const path = require('path');
const fsp = require('fs/promises');
const ExifReader = require('exifreader');
const sharp = require('sharp');
const { sha256, inferMimeFromExt, parseExifDateUtc } = require('./utils');
const { extractGpsFromExif, extractGpsWithExiftool } = require('./gps');
const { createVideoThumbnail, createThumbnails } = require('./thumbs');
const { probeVideo } = require('./video');
const loc = require('../geo.js');
const { WEB_ROOT, PATH_FULL } = require('../config');
const { getElevation } = require('./elevation');


async function processFile(userName, cartella, fileRelPath, absPath, ext, st) {
  const isVideo = ['.mp4', '.mov', '.m4v'].includes(ext);

  const thumbBase = path.join(
    WEB_ROOT,
    'photos',
    userName,
    'thumbs',
    cartella,
    path.dirname(fileRelPath)
  );

  await fsp.mkdir(thumbBase, { recursive: true });

  // --- Nome file + estensione (dal path ASSOLUTO, sempre corretto) ---
  const parsed = path.parse(absPath);
  const baseName = parsed.name;   // IMG_0249
  const extName  = parsed.ext;    // .JPG

  const absThumbMin = path.join(thumbBase, `${baseName}_min.jpg`);
  const absThumbAvg = path.join(thumbBase, `${baseName}_avg.jpg`);

  if (isVideo) {
    await createVideoThumbnail(absPath, absThumbMin, absThumbAvg);
  } else {
    await createThumbnails(absPath, absThumbMin, absThumbAvg);
  }

  // --- EXIF ---
  let tags = {};
  try {
    tags = await ExifReader.load(absPath, { expanded: true });
  } catch {}

let timeRaw = tags?.exif?.DateTimeOriginal?.value?.[0] || null;
let takenAtIso = parseExifDateUtc(timeRaw);

// Fallback per i video
if (isVideo) {
  const fallback = new Date(st.mtimeMs).toISOString();
  takenAtIso = fallback;
  timeRaw = fallback;
}


// --- GPS ---
let gps = null;

if (isVideo) {
  // i video usano exiftool
  gps = await extractGpsWithExiftool(absPath);
} else {
  // le foto usano exifreader
  gps = extractGpsFromExif(tags);
}

// --- ALTITUDINE DA SERVIZIO ESTERNO SE MANCANTE ---
if (gps && gps.lat && gps.lng) {
  if (gps.alt == null) {
    gps.alt = await getElevation(gps.lat, gps.lng);
  }
}



  // --- DIMENSIONI & ROTAZIONE ---
  let width = null, height = null, duration = null, duration_ms = null, rotation = 0;

  if (isVideo) {
    const info = await probeVideo(absPath);
    const stream = info.streams?.find(s => s.width && s.height);

    if (stream) {
      width = stream.width;
      height = stream.height;

      rotation = 0;

      if (stream?.tags?.rotate) {
        rotation = Number(stream.tags.rotate);
      }

      const sdl = stream?.side_data_list;
      if (sdl && Array.isArray(sdl)) {
        const rotEntry = sdl.find(d => d.rotation !== undefined);
        if (rotEntry) rotation = Number(rotEntry.rotation);

        const matrixEntry = sdl.find(d => typeof d.displaymatrix === 'string');
        if (matrixEntry) {
          const match = matrixEntry.displaymatrix.match(/rotation of ([\-0-9]+) degrees/i);
          if (match) rotation = Number(match[1]);
        }
      }

      rotation = ((rotation % 360) + 360) % 360;
    }

    duration = info.format?.duration || null;
    duration_ms = duration ? Math.round(duration * 1000) : null;

  } else {
    try {
      const meta = await sharp(absPath).metadata();
      width = meta.width || null;
      height = meta.height || null;
    } catch {}

    try {
      const raw =
        tags?.exif?.Orientation?.value ??
        tags?.image?.Orientation?.value ??
        tags?.ifd0?.Orientation?.value ??
        null;

      const val = Array.isArray(raw) ? raw[0] : raw;

      const map = { 1: 0, 3: 180, 6: 90, 8: 270 };
      rotation = map[val] ?? 0;
    } catch {}
  }

  const mime_type = inferMimeFromExt(ext);
  const id = sha256(`${userName}/${cartella}/${fileRelPath}`);

  const location = gps ? await loc(gps.lng, gps.lat) : null;

  //
  // --- GESTIONE PATH FULL / RELATIVI ---
  //

  const relPath = fileRelPath;
  const relThub1 = fileRelPath.replace(/\.[^.]+$/, '_min.jpg');
  const relThub2 = fileRelPath.replace(/\.[^.]+$/, '_avg.jpg');

  const fullPath = PATH_FULL
    ? path.posix.join('/photos', userName, cartella, fileRelPath)
    : relPath;

  const fullThub1 = PATH_FULL
    ? path.posix.join('/photos', userName, 'thumbs', cartella, relThub1)
    : relThub1;

  const fullThub2 = PATH_FULL
    ? path.posix.join('/photos', userName, 'thumbs', cartella, relThub2)
    : relThub2;

  return {
    id,
    user: userName,
    cartella,
    name: baseName + extName,   // 👈 SEMPRE CORRETTO
    path: fullPath,
    thub1: fullThub1,
    thub2: fullThub2,
    gps,
    data: timeRaw,
    taken_at: takenAtIso,
    mime_type,
    width,
    height,
    rotation,
    size_bytes: st.size,
    mtimeMs: st.mtimeMs,
    duration_ms: isVideo ? duration_ms : null,
    location
  };
}

module.exports = processFile;