import sharp from 'sharp';
import type { Note, NoteDetail, ImageWithAnnotations, ReviewStatus } from '../../shared/types.js';
import { notesRepository } from '../repositories/notesRepository.js';
import { imagesRepository } from '../repositories/imagesRepository.js';
import { annotationsRepository } from '../repositories/annotationsRepository.js';
import { database, withTransaction } from '../database.js';
import { storeUploadedFile } from '../storage.js';
import { recalculateCollectionStatus } from './collectionsService.js';

export interface UploadedFile { filename: string; originalname?: string; mimetype?: string; path: string }

async function readImageSize(filePath: string): Promise<{ width: number; height: number }> {
  try { const meta = await sharp(filePath).metadata(); return { width: meta.width ?? 0, height: meta.height ?? 0 }; }
  catch { return { width: 0, height: 0 }; }
}

async function prepareFiles(files: UploadedFile[]) {
  return Promise.all(files.map(async (file) => ({ ...(await readImageSize(file.path)), ...(await storeUploadedFile(file)) })));
}

export const notesService = {
  async list(query: { sort?: string; order?: string; q?: string; collectionId?: number; status?: ReviewStatus; tag?: string; projectId?: number; groupId?: number; externalId?: string }) {
    return notesRepository.list({ sort: query.sort === 'annotations' ? 'annotations' : 'created_at', order: query.order === 'asc' ? 'asc' : 'desc', q: query.q, collectionId: query.collectionId, status: query.status, tag: query.tag, projectId: query.projectId, groupId: query.groupId, externalId: query.externalId });
  },

  async getDetail(id: number, requestedVersion?: number): Promise<NoteDetail | null> {
    const current = await notesRepository.findById(id);
    if (!current) return null;
    const selectedVersion = requestedVersion && requestedVersion !== current.version_number
      ? await database.one<{ version_number: number; title: string; description: string; tags: string; review_status: ReviewStatus }>('SELECT version_number, title, description, tags, review_status FROM work_versions WHERE note_id = ? AND version_number = ?', [id, requestedVersion])
      : undefined;
    if (requestedVersion && requestedVersion !== current.version_number && !selectedVersion) return null;
    const note: Note = selectedVersion ? { ...current, ...selectedVersion, version_number: Number(selectedVersion.version_number), tags: JSON.parse(selectedVersion.tags || '[]') as string[] } : current;
    const images = await imagesRepository.listByNote(id, note.version_number);
    const workContext = await database.one<{ project_id: number; project_name: string; slug: string; collection_id: number; collection_name: string; collection_status: NoteDetail['collection']['status'] }>(`SELECT p.id AS project_id, p.name AS project_name, p.slug, c.id AS collection_id, c.name AS collection_name, c.status AS collection_status FROM notes n JOIN collections c ON c.id = n.collection_id JOIN projects p ON p.id = c.project_id WHERE n.id = ?`, [id]);
    if (!workContext) return null;
    const versionRows = await database.all<Array<Omit<NoteDetail['versions'][number], 'tags'> & { tags: string }>[number]>('SELECT version_number, title, description, tags, review_status, created_at FROM work_versions WHERE note_id = ? ORDER BY version_number DESC', [id]);
    const result: NoteDetail = {
      ...note,
      images: [] as ImageWithAnnotations[],
      text_annotations: await database.all<NoteDetail['text_annotations'][number]>('SELECT id, note_id, version_number, target, content, author_name, status, created_at FROM text_annotations WHERE note_id = ? AND version_number = ? ORDER BY id ASC', [id, note.version_number]),
      comments: await database.all<NoteDetail['comments'][number]>('SELECT * FROM work_comments WHERE note_id = ? ORDER BY id ASC', [id]),
      versions: versionRows.map((item) => ({ ...item, version_number: Number(item.version_number), tags: JSON.parse(item.tags || '[]') as string[] })),
      review_events: await database.all<NoteDetail['review_events'][number]>('SELECT * FROM review_events WHERE note_id = ? ORDER BY id DESC', [id]),
      project: { id: Number(workContext.project_id), name: workContext.project_name, slug: workContext.slug },
      collection: { id: Number(workContext.collection_id), name: workContext.collection_name, status: workContext.collection_status },
    };
    for (const image of images) result.images.push({ ...image, annotations: await annotationsRepository.listByImage(image.id) });
    return result;
  },

  async create(title: string, description: string, files: UploadedFile[], collectionId: number, tags: string[], externalId: string | null = null): Promise<Note> {
    const prepared = await prepareFiles(files);
    const noteId = await withTransaction(async (tx) => {
      const id = await tx.insertId('INSERT INTO notes (external_id, title, description, collection_id, tags, review_status) VALUES (?, ?, ?, ?, ?, ?)', [externalId, title, description, collectionId, JSON.stringify(tags), 'pending']);
      await imagesRepository.createMany(id, prepared, 1, tx);
      await tx.execute("INSERT INTO work_versions (note_id, version_number, title, description, tags, review_status) VALUES (?, 1, ?, ?, ?, 'pending')", [id, title, description, JSON.stringify(tags)]);
      await recalculateCollectionStatus(collectionId, tx);
      return id;
    });
    return (await notesRepository.findById(noteId))!;
  },

