import { connectMongo } from "./db.js";

const COLLECTION = "tv_data";
const TVDB_KEY_PREFIX = "tvdb-";

function canonicalTvdbKey(tvdbId) {
  if (tvdbId === null || tvdbId === undefined) return null;
  return `${TVDB_KEY_PREFIX}${tvdbId}`;
}

async function getCollection() {
  const { db } = await connectMongo();
  const col = db.collection(COLLECTION);
  await col.createIndex({ rootFolder: 1 });
  await col.createIndex({ rootFolders: 1 });
  await col.createIndex({ tvdbId: 1 }, { sparse: true });
  await col.createIndex({ updatedAt: -1 });
  return col;
}

function buildDocument(key, rootFolder, seriesData) {
  const tvdbId = seriesData?.id ?? seriesData?.tvdbId ?? null;
  return {
    _id: key,
    key,
    rootFolder,
    rootFolders: rootFolder ? [rootFolder] : [],
    tvdbId,
    name: seriesData?.name || null,
    data: seriesData || {},
    updatedAt: Date.now()
  };
}

export async function upsertTvSeries(key, rootFolder, seriesData) {
  const col = await getCollection();
  const tvdbId = seriesData?.id ?? seriesData?.tvdbId ?? null;
  const canonicalKey = tvdbId !== null ? canonicalTvdbKey(tvdbId) : null;
  const targetKey = canonicalKey || key;

  const existingByTvdb =
    tvdbId !== null ? await col.findOne({ tvdbId }) : null;
  const existing =
    existingByTvdb ||
    (await col.findOne({ _id: targetKey })) ||
    (await col.findOne({ _id: key }));

  const desiredKey = canonicalKey || existingByTvdb?._id || targetKey;
  const doc = buildDocument(
    desiredKey,
    rootFolder || existing?.rootFolder,
    seriesData
  );

  const rootSet = new Set(existing?.rootFolders || []);
  if (existing?.rootFolder) rootSet.add(existing.rootFolder);
  if (rootFolder) rootSet.add(rootFolder);
  doc.rootFolders = Array.from(rootSet);
  doc.rootFolder = doc.rootFolder || doc.rootFolders[0] || null;
  doc.tvdbId = tvdbId;
  doc.key = canonicalKey || doc._id;
  doc._id = doc.key;

  await col.updateOne({ _id: doc._id }, { $set: doc }, { upsert: true });

  // Eğer eski bir anahtar farklıysa temizle
  if (existing && existing._id !== doc._id) {
    await col.deleteOne({ _id: existing._id }).catch(() => {});
  }

  return doc.data;
}

export async function getTvSeriesByKey(key) {
  const col = await getCollection();
  const doc = await col.findOne({ _id: key });
  return doc?.data || null;
}

export async function getTvSeriesByRoot(rootFolder) {
  const col = await getCollection();
  const docs = await col
    .find({
      $or: [{ rootFolder }, { rootFolders: rootFolder }]
    })
    .toArray();
  return docs.map((doc) => ({
    key: doc.key,
    rootFolder: doc.rootFolder,
    rootFolders: doc.rootFolders || [],
    data: doc.data
  }));
}

export async function listAllTvSeries() {
  const col = await getCollection();
  const docs = await col.find({}).toArray();
  return docs.map((doc) => ({
    key: doc.key,
    rootFolder: doc.rootFolder,
    rootFolders: doc.rootFolders || [],
    data: doc.data
  }));
}

export async function listTvSeriesKeysForRoot(rootFolder) {
  const col = await getCollection();
  const docs = await col
    .find({
      $or: [{ rootFolder }, { rootFolders: rootFolder }]
    })
    .project({ key: 1 })
    .toArray();
  return docs.map((d) => d.key).filter(Boolean);
}

export async function removeTvSeriesByKey(key) {
  const col = await getCollection();
  await col.deleteOne({ _id: key });
}

export async function removeTvSeriesByRoot(rootFolder) {
  const col = await getCollection();
  const cursor = col.find({
    $or: [{ rootFolder }, { rootFolders: rootFolder }]
  });

  // Silmek yerine root'u listeden çıkar; boş kalırsa kaydı kaldır
  // Not: cursor.forEach async callback desteklemez, manual loop
  while (await cursor.hasNext()) {
    const doc = await cursor.next();
    const roots = new Set(doc.rootFolders || []);
    if (doc.rootFolder) roots.add(doc.rootFolder);
    roots.delete(rootFolder);

    if (roots.size === 0) {
      await col.deleteOne({ _id: doc._id });
    } else {
      const nextRootFolder = Array.from(roots)[0];
      await col.updateOne(
        { _id: doc._id },
        {
          $set: {
            rootFolder: nextRootFolder,
            rootFolders: Array.from(roots),
            updatedAt: Date.now()
          }
        }
      );
    }
  }
}

export { canonicalTvdbKey };