];
    if (
      !connector.geometry.coordinates.every((point) =>
        pointInOrNearPolygon(point, ring, CONNECTOR_BOUNDARY_TOLERANCE_METERS),
      )
    ) {
      diagnostics.push(
        diagnostic(
          'warning',
          connector.properties.connection_id,
          [connector.properties.node_id],
          'connector-outside-junction',
          '转向路径有部分落在路口面外，请检查道路截面或转向连接。',
          connector.geometry.coordinates[0],
        ),
      );
    }
  }
}

function pointInPolygon(point, ring) {
  for (let index = 1; index < ring.length; index += 1)
    if (pointOnSegment(point, ring[index - 1], ring[index])) return true;
  let inside = false;
  for (let index = 0, previous = ring.length - 1; index < ring.length; previous = index++) {
    const a = ring[index];
    const b = ring[previous];
    const intersect =
      a[1] > point[1] !== b[1] > point[1] && point[0] < ((b[0] - a[0]) * (point[1] - a[1])) / (b[1] - a[1]) + a[0];
    if (intersect) inside = !inside;
  }
  return inside;
}
function pointInOrNearPolygon(point, ring, toleranceMeters) {
  return (
    pointInPolygon(point, ring) ||
    ring.slice(1).some((end, index) => distancePointToSegmentMeters(point, ring[index], end) <= toleranceMeters)
  );
}
function distancePointToSegmentMeters(point, start, end) {
  const localPoint = project(point, start);
  const localEnd = project(end, start);
  const lengthSquared = localEnd[0] ** 2 + localEnd[1] ** 2;
  if (lengthSquared < 0.0001) return Math.hypot(...localPoint);
  const ratio = Math.max(0, Math.min(1, (localPoint[0] * localEnd[0] + localPoint[1] * localEnd[1]) / lengthSquared));
  return Math.hypot(localPoint[0] - localEnd[0] * ratio, localPoint[1] - localEnd[1] * ratio);
}
function pointOnSegment(point, a, b) {
  const cross = (point[0] - a[0]) * (b[1] - a[1]) - (point[1] - a[1]) * (b[0] - a[0]);
  if (Math.abs(cross) > 1e-12) return false;
  return (
    point[0] >= Math.min(a[0], b[0]) - 1e-12 &&
    point[0] <= Math.max(a[0], b[0]) + 1e-12 &&
    point[1] >= Math.min(a[1], b[1]) - 1e-12 &&
    point[1] <= Math.max(a[1], b[1]) + 1e-12
  );
}

// `complexControls` carries the crosswalks and stop bars the complex-junction
// templates already emitted. Ordinary controls cannot be passed here: they are
// placed *from* these lane centerlines, so only the template-generated ones
// exist this early.
function compileLaneCenterlines(model, diagnostics, junctionPlans, options = {}, complexControls = {}) {
  const features = [];
  const controlFeatures = [...(complexControls.crosswalks || []), ...(complexControls.stopLines || [])];
  const byRoadId = new Map();
  const markingByRoadId = new Map();
  const clusters = options.junctionTemplates?.enabled ? options.junctionTemplates.clusters || [] : [];
  const clusterByNode = new Map(
    clusters.flatMap((cluster) => cluster.nodeIds.map((nodeId) => [String(nodeId), cluster])),
  );
  const clusterCenters = new Map(clusters.map((cluster) => [cluster.id, clusterCenter(cluster, junctionPlans)]));
  for (const road of model.roads) {
    const lanes = [];
    const markingLanes = [];
    const laneWidth = road.widthMeters / road.laneCount;
    const siblings = model.roads.filter((item) => item.segmentId === road.segmentId);
    const opposite = siblings.find((item) => item.id !== road.id);
    const boundaryCluster =
      clusterByNode.get(String(road.sourceNodeIds[0])) || clusterByNode.get(String(road.sourceNodeIds.at(-1)));
    const internalCluster = boundaryCluster && roadInternalToCluster(road, boundaryCluster);
    const clippedRoadLine =
      boundaryCluster?.template === 'complex-junction-v1'
        ? trimLineAtComplexCluster(
            road.centerline,
            road.sourceNodeIds,
            junctionPlans,
            boundaryCluster,
            clusterCenters.get(boundaryCluster.id),
          )
        : trimLineAtJunctions(road.centerline, road.sourceNodeIds, junctionPlans);
    // OSM centerline is the shared carriageway center. On a two-way road,
    // offset each directed carriageway to its own side before placing lanes.
    const carriagewayOffset = opposite
      ? road.direction === 'forward'
        ? -opposite.widthMeters / 2
        : -road.widthMeters / 2
      : 0;
    for (let index = 0; index < road.laneCount; index += 1) {
      // OSM `turn:lanes` is ordered from left to right. Keep lane 1 on the
      // driver's left so tag positions and generated lane IDs have one meaning.
      const offset = carriagewayOffset + (road.widthMeters / 2 - laneWidth * (index + 0.5));
      const coordinates = offsetLine(trimLineAtJunctions(road.centerline, road.sourceNodeIds, junctionPlans), offset);
      const publishedCoordinates = offsetLine(clippedRoadLine, offset);
      if (!coordinates || !publishedCoordinates) {
        diagnostics.push(
          diagnostic(
            'error',
            road.id,
            road.osmWayIds,
            'invalid-lane-centerline',
            '无法为该道路生成车道中心线。',
            road.centerline[0],
          ),
        );
        continue;
      }
      const lane = { id: `lane:${road.id}:${index + 1}`, roadId: road.id, index: index + 1, coordinates };
      lanes.push(lane);
      // Only the published geometry stops at the crossing. `coordinates` stays
      // whole because connectors are derived from it; a lane that ends at the
      // stop bar would otherwise break every turn path through the junction.
      const visibleCoordinates =
        boundaryCluster?.template === 'complex-junction-v1'
          ? trimLaneOutsideControls(
              publishedCoordinates,
              controlFeatures,
              LANE_CENTERLINE_PROBE_WIDTH_METERS,
              clusterCenters.get(boundaryCluster.id),
            )
          : publishedCoordinates;
      if (!visibleCoordinates) {
        diagnostics.push(
          diagnostic(
            'warning',
            road.id,
            road.osmWayIds,
            'lane-centerline-fully-inside-control',
            '该车道中心线整体落在斑马线或停止线内，已按未裁剪几何发布。',
            publishedCoordinates[0],
          ),
        );
      }
      // Lane markings are laid out along this line. Feeding it the clipped
      // geometry is what keeps separators and arrows from being painted *past*
      // a crossing: control avoidance only stops them landing *on* one.
      markingLanes.push({ ...lane, coordinates: visibleCoordinates || publishedCoordinates });
      features.push({
        type: 'Feature',
        properties: {
          native_id: lane.id,
          road_id: road.id,
          lane_index: lane.index,
          cluster_id: boundaryCluster?.id || null,
          cluster_internal: Boolean(internalCluster),
          cluster_preview_hidden: Boolean(internalCluster),
          cluster_boundary_clipped: Boolean(boundaryCluster && !internalCluster),
          control_clipped: laneWasClipped(publishedCoordinates, visibleCoordinates),
          source: 'native-road-lane-centerline/v3-control-clipped',
        },
        geometry: { type: 'LineString', coordinates: visibleCoordinates || publishedCoordinates },
      });
    }
    byRoadId.set(road.id, lanes);
    markingByRoadId.set(road.id, markingLanes);
  }
  for (const cluster of clusters) {
    const clusterNodes = new Set(cluster.nodeIds.map(String));
    const clusterCoordinates = [...clusterNodes].map((nodeId) => junctionPlans.get(nodeId)?.node).filter(Boolean);
    const compositeCenter = clusterCoordinates.length
      ? clusterCoordinates.reduce(
          (sum, point) => [
            sum[0] + point[0] / clusterCoordinates.length,
            sum[1] + point[1] / clusterCoordinates.length,
          ],
          [0, 0],
        )
      : null;
    const corridors = [];
    for (const [nodeId, plan] of junctionPlans) {
      if (!clusterNodes.has(String(nodeId))) continue;
      for (const approach of plan.approaches) {
        const end = approach.line.at(-1);
        if (
          [...clusterNodes].some(
            (candidate) =>
              candidate !== String(nodeId) &&
              distanceMeters(end, junctionPlans.get(candidate)?.node || [Infinity, Infinity]) < 3,
          )
        )
          continue;
        const heading = ((headingAtEndpoint(approach.line) + 180) % 360) - 180;
        corridors.push({ nodeId, heading, approach, plan });
      }
    }
    for (const corridor of corridors) {
      const approach = corridor.approach;
      const plan = corridor.plan;
      const outerRadius = complexJunctionMetrics(cluster).approachOuterRadius;
      const length = Math.min(
        distanceAlongLineToRadius(approach.line, compositeCenter, outerRadius),
        lineLengthMeters(approach.line),
      );
      if (length < 12) continue;
      const line = approach.line;
      const outer = pointAlongLine(line, Math.max(0, length));
      const inner = pointAlongLine(
        line,
        Math.min(Math.max(3, Number(cluster.coreRadiusMeters || 28) * 0.14), Math.max(3, length - 8)),
      );
      const corridorRoads = approach.roadIds
        .map((roadId) => model.roads.find((road) => road.id === roadId))
        .filter(Boolean);
      const incoming = corridorRoads.some((road) => String(road.sourceNodeIds.at(-1)) === String(corridor.nodeId));
      const count = Math.max(
        1,
        corridorRoads.reduce((sum, road) => sum + road.laneCount, 0),
      );
      const laneWidth = approach.widthMeters / count;
      const axis = project(inner, outer);
      const total = Math.hypot(...axis);
      if (!total) continue;
      const normalized = [axis[0] / total, axis[1] / total];
      const across = [-normalized[1], normalized[0]];
      for (let index = 0; index < count; index += 1) {
        const offset = approach.widthMeters / 2 - laneWidth * (index + 0.5);
        const start = unproject([across[0] * offset, across[1] * offset], outer);
        const end = unproject([across[0] * offset, across[1] * offset], inner);
        const maneuver = incoming ? (index === 0 ? 'left' : index === count - 1 ? 'right' : 'through') : 'outbound';
        // Preview lanes are laid out radially from the outer radius inwards, so
        // an untrimmed one runs straight over the arm crossing. Stop it at the
        // first control: incoming lanes land on the stop bar, outgoing lanes on
        // the far edge of the crossing.
        const visible = trimLaneOutsideControls(
          [start, end],
          controlFeatures,
          LANE_CENTERLINE_PROBE_WIDTH_METERS,
          compositeCenter,
        );
        features.push({
          type: 'Feature',
          properties: {
            native_id: `cluster-approach-lane:${cluster.id}:${approach.segmentId}:${index + 1}`,
            road_id: corridorRoads[0]?.id || null,
            cluster_id: cluster.id,
            cluster_preview: true,
            incoming,
            lane_index: index + 1,
            maneuver,
            control_clipped: laneWasClipped([start, end], visible),
            source: 'native-road-junction-cluster-lane/v4-control-clipped',
          },
          geometry: { type: 'LineString', coordinates: visible || [start, end] },
        });
      }
    }
  }
  return { features, byRoadId, markingByRoadId };
}

