import { Level } from 'level'
import { type GroupNotify, RawMessage } from '../ntqqapi/types'
import { DATA_DIR } from './utils'
import { selfInfo } from './data'
import { FileCache } from './types'
import { log } from './utils/log'

type ReceiveTempUinMap = Record<string, string>

class DBUtil {
  public readonly DB_KEY_PREFIX_MSG_ID = 'msg_id_'
  public readonly DB_KEY_PREFIX_MSG_SHORT_ID = 'msg_short_id_'
  public readonly DB_KEY_PREFIX_MSG_SEQ_ID = 'msg_seq_id_'
  public readonly DB_KEY_PREFIX_FILE = 'file_'
  public readonly DB_KEY_PREFIX_GROUP_NOTIFY = 'group_notify_'
  private readonly DB_KEY_RECEIVED_TEMP_UIN_MAP = 'received_temp_uin_map'
  public db: Level
  public cache: Record<string, RawMessage | string | FileCache | GroupNotify | ReceiveTempUinMap> = {} // <msg_id_ | msg_short_id_ | msg_seq_id_><id>: RawMessage
  private currentShortId: number

  /*
   * 数据库结构
   * msg_id_101231230999: {} // 长id: RawMessage
   * msg_short_id_1: 101231230999  // 短id: 长id
   * msg_seq_id_1: 101231230999  // 序列id: 长id
   * file_7827DBAFJFW2323.png: {} // 文件名: FileCache
   * */

  constructor() {
    let initCount = 0
    new Promise((resolve, reject) => {
      const initDB = () => {
        initCount++
        // if (initCount > 50) {
        //     return reject("init db fail")
        // }

        try {
          if (!selfInfo.uin) {
            setTimeout(initDB, 300)
            return
          }
          const DB_PATH = DATA_DIR + `/msg_${selfInfo.uin}`
          this.db = new Level(DB_PATH, { valueEncoding: 'json' })
          console.log('llonebot init db success')
          resolve(null)
        } catch (e) {
          console.log('init db fail', e.stack.toString())
          setTimeout(initDB, 300)
        }
      }
      setTimeout(initDB)
    }).then()

    const expiredMilliSecond = 1000 * 60 * 60

    setInterval(() => {
      // this.cache = {}
      // 清理时间较久的缓存
      const now = Date.now()
      for (let key in this.cache) {
        let message: RawMessage = this.cache[key] as RawMessage
        if (message?.msgTime) {
          if (now - parseInt(message.msgTime) * 1000 > expiredMilliSecond) {
            delete this.cache[key]
            // log("clear cache", key, message.msgTime);
          }
        }
      }
    }, expiredMilliSecond)
  }

  public async getReceivedTempUinMap(): Promise<ReceiveTempUinMap> {
    try {
      this.cache[this.DB_KEY_RECEIVED_TEMP_UIN_MAP] = JSON.parse(await this.db.get(this.DB_KEY_RECEIVED_TEMP_UIN_MAP))
    } catch (e) {}
    return (this.cache[this.DB_KEY_RECEIVED_TEMP_UIN_MAP] || {}) as ReceiveTempUinMap
  }
  public setReceivedTempUinMap(data: ReceiveTempUinMap) {
    this.cache[this.DB_KEY_RECEIVED_TEMP_UIN_MAP] = data
    this.db.put(this.DB_KEY_RECEIVED_TEMP_UIN_MAP, JSON.stringify(data)).then()
  }
  private addCache(msg: RawMessage) {
    const longIdKey = this.DB_KEY_PREFIX_MSG_ID + msg.msgId
    const shortIdKey = this.DB_KEY_PREFIX_MSG_SHORT_ID + msg.msgShortId
    const seqIdKey = this.DB_KEY_PREFIX_MSG_SEQ_ID + msg.msgSeq
    this.cache[longIdKey] = this.cache[shortIdKey] = msg
  }

  public clearCache() {
    this.cache = {}
  }

  async getMsgByShortId(shortMsgId: number): Promise<RawMessage> {
    const shortMsgIdKey = this.DB_KEY_PREFIX_MSG_SHORT_ID + shortMsgId
    if (this.cache[shortMsgIdKey]) {
      // log("getMsgByShortId cache", shortMsgIdKey, this.cache[shortMsgIdKey])
      return this.cache[shortMsgIdKey] as RawMessage
    }
    try {
      const longId = await this.db.get(shortMsgIdKey)
      const msg = await this.getMsgByLongId(longId)
      this.addCache(msg)
      return msg
    } catch (e) {
      log('getMsgByShortId db error', e.stack.toString())
    }
  }

  async getMsgByLongId(longId: string): Promise<RawMessage> {
    const longIdKey = this.DB_KEY_PREFIX_MSG_ID + longId
    if (this.cache[longIdKey]) {
      return this.cache[longIdKey] as RawMessage
    }
    try {
      const data = await this.db.get(longIdKey)
      const msg = JSON.parse(data)
      this.addCache(msg)
      return msg
    } catch (e) {
      // log("getMsgByLongId db error", e.stack.toString())
    }
  }

  async getMsgBySeqId(seqId: string): Promise<RawMessage> {
    const seqIdKey = this.DB_KEY_PREFIX_MSG_SEQ_ID + seqId
    if (this.cache[seqIdKey]) {
      return this.cache[seqIdKey] as RawMessage
    }
    try {
      const longId = await this.db.get(seqIdKey)
      const msg = await this.getMsgByLongId(longId)
      this.addCache(msg)
      return msg
    } catch (e) {
      log('getMsgBySeqId db error', e.stack.toString())
    }
  }

