import { ipcMain, dialog, app } from 'electron'
import { copyFileSync, mkdirSync } from 'fs'
import { extname, join } from 'path'
import { IPC } from '../../../shared/ipc-channels'
import type { CreateBookParams, UpdateBookMetaParams } from '../../../shared/types'
import { BookRegistryService } from '../../services/book-registry'
import type { WritingSessionService } from '../../services/writing-session.service'
import { wrap } from '../result'

let previousBookId: string | null = null

export function registerBookHandlers(
  registry: BookRegistryService,
  writingSessions?: WritingSessionService
): void {
  ipcMain.handle(IPC.BOOK_LIST, () => wrap(() => registry.list()))

  ipcMain.handle(IPC.BOOK_CREATE, (_event, params: CreateBookParams) =>
    wrap(() => registry.create(params))
  )

  ipcMain.handle(IPC.BOOK_DELETE, (_event, { bookId }: { bookId: string }) =>
    wrap(() => {
      registry.delete(bookId)
    })
  )

  ipcMain.handle(IPC.BOOK_OPEN, (_event, { bookId }: { bookId: string }) =>
    wrap(() => {
      if (writingSessions && previousBookId && previousBookId !== bookId) {
        writingSessions.endActive(previousBookId)
      }
      previousBookId = bookId
      return registry.open(bookId)
    })
  )

  ipcMain.handle(
    IPC.BOOK_UPDATE_META,
    (_event, { bookId, ...patch }: { bookId: string } & UpdateBookMetaParams) =>
      wrap(() => registry.updateMeta(bookId, patch))
  )

  ipcMain.handle(IPC.BOOK_PICK_COVER, (_event, { bookId }: { bookId: string }) =>
    wrap(async () => {
      const { canceled, filePaths } = await dialog.showOpenDialog({
        filters: [{ name: 'Images', extensions: ['jpg', 'jpeg', 'png', 'webp'] }],
        properties: ['openFile']
      })
      if (canceled || !filePaths[0]) return null
      const src = filePaths[0]
      const ext = extname(src).toLowerCase() || '.jpg'
      const coversDir = join(app.getPath('userData'), 'covers')
      mkdirSync(coversDir, { recursive: true })
      const dest = join(coversDir, `${bookId}${ext}`)
      copyFileSync(src, dest)
      return registry.updateMeta(bookId, { coverPath: dest })
    })
  )
}