function cubicTurnCurve(start, end, startHeading, endHeading, radius, turn, center) {
  const reach = turn === 'right' ? Math.max(5, radius * 0.75) : Math.max(9, radius * 1.35);
  const first = offsetCoordinate(start, startHeading, reach);
  const second = offsetCoordinate(end, endHeading, reach);
  const points = [];
  for (let index = 0; index <= 18; index += 1) {
    const t = index / 18;
    const inverse = 1 - t;
    points.push([
      inverse ** 3 * start[0] + 3 * inverse ** 2 * t * first[0] + 3 * inverse * t ** 2 * second[0] + t ** 3 * end[0],
      inverse ** 3 * start[1] + 3 * inverse ** 2 * t * first[1] + 3 * inverse * t ** 2 * second[1] + t ** 3 * end[1],
    ]);
  }
  return points.every((point) => point.every(Number.isFinite)) ? points : [start, center, end];
}

function compileConnectors(model, lanes, diagnostics, overrides, junctionPlans) {
  const features = [];
  const movements = [];
  for (const connection of model.connections.filter((item) => item.enabled)) {
    const fromRoad = model.roads.find((road) => road.id === endpointRoadId(model, connection.fromEndpointId));
    const toRoad = model.roads.find((road) => road.id === endpointRoadId(model, connection.toEndpointId));
    const fromLanes = lanes.byRoadId.get(fromRoad?.id) || [];
    const toLanes = lanes.byRoadId.get(endpointRoadId(model, connection.toEndpointId)) || [];
    if (!fromLanes.length || !toLanes.length) {
      diagnostics.push(
        diagnostic(
          'warning',
          connection.id,
          [connection.nodeId],
          'connector-missing-lane',
          '转向连接缺少可用车道中心线。',
          endpointCoordinate(model, connection.fromEndpointId),
        ),
      );
      continue;
    }
    for (let index = 0; index < fromLanes.length; index += 1) {
      const turn = connectionTurn(fromRoad, toRoad);
      const defaultTargetIndex = targetLaneIndex(turn, index, fromLanes.length, toLanes.length);
      const defaultFromLane = fromLanes[index];
      const defaultToLane = toLanes[defaultTargetIndex];
      const override = laneOverride(overrides, defaultFromLane.id, defaultToLane.id);
      if ((!laneAllowsTurn(fromRoad, index, turn) && override?.enabled !== true) || override?.enabled === false)
        continue;
      const from = defaultFromLane.coordinates.at(-1);
      const to = defaultToLane.coordinates[0];
      const plan = junctionPlans.get(connection.nodeId);
      // Cross intersections retain the earlier center-node curve while T junctions
      // use lane tangents so their through movement does not bow toward the stem.
      const coordinates =
        plan?.segmentIds.size === 4
          ? quadraticCurve(from, endpointCoordinate(model, connection.fromEndpointId), to, 12)
          : connectorCurve(defaultFromLane.coordinates, defaultToLane.coordinates, turn);
      const length = lineLengthMeters(coordinates);
      const id = `movement:${connection.id}:${defaultFromLane.id}->${defaultToLane.id}`;
      const provenance = override ? `override:${override.id}` : connection.provenance;
      const connectorId = `connector:${id}`;
      const geometryStatus = length < 0.4 ? 'continuous' : length > 80 ? 'deferred-too-long' : 'connector';
      const movement = {
        id,
        connectorId,
        connectionId: connection.id,
        nodeId: connection.nodeId,
        fromRoadId: fromRoad.id,
        toRoadId: defaultToLane.roadId,
        fromLaneId: defaultFromLane.id,
        toLaneId: defaultToLane.id,
        turn,
        provenance,
        appliedOverrideIds: override ? [override.id] : [],
        geometryPublished: geometryStatus === 'connector',
        geometryStatus,
      };
      if (length < 0.4) {
        movements.push(movement);
        continue;
      }
      if (length > 80) {
        diagnostics.push(
          diagnostic(
            'warning',
            connection.id,
            [connection.nodeId],
            'connector-too-long',
            '转向路径超过 80 米，未发布几何；请检查路口拓扑或人工连接。',
            from,
          ),
        );
        movements.push(movement);
        continue;
      }
      const cluster = plan?.clusterId || null;
      features.push({
        type: 'Feature',
        properties: {
          native_id: connectorId,
          movement_id: id,
          connection_id: connection.id,
          node_id: connection.nodeId,
          cluster_id: cluster,
          cluster_internal: Boolean(cluster),
          from_lane_id: defaultFromLane.id,
          to_lane_id: defaultToLane.id,
          turn,
          provenance,
        },
        geometry: { type: 'LineString', coordinates },
      });
      movements.push(movement);
    }
  }
  return { features, movements };
}
function laneOverride(overrides, fromLaneId, toLaneId) {
  return overrides.overrides.find(
    (item) => item.kind === 'lane-connection' && item.fromLaneId === fromLaneId && item.toLaneId === toLaneId,
  );
}

