#!/usr/bin/env node

const fs = require("fs");
const path = require("path");
const { spawnSync } = require("child_process");

const repoRoot = path.resolve(__dirname, "..");
const args = parseArgs(process.argv.slice(2));
const configPath = path.resolve(
  args.config || path.join(repoRoot, "config", "areas", "nantaizi-lake-innovation-valley.json"),
);
const area = normalizeAreaConfig(readJson(configPath));
const requestedStages = args.stages
  ? splitList(args.stages)
  : null;
const stages = resolveStages(area.stages, requestedStages);

console.log(`Area: ${area.id}`);
console.log(`Config: ${configPath}`);
console.log(`Output: ${area.outputs.areaDir}`);

if (stages.intermediates) {
  buildIntermediates(area);
}
if (stages.blender) {
  buildBlenderScene(area);
}
if (stages.cesium) {
  exportCesium(area);
}
if (stages.preview) {
  writeCesiumPreview(area);
}

console.log("Done.");

function parseArgs(argv) {
  const out = {};
  for (let i = 0; i < argv.length; i += 1) {
    const arg = argv[i];
    if (!arg.startsWith("--")) continue;
    const key = arg.slice(2).replace(/-([a-z])/g, (_, c) => c.toUpperCase());
    const next = argv[i + 1];
    if (!next || next.startsWith("--")) {
      out[key] = "true";
    } else {
      out[key] = next;
      i += 1;
    }
  }
  return out;
}

function readJson(file) {
  if (!fs.existsSync(file)) {
    throw new Error(`Config file not found: ${file}`);
  }
  return JSON.parse(fs.readFileSync(file, "utf8"));
}

function normalizeAreaConfig(raw) {
  const id = requireText(raw.id, "id");
  const input = path.resolve(requireText(raw.input, "input"));
  if (!fs.existsSync(input)) {
    throw new Error(`Input OSM XML not found: ${input}`);
  }

  const outputRoot = path.resolve(raw.outputRoot || path.join(repoRoot, "outputs"));
  const outputOverrides = raw.outputs || {};
  const areaDir = path.resolve(outputOverrides.areaDir || path.join(outputRoot, id));
  const fileStem = outputOverrides.fileStem || id;
  const outputs = {
    areaDir,
    geojsonDir: path.resolve(outputOverrides.geojsonDir || path.join(areaDir, "osm2streets_web_out")),
    gpkg: path.resolve(outputOverrides.gpkg || path.join(areaDir, `${fileStem}.gpkg`)),
    qgisProject: path.resolve(outputOverrides.qgisProject || path.join(areaDir, `${fileStem}.qgz`)),
    qgisPreview: path.resolve(outputOverrides.qgisPreview || path.join(areaDir, `${fileStem}-preview.png`)),
    blend: path.resolve(outputOverrides.blend || path.join(areaDir, `${fileStem}.blend`)),
    render: path.resolve(outputOverrides.render || path.join(areaDir, `${fileStem}.png`)),
    glb: path.resolve(outputOverrides.glb || path.join(areaDir, `${fileStem}.glb`)),
    metadata: path.resolve(outputOverrides.metadata || path.join(areaDir, `${fileStem}.json`)),
    cesiumPreview: path.resolve(
      outputOverrides.cesiumPreview || path.join(areaDir, `${fileStem}-cesium-preview.html`),
    ),
    pipelineDir: path.resolve(outputOverrides.pipelineDir || path.join(areaDir, "_pipeline")),
  };

  return {
    id,
    input,
    outputRoot,
    qgisApp: raw.qgisApp || "/Applications/QGIS.app",
    blenderApp: raw.blenderApp || "/Applications/Blender.app",
    stages: {
      intermediates: raw.stages?.intermediates ?? raw.stages?.qgis ?? true,
      blender: raw.stages?.blender ?? true,
      cesium: raw.stages?.cesium ?? true,
      preview: false,
    },
    qgis: {
      arrowScale: raw.qgis?.arrowScale ?? raw.arrowScale ?? 0.8,
      clipPad: raw.qgis?.clipPad ?? raw.clipPad ?? 0.002,
      canvasPad: raw.qgis?.canvasPad ?? raw.canvasPad ?? 0.001,
      previewPad: raw.qgis?.previewPad ?? raw.previewPad ?? 0.0007,
      canvasExtent: raw.qgis?.canvasExtent ?? raw.canvasExtent ?? null,
      previewExtent: raw.qgis?.previewExtent ?? raw.previewExtent ?? null,
      layerPrefix: raw.qgis?.layerPrefix ?? raw.layerPrefix ?? "osm2streets",
    },
    osm2streets: raw.osm2streets || {
      debug_each_step: false,
      dual_carriageway_experiment: false,
      sidepath_zipping_experiment: false,
      inferred_sidewalks: true,
      osm2lanes: true,
    },
    blender: {
      treeStyle: raw.blender?.treeStyle || "natural",
      officeOverrides: raw.blender?.officeOverrides || raw.blender?.office_overrides || "",
    },
    outputs,
  };
}

