#!/usr/bin/env node
/**
 * Compress sweets modal videos → uniform 640×480 (4:3), ≤ 200 KB, no audio.
 * Usage:
 *   node scripts/optimize-sweets-videos.mjs
 *   node scripts/optimize-sweets-videos.mjs public/videos/badam-barfi.mp4
 */
import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';
import { spawnSync } from 'child_process';
import ffmpegPath from 'ffmpeg-static';

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const ROOT = path.join(__dirname, '..');
const VIDEOS_DIR = path.join(ROOT, 'public/videos');
const MENU_DATA = path.join(ROOT, 'infrastructure/menu/static-menu-data.ts');
const REPORT_PATH = path.join(__dirname, 'sweets-videos-optimize-report.json');

const MAX_BYTES = 200 * 1024;
const TARGET_WIDTH = 640;
const TARGET_HEIGHT = 480;

/** Sweets dish ids with video fields in menu data */
function getSweetsVideoFiles() {
  const content = fs.readFileSync(MENU_DATA, 'utf8');
  const sweetsIdx = content.indexOf('id: "sweets"');
  const itemsStart = content.indexOf('items: [', sweetsIdx);
  let depth = 0;
  let itemsEnd = -1;
  for (let i = itemsStart + 7; i < content.length; i++) {
    if (content[i] === '[') depth++;
    else if (content[i] === ']') {
      depth--;
      if (depth === 0) {
        itemsEnd = i;
        break;
      }
    }
  }
  const block = content.slice(itemsStart, itemsEnd + 1);
  return [...block.matchAll(/video:\s*"([^"]+\.mp4)"/g)].map((m) => m[1]);
}

function compressVideo(inputPath, outputPath, { crf, fps, width, height }) {
  const vf = `scale=${width}:${height}:force_original_aspect_ratio=increase,crop=${width}:${height},fps=${fps}`;
  const result = spawnSync(
    ffmpegPath,
    [
      '-y',
      '-i', inputPath,
      '-an',
      '-vf', vf,
      '-c:v', 'libx264',
      '-preset', 'medium',
      '-profile:v', 'baseline',
      '-level', '3.0',
      '-pix_fmt', 'yuv420p',
      '-movflags', '+faststart',
      '-crf', String(crf),
      outputPath,
    ],
    { stdio: 'pipe' },
  );
  return result.status === 0 && fs.existsSync(outputPath);
}

function optimizeOne(inputPath) {
  if (!fs.existsSync(inputPath)) return { skipped: true, reason: 'missing' };

  const temp = `${inputPath}.opt.tmp.mp4`;
  const attempts = [
    { crf: 34, fps: 24, width: TARGET_WIDTH, height: TARGET_HEIGHT },
    { crf: 36, fps: 20, width: TARGET_WIDTH, height: TARGET_HEIGHT },
    { crf: 38, fps: 18, width: TARGET_WIDTH, height: TARGET_HEIGHT },
    { crf: 40, fps: 15, width: 560, height: 420 },
    { crf: 42, fps: 12, width: 480, height: 360 },
    { crf: 44, fps: 10, width: 400, height: 300 },
  ];

  let best = null;

  for (const opts of attempts) {
    if (fs.existsSync(temp)) fs.unlinkSync(temp);
    if (!compressVideo(inputPath, temp, opts)) continue;

    const bytes = fs.statSync(temp).size;
    const entry = { ...opts, bytes, kb: Number((bytes / 1024).toFixed(1)) };

    if (bytes <= MAX_BYTES) {
      fs.renameSync(temp, inputPath);
      return { ok: true, ...entry, warning: null };
    }

    if (!best || bytes < best.bytes) best = entry;
  }

  if (best && fs.existsSync(temp)) {
    fs.renameSync(temp, inputPath);
    return { ok: true, ...best, warning: 'exceeds-200kb' };
  }

  if (fs.existsSync(temp)) fs.unlinkSync(temp);
  return { ok: false, reason: 'encode-failed' };
}

function main() {
  if (!ffmpegPath) throw new Error('ffmpeg-static not available');

  const arg = process.argv[2];
  const files = arg
    ? [path.basename(arg).endsWith('.mp4') ? path.basename(arg) : `${arg}.mp4`]
    : getSweetsVideoFiles();

  console.log('Shahi Kitchen — sweets video optimize');
  console.log(`Target: ${TARGET_WIDTH}×${TARGET_HEIGHT}, ≤ ${MAX_BYTES / 1024} KB\n`);

  const results = [];

  for (const file of files) {
    const fullPath = path.join(VIDEOS_DIR, file);
    const before = fs.existsSync(fullPath) ? fs.statSync(fullPath).size : 0;
    const r = optimizeOne(fullPath);

    if (r.skipped) {
      console.log(`⚠ skip ${file} (${r.reason})`);
      results.push({ file, skipped: true, reason: r.reason });
      continue;
    }
    if (!r.ok) {
      console.log(`✗ ${file} (${r.reason})`);
      results.push({ file, ok: false, reason: r.reason });
      continue;
    }

    const after = fs.statSync(fullPath).size;
    const warn = r.warning ? ' ⚠' : '';
    console.log(
      `✓ ${file}: ${(before / 1024).toFixed(0)} KB → ${(after / 1024).toFixed(1)} KB ` +
        `(${r.width}×${r.height}, crf ${r.crf}, ${r.fps}fps)${warn}`,
    );
    results.push({
      file,
      ok: true,
      beforeKb: Number((before / 1024).toFixed(1)),
      afterKb: Number((after / 1024).toFixed(1)),
      width: r.width,
      height: r.height,
      crf: r.crf,
      fps: r.fps,
      warning: r.warning,
    });
  }

  fs.writeFileSync(REPORT_PATH, JSON.stringify({ generatedAt: new Date().toISOString(), results }, null, 2));
  console.log(`\nReport: ${REPORT_PATH}`);
}

main();