function endpointRoadId(model, endpointId) {
  return model.endpoints.find((endpoint) => endpoint.id === endpointId)?.roadId;
}
function endpointCoordinate(model, endpointId) {
  return model.endpoints.find((endpoint) => endpoint.id === endpointId)?.coordinate;
}
function connectionTurn(fromRoad, toRoad) {
  if (!fromRoad || !toRoad) return 'unknown';
  const incoming = headingDegrees(fromRoad.centerline.at(-2), fromRoad.centerline.at(-1));
  const outgoing = headingDegrees(toRoad.centerline[0], toRoad.centerline[1]);
  const delta = ((outgoing - incoming + 540) % 360) - 180;
  if (Math.abs(delta) >= 150) return 'uturn';
  if (Math.abs(delta) <= 30) return 'through';
  return delta > 0 ? 'right' : 'left';
}
function laneAllowsTurn(road, zeroIndex, turn) {
  if (!road) return true;
  const tag = road.tags[`turn:lanes:${road.direction}`] ?? road.tags['turn:lanes'];
  if (!tag) return true;
  const lanes = String(tag)
    .split('|')
    .map((lane) =>
      lane
        .split(';')
        .map((value) => value.trim().replace('slight_', ''))
        .filter(Boolean),
    );
  const allowed = lanes[zeroIndex];
  return !allowed || allowed.includes(turn) || (turn === 'uturn' && allowed.includes('reverse'));
}
function targetLaneIndex(turn, sourceIndex, sourceCount, targetCount) {
  if (turn === 'left') return 0;
  if (turn === 'right') return targetCount - 1;
  if (turn === 'uturn') return 0;
  return Math.min(
    targetCount - 1,
    Math.round((sourceIndex / Math.max(1, sourceCount - 1)) * Math.max(0, targetCount - 1)),
  );
}
function connectorCurve(incoming, outgoing, turn) {
  const start = incoming.at(-1);
  const end = outgoing[0];
  if (turn === 'through') return lineCurve(start, end, 12);
  const incomingHeading = headingDegrees(incoming.at(-2), start);
  const outgoingHeading = headingDegrees(end, outgoing[1]);
  const chord = distanceMeters(start, end);
  const incomingSpan = distanceMeters(incoming.at(-2), start);
  const outgoingSpan = distanceMeters(end, outgoing[1]);
  const tangentIntersection = intersectTangentRays(start, end, incomingHeading, outgoingHeading);
  const fallbackDistance = Math.min(8, Math.max(0.75, Math.min(chord * 0.42, incomingSpan * 0.8, outgoingSpan * 0.8)));
  const firstDistance =
    tangentIntersection && tangentIntersection.incoming >= 0
      ? Math.min(tangentIntersection.incoming, Math.min(8, Math.max(0.75, incomingSpan * 2.4))) / 3
      : fallbackDistance;
  const secondDistance =
    tangentIntersection && tangentIntersection.outgoing >= 0
      ? Math.min(tangentIntersection.outgoing, Math.min(8, Math.max(0.75, outgoingSpan * 2.4))) / 3
      : fallbackDistance;
  const firstControl = offsetCoordinate(start, incomingHeading, firstDistance);
  const secondControl = offsetCoordinate(end, outgoingHeading + 180, secondDistance);
  return cubicBezier(start, firstControl, secondControl, end, 12);
}

function intersectTangentRays(start, end, incomingHeading, outgoingHeading) {
  const incoming = headingVector(incomingHeading);
  const outgoing = headingVector(outgoingHeading);
  const delta = project(end, start);
  const cross = incoming[0] * outgoing[1] - incoming[1] * outgoing[0];
  if (Math.abs(cross) < 1e-6) return null;
  return {
    incoming: (delta[0] * outgoing[1] - delta[1] * outgoing[0]) / cross,
    outgoing: (delta[0] * incoming[1] - delta[1] * incoming[0]) / cross,
  };
}

function lineCurve(start, end, segments) {
  return Array.from({ length: segments + 1 }, (_, index) => interpolate(start, end, index / segments));
}

function cubicBezier(a, firstControl, secondControl, b, segments) {
  const result = [];
  for (let index = 0; index <= segments; index += 1) {
    const t = index / segments;
    const u = 1 - t;
    result.push([
      u ** 3 * a[0] + 3 * u * u * t * firstControl[0] + 3 * u * t * t * secondControl[0] + t ** 3 * b[0],
      u ** 3 * a[1] + 3 * u * u * t * firstControl[1] + 3 * u * t * t * secondControl[1] + t ** 3 * b[1],
    ]);
  }
  return result;
}

function quadraticCurve(a, control, b, segments) {
  const result = [];
  for (let index = 0; index <= segments; index += 1) {
    const t = index / segments;
    const u = 1 - t;
    result.push([
      u * u * a[0] + 2 * u * t * control[0] + t * t * b[0],
      u * u * a[1] + 2 * u * t * control[1] + t * t * b[1],
    ]);
  }
  return result;
}

function offsetLine(line, offsetMeters) {
  if (line.length < 2) return null;
  const origin = line[0];
  const points = line.map((point) => project(point, origin));
  const result = [];
  for (let index = 0; index < points.length; index += 1) {
    const previous = points[Math.max(0, index - 1)];
    const next = points[Math.min(points.length - 1, index + 1)];
    const dx = next[0] - previous[0];
    const dy = next[1] - previous[1];
    const length = Math.hypot(dx, dy);
    if (length < 0.01) return null;
    result.push(
      unproject(
        [points[index][0] - (dy / length) * offsetMeters, points[index][1] + (dx / length) * offsetMeters],
        origin,
      ),
    );
  }
  return result;
}