  async addMsg(msg: RawMessage) {
    // 有则更新，无则添加
    // log("addMsg", msg.msgId, msg.msgSeq, msg.msgShortId);
    const longIdKey = this.DB_KEY_PREFIX_MSG_ID + msg.msgId
    let existMsg = this.cache[longIdKey] as RawMessage
    if (!existMsg) {
      try {
        existMsg = await this.getMsgByLongId(msg.msgId)
      } catch (e) {
        // log("addMsg getMsgByLongId error", e.stack.toString())
      }
    }
    if (existMsg) {
      // log("消息已存在", existMsg.msgSeq, existMsg.msgShortId, existMsg.msgId)
      this.updateMsg(msg).then()
      return existMsg.msgShortId
    }
    this.addCache(msg)

    const shortMsgId = await this.genMsgShortId()
    const shortIdKey = this.DB_KEY_PREFIX_MSG_SHORT_ID + shortMsgId
    const seqIdKey = this.DB_KEY_PREFIX_MSG_SEQ_ID + msg.msgSeq
    msg.msgShortId = shortMsgId
    // log("新增消息记录", msg.msgId)
    this.db.put(shortIdKey, msg.msgId).then().catch()
    this.db.put(longIdKey, JSON.stringify(msg)).then().catch()
    try {
      await this.db.get(seqIdKey)
    } catch (e) {
      // log("新的seqId", seqIdKey)
      this.db.put(seqIdKey, msg.msgId).then().catch()
    }
    if (!this.cache[seqIdKey]) {
      this.cache[seqIdKey] = msg
    }
    return shortMsgId
    // log(`消息入库 ${seqIdKey}: ${msg.msgId}, ${shortMsgId}: ${msg.msgId}`);
  }

  async updateMsg(msg: RawMessage) {
    const longIdKey = this.DB_KEY_PREFIX_MSG_ID + msg.msgId
    let existMsg = this.cache[longIdKey] as RawMessage
    if (!existMsg) {
      try {
        existMsg = await this.getMsgByLongId(msg.msgId)
      } catch (e) {
        existMsg = msg
      }
    }

    Object.assign(existMsg, msg)
    this.db.put(longIdKey, JSON.stringify(existMsg)).then().catch()
    const shortIdKey = this.DB_KEY_PREFIX_MSG_SHORT_ID + existMsg.msgShortId
    const seqIdKey = this.DB_KEY_PREFIX_MSG_SEQ_ID + msg.msgSeq
    if (!this.cache[seqIdKey]) {
      this.cache[seqIdKey] = existMsg
    }
    this.db.put(shortIdKey, msg.msgId).then().catch()
    try {
      await this.db.get(seqIdKey)
    } catch (e) {
      this.db.put(seqIdKey, msg.msgId).then().catch()
      // log("更新seqId error", e.stack, seqIdKey);
    }
    // log("更新消息", existMsg.msgSeq, existMsg.msgShortId, existMsg.msgId);
  }

  private async genMsgShortId(): Promise<number> {
    const key = 'msg_current_short_id'
    if (this.currentShortId === undefined) {
      try {
        let id: string = await this.db.get(key)
        this.currentShortId = parseInt(id)
      } catch (e) {
        this.currentShortId = -2147483640
      }
    }

    this.currentShortId++
    this.db.put(key, this.currentShortId.toString()).then().catch()
    return this.currentShortId
  }

  async addFileCache(fileNameOrUuid: string, data: FileCache) {
    const key = this.DB_KEY_PREFIX_FILE + fileNameOrUuid
    if (this.cache[key]) {
      return
    }
    let cacheDBData = { ...data }
    delete cacheDBData['downloadFunc']
    this.cache[fileNameOrUuid] = data
    try {
      await this.db.put(key, JSON.stringify(cacheDBData))
    } catch (e) {
      log('addFileCache db error', e.stack.toString())
    }
  }

  async getFileCache(fileNameOrUuid: string): Promise<FileCache | undefined> {
    const key = this.DB_KEY_PREFIX_FILE + fileNameOrUuid
    if (this.cache[key]) {
      return this.cache[key] as FileCache
    }
    try {
      let data = await this.db.get(key)
      return JSON.parse(data)
    } catch (e) {
      // log("getFileCache db error", e.stack.toString())
    }
  }

  async addGroupNotify(notify: GroupNotify) {
    const key = this.DB_KEY_PREFIX_GROUP_NOTIFY + notify.seq
    let existNotify = this.cache[key] as GroupNotify
    if (existNotify) {
      return
    }
    this.cache[key] = notify
    this.db.put(key, JSON.stringify(notify)).then().catch()
  }

  async getGroupNotify(seq: string): Promise<GroupNotify | undefined> {
    const key = this.DB_KEY_PREFIX_GROUP_NOTIFY + seq
    if (this.cache[key]) {
      return this.cache[key] as GroupNotify
    }
    try {
      let data = await this.db.get(key)
      return JSON.parse(data)
    } catch (e) {
      // log("getGroupNotify db error", e.stack.toString())
    }
  }
}

export const dbUtil = new DBUtil()