function requireText(value, key) {
  if (typeof value !== "string" || value.trim() === "") {
    throw new Error(`Missing config key: ${key}`);
  }
  return value;
}

function splitList(value) {
  return String(value)
    .split(",")
    .map((item) => item.trim())
    .filter(Boolean);
}

function resolveStages(defaults, requested) {
  if (!requested) return defaults;
  const aliases = {
    all: ["intermediates", "blender", "cesium"],
    qgis: ["intermediates"],
    osm2streets: ["intermediates"],
    geojson: ["intermediates"],
    intermediate: ["intermediates"],
    intermediates: ["intermediates"],
    blender: ["blender"],
    scene: ["blender"],
    cesium: ["cesium"],
    glb: ["cesium"],
    preview: ["preview"],
    html: ["preview"],
    cesiumPreview: ["preview"],
  };
  const out = { intermediates: false, blender: false, cesium: false, preview: false };
  for (const stage of requested) {
    const mapped = aliases[stage];
    if (!mapped) {
      throw new Error(`Unknown stage '${stage}'. Use intermediates, blender, cesium, preview, or all.`);
    }
    for (const key of mapped) out[key] = true;
  }
  return out;
}

function buildIntermediates(area) {
  fs.mkdirSync(area.outputs.pipelineDir, { recursive: true });
  const derivedConfig = {
    qgisApp: area.qgisApp,
    input: area.input,
    outDir: area.outputs.geojsonDir,
    gpkg: area.outputs.gpkg,
    project: area.outputs.qgisProject,
    preview: area.outputs.qgisPreview,
    arrowScale: area.qgis.arrowScale,
    clipPad: area.qgis.clipPad,
    canvasPad: area.qgis.canvasPad,
    previewPad: area.qgis.previewPad,
    canvasExtent: area.qgis.canvasExtent,
    previewExtent: area.qgis.previewExtent,
    layerPrefix: area.qgis.layerPrefix,
    osm2streets: area.osm2streets,
  };
  const derivedConfigPath = path.join(area.outputs.pipelineDir, "osm2streets-qgis.config.json");
  fs.writeFileSync(derivedConfigPath, `${JSON.stringify(derivedConfig, null, 2)}\n`);

  console.log("Stage: intermediates (osm2streets GeoJSON + QGIS)");
  runCommand(process.execPath, [
    path.join(repoRoot, "scripts", "build-osm2streets-qgis.js"),
    "--config",
    derivedConfigPath,
  ], "intermediates");
}

function buildBlenderScene(area) {
  ensureFile(blenderExecutable(area), "Blender executable");
  ensureFile(path.join(repoRoot, "blender", "generate_scene.py"), "Blender scene generator");
  fs.mkdirSync(path.dirname(area.outputs.blend), { recursive: true });
  fs.mkdirSync(path.dirname(area.outputs.render), { recursive: true });

  const blenderArgs = [
    "--background",
    "--factory-startup",
    "--python",
    path.join(repoRoot, "blender", "generate_scene.py"),
    "--",
    "--osm",
    area.input,
    "--geojson",
    area.outputs.geojsonDir,
    "--output",
    area.outputs.blend,
    "--render",
    area.outputs.render,
    "--tree-style",
    area.blender.treeStyle,
  ];
  if (area.blender.officeOverrides) {
    blenderArgs.push("--office-overrides", area.blender.officeOverrides);
  }

  console.log("Stage: blender");
  runCommand(blenderExecutable(area), blenderArgs, "blender");
}

function exportCesium(area) {
  ensureFile(blenderExecutable(area), "Blender executable");
  ensureFile(area.outputs.blend, "Blend scene");
  ensureFile(path.join(repoRoot, "blender", "export_cesium.py"), "Cesium exporter");
  fs.mkdirSync(path.dirname(area.outputs.glb), { recursive: true });
  fs.mkdirSync(path.dirname(area.outputs.metadata), { recursive: true });

  console.log("Stage: cesium");
  runCommand(blenderExecutable(area), [
    "--background",
    "--python",
    path.join(repoRoot, "blender", "export_cesium.py"),
    "--",
    "--blend",
    area.outputs.blend,
    "--glb",
    area.outputs.glb,
    "--metadata",
    area.outputs.metadata,
  ], "cesium");
  writeCesiumPreview(area);
}

