#!/usr/bin/env node
"use strict";

const fs = require("fs");
const http = require("http");
const path = require("path");
const { loadOverrides, validateOverrides, writeJsonAtomic } = require("../src/compile/native-road");
const { generate, validateDocument, runtime } = require("../src/native-traffic-signals");
const { convertGeoJson } = require("../src/reference/gaode");
const { exportNativeRoadPackage } = require("../src/export/native-road-package");

function startWorkbench({ area, configPath, repoRoot, compileFresh, readAreaConfig, junctionReference = null, debug = false, port = 8787 }) {
  if (typeof junctionReference === "string") junctionReference = readJunctionReference(junctionReference);
  // `--debug` surfaces advisory compiler findings that have no geometry layer of
  // their own — currently the complex-junction candidates. Off by default so the
  // normal editing view stays uncluttered.
  if (!Number.isInteger(port) || port < 1024 || port > 65535) throw new Error("--port must be an integer in [1024, 65535].");
  const context = { repoRoot, configPath, compileFresh, readAreaConfig };
  const server = http.createServer((request, response) => handle(request, response, area, context, junctionReference, debug));
  server.on("error", (error) => {
    console.error(`Road Workbench failed to listen: ${error.message}`);
    process.exitCode = 1;
  });
  server.listen(port, "127.0.0.1", () => console.log(`Road Workbench: http://127.0.0.1:${port}/${debug ? "  (debug: 复杂路口候选已开启)" : ""}`));
  return server;
}

function handle(request, response, area, context, junctionReference, debug = false) {
  const url = new URL(request.url, "http://127.0.0.1");
  if (request.method === "GET" && url.pathname === "/") return sendFile(response, path.join(__dirname, "client", "index.html"), "text/html; charset=utf-8");
  if (request.method === "GET" && url.pathname === "/app.js") return sendFile(response, path.join(__dirname, "client", "app.js"), "text/javascript; charset=utf-8");
  if (request.method === "GET" && url.pathname === "/app.css") return sendFile(response, path.join(__dirname, "client", "app.css"), "text/css; charset=utf-8");
  if (request.method === "GET" && url.pathname.startsWith("/vendor/")) return sendVendorFile(response, url.pathname, context.repoRoot);
  if (request.method === "GET" && url.pathname === "/api/state") return sendJson(response, 200, state(area, junctionReference, debug));
  if (request.method === "GET" && url.pathname === "/api/export.zip") return Promise.resolve().then(() => {
    const exported = exportNativeRoadPackage(area.outputs.nativeRoadDir);
    response.writeHead(200, {
      "Content-Type": "application/zip",
      "Content-Disposition": `attachment; filename="${area.id}.native-road.zip"`,
      "Content-Length": exported.bytes.length,
      "Cache-Control": "no-store",
    });
    response.end(Buffer.from(exported.bytes));
  }).catch((error) => sendJson(response, 400, { ok: false, error: error.message }));
  if (request.method === "POST" && url.pathname === "/api/traffic-signals") return readBody(request).then((body) => {
    const document = validateDocument(body, fs.readFileSync(area.input, "utf8"));
    writeJsonAtomic(area.outputs.nativeTrafficSignals, document);
    sendJson(response, 200, { ok: true, trafficSignals: document, runtime: runtime(document) });
  }).catch((error) => sendJson(response, 400, { ok: false, error: error.message }));
  if (request.method === "POST" && url.pathname === "/api/traffic-signals/generate") return Promise.resolve().then(() => {
    const compiled = readCompiled(area);
    const generated = generate(fs.readFileSync(area.input, "utf8"), readLayer(path.join(area.outputs.nativeRoadDir, "layers", "vehicle_stop_lines.geojson")), readLayer(path.join(area.outputs.nativeRoadDir, "layers", "intersection_surface.geojson")));
    const current = validateDocument(readJson(area.outputs.nativeTrafficSignals), fs.readFileSync(area.input, "utf8"));
    const present = new Set(current.assemblies.features.map((feature) => feature.properties.signal_uid));
    current.assemblies.features.push(...generated.assemblies.features.filter((feature) => !present.has(feature.properties.signal_uid)));
    writeJsonAtomic(area.outputs.nativeTrafficSignals, current);
    sendJson(response, 200, { ok: true, trafficSignals: current, runtime: runtime(current), generated: generated.assemblies.features.length, compiled: Boolean(compiled) });
  }).catch((error) => sendJson(response, 400, { ok: false, error: error.message }));
  if (request.method === "POST" && url.pathname === "/api/overrides") return readBody(request).then((body) => {
    const compiled = readCompiled(area);
    const overrides = validateOverrides(body, { roads: compiled.model.roads, endpoints: compiled.model.endpoints });
    writeJsonAtomic(area.outputs.nativeRoadOverrides, overrides);
    sendJson(response, 200, { ok: true, overrides });
  }).catch((error) => sendJson(response, 400, { ok: false, error: error.message }));
  if (request.method === "POST" && url.pathname === "/api/junction-clusters") return readBody(request).then((body) => {
    if (!debug) throw new Error("该接口仅在 --debug 模式下可用。");
    const added = addJunctionCluster(context.configPath, body, readCompiled(area), context.readAreaConfig, context.repoRoot);
    context.compileFresh();
    const refreshed = context.readAreaConfig(context.configPath, { repoRoot: context.repoRoot });
    sendJson(response, 200, { ok: true, added, ...state(refreshed, junctionReference, debug) });
  }).catch((error) => sendJson(response, 400, { ok: false, error: error.message }));
  if (request.method === "POST" && url.pathname === "/api/compile") return Promise.resolve().then(() => {
    context.compileFresh();
    sendJson(response, 200, state(area, junctionReference));
  }).catch((error) => sendJson(response, 500, { ok: false, error: error.message }));
  sendJson(response, 404, { error: "Not found" });
}

