/**
 * freemodel2api-ipc.ts — FreeModel2api(sub2api)会话的 IPC 边界。
 *
 * main 进程持有内存态 session(access token + 过期时间),不落盘;
 * 过期或 401 时用 safeStorage 里存的密码静默重登一次。
 * 密码本身永远不经过 renderer —— login 之后 renderer 只能拿到
 * email/balance/key 列表。
 */

import {
  Sub2ApiAuthError,
  loadFreeModel2ApiCredentials,
  loadRememberedLogin,
  normalizeSub2ApiBaseUrl,
  persistFreeModel2ApiCredentials,
  persistRememberedLogin,
  sub2ApiFetchKeys,
  sub2ApiFetchProfile,
  sub2ApiKeyBalance,
  sub2ApiLogin,
  type FetchLike,
  type FreeModel2ApiStoreIo
} from './freemodel2api'

export interface FreeModel2ApiIpcDeps {
  ipcMain: { handle: (channel: string, fn: (event: any, payload?: any) => Promise<any>) => void }
  io: FreeModel2ApiStoreIo
  fetcher: FetchLike
}

interface Session {
  baseUrl: string
  accessToken: string
  expiresAt: number
}

export function registerFreeModel2ApiIpc(deps: FreeModel2ApiIpcDeps): void {
  const { ipcMain, io, fetcher } = deps
  let session: Session | null = null

  async function freshLogin(baseUrl: string, email: string, password: string) {
    const result = await sub2ApiLogin(baseUrl, email, password, fetcher)
    session = { baseUrl: normalizeSub2ApiBaseUrl(baseUrl), accessToken: result.accessToken, expiresAt: result.expiresAt }
    return result
  }

  async function ensureSession(): Promise<Session> {
    if (session && session.expiresAt > Date.now()) {
      return session
    }
    const creds = loadFreeModel2ApiCredentials(io)
    if (!creds) {
      throw new Sub2ApiAuthError('FreeModel2api is not configured')
    }
    await freshLogin(creds.baseUrl, creds.email, creds.password)
    return session!
  }

  async function withSession<T>(fn: (s: Session) => Promise<T>): Promise<T> {
    const current = await ensureSession()
    try {
      return await fn(current)
    } catch (err) {
      if (!(err instanceof Sub2ApiAuthError)) throw err
      // token 可能已被服务端吊销:用已存密码重登一次再试
      const creds = loadFreeModel2ApiCredentials(io)
      if (!creds) throw err
      await freshLogin(creds.baseUrl, creds.email, creds.password)
      return fn(session!)
    }
  }

  ipcMain.handle('hermes:freemodel2api:login', async (_event, payload) => {
    const baseUrl = normalizeSub2ApiBaseUrl(String(payload?.baseUrl ?? ''))
    const email = String(payload?.email ?? '').trim()
    const password = String(payload?.password ?? '')
    if (!email || !password) {
      throw new Error('Email and password are required')
    }
    const result = await freshLogin(baseUrl, email, password)
    persistFreeModel2ApiCredentials({ baseUrl, email, password }, io)
    return {
      ok: true,
      email: result.email,
      balance: result.balance,
      username: result.username,
      frozenBalance: result.frozenBalance
    }
  })

  ipcMain.handle('hermes:freemodel2api:status', async () => {
    const creds = loadFreeModel2ApiCredentials(io)
    if (!creds) {
      return { configured: false }
    }
    const profile = await withSession(s => sub2ApiFetchProfile(s.baseUrl, s.accessToken, fetcher))
    return {
      configured: true,
      baseUrl: creds.baseUrl,
      email: profile.email || creds.email,
      balance: profile.balance,
      username: profile.username,
      frozenBalance: profile.frozenBalance
    }
  })

  ipcMain.handle('hermes:freemodel2api:keys', async () => {
    const keys = await withSession(s => sub2ApiFetchKeys(s.baseUrl, s.accessToken, fetcher))
    return { keys }
  })

  ipcMain.handle('hermes:freemodel2api:logout', async () => {
    session = null
    persistFreeModel2ApiCredentials(null, io)
    return { ok: true }
  })

  ipcMain.handle('hermes:freemodel2api:remembered:load', async () => {
    return loadRememberedLogin(io)
  })

  // 未登录的余额读数:凭 renderer 传来的 key 直查,不走会话。失败只报 null,不打扰人。
  ipcMain.handle('hermes:freemodel2api:key-balance', async (_event, payload) => {
    const baseUrl = String(payload?.baseUrl ?? '')
    const apiKey = String(payload?.apiKey ?? '')
    if (!baseUrl || !apiKey) {
      return { balance: null }
    }
    try {
      return { balance: await sub2ApiKeyBalance(baseUrl, apiKey, fetcher) }
    } catch {
      return { balance: null }
    }
  })

  ipcMain.handle('hermes:freemodel2api:remembered:save', async (_event, payload) => {
    if (!payload) {
      persistRememberedLogin(null, io)
      return { ok: true }
    }
    persistRememberedLogin(
      {
        baseUrl: normalizeSub2ApiBaseUrl(String(payload.baseUrl ?? '')),
        email: String(payload.email ?? '').trim(),
        password: String(payload.password ?? '')
      },
      io
    )
    return { ok: true }
  })
}