#!/usr/bin/env node
import { createHash } from 'node:crypto';
import { brotliCompressSync, constants as zlibConstants } from 'node:zlib';
import { readFile, readdir, stat } from 'node:fs/promises';
import { relative, resolve, sep } from 'node:path';
import sharp from 'sharp';
import { fileTypeFromBuffer } from 'file-type';
import { probeVideo, runMediaCommand } from './lib/video-frames.mjs';
import {
  classifyArtifact,
  evaluateBudgetTotals,
  evaluateMediaAssetBudget,
  normalizeDetectedMediaType,
  resolveBudgetGateMode,
  validateRuntimeBudgetTraceReport,
} from './lib/bundle-budgets.mjs';

const root = resolve(process.argv[2] ?? 'dist');
const transferOnly = process.argv.includes('--transfer-only');
const runtimeTraceIndex = process.argv.indexOf('--runtime-trace');
const runtimeTracePath = runtimeTraceIndex === -1 ? null : process.argv[runtimeTraceIndex + 1];
if (runtimeTraceIndex !== -1 && runtimeTracePath === undefined) throw new Error('--runtime-trace requires one explicit drive-trace JSON path.');
const gateMode = resolveBudgetGateMode({ transferOnly, runtimeTracePath });
if (!(await stat(root)).isDirectory()) throw new Error('Bundle budget target must be a directory.');

const listFiles = async (directory) => {
  const files = [];
  for (const entry of await readdir(directory, { withFileTypes: true })) {
    const path = resolve(directory, entry.name);
    if (entry.isSymbolicLink()) throw new Error('Bundle budget input cannot contain symbolic links.');
    if (entry.isDirectory()) files.push(...await listFiles(path));
    else if (entry.isFile()) files.push(path);
    else throw new Error('Bundle budget input contains an unsupported entry.');
  }
  return files;
};

const compressedSize = (path, bytes) => (/\.(?:avif|br|gif|jpe?g|mp3|mp4|opus|png|webm|webp|woff2?)$/iu.test(path)
  ? bytes.byteLength
  : brotliCompressSync(bytes, { params: { [zlibConstants.BROTLI_PARAM_QUALITY]: 11 } }).byteLength);

const readJson = async (path, label) => {
  try { return JSON.parse(await readFile(path, 'utf8')); } catch { throw new Error(`${label} must be valid JSON.`); }
};

const probeAudio = async (path) => {
  const { stdout } = await runMediaCommand('ffprobe', [
    '-v', 'error', '-show_entries', 'format=duration:stream=codec_type', '-of', 'json', path,
  ], 'ASSET-AUDIO-PROBE-001', 20_000);
  let result;
  try { result = JSON.parse(stdout); } catch { throw new Error('ASSET-AUDIO-PROBE-001'); }
  const streams = Array.isArray(result.streams) ? result.streams : [];
  const duration = Number(result.format?.duration);
  if (streams.length !== 1 || streams[0]?.codec_type !== 'audio'
    || !Number.isFinite(duration) || duration <= 0 || duration > 300) {
    throw new Error('ASSET-AUDIO-PROBE-001');
  }
  return { duration };
};

const manifest = await readJson(resolve('content/public/asset-manifest.json'), 'Public asset manifest');
const content = await readJson(resolve('content/public/portfolio-content.json'), 'Portfolio content');
if (!Array.isArray(manifest?.assets)) throw new Error('Public asset manifest is invalid.');

const assetClassById = new Map();
for (const project of [...(content.projects?.selected ?? []), ...(content.projects?.additional ?? [])]) {
  for (const media of project.media ?? []) {
    assetClassById.set(media.assetId, media.kind === 'chart' ? 'chart' : 'project-still');
    if (media.posterAssetId) assetClassById.set(media.posterAssetId, 'project-still');
    if (media.fallbackAssetId) assetClassById.set(media.fallbackAssetId, 'project-still');
  }
  for (const assetId of project.assetIds ?? []) if (!assetClassById.has(assetId)) assetClassById.set(assetId, 'project-still');
}
for (const group of content.toolkit ?? []) for (const technology of group.technologies ?? []) {
  if (technology.assetId) assetClassById.set(technology.assetId, 'project-still');
}
if (content.metadata?.socialPreviewAssetId) assetClassById.set(content.metadata.socialPreviewAssetId, 'project-still');
if (content.soundtrack) {
  for (const region of [
    content.soundtrack.intro,
    content.soundtrack.main,
    content.soundtrack.afterglow,
    content.soundtrack.driveLift,
  ]) {
    if (region?.opusAssetId) assetClassById.set(region.opusAssetId, 'soundtrack-audio');
    if (region?.mp3AssetId) assetClassById.set(region.mp3AssetId, 'soundtrack-audio');
  }
}

