import { Mapper, PendingTickerInfoHelper } from './mapper'
import { Trade, BookChange, DerivativeTicker } from '../types'

// phemex provides timestamps in nanoseconds
const fromNanoSecondsToDate = (nanos: number) => {
  const microtimestamp = Math.floor(nanos / 1000)

  const timestamp = new Date(microtimestamp / 1000)
  timestamp.μs = microtimestamp % 1000

  return timestamp
}

function getPriceScale(symbol: string) {
  if (symbol.startsWith('s')) {
    return 1e8
  }

  return 1e4
}

function getQtyScale(symbol: string) {
  if (symbol.startsWith('s')) {
    return 1e8
  }

  return 1
}

const COINS_STARTING_WITH_S = ['SOL', 'SUSHI', 'SNX', 'SAND', 'SRM', 'SKLU', 'SXP', 'STORJ', 'SFP', 'STG']
function getInstrumentType(symbol: string) {
  if (/\d+$/.test(symbol)) {
    return 'future'
  }

  if (COINS_STARTING_WITH_S.some((c) => symbol.startsWith(c)) || symbol.startsWith('S') === false) {
    return 'perpetual'
  }

  return 'spot'
}

function getApiSymbolId(symbolId: string) {
  const type = getInstrumentType(symbolId)
  if (type === 'spot' && symbolId.startsWith('S')) {
    return symbolId.charAt(0).toLowerCase() + symbolId.slice(1)
  }
  if (symbolId.startsWith('U100')) {
    return symbolId.charAt(0).toLowerCase() + symbolId.slice(1)
  }

  if (symbolId === 'CETHUSD') {
    return symbolId.charAt(0).toLowerCase() + symbolId.slice(1)
  }

  return symbolId
}

function getSymbols(symbols: string[]) {
  const perpV2Symbols = symbols.filter((s) => getInstrumentType(s) === 'perpetual' && s.endsWith('USDT')).map(getApiSymbolId)
  const otherSymbols = symbols.filter((s) => getInstrumentType(s) !== 'perpetual' || s.endsWith('USDT') == false).map(getApiSymbolId)

  return {
    perpV2Symbols,
    otherSymbols
  }
}

export const phemexTradesMapper: Mapper<'phemex', Trade> = {
  canHandle(message: PhemexTradeMessage) {
    return message.type === 'incremental' && ('trades' in message || 'trades_p' in message)
  },

  getFilters(symbols?: string[]) {
    if (symbols == undefined || symbols.length === 0) {
      return [
        {
          channel: 'trades'
        } as const,
        {
          channel: 'trades_p'
        } as const
      ]
    }

    const { perpV2Symbols, otherSymbols } = getSymbols(symbols)

    const filters = []

    if (perpV2Symbols.length > 0) {
      filters.push({
        channel: 'trades_p',
        symbols: perpV2Symbols
      } as const)
    }
    if (otherSymbols.length > 0) {
      filters.push({
        channel: 'trades',
        symbols: otherSymbols
      } as const)
    }

    return filters
  },

  *map(message: PhemexTradeMessage, localTimestamp: Date): IterableIterator<Trade> {
    if ('trades' in message) {
      for (const [timestamp, side, priceEp, qty] of message.trades) {
        const symbol = message.symbol

        yield {
          type: 'trade',
          symbol: symbol.toUpperCase(),
          exchange: 'phemex',
          id: undefined,
          price: priceEp / getPriceScale(symbol),
          amount: qty / getQtyScale(symbol),
          side: side === 'Buy' ? 'buy' : 'sell',
          timestamp: fromNanoSecondsToDate(timestamp),
          localTimestamp: localTimestamp
        }
      }
    } else if ('trades_p' in message) {
      for (const [timestamp, side, price, qty] of message.trades_p) {
        const symbol = message.symbol

        yield {
          type: 'trade',
          symbol: symbol.toUpperCase(),
          exchange: 'phemex',
          id: undefined,
          price: Number(price),
          amount: Number(qty),
          side: side === 'Buy' ? 'buy' : 'sell',
          timestamp: fromNanoSecondsToDate(timestamp),
          localTimestamp: localTimestamp
        }
      }
    }
  }
}

const mapBookLevelForSymbol =
  (symbol: string) =>
  ([priceEp, qty]: PhemexBookLevel) => {
    return {
      price: priceEp / getPriceScale(symbol),
      amount: qty / getQtyScale(symbol)
    }
  }

function mapPerpBookLevel([price, amount]: [string, string]) {
  return {
    price: Number(price),
    amount: Number(amount)
  }
}

export const phemexBookChangeMapper: Mapper<'phemex', BookChange> = {
  canHandle(message: PhemexBookMessage) {
    return 'book' in message || 'orderbook_p' in message
  },

  getFilters(symbols?: string[]) {
    if (symbols == undefined || symbols.length === 0) {
      return [
        {
          channel: 'book'
        } as const,
        {
          channel: 'orderbook_p'
        } as const
      ]
    }

    const { perpV2Symbols, otherSymbols } = getSymbols(symbols)
    const filters = []

    if (perpV2Symbols.length > 0) {
      filters.push({
        channel: 'orderbook_p',
        symbols: perpV2Symbols
      } as const)
    }
    if (otherSymbols.length > 0) {
      filters.push({
        channel: 'book',
        symbols: otherSymbols
      } as const)
    }

    return filters
  },

  *map(message: PhemexBookMessage, localTimestamp: Date): IterableIterator<BookChange> {
    const symbol = message.symbol
    if ('book' in message) {
      const mapBookLevel = mapBookLevelForSymbol(symbol)
      yield {
        type: 'book_change',
        symbol: symbol.toUpperCase(),
        exchange: 'phemex',
        isSnapshot: message.type === 'snapshot',
        bids: message.book.bids.map(mapBookLevel),
        asks: message.book.asks.map(mapBookLevel),

