// Synthetic road for the probe, so the page runs without importing OSM or
// touching the workbench API. Geometry helpers come from the real edit modules
// on purpose: the probe has to exercise the production conversion, not a copy.

import { offsetCoordinate, polylineLengthMeters, type Coordinate } from '../../src/edit/meters';
import type { EditHandle } from '../../src/edit/types';

/** The road heads due north, so its normal — the drag axis — points due east. */
export const TANGENT_AZIMUTH = 0;
export const AXIS_AZIMUTH = 90;
export const WIDTH_METERS = 12;
export const LANE_COUNT = 4;

export const CENTERLINE: Coordinate[] = [
  [116.397, 39.905],
  [116.397, 39.915],
];

export const ROAD_LENGTH_METERS = polylineLengthMeters(CENTERLINE);

const MIDPOINT: Coordinate = [116.397, 39.91];

/** Outer ring of the baseline road surface, EPSG:4326. */
export function roadSurfaceRing(): Coordinate[] {
  const half = WIDTH_METERS / 2;
  const left = CENTERLINE.map((point) => offsetCoordinate(point, TANGENT_AZIMUTH + 90, half));
  const right = CENTERLINE.map((point) => offsetCoordinate(point, TANGENT_AZIMUTH - 90, half));
  return [...left, ...right.reverse(), left[0]];
}

/** Lane divider lines, to make it obvious if the baseline ever gets rewritten. */
export function laneDividerLines(): Coordinate[][] {
  const laneWidth = WIDTH_METERS / LANE_COUNT;
  const lines: Coordinate[][] = [];
  for (let index = 1; index < LANE_COUNT; index += 1) {
    const lateral = -WIDTH_METERS / 2 + laneWidth * index;
    lines.push(CENTERLINE.map((point) => offsetCoordinate(point, TANGENT_AZIMUTH + 90, lateral)));
  }
  return lines;
}

/**
 * A left edge-offset handle shaped exactly like the one `makeRoadHandles()`
 * emits, so `projectHandleValue()` sees production input.
 */
export const PROBE_HANDLE: EditHandle = {
  handleId: 'probe:road-edge-offset:left',
  kind: 'road-edge-offset',
  anchor: {
    type: 'road-interval',
    roadId: 'probe:road/1:forward',
    startStation: 0.15,
    endStation: 0.85,
    side: 'left',
  },
  position: offsetCoordinate(MIDPOINT, AXIS_AZIMUTH, WIDTH_METERS / 2),
  axisAzimuth: AXIS_AZIMUTH,
  value: { current: 0, min: -WIDTH_METERS * 0.45, max: WIDTH_METERS * 0.45, unit: 'meter' },
  affects: [],
  editable: true,
};