/**
 * Database Service for Trade Tracking and Analytics
 */

import { PrismaClient } from '@prisma/client'

// Singleton Prisma client
let prisma: PrismaClient | null = null

export function getPrismaClient(): PrismaClient {
  if (!prisma) {
    prisma = new PrismaClient({
      log: process.env.NODE_ENV === 'development' ? ['query', 'error', 'warn'] : ['error'],
    })
    console.log('✅ Prisma client initialized')
  }
  return prisma
}

export interface CreateTradeParams {
  positionId: string
  symbol: string
  direction: 'long' | 'short'
  entryPrice: number
  entrySlippage?: number
  positionSizeUSD: number
  leverage: number
  stopLossPrice: number
  softStopPrice?: number
  hardStopPrice?: number
  takeProfit1Price: number
  takeProfit2Price: number
  tp1SizePercent: number
  tp2SizePercent: number
  entryOrderTx: string
  tp1OrderTx?: string
  tp2OrderTx?: string
  slOrderTx?: string
  softStopOrderTx?: string
  hardStopOrderTx?: string
  configSnapshot: any
  signalSource?: string
  signalStrength?: string
  timeframe?: string
  isTestTrade?: boolean
  // Market context fields
  expectedEntryPrice?: number
  fundingRateAtEntry?: number
  atrAtEntry?: number
  adxAtEntry?: number
  rsiAtEntry?: number
  volumeAtEntry?: number
  pricePositionAtEntry?: number
  signalQualityScore?: number
}

export interface UpdateTradeStateParams {
  positionId: string
  currentSize: number
  tp1Hit: boolean
  slMovedToBreakeven: boolean
  slMovedToProfit: boolean
  stopLossPrice: number
  realizedPnL: number
  unrealizedPnL: number
  peakPnL: number
  lastPrice: number
  maxFavorableExcursion?: number
  maxAdverseExcursion?: number
  maxFavorablePrice?: number
  maxAdversePrice?: number
}

export interface UpdateTradeExitParams {
  positionId: string
  exitPrice: number
  exitReason: 'TP1' | 'TP2' | 'SL' | 'SOFT_SL' | 'HARD_SL' | 'manual' | 'emergency'
  realizedPnL: number
  exitOrderTx: string
  holdTimeSeconds: number
  maxDrawdown?: number
  maxGain?: number
  // MAE/MFE final values
  maxFavorableExcursion?: number
  maxAdverseExcursion?: number
  maxFavorablePrice?: number
  maxAdversePrice?: number
}

export async function createTrade(params: CreateTradeParams) {
  const prisma = getPrismaClient()
  
  try {
    // Calculate entry slippage if expected price provided
    let entrySlippagePct: number | undefined
    if (params.expectedEntryPrice && params.entrySlippage !== undefined) {
      entrySlippagePct = params.entrySlippage
    }
    
    const trade = await prisma.trade.create({
      data: {
        positionId: params.positionId,
        symbol: params.symbol,
        direction: params.direction,
        entryPrice: params.entryPrice,
        entryTime: new Date(),
        entrySlippage: params.entrySlippage,
        positionSizeUSD: params.positionSizeUSD,
        leverage: params.leverage,
        stopLossPrice: params.stopLossPrice,
        softStopPrice: params.softStopPrice,
        hardStopPrice: params.hardStopPrice,
        takeProfit1Price: params.takeProfit1Price,
        takeProfit2Price: params.takeProfit2Price,
        tp1SizePercent: params.tp1SizePercent,
        tp2SizePercent: params.tp2SizePercent,
        entryOrderTx: params.entryOrderTx,
        tp1OrderTx: params.tp1OrderTx,
        tp2OrderTx: params.tp2OrderTx,
        slOrderTx: params.slOrderTx,
        softStopOrderTx: params.softStopOrderTx,
        hardStopOrderTx: params.hardStopOrderTx,
        configSnapshot: params.configSnapshot,
        signalSource: params.signalSource,
        signalStrength: params.signalStrength,
        timeframe: params.timeframe,
        status: 'open',
        isTestTrade: params.isTestTrade || false,
        // Market context
        expectedEntryPrice: params.expectedEntryPrice,
        entrySlippagePct: entrySlippagePct,
        fundingRateAtEntry: params.fundingRateAtEntry,
        atrAtEntry: params.atrAtEntry,
        adxAtEntry: params.adxAtEntry,
        rsiAtEntry: params.rsiAtEntry,
        volumeAtEntry: params.volumeAtEntry,
        pricePositionAtEntry: params.pricePositionAtEntry,
        signalQualityScore: params.signalQualityScore,
      },
    })
    
    console.log(`📊 Trade record created: ${trade.id}`)
    return trade
  } catch (error) {
    console.error('❌ Failed to create trade record:', error)
    throw error
  }
}