        timestamp: fromNanoSecondsToDate(message.timestamp),
        localTimestamp
      }
    } else if ('orderbook_p' in message) {
      yield {
        type: 'book_change',
        symbol: symbol.toUpperCase(),
        exchange: 'phemex',
        isSnapshot: message.type === 'snapshot',
        bids: message.orderbook_p.bids.map(mapPerpBookLevel),
        asks: message.orderbook_p.asks.map(mapPerpBookLevel),
        timestamp: fromNanoSecondsToDate(message.timestamp),
        localTimestamp
      }
    }
  }
}

export class PhemexDerivativeTickerMapper implements Mapper<'phemex', DerivativeTicker> {
  private readonly pendingTickerInfoHelper = new PendingTickerInfoHelper()

  canHandle(message: PhemexTicker) {
    return 'market24h' in message || message.method === 'perp_market24h_pack_p.update'
  }

  getFilters(symbols?: string[]) {
    if (symbols == undefined || symbols.length === 0) {
      return [
        {
          channel: 'market24h'
        } as const,
        {
          channel: 'perp_market24h_pack_p'
        } as const
      ]
    }

    const { perpV2Symbols, otherSymbols } = getSymbols(symbols)
    const filters = []

    if (perpV2Symbols.length > 0) {
      filters.push({
        channel: 'perp_market24h_pack_p',
        symbols: perpV2Symbols
      } as const)
    }
    if (otherSymbols.length > 0) {
      filters.push({
        channel: 'market24h',
        symbols: otherSymbols
      } as const)
    }

    return filters
  }

  *map(message: PhemexTicker, localTimestamp: Date): IterableIterator<DerivativeTicker> {
    if ('market24h' in message) {
      const pendingTickerInfo = this.pendingTickerInfoHelper.getPendingTickerInfo(message.market24h.symbol, 'phemex')
      const phemexTicker = message.market24h
      pendingTickerInfo.updateFundingRate(phemexTicker.fundingRate / 100000000)
      pendingTickerInfo.updatePredictedFundingRate(phemexTicker.predFundingRate / 100000000)
      pendingTickerInfo.updateIndexPrice(phemexTicker.indexPrice / 10000)
      pendingTickerInfo.updateMarkPrice(phemexTicker.markPrice / 10000)
      pendingTickerInfo.updateOpenInterest(phemexTicker.openInterest)
      pendingTickerInfo.updateLastPrice(phemexTicker.close / 10000)
      pendingTickerInfo.updateTimestamp(fromNanoSecondsToDate(message.timestamp))

      if (pendingTickerInfo.hasChanged()) {
        yield pendingTickerInfo.getSnapshot(localTimestamp)
      }
    } else {
      for (let [
        symbol,
        _openRp,
        _highRp,
        _lowRp,
        lastRp,
        _volumeRq,
        _turnoverRv,
        openInterestRv,
        indexRp,
        markRp,
        fundingRateRr,
        predFundingRateRr
      ] of message.data) {
        const pendingTickerInfo = this.pendingTickerInfoHelper.getPendingTickerInfo(symbol, 'phemex')

        pendingTickerInfo.updateFundingRate(Number(fundingRateRr))
        pendingTickerInfo.updatePredictedFundingRate(Number(predFundingRateRr))
        pendingTickerInfo.updateIndexPrice(Number(indexRp))
        pendingTickerInfo.updateMarkPrice(Number(markRp))
        pendingTickerInfo.updateOpenInterest(Number(openInterestRv))
        pendingTickerInfo.updateLastPrice(Number(lastRp))
        pendingTickerInfo.updateTimestamp(fromNanoSecondsToDate(message.timestamp))

        if (pendingTickerInfo.hasChanged()) {
          yield pendingTickerInfo.getSnapshot(localTimestamp)
        }
      }
    }
  }
}

type PhemexTradeMessage =
  | {
      symbol: string
      trades: [[number, 'Buy' | 'Sell', number, number]]
      type: 'incremental' | 'snapshot'
    }
  | {
      sequence: 79157171
      symbol: 'BTCUSDT'
      trades_p: [[1669198793402790477, 'Buy' | 'Sell', '16545.6', '0.7']]
      type: 'snapshot' | 'incremental'
    }

type PhemexBookLevel = [number, number]

type PhemexBookMessage =
  | {
      book: {
        asks: PhemexBookLevel[]
        bids: PhemexBookLevel[]
      }

      symbol: string
      timestamp: number
      type: 'incremental' | 'snapshot'
    }
  | {
      depth: 0
      orderbook_p: {
        asks: [string, string][]
        bids: [string, string][]
      }
      sequence: 80321058
      symbol: 'BTCUSDT'
      timestamp: 1669198850490348246
      type: 'snapshot' | 'incremental'
    }

type PhemexTicker =
  | {
      market24h: {
        fundingRate: number
        indexPrice: number
        markPrice: number
        openInterest: number
        predFundingRate: number
        symbol: string
        close: number
      }

      timestamp: number
      method: undefined
    }
  | {
      data: [
        [
          'SOLUSDT',
          '11.246',
          '13.41',
          '10.91',
          '13.029',
          '10445.82',
          '127687.14224',
          '0',
          '13.03062296',
          '13.03154351',
          '0.0001',
          '0.0001'
        ],

        [
          'BTCUSDT',
          '15713.1',
          '16626',
          '15685.7',
          '16545.6',
          '1374.476',
          '22296790.4579',
          '0',
          '16553.56998432',
          '16554.73942506',
          '0.0001',
          '0.0001'
        ]
      ]
      method: 'perp_market24h_pack_p.update'
      timestamp: 1669198855202180601
      type: 'incremental'
    }