  async createFromUrls(title: string, description: string, imageUrls: string[], collectionId: number, tags: string[], externalId: string | null = null): Promise<Note> {
    const noteId = await withTransaction(async (tx) => {
      const id = await tx.insertId('INSERT INTO notes (external_id, title, description, collection_id, tags, review_status) VALUES (?, ?, ?, ?, ?, ?)', [externalId, title, description, collectionId, JSON.stringify(tags), 'pending']);
      await imagesRepository.createMany(id, imageUrls.map((url) => ({ url, width: 0, height: 0, storageProvider: 'external' as const, storageKey: '' })), 1, tx);
      await tx.execute("INSERT INTO work_versions (note_id, version_number, title, description, tags, review_status) VALUES (?, 1, ?, ?, ?, 'pending')", [id, title, description, JSON.stringify(tags)]);
      await recalculateCollectionStatus(collectionId, tx);
      return id;
    });
    return (await notesRepository.findById(noteId))!;
  },

  async findByExternalId(collectionId: number, externalId: string): Promise<Note | null> {
    return notesRepository.findByExternalId(collectionId, externalId);
  },

  async createVersion(id: number, title: string, description: string, files: UploadedFile[], tags: string[], createdBy?: number): Promise<Note> {
    const current = await notesRepository.findById(id);
    if (!current) throw new Error('作品不存在');
    const nextVersion = current.version_number + 1;
    const prepared = await prepareFiles(files);
    await withTransaction(async (tx) => {
      await tx.execute("UPDATE notes SET title = ?, description = ?, tags = ?, version_number = ?, review_status = 'pending' WHERE id = ?", [title, description, JSON.stringify(tags), nextVersion, id]);
      await tx.execute("INSERT INTO work_versions (note_id, version_number, title, description, tags, review_status, created_by) VALUES (?, ?, ?, ?, ?, 'pending', ?)", [id, nextVersion, title, description, JSON.stringify(tags), createdBy ?? null]);
      await imagesRepository.createMany(id, prepared, nextVersion, tx);
      await tx.execute("INSERT INTO review_events (note_id, version_number, event_type, from_status, to_status, actor_name, actor_role) VALUES (?, ?, 'submitted', ?, 'pending', ?, 'operator')", [id, nextVersion, current.review_status, '工作台']);
      await recalculateCollectionStatus(current.collection_id, tx);
    });
    return (await notesRepository.findById(id))!;
  },

  async createVersionFromUrls(id: number, title: string, description: string, imageUrls: string[], tags: string[], createdBy?: number): Promise<Note> {
    const current = await notesRepository.findById(id);
    if (!current) throw new Error('作品不存在');
    const nextVersion = current.version_number + 1;
    await withTransaction(async (tx) => {
      await tx.execute("UPDATE notes SET title = ?, description = ?, tags = ?, version_number = ?, review_status = 'pending' WHERE id = ?", [title, description, JSON.stringify(tags), nextVersion, id]);
      await tx.execute("INSERT INTO work_versions (note_id, version_number, title, description, tags, review_status, created_by) VALUES (?, ?, ?, ?, ?, 'pending', ?)", [id, nextVersion, title, description, JSON.stringify(tags), createdBy ?? null]);
      await imagesRepository.createMany(id, imageUrls.map((url) => ({ url, width: 0, height: 0, storageProvider: 'external' as const, storageKey: '' })), nextVersion, tx);
      await tx.execute("INSERT INTO review_events (note_id, version_number, event_type, from_status, to_status, actor_name, actor_role) VALUES (?, ?, 'submitted', ?, 'pending', ?, 'operator')", [id, nextVersion, current.review_status, '工作台']);
      await recalculateCollectionStatus(current.collection_id, tx);
    });
    return (await notesRepository.findById(id))!;
  },

  async remove(id: number) {
    return withTransaction(async (tx) => {
      const note = await tx.one<{ collection_id: number }>('SELECT collection_id FROM notes WHERE id = ?', [id]);
      if (!note) return false;
      const removed = (await tx.execute('DELETE FROM notes WHERE id = ?', [id])).changes > 0;
      if (removed) await recalculateCollectionStatus(Number(note.collection_id), tx);
      return removed;
    });
  },
  async setStatus(id: number, status: ReviewStatus) {
    return withTransaction(async (tx) => {
      const note = await tx.one<{ collection_id: number; version_number: number }>('SELECT collection_id, version_number FROM notes WHERE id = ?', [id]);
      if (!note) return false;
      await tx.execute('UPDATE notes SET review_status = ? WHERE id = ?', [status, id]);
      await tx.execute('UPDATE work_versions SET review_status = ? WHERE note_id = ? AND version_number = ?', [status, id, note.version_number]);
      await recalculateCollectionStatus(Number(note.collection_id), tx);
      return true;
    });
  },
};