function blenderExecutable(area) {
  return path.join(area.blenderApp, "Contents", "MacOS", "Blender");
}

function ensureFile(file, label) {
  if (!fs.existsSync(file)) {
    throw new Error(`${label} not found: ${file}`);
  }
}

function runCommand(command, commandArgs, stage) {
  const result = spawnSync(command, commandArgs, { stdio: "inherit" });
  if (result.error) {
    throw result.error;
  }
  if (result.status !== 0) {
    const signal = result.signal ? ` signal=${result.signal}` : "";
    throw new Error(`Stage '${stage}' failed with status=${result.status}${signal}`);
  }
}

function writeCesiumPreview(area) {
  ensureFile(area.outputs.glb, "Cesium GLB");
  ensureFile(area.outputs.metadata, "Cesium metadata");
  const htmlPath = area.outputs.cesiumPreview;
  fs.mkdirSync(path.dirname(htmlPath), { recursive: true });
  const glbName = path.basename(area.outputs.glb);
  const metadataName = path.basename(area.outputs.metadata);
  fs.writeFileSync(htmlPath, cesiumPreviewHtml(glbName, metadataName, area.id));
  console.log(`Cesium preview: ${htmlPath}`);
}

function cesiumPreviewHtml(glbName, metadataName, areaId) {
  return `<!doctype html>
<html lang="zh-CN">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>${escapeHtml(areaId)} Cesium Preview</title>
  <script src="https://cdn.jsdelivr.net/npm/cesium@1.121.1/Build/Cesium/Cesium.js"></script>
  <link href="https://cdn.jsdelivr.net/npm/cesium@1.121.1/Build/Cesium/Widgets/widgets.css" rel="stylesheet">
  <style>
    html, body, #cesiumContainer {
      width: 100%;
      height: 100%;
      margin: 0;
      overflow: hidden;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    }
    #status {
      position: absolute;
      left: 12px;
      bottom: 12px;
      z-index: 1;
      max-width: 520px;
      padding: 8px 10px;
      border-radius: 4px;
      background: rgba(20, 24, 28, 0.78);
      color: #fff;
      font-size: 12px;
      line-height: 1.45;
    }
  </style>
</head>
<body>
  <div id="cesiumContainer"></div>
  <div id="status">Loading ${escapeHtml(glbName)}...</div>
  <script>
    const statusEl = document.getElementById("status");
    Cesium.Ion.defaultAccessToken = "";

    async function main() {
      const metadata = await fetch("${escapeJs(metadataName)}").then((r) => r.json());
      const anchor = metadata.anchor || {};
      const longitude = Number(anchor.longitude || 0);
      const latitude = Number(anchor.latitude || 0);
      const height = Number(anchor.height || 0);
      const heading = Number(metadata.heading_correction_degrees || 0);

      const viewer = new Cesium.Viewer("cesiumContainer", {
        animation: false,
        timeline: false,
        baseLayerPicker: false,
        geocoder: false,
        navigationHelpButton: false,
        sceneModePicker: false,
        homeButton: true,
        fullscreenButton: true,
        infoBox: false,
        selectionIndicator: false,
        baseLayer: false
      });
      viewer.scene.globe.depthTestAgainstTerrain = true;

      const p = Cesium.Cartesian3.fromDegrees(longitude, latitude, height);
      const enu = Cesium.Transforms.eastNorthUpToFixedFrame(p);
      const correction = Cesium.Matrix3.fromRotationZ(Cesium.Math.toRadians(heading));
      const modelMatrix = Cesium.Matrix4.multiplyByMatrix3(enu, correction, new Cesium.Matrix4());
      const model = await Cesium.Model.fromGltfAsync({
        url: "${escapeJs(glbName)}",
        modelMatrix,
        scale: 1.0
      });
      viewer.scene.primitives.add(model);

      const center = Cesium.Cartesian3.fromDegrees(longitude, latitude, height);
      viewer.camera.flyToBoundingSphere(
        new Cesium.BoundingSphere(center, 900.0),
        { duration: 0.0 }
      );
      statusEl.textContent = "${escapeJs(glbName)} | " + longitude.toFixed(6) + ", " + latitude.toFixed(6);
    }

    main().catch((error) => {
      console.error(error);
      statusEl.textContent = "Failed to load Cesium preview: " + error.message;
    });
  </script>
</body>
</html>
`;
}

function escapeHtml(value) {
  return String(value)
    .replaceAll("&", "&amp;")
    .replaceAll("<", "&lt;")
    .replaceAll(">", "&gt;")
    .replaceAll('"', "&quot;");
}

function escapeJs(value) {
  return String(value).replaceAll("\\", "\\\\").replaceAll('"', '\\"');
}