const manifestByPath = new Map(manifest.assets.map((asset) => [`assets/${asset.fileName}`, asset]));
const records = [];
const mediaViolations = [];
for (const absolute of await listFiles(root)) {
  const path = relative(root, absolute).split(sep).join('/');
  const bytes = await readFile(absolute);
  const source = /\.(?:css|html|js|json|txt|xml)$/u.test(path) ? bytes.toString('utf8') : '';
  const manifestAsset = manifestByPath.get(path);
  let bucket;
  if (manifestAsset !== undefined) {
    const digest = createHash('sha256').update(bytes).digest('hex');
    if (digest !== manifestAsset.sha256) throw new Error(`Published asset hash mismatch: ${path}`);
    const mediaType = manifestAsset.mediaType;
    const detected = await fileTypeFromBuffer(bytes);
    const detectedMediaType = normalizeDetectedMediaType(detected?.mime)
      ?? (/^\s*<svg[\s>]/u.test(bytes.toString('utf8', 0, Math.min(bytes.length, 256))) ? 'image/svg+xml' : null);
    if (detectedMediaType !== mediaType) throw new Error(`Manifest media type disagrees with deterministic probing: ${manifestAsset.id}`);
    let probe;
    if (mediaType?.startsWith('video/')) {
      const video = await probeVideo(absolute, { allowAudio: false });
      probe = { mediaType, width: video.width, height: video.height, durationMs: Math.round(video.duration * 1_000) };
      bucket = 'project-video';
    } else if (mediaType?.startsWith('image/')) {
      const image = await sharp(absolute, { failOn: 'error', limitInputPixels: 50_000_000 }).metadata();
      probe = { mediaType, width: image.width, height: image.height, durationMs: null };
      bucket = assetClassById.get(manifestAsset.id) === 'chart' ? 'chart' : 'project-still';
    } else if (mediaType?.startsWith('audio/')) {
      const audio = await probeAudio(absolute);
      probe = { mediaType, width: null, height: null, durationMs: Math.round(audio.duration * 1_000) };
      bucket = 'soundtrack-audio';
    } else {
      throw new Error(`Manifest asset has unsupported media type: ${manifestAsset.id}`);
    }
    mediaViolations.push(...evaluateMediaAssetBudget(
      manifestAsset,
      probe,
      compressedSize(path, bytes),
      bucket === 'chart' ? 'chart' : bucket === 'soundtrack-audio' ? 'soundtrack-audio' : 'project-still',
    ).violations);
  } else {
    bucket = classifyArtifact(path, source);
    if (['project-video', 'project-still', 'chart', 'soundtrack-audio'].includes(bucket)) {
      throw new Error(`Project media must be present in the public asset manifest: ${path}`);
    }
  }
  records.push({ path, bucket, bytes: bytes.byteLength, transferBytes: compressedSize(path, bytes) });
}
for (const path of manifestByPath.keys()) if (!records.some((record) => record.path === path)) throw new Error(`Manifest asset is missing from the build: ${path}`);

const sum = (bucket) => records.filter((record) => record.bucket === bucket).reduce((total, record) => total + record.transferBytes, 0);
const totals = {
  initialHtmlCriticalCss: sum('initial-html') + sum('critical-css'),
  initialApplicationJs: sum('initial-application-js'),
  heroPoster: sum('hero-poster'),
  initialFonts: sum('initial-fonts'),
  firstLiveScene: sum('first-live-scene'),
  deferredProjectVisuals: sum('project-still') + sum('chart'),
  highTierExtras: sum('high-tier-extras'),
  deferredNonVideo: sum('first-live-scene') + sum('high-tier-extras') + sum('project-still') + sum('chart'),
  deferredAudio: sum('soundtrack-audio'),
};

const entry = records.find((record) => record.bucket === 'initial-application-js');
const scene = records.find((record) => record.bucket === 'first-live-scene');
if (entry === undefined || scene === undefined) throw new Error('Both initial application and deferred live-scene chunks are required.');
const entrySource = await readFile(resolve(root, entry.path), 'utf8');
if (!/import\([^)]*environment-/u.test(entrySource)) throw new Error('The live scene is not separated behind a dynamic import.');
if (/WebGLRenderer|WebGLProgram|ShaderMaterial/u.test(entrySource)) throw new Error('Three.js/live-scene code leaked into the reduced-motion initial chunk.');

let runtime = null;
if (gateMode.kind === 'full') {
  const trace = await readJson(resolve(gateMode.runtimeTracePath), 'Runtime drive trace');
  runtime = validateRuntimeBudgetTraceReport(trace);
}
const violations = [...evaluateBudgetTotals(totals).violations, ...mediaViolations, ...(runtime?.violations ?? [])];
const report = {
  schema: 'portfolio-bundle-budget/v1',
  compression: 'brotli-quality-11-or-raw-already-compressed',
  totals,
  runtime: runtime === null
    ? { status: 'transfer-only-non-gating', gating: false, runtimeEvidence: 'pending' }
    : { status: 'verified-production-path-trace', gating: true, tier: runtime.tier },
  records: records.sort((left, right) => left.path.localeCompare(right.path)),
  violations,
};
process.stdout.write(`${JSON.stringify(report, null, 2)}\n`);
if (violations.length > 0) process.exitCode = 1;