function state(area, junctionReference = null, debug = false) {
  const nativeDir = area.outputs.nativeRoadDir;
  const osm2streetsRoadSurface = path.join(area.outputs.geojsonDir, "road_surface.geojson");
  const trafficSignals = fs.existsSync(area.outputs.nativeTrafficSignals)
    ? validateDocument(readJson(area.outputs.nativeTrafficSignals), fs.readFileSync(area.input, "utf8"))
    : { schema: "native-traffic-signals/v1", provenance: "empty", assemblies: { type: "FeatureCollection", features: [] } };
  const trafficRuntime = runtime(trafficSignals);
  const compiled = readCompiled(area);
  return { areaId: area.id, debug: debug ? { junctionCandidates: junctionCandidates(compiled) } : null, compiled, overrides: loadOverrides(area.outputs.nativeRoadOverrides), trafficSignals, trafficRuntime, comparison: readJson(path.join(nativeDir, "comparison.json")), junctionReference, layers: { nativeRoadSurface: readLayer(path.join(nativeDir, "layers", "road_surface.geojson")), edgeLines: readLayer(path.join(nativeDir, "layers", "edge_lines.geojson")), nativeSidewalkSurface: readLayer(path.join(nativeDir, "layers", "sidewalk_surface.geojson")), nativeIntersectionSurface: readLayer(path.join(nativeDir, "layers", "intersection_surface.geojson")), laneCenterlines: readLayer(path.join(nativeDir, "layers", "lane_centerlines.geojson")), laneSeparators: readLayer(path.join(nativeDir, "layers", "lane_separators.geojson")), centerLines: readLayer(path.join(nativeDir, "layers", "center_lines.geojson")), directionArrows: readLayer(path.join(nativeDir, "layers", "direction_arrows.geojson")), turnArrows: readLayer(path.join(nativeDir, "layers", "turn_arrows.geojson")), crosswalks: readLayer(path.join(nativeDir, "layers", "crosswalks.geojson")), vehicleStopLines: readLayer(path.join(nativeDir, "layers", "vehicle_stop_lines.geojson")), connectors: readLayer(path.join(nativeDir, "layers", "connectors.geojson")), osm2streetsRoadSurface: fs.existsSync(osm2streetsRoadSurface) ? readLayer(osm2streetsRoadSurface) : null } };
}
// The compiler reports candidates as advisory diagnostics. Lift them into their
// own payload with a stable index so the map can label them "#1, #2, ..." and
// the inspector can offer a ready-to-paste cluster配置.
// Append one detected cluster to the hand-authored area config. The candidate
// must still be present in the latest compile, so a stale browser tab cannot
// write a cluster that no longer exists. The edited config is validated by the
// real loader before it replaces the file: an invalid write would break every
// later command, and the file is git-tracked so a bad accept stays revertible.
function addJunctionCluster(configPath, body, compiled, readAreaConfig, repoRoot) {
  const index = Number(body?.index);
  if (!Number.isInteger(index)) throw new Error("请求缺少候选编号 index。");
  const candidate = junctionCandidates(compiled).find((item) => item.index === index);
  if (!candidate) throw new Error(`候选 #${index} 不在最新一次编译结果里，请刷新页面后重试。`);
  const raw = readJson(configPath);
  const templates = raw.nativeRoad?.junctionTemplates;
  if (!templates) throw new Error("区域配置缺少 nativeRoad.junctionTemplates，请先手工建立该节点。");
  const clusters = Array.isArray(templates.clusters) ? templates.clusters : [];
  const taken = new Set(clusters.flatMap((cluster) => (cluster.nodeIds || []).map(String)));
  const clash = candidate.nodeIds.filter((nodeId) => taken.has(String(nodeId)));
  if (clash.length) throw new Error(`节点 ${clash.join("、")} 已属于其他复杂路口配置。`);
  const id = uniqueClusterId(`cluster-${candidate.nodeIds[0]}`, new Set(clusters.map((cluster) => cluster.id)));
  const cluster = {
    id,
    template: candidate.template,
    coreRadiusMeters: candidate.coreRadiusMeters,
    cornerRadiusMeters: 12,
    outerRadiusExtraMeters: 18,
    nodeIds: candidate.nodeIds.map(String),
  };
  const next = { ...raw, nativeRoad: { ...raw.nativeRoad, junctionTemplates: { ...templates, enabled: true, clusters: [...clusters, cluster] } } };
  const staging = `${configPath}.candidate-${process.pid}.json`;
  fs.writeFileSync(staging, `${JSON.stringify(next, null, 2)}\n`);
  try {
    readAreaConfig(staging, { repoRoot });
  } catch (error) {
    fs.unlinkSync(staging);
    throw new Error(`写入后的配置无法通过校验，已放弃：${error.message}`);
  }
  fs.unlinkSync(staging);
  writeJsonAtomic(configPath, next);
  return cluster;
}
function uniqueClusterId(base, taken) {
  if (!taken.has(base)) return base;
  for (let suffix = 2; suffix < 100; suffix += 1) if (!taken.has(`${base}-${suffix}`)) return `${base}-${suffix}`;
  throw new Error("无法生成唯一的 cluster id。");
}