/**
 * Update trade when position exits
 */
export async function updateTradeExit(params: UpdateTradeExitParams) {
  const prisma = getPrismaClient()
  
  try {
    // First fetch the trade to get positionSizeUSD
    const existingTrade = await prisma.trade.findUnique({
      where: { positionId: params.positionId },
      select: { positionSizeUSD: true },
    })
    
    if (!existingTrade) {
      throw new Error(`Trade not found: ${params.positionId}`)
    }
    
    const trade = await prisma.trade.update({
      where: { positionId: params.positionId },
      data: {
        exitPrice: params.exitPrice,
        exitTime: new Date(),
        exitReason: params.exitReason,
        realizedPnL: params.realizedPnL,
        realizedPnLPercent: (params.realizedPnL / existingTrade.positionSizeUSD) * 100,
        exitOrderTx: params.exitOrderTx,
        holdTimeSeconds: params.holdTimeSeconds,
        maxDrawdown: params.maxDrawdown,
        maxGain: params.maxGain,
        // Save final MAE/MFE values
        maxFavorableExcursion: params.maxFavorableExcursion,
        maxAdverseExcursion: params.maxAdverseExcursion,
        maxFavorablePrice: params.maxFavorablePrice,
        maxAdversePrice: params.maxAdversePrice,
        status: 'closed',
      },
    })
    
    console.log(`📊 Trade closed: ${trade.id} | P&L: $${params.realizedPnL.toFixed(2)}`)
    return trade
  } catch (error) {
    console.error('❌ Failed to update trade exit:', error)
    throw error
  }
}

/**
 * Update active trade state (for Position Manager persistence)
 */
export async function updateTradeState(params: UpdateTradeStateParams) {
  const prisma = getPrismaClient()
  
  try {
    const trade = await prisma.trade.update({
      where: { positionId: params.positionId },
      data: {
        // Store Position Manager state in configSnapshot
        configSnapshot: {
          ...(await prisma.trade.findUnique({ 
            where: { positionId: params.positionId },
            select: { configSnapshot: true }
          }))?.configSnapshot as any,
          // Add Position Manager state
          positionManagerState: {
            currentSize: params.currentSize,
            tp1Hit: params.tp1Hit,
            slMovedToBreakeven: params.slMovedToBreakeven,
            slMovedToProfit: params.slMovedToProfit,
            stopLossPrice: params.stopLossPrice,
            realizedPnL: params.realizedPnL,
            unrealizedPnL: params.unrealizedPnL,
            peakPnL: params.peakPnL,
            lastPrice: params.lastPrice,
            maxFavorableExcursion: params.maxFavorableExcursion,
            maxAdverseExcursion: params.maxAdverseExcursion,
            maxFavorablePrice: params.maxFavorablePrice,
            maxAdversePrice: params.maxAdversePrice,
            lastUpdate: new Date().toISOString(),
          }
        }
      },
    })
    
    return trade
  } catch (error) {
    console.error('❌ Failed to update trade state:', error)
    // Don't throw - state updates are non-critical
  }
}

/**
 * Get all open trades (for Position Manager recovery)
 */
export async function getOpenTrades() {
  const prisma = getPrismaClient()
  
  try {
    const trades = await prisma.trade.findMany({
      where: { status: 'open' },
      orderBy: { entryTime: 'asc' },
    })
    
    console.log(`📊 Found ${trades.length} open trades to restore`)
    return trades
  } catch (error) {
    console.error('❌ Failed to get open trades:', error)
    return []
  }
}

/**
 * Get the most recent trade entry time (for cooldown checking)
 */
export async function getLastTradeTime(): Promise<Date | null> {
  const prisma = getPrismaClient()
  
  try {
    const lastTrade = await prisma.trade.findFirst({
      orderBy: { entryTime: 'desc' },
      select: { entryTime: true },
    })
    
    return lastTrade?.entryTime || null
  } catch (error) {
    console.error('❌ Failed to get last trade time:', error)
    return null
  }
}

/**
 * Get the most recent trade time for a specific symbol
 */
export async function getLastTradeTimeForSymbol(symbol: string): Promise<Date | null> {
  const prisma = getPrismaClient()
  
  try {
    const lastTrade = await prisma.trade.findFirst({
      where: { symbol },
      orderBy: { entryTime: 'desc' },
      select: { entryTime: true },
    })
    
    return lastTrade?.entryTime || null
  } catch (error) {
    console.error(`❌ Failed to get last trade time for ${symbol}:`, error)
    return null
  }
}

/**
 * Get the most recent trade with full details
 */
export async function getLastTrade() {
  const prisma = getPrismaClient()
  
  