function lineLengthMeters(line) {
  return line.slice(1).reduce((sum, point, index) => {
    const previous = line[index];
    const dx = (point[0] - previous[0]) * 111320 * Math.cos((point[1] * Math.PI) / 180);
    const dy = (point[1] - previous[1]) * 111320;
    return sum + Math.hypot(dx, dy);
  }, 0);
}
function polygonAreaMeters(ring) {
  if (ring.length < 3) return 0;
  const origin = ring[0];
  const points = ring.map((point) => project(point, origin));
  let twiceArea = 0;
  for (let index = 0; index < points.length; index += 1) {
    const next = points[(index + 1) % points.length];
    twiceArea += points[index][0] * next[1] - next[0] * points[index][1];
  }
  return Math.abs(twiceArea) / 2;
}

function compileJunctionSurfaces(model, junctionPlans, connectors, movements, diagnostics, options = {}) {
  const result = [];
  const complexClusters = new Set(
    (options.junctionTemplates?.enabled ? options.junctionTemplates.clusters || [] : [])
      .filter((cluster) => cluster.template === 'complex-junction-v1')
      .map((cluster) => cluster.id),
  );
  for (const [nodeId, plan] of junctionPlans) {
    if (plan.clusterId && complexClusters.has(plan.clusterId)) continue;
    const { segmentIds, node, approaches, cutbackMeters, boundary } = plan;
    const junctionConnectors = connectors.filter((feature) => feature.properties.node_id === nodeId);
    const junctionMovements = movements.filter((movement) => movement.nodeId === nodeId);
    if (boundary.length < 3 || !junctionMovements.length) {
      diagnostics.push(
        diagnostic(
          'warning',
          `junction:node/${nodeId}`,
          [nodeId],
          'junction-surface-deferred',
          '路口缺少足够的截面或转向路径，暂不生成路口面。',
          node,
        ),
      );
      continue;
    }
    const approachAreaMeters = polygonAreaMeters(boundary);
    let ring = [...boundary, boundary[0]];
    let boundaryMode = plan.boundaryMode || 'approach-envelope';
    if (
      hasSelfIntersection(ring) ||
      !junctionConnectors.every((feature) =>
        feature.geometry.coordinates.every((point) =>
          pointInOrNearPolygon(point, ring, CONNECTOR_BOUNDARY_TOLERANCE_METERS),
        ),
      )
    ) {
      const envelope = convexHull([
        ...boundary,
        ...junctionConnectors.flatMap((feature) => feature.geometry.coordinates),
      ]);
      ring = [...envelope, envelope[0]];
      boundaryMode = 'connector-convex-fallback';
    }
    if (hasSelfIntersection(ring)) {
      diagnostics.push(
        diagnostic(
          'error',
          `junction:node/${nodeId}`,
          [nodeId],
          'invalid-junction-surface',
          '路口截面边界发生自相交，未发布路口面。请检查道路方向或路口拓扑。',
          node,
        ),
      );
      continue;
    }
    const surfaceAreaMeters = polygonAreaMeters(ring);
    const expansionRatio = approachAreaMeters > 0 ? surfaceAreaMeters / approachAreaMeters : null;
    result.push({
      type: 'Feature',
      properties: {
        native_id: `junction:node/${nodeId}`,
        osm_node_id: nodeId,
        kind: segmentIds.size === 3 ? 't' : 'cross',
        source_road_ids: approaches.flatMap((approach) => approach.roadIds).join(','),
        cutback_m: cutbackMeters,
        movement_count: junctionMovements.length,
        connector_count: junctionConnectors.length,
        boundary_mode: boundaryMode,
        template: plan.template || null,
        template_reference: plan.templateReference || null,
        approach_area_m2: Math.round(approachAreaMeters * 10) / 10,
        surface_area_m2: Math.round(surfaceAreaMeters * 10) / 10,
        expansion_ratio: expansionRatio === null ? null : Math.round(expansionRatio * 100) / 100,
        rule: plan.template ? 'junction-cross-template/v1' : 'junction-shared-cutback/v4-shared-node-split',
      },
      geometry: { type: 'Polygon', coordinates: [ring] },
    });
    if (boundaryMode === 'connector-convex-fallback')
      diagnostics.push(
        diagnostic(
          'warning',
          `junction:node/${nodeId}`,
          [nodeId],
          'junction-connector-envelope-fallback',
          '路口面需要按转向路径的凸包兜底生成；请检查外缘和路缘与步行带是否符合实际。',
          node,
        ),
      );
    if (plan.boundaryFallbacks)
      diagnostics.push(
        diagnostic(
          'warning',
          `junction:node/${nodeId}`,
          [nodeId],
          'junction-rounded-corner-fallback',
          '部分路口圆角无法按道路边缘切线安全构造，已对该角使用确定性的直线回退。',
          node,
        ),
      );
    if (!plan.clusterId)
      diagnostics.push(
        diagnostic(
          'info',
          `junction:node/${nodeId}`,
          [nodeId],
          'ordinary-junction-surface',
          '已按道路截面与转向路径生成普通路口面。',
          node,
        ),
      );
  }
  for (const cluster of options.junctionTemplates?.enabled ? options.junctionTemplates.clusters || [] : []) {
    if (cluster.template === 'complex-junction-v1') continue;
    const clusterNodes = new Set(cluster.nodeIds.map(String));
    const members = result.filter((feature) => clusterNodes.has(String(feature.properties.osm_node_id)));
    if (members.length < 2) continue;
    const points = [];
    const clusterCoordinates = [...clusterNodes].map((nodeId) => junctionPlans.get(nodeId)?.node).filter(Boolean);
    const clusterCenter = clusterCoordinates.reduce(
      (sum, point) => [sum[0] + point[0] / clusterCoordinates.length, sum[1] + point[1] / clusterCoordinates.length],
      [0, 0],
    );
    for (let index = 0; index < 8; index += 1) points.push(offsetCoordinate(clusterCenter, index * 45, 12));
    for (const [nodeId, plan] of junctionPlans) {
      if (!clusterNodes.has(String(nodeId))) continue;
      for (const approach of plan.approaches) {
        const end = approach.line.at(-1);
        if (
          [...clusterNodes].some(
            (candidate) =>
              candidate !== String(nodeId) &&
              distanceMeters(end, junctionPlans.get(candidate)?.node || [Infinity, Infinity]) < 3,
          )
        )
          continue;
        const cutback = pointAlongLine(
          approach.line,
          Math.min(plan.cutbackMeters, Math.max(12, cluster.approachLengthMeters * 0.5)),
        );
        const heading = headingAtEndpoint(approach.line);
        const half = approach.widthMeters / 2;
        points.push(offsetCoordinate(cutback, heading + 90, half), offsetCoordinate(cutback, heading - 90, half));
      }
      const node = plan.node;
      for (let index = 0; index < 8; index += 1) points.push(offsetCoordinate(node, index * 45, 9));
    }
    const hull = convexHull(points);
    if (hull.length < 3) continue;
    const ring = roundedHull(hull, 0.22);
    const memberIds = new Set(members.map((feature) => feature.properties.native_id));
    for (let index = result.length - 1; index >= 0; index -= 1)
      if (memberIds.has(result[index].properties.native_id)) result.splice(index, 1);
    result.push({
      type: 'Feature',
      properties: {
        native_id: `junction-cluster:${cluster.id}`,
        osm_node_ids: [...clusterNodes].join(','),
        kind: 'cluster',
        template: cluster.template,
        boundary_mode: 'cluster-import-core',
        center: clusterCenter,
        member_count: members.length,
        movement_count: movements.filter((movement) => clusterNodes.has(String(movement.nodeId))).length,
        connector_count: connectors.filter((feature) => clusterNodes.has(String(feature.properties.node_id))).length,
        surface_area_m2: Math.round(polygonAreaMeters(ring) * 10) / 10,
        rule: 'junction-cluster-template/v2',
      },
      geometry: { type: 'Polygon', coordinates: [[...ring, ring[0]]] },
    });
    diagnostics.push(
      diagnostic(
        'info',
        `junction-cluster:${cluster.id}`,
        [...clusterNodes],
        'junction-cluster-core-applied',
        '已按外部进口截面和簇节点核心生成受限复合路口面。',
        ring[0],
      ),
    );
  }
  return result;
}

function activeComplexCluster(options, clusterId) {
  return Boolean(
    clusterId &&
    (options.junctionTemplates?.enabled ? options.junctionTemplates.clusters || [] : []).some(
      (cluster) => cluster.id === clusterId && cluster.template === 'complex-junction-v1',
    ),
  );
}

function compileJunctionPlans(model, options = {}, diagnostics = []) {
  const byNode = new Map();
  for (const endpoint of model.endpoints) {
    if (!byNode.has(endpoint.nodeId)) byNode.set(endpoint.nodeId, []);
    byNode.get(endpoint.nodeId).push(endpoint);
  }
  const plans = new Map();
  const clusters = options.junctionTemplates?.enabled ? options.junctionTemplates.clusters || [] : [];
  const clusterByNode = new Map(
    clusters.flatMap((cluster) => cluster.nodeIds.map((nodeId) => [String(nodeId), cluster])),
  );
  for (const [nodeId, endpoints] of byNode) {
    const segmentIds = new Set(endpoints.map((endpoint) => endpoint.roadId.replace(/:(forward|backward)$/, '')));
    if (segmentIds.size < 3 || segmentIds.size > 4) continue;
    const approaches = junctionApproaches(model, endpoints);
    if (approaches.length !== segmentIds.size) continue;
    // Rounded curb corners need enough approach length to retain the full
    // turning envelope after the corner is cut toward the junction.
    const baseCutbackMeters = Math.max(...approaches.map((approach) => approach.widthMeters)) * 1.4;
    const node = endpoints[0].coordinate;
    const template = junctionTemplateFor(nodeId, segmentIds, options.junctionTemplates, diagnostics, node);
    const cutbackMeters = baseCutbackMeters * (template?.cutbackMultiplier || 1);
    const boundary = junctionBoundary(
      approaches,
      node,
      cutbackMeters,
      template?.cornerRadiusMultiplier || 1,
      template?.approachWidthMultiplier || 1,
    );
    if (boundary.points.length < 3) continue;
    const cluster = clusterByNode.get(String(nodeId));
    plans.set(nodeId, {
      node,
      segmentIds,
      approaches,
      cutbackMeters,
      boundary: boundary.points,
      boundaryMode: boundary.mode,
      boundaryFallbacks: boundary.fallbacks,
      template: template?.template || null,
      templateReference: template?.referenceFile || null,
      approachWidthMultiplier: template?.approachWidthMultiplier || 1,
      approachLengthMeters: template?.approachLengthMeters || 0,
      clusterId: cluster?.id || null,
    });
  }
  return plans;
}

function junctionApproaches(model, endpoints) {
  const groups = new Map();
  for (const endpoint of endpoints) {
    const road = model.roads.find((item) => item.id === endpoint.roadId);
    if (!road) continue;
    const key = road.segmentId;
    if (!groups.has(key)) groups.set(key, []);
    groups.get(key).push({ endpoint, road });
  }
  return [...groups.values()].map((directions) => {
    const { endpoint, road } = directions[0];
    return {
      segmentId: road.segmentId,
      sourceWayKey: road.osmWayIds.join(','),
      line: endpoint.side === 'end' ? [...road.centerline].reverse() : road.centerline,
      roadIds: directions.map((item) => item.road.id),
      widthMeters: directions.reduce((sum, item) => sum + item.road.widthMeters, 0),
    };
  });
}

// `roadRing` builds the trimmed road's end edge from the direction at the
// cutback point, not at the node. Taking the node-side heading here instead
// leaves the two edges non-parallel whenever the way bends inside the cutback,
// and the junction surface then opens a wedge against the road it should meet.
function headingAtCutback(line, cutbackMeters) {
  const point = pointAlongLine(line, cutbackMeters);
  if (!point) return null;
  let traversed = 0;
  for (let index = 1; index < line.length; index += 1) {
    traversed += distanceMeters(line[index - 1], line[index]);
    // The first original vertex past the cutback is what the trimmed line
    // carries as its second point, so match that pair exactly.
    if (traversed > cutbackMeters + 1e-9) return headingDegrees(point, line[index]);
  }
  return headingAtEndpoint(line);
}

// A dual carriageway reaches a node as two approaches on almost the same
// bearing. Their four side points interleave once sorted by angle, and because
// consecutive points then belong to different segments a rounded corner gets
// inserted between each interleaved pair. Those curves dive back toward the
// node and render as arch-shaped holes in the junction. Merge such approaches
// into one face and keep only its outermost edges.
const PARALLEL_APPROACH_DEGREES = 25;

function signedHeadingDelta(value) {
  return ((((value + 180) % 360) + 360) % 360) - 180;
}

function mergeParallelApproachPoints(points, node) {
  const groups = [];
  for (const item of points) {
    const group = groups.find(
      (candidate) => Math.abs(signedHeadingDelta(candidate.heading - item.outwardHeading)) < PARALLEL_APPROACH_DEGREES,
    );
    if (group) {
      group.points.push(item);
      continue;
    }
    groups.push({ heading: item.outwardHeading, points: [item] });
  }
  return groups.flatMap((group) => {
    const segments = [...new Set(group.points.map((item) => item.segmentId))];
    if (segments.length < 2) return group.points;
    // Order across the face by bearing measured from the group's own heading,
    // so the comparison never straddles the +/-180 discontinuity.
    const sorted = [...group.points].sort(
      (first, second) =>
        signedHeadingDelta(headingDegrees(node, first.point) - group.heading) -
        signedHeadingDelta(headingDegrees(node, second.point) - group.heading),
    );
    const merged = segments.sort().join('+');
    return [sorted[0], sorted.at(-1)].map((item) => ({ ...item, segmentId: merged, sourceWayKey: merged }));
  });
}

function junctionBoundary(approaches, node, cutbackMeters, cornerRadiusMultiplier = 1, approachWidthMultiplier = 1) {
  const points = [];
  for (const approach of approaches) {
    const cutback = pointAlongLine(approach.line, cutbackMeters);
    if (!cutback) continue;
    const heading = headingAtCutback(approach.line, cutbackMeters) ?? headingAtEndpoint(approach.line);
    const half = (approach.widthMeters * approachWidthMultiplier) / 2;
    points.push({
      point: offsetCoordinate(cutback, heading + 90, half),
      segmentId: approach.segmentId,
      sourceWayKey: approach.sourceWayKey,
      outwardHeading: heading,
    });
    points.push({
      point: offsetCoordinate(cutback, heading - 90, half),
      segmentId: approach.segmentId,
      sourceWayKey: approach.sourceWayKey,
      outwardHeading: heading,
    });
  }
  const faces = mergeParallelApproachPoints(points, node);
  const ordered = faces.sort((a, b) => angleAround(node, a.point) - angleAround(node, b.point));
  if (ordered.length < 3) return { points: [], mode: 'approach-envelope' };
  const boundary = [];
  let rounded = 0;
  let fallbacks = 0;
  for (let index = 0; index < ordered.length; index += 1) {
    const first = ordered[index];
    const second = ordered[(index + 1) % ordered.length];
    boundary.push(first.point);
    // One physical OSM way is often split at an intersection node. Its two
    // opposite approaches share a continuous road edge; rounding that edge
    // bends the far side of a T junction and exposes junction asphalt beyond
    // the pedestrian strip.
    if (first.segmentId === second.segmentId || isStraightJunctionEdge(first, second)) continue;
    const curve = roundedCorner(
      node,
      first.point,
      second.point,
      first.outwardHeading,
      second.outwardHeading,
      cornerRadiusMultiplier,
    );
    if (!curve) {
      fallbacks += 1;
      continue;
    }
    boundary.push(...curve.slice(1, -1));
    rounded += 1;
  }
  return { points: boundary, mode: rounded ? 'rounded-approach-envelope' : 'approach-envelope', fallbacks };
}

function templateApproachRing(approach, plan) {
  const innerDistance = plan.cutbackMeters;
  const availableLength = lineLengthMeters(approach.line) - innerDistance - 0.5;
  const lengthMeters = Math.min(plan.approachLengthMeters, availableLength);
  if (lengthMeters < 10) return null;
  const outerDistance = innerDistance + lengthMeters;
  const inner = pointAlongLine(approach.line, innerDistance);
  const outer = pointAlongLine(approach.line, outerDistance);
  const heading = headingAtEndpoint(approach.line);
  const innerHalf = (approach.widthMeters * plan.approachWidthMultiplier) / 2;
  const outerHalf = approach.widthMeters / 2;
  const ring = [
    offsetCoordinate(outer, heading + 90, outerHalf),
    offsetCoordinate(inner, heading + 90, innerHalf),
    offsetCoordinate(inner, heading - 90, innerHalf),
    offsetCoordinate(outer, heading - 90, outerHalf),
    offsetCoordinate(outer, heading + 90, outerHalf),
  ];
  return ring.every((point) => point.every(Number.isFinite)) ? { ring, lengthMeters } : null;
}

function roundedHull(hull, factor) {
  const result = [];
  for (let index = 0; index < hull.length; index += 1) {
    const previous = hull[(index - 1 + hull.length) % hull.length];
    const current = hull[index];
    const next = hull[(index + 1) % hull.length];
    const entry = interpolate(previous, current, factor);
    const exit = interpolate(current, next, factor);
    result.push(entry);
    const curve = quadraticCurve(entry, current, exit, 4);
    result.push(...curve.slice(1, -1));
    result.push(exit);
  }
  return result;
}

function isStraightJunctionEdge(first, second) {
  if (first.sourceWayKey !== second.sourceWayKey) return false;
  const radians = ((first.outwardHeading - second.outwardHeading) * Math.PI) / 180;
  return Math.cos(radians) <= -0.98;
}

function roundedCorner(node, first, second, firstHeading, secondHeading, radiusMultiplier = 1) {
  const origin = node;
  const a = project(first, origin);
  const b = project(second, origin);
  const chord = Math.hypot(a[0] - b[0], a[1] - b[1]);
  if (chord < 0.5 || !Number.isFinite(firstHeading) || !Number.isFinite(secondHeading)) return null;
  const firstDirection = headingVector(firstHeading);
  const secondDirection = headingVector(secondHeading);
  const intersection = lineIntersection(a, firstDirection, b, secondDirection);
  if (!intersection) return null;
  const controlDistance = Math.hypot(...intersection);
  const endpointDistance = Math.max(Math.hypot(...a), Math.hypot(...b));
  // Adjacent approach edge tangents should meet in the corner between the
  // node and the cutback. Reject near-parallel or remote intersections rather
  // than publishing a huge/self-crossing curve.
  if (controlDistance < 0.01 || controlDistance > endpointDistance * 1.5 || controlDistance > 80) return null;
  const scaledIntersection = [intersection[0] * radiusMultiplier, intersection[1] * radiusMultiplier];
  const control = unproject(scaledIntersection, origin);
  return quadraticCurve(first, control, second, JUNCTION_CURVE_SEGMENTS);
}

function junctionTemplateFor(nodeId, segmentIds, configured, diagnostics, node) {
  if (!configured?.enabled) return null;
  const entry = (configured.references || []).find((item) => String(item.nodeId) === String(nodeId));
  if (!entry) return null;
  if (segmentIds.size !== 4) {
    diagnostics.push(
      diagnostic(
        'info',
        `junction:node/${nodeId}`,
        [nodeId],
        'junction-template-topology-skip',
        'cross 模板只应用于四臂路口，当前路口保留 native 几何。',
        node,
      ),
    );
    return null;
  }
  if (entry.template !== 'cross-v1') {
    diagnostics.push(
      diagnostic(
        'warning',
        `junction:node/${nodeId}`,
        [nodeId],
        'junction-template-unsupported',
        '路口模板名称不受支持，已回退 native 几何。',
        node,
      ),
    );
    return null;
  }
  const multiplier = Number(entry.cornerRadiusMultiplier ?? 1);
  if (!Number.isFinite(multiplier) || multiplier < 0.75 || multiplier > 1.25) {
    diagnostics.push(
      diagnostic(
        'warning',
        `junction:node/${nodeId}`,
        [nodeId],
        'junction-template-invalid-parameter',
        'cross 模板圆角参数必须在 0.75 到 1.25 之间，已回退 native 几何。',
        node,
      ),
    );
    return null;
  }
  const cutbackMultiplier = Number(entry.cutbackMultiplier ?? 1);
  if (!Number.isFinite(cutbackMultiplier) || cutbackMultiplier < 1 || cutbackMultiplier > 1.35) {
    diagnostics.push(
      diagnostic(
        'warning',
        `junction:node/${nodeId}`,
        [nodeId],
        'junction-template-invalid-parameter',
        'cross 模板进口过渡参数必须在 1 到 1.35 之间，已回退 native 几何。',
        node,
      ),
    );
    return null;
  }
  const approachWidthMultiplier = Number(entry.approachWidthMultiplier ?? 1);
  if (!Number.isFinite(approachWidthMultiplier) || approachWidthMultiplier < 1 || approachWidthMultiplier > 1.8) {
    diagnostics.push(
      diagnostic(
        'warning',
        `junction:node/${nodeId}`,
        [nodeId],
        'junction-template-invalid-parameter',
        'cross 模板进口宽度参数必须在 1 到 1.8 之间，已回退 native 几何。',
        node,
      ),
    );
    return null;
  }
  const approachLengthMeters = Number(entry.approachLengthMeters ?? 24);
  if (!Number.isFinite(approachLengthMeters) || approachLengthMeters < 10 || approachLengthMeters > 50) {
    diagnostics.push(
      diagnostic(
        'warning',
        `junction:node/${nodeId}`,
        [nodeId],
        'junction-template-invalid-parameter',
        'cross 模板进口过渡长度必须在 10 到 50 米之间，已回退 native 几何。',
        node,
      ),
    );
    return null;
  }
  if (entry.referenceFile && !fs.existsSync(entry.referenceFile)) {
    diagnostics.push(
      diagnostic(
        'warning',
        `junction:node/${nodeId}`,
        [nodeId],
        'junction-template-reference-missing',
        '路口参考文件不存在，已回退 native 几何。',
        node,
      ),
    );
    return null;
  }
  diagnostics.push(
    diagnostic(
      'info',
      `junction:node/${nodeId}`,
      [nodeId],
      'junction-template-applied',
      '已按 cross-v1 模板规整路口面；道路、车道、连接器和控制设施保持 native 结果。',
      node,
    ),
  );
  return {
    template: entry.template,
    referenceFile: entry.referenceFile || null,
    cornerRadiusMultiplier: multiplier,
    cutbackMultiplier,
    approachWidthMultiplier,
    approachLengthMeters,
  };
}

function headingVector(degrees) {
  const radians = (degrees * Math.PI) / 180;
  return [Math.sin(radians), Math.cos(radians)];
}

function lineIntersection(firstPoint, firstDirection, secondPoint, secondDirection) {
  const cross = firstDirection[0] * secondDirection[1] - firstDirection[1] * secondDirection[0];
  if (Math.abs(cross) < 1e-4) return null;
  const delta = [secondPoint[0] - firstPoint[0], secondPoint[1] - firstPoint[1]];
  const firstDistance = (delta[0] * secondDirection[1] - delta[1] * secondDirection[0]) / cross;
  return [firstPoint[0] + firstDirection[0] * firstDistance, firstPoint[1] + firstDirection[1] * firstDistance];
}

function pointAlongLine(line, meters) {
  let remaining = meters;
  for (let index = 1; index < line.length; index += 1) {
    const length = distanceMeters(line[index - 1], line[index]);
    if (length >= remaining) return interpolate(line[index - 1], line[index], remaining / length);
    remaining -= length;
  }
  return line.at(-1);
}

function pointAndAxisAlongLine(line, meters) {
  let remaining = meters;
  for (let index = 1; index < line.length; index += 1) {
    const start = line[index - 1];
    const end = line[index];
    const length = distanceMeters(start, end);
    if (length < 0.01) continue;
    if (length >= remaining) {
      const vector = project(end, start);
      return { point: interpolate(start, end, remaining / length), axis: [vector[0] / length, vector[1] / length] };
    }
    remaining -= length;
  }
  return null;
}

function trimLineAtJunctions(line, sourceNodeIds, junctionPlans) {
  const startCutback = junctionPlans.get(sourceNodeIds[0])?.cutbackMeters || 0;
  const endCutback = junctionPlans.get(sourceNodeIds.at(-1))?.cutbackMeters || 0;
  if (!startCutback && !endCutback) return line;
  const total = lineLengthMeters(line);
  // Short OSM fragments cannot safely lose both ends. Keep their source
  // geometry intact and let the junction diagnostic surface the ambiguity.
  if (startCutback + endCutback >= total - 0.5) return line;
  const result = [];
  let traversed = 0;
  const start = pointAlongLine(line, startCutback);
  const end = pointAlongLine(line, total - endCutback);
  result.push(start);
  for (let index = 1; index < line.length - 1; index += 1) {
    traversed += distanceMeters(line[index - 1], line[index]);
    if (traversed > startCutback && traversed < total - endCutback) result.push(line[index]);
  }
  result.push(end);
  return result;
}

function trimLineAtComplexCluster(line, sourceNodeIds, junctionPlans, cluster, center) {
  if (!center || line.length < 2) return trimLineAtJunctions(line, sourceNodeIds, junctionPlans);
  const boundaryRadius = complexJunctionMetrics(cluster).approachOuterRadius;
  const startInCluster = cluster.nodeIds.map(String).includes(String(sourceNodeIds[0]));
  const endInCluster = cluster.nodeIds.map(String).includes(String(sourceNodeIds.at(-1)));
  const available = lineLengthMeters(line);
  const startDistance = startInCluster ? distanceAlongLineToRadius(line, center, boundaryRadius) : 0;
  const endDistance = endInCluster ? distanceAlongLineToRadius([...line].reverse(), center, boundaryRadius) : 0;
  const startCutback = startDistance > 0 && available > startDistance + 1 ? startDistance : 0;
  const endCutback = endDistance > 0 && available > endDistance + 1 ? endDistance : 0;
  if (!startCutback && !endCutback) return line;
  return trimLineRange(line, startCutback, endCutback);
}

function distanceAlongLineToRadius(line, center, radius) {
  if (!center || line.length < 2) return 0;
  const heading = headingAtEndpoint(line);
  const vector = project(line[0], center);
  const radians = (heading * Math.PI) / 180;
  const startRadius = vector[0] * Math.sin(radians) + vector[1] * Math.cos(radians);
  return Math.max(0, radius - startRadius);
}

function trimLineRange(line, startCutback, endCutback) {
  const total = lineLengthMeters(line);
  if (startCutback + endCutback >= total - 0.5) return line;
  const result = [pointAlongLine(line, startCutback)];
  let traversed = 0;
  for (let index = 1; index < line.length - 1; index += 1) {
    traversed += distanceMeters(line[index - 1], line[index]);
    if (traversed > startCutback && traversed < total - endCutback) result.push(line[index]);
  }
  result.push(pointAlongLine(line, total - endCutback));
  return result;
}

function headingAtEndpoint(line) {
  return headingDegrees(line[0], line[1]);
}
function headingDegrees(a, b) {
  return (Math.atan2((b[0] - a[0]) * Math.cos((a[1] * Math.PI) / 180), b[1] - a[1]) * 180) / Math.PI;
}
function offsetCoordinate(point, degrees, meters) {
  const radians = (degrees * Math.PI) / 180;
  return [
    point[0] + (Math.sin(radians) * meters) / (111320 * Math.cos((point[1] * Math.PI) / 180)),
    point[1] + (Math.cos(radians) * meters) / 111320,
  ];
}
function angleAround(center, point) {
  return Math.atan2(point[1] - center[1], point[0] - center[0]);
}
function sortAround(center, points) {
  return points.sort(
    (a, b) => Math.atan2(a[1] - center[1], a[0] - center[0]) - Math.atan2(b[1] - center[1], b[0] - center[0]),
  );
}
function convexHull(points) {
  const unique = [...new Map(points.map((point) => [`${point[0]},${point[1]}`, point])).values()].sort(
    (a, b) => a[0] - b[0] || a[1] - b[1],
  );
  if (unique.length < 3) return unique;
  const cross = (a, b, c) => (b[0] - a[0]) * (c[1] - a[1]) - (b[1] - a[1]) * (c[0] - a[0]);
  const lower = [];
  for (const point of unique) {
    while (lower.length >= 2 && cross(lower.at(-2), lower.at(-1), point) <= 0) lower.pop();
    lower.push(point);
  }
  const upper = [];
  for (const point of [...unique].reverse()) {
    while (upper.length >= 2 && cross(upper.at(-2), upper.at(-1), point) <= 0) upper.pop();
    upper.push(point);
  }
  return [...lower.slice(0, -1), ...upper.slice(0, -1)];
}
function interpolate(a, b, ratio) {
  return [a[0] + (b[0] - a[0]) * ratio, a[1] + (b[1] - a[1]) * ratio];
}
function distanceMeters(a, b) {
  const dx = (b[0] - a[0]) * 111320 * Math.cos((a[1] * Math.PI) / 180);
  const dy = (b[1] - a[1]) * 111320;
  return Math.hypot(dx, dy);
}
function hasSelfIntersection(ring) {
  for (let first = 0; first < ring.length - 1; first += 1)
    for (let second = first + 1; second < ring.length - 1; second += 1) {
      if (Math.abs(first - second) <= 1 || (first === 0 && second === ring.length - 2)) continue;
      if (segmentsIntersect(ring[first], ring[first + 1], ring[second], ring[second + 1])) return true;
    }
  return false;
}
function segmentsIntersect(a, b, c, d) {
  const cross = (p, q, r) => (q[0] - p[0]) * (r[1] - p[1]) - (q[1] - p[1]) * (r[0] - p[0]);
  const abC = cross(a, b, c);
  const abD = cross(a, b, d);
  const cdA = cross(c, d, a);
  const cdB = cross(c, d, b);
  return ((abC > 0 && abD < 0) || (abC < 0 && abD > 0)) && ((cdA > 0 && cdB < 0) || (cdA < 0 && cdB > 0));
}

function circleRing(center, radius, segments) {
  const origin = center;
  const ring = [];
  for (let index = 0; index <= segments; index += 1) {
    const angle = (index / segments) * Math.PI * 2;
    ring.push(unproject([Math.cos(angle) * radius, Math.sin(angle) * radius], origin));
  }
  return ring;
}

// Offsetting every vertex by a fixed distance along its averaged normal has no
// miter limit: where the centerline turns and the neighbouring segment is short
// — typically the stub left after junction trimming — consecutive offset points
// swap order and the edge doubles back. The ring then self-intersects and the
// folded lobe renders as a hole. Drop the reversed vertices so each offset
// edge keeps travelling the same way as the centerline segment it follows.
function removeOffsetFolds(offset, centerline) {
  let kept = offset.map((point, index) => ({ point, index }));
  for (let guard = 0; guard < offset.length && kept.length > 2; guard += 1) {
    let removed = false;
    for (let position = 0; position < kept.length - 1; position += 1) {
      const from = kept[position];
      const to = kept[position + 1];
      const alongCenter = [
        centerline[to.index][0] - centerline[from.index][0],
        centerline[to.index][1] - centerline[from.index][1],
      ];
      const alongOffset = [to.point[0] - from.point[0], to.point[1] - from.point[1]];
      if (alongCenter[0] * alongOffset[0] + alongCenter[1] * alongOffset[1] >= 0) continue;
      // Keep both termini: they are where the surface meets its junctions.
      kept.splice(position + 1 === kept.length - 1 ? position : position + 1, 1);
      removed = true;
      break;
    }
    if (!removed) break;
  }
  return kept.map((item) => item.point);
}

function roadRing(line, width) {
  if (line.length < 2 || !Number.isFinite(width)) return null;
  const origin = line[0];
  const points = line.map((point) => project(point, origin));
  const left = [];
  const right = [];
  const half = width / 2;
  for (let i = 0; i < points.length; i += 1) {
    const prior = points[Math.max(0, i - 1)];
    const next = points[Math.min(points.length - 1, i + 1)];
    const dx = next[0] - prior[0];
    const dy = next[1] - prior[1];
    const length = Math.hypot(dx, dy);
    if (length < 0.01) return null;
    const nx = (-dy / length) * half;
    const ny = (dx / length) * half;
    left.push([points[i][0] + nx, points[i][1] + ny]);
    right.push([points[i][0] - nx, points[i][1] - ny]);
  }
  const leftEdge = removeOffsetFolds(left, points).map((point) => unproject(point, origin));
  const rightEdge = removeOffsetFolds(right, points).map((point) => unproject(point, origin));
  if (leftEdge.length < 2 || rightEdge.length < 2) return null;
  const ring = [...leftEdge, ...rightEdge.reverse(), leftEdge[0]];
  return ring.every((point) => point.every(Number.isFinite)) ? ring : null;
}

function sidewalkRing(line, innerOffset, outerOffset, side) {
  const inner = offsetLine(line, innerOffset * side);
  const outer = offsetLine(line, outerOffset * side);
  if (!inner || !outer) return null;
  const ring = [...inner, ...outer.reverse(), inner[0]];
  return ring.every((point) => point.every(Number.isFinite)) ? ring : null;
}

function project(point, origin) {
  const scale = 111320;
  return [(point[0] - origin[0]) * scale * Math.cos((origin[1] * Math.PI) / 180), (point[1] - origin[1]) * scale];
}
function unproject(point, origin) {
  const scale = 111320;
  return [point[0] / (scale * Math.cos((origin[1] * Math.PI) / 180)) + origin[0], point[1] / scale + origin[1]];
}
function diagnostic(severity, subjectId, sourceIds, rule, message, coordinate) {
  return {
    id: `diagnostic:${rule}:${subjectId}`,
    severity,
    subjectId,
    sourceIds,
    rule,
    message,
    geometry: coordinate ? { type: 'Point', coordinates: coordinate } : null,
  };
}
function xmlAttrs(text) {
  const attrs = {};
  for (const match of text.matchAll(/([:\w-]+)\s*=\s*(?:"([^"]*)"|'([^']*)')/g)) attrs[match[1]] = match[2] ?? match[3];
  return attrs;
}
function parseTags(body) {
  const tags = {};
  for (const match of body.matchAll(/<tag\b([^>]*)\/?\s*>/g)) {
    const attrs = xmlAttrs(match[1]);
    if (attrs.k) tags[attrs.k] = attrs.v || '';
  }
  return tags;
}
function positiveInteger(value) {
  const number = Number(value);
  return Number.isInteger(number) && number > 0 ? number : null;
}
function positiveNumber(value) {
  const match = String(value ?? '').match(/^\s*(\d+(?:\.\d+)?)/);
  const number = match ? Number(match[1]) : null;
  return Number.isFinite(number) && number > 0 ? number : null;
}
function writeJsonAtomic(file, data) {
  fs.mkdirSync(path.dirname(file), { recursive: true });
  const temporary = `${file}.${process.pid}.tmp`;
  fs.writeFileSync(temporary, `${JSON.stringify(data, null, 2)}\n`);
  fs.renameSync(temporary, file);
}

module.exports = {
  OVERRIDE_SCHEMA,
  compileRoadModel,
  compileGeometry,
  loadOverrides,
  validateOverrides,
  writeJsonAtomic,
};