function junctionCandidates(compiled) {
  return (compiled?.diagnostics || [])
    .filter((item) => item.rule === "complex-junction-candidate" && item.suggestedCluster)
    .sort((first, second) => second.suggestedCluster.nodeCount - first.suggestedCluster.nodeCount || first.suggestedCluster.diameterMeters - second.suggestedCluster.diameterMeters)
    .map((item, index) => ({ index: index + 1, id: item.id, message: item.message, coordinate: item.geometry?.coordinates || null, ...item.suggestedCluster }));
}

function readJunctionReference(file) {
  if (!fs.existsSync(file)) throw new Error(`Junction reference not found: ${file}`);
  const converted = convertGeoJson(JSON.parse(fs.readFileSync(file, "utf8")));
  return { source: file, coordinateSystem: "GCJ-02", converted };
}
function readCompiled(area) { return readJson(path.join(area.outputs.nativeRoadDir, "compiled.json")); }
function readJson(file) { return JSON.parse(fs.readFileSync(file, "utf8")); }
function readLayer(file) { return fs.existsSync(file) ? readJson(file) : { type: "FeatureCollection", features: [] }; }
function readBody(request) { return new Promise((resolve, reject) => { let body = ""; request.setEncoding("utf8"); request.on("data", (part) => { body += part; if (body.length > 1024 * 1024) request.destroy(); }); request.on("end", () => { try { resolve(JSON.parse(body)); } catch (_) { reject(new Error("Request body must be JSON.")); } }); request.on("error", reject); }); }
function sendFile(response, file, type) { response.writeHead(200, { "Content-Type": type, "Cache-Control": "no-store" }); fs.createReadStream(file).pipe(response); }
function sendVendorFile(response, pathname, repoRoot) {
  const match = /^\/vendor\/(ol|rbush|quickselect)\/(.+)$/.exec(pathname);
  if (!match) return sendJson(response, 404, { error: "Not found" });
  const root = path.join(repoRoot, "node_modules", match[1]);
  const file = path.resolve(root, match[2]);
  if (!file.startsWith(`${root}${path.sep}`) || !fs.existsSync(file) || !fs.statSync(file).isFile()) return sendJson(response, 404, { error: "Not found" });
  return sendFile(response, file, file.endsWith(".css") ? "text/css; charset=utf-8" : "text/javascript; charset=utf-8");
}
function sendJson(response, status, value) { response.writeHead(status, { "Content-Type": "application/json; charset=utf-8", "Cache-Control": "no-store" }); response.end(`${JSON.stringify(value)}\n`); }
module.exports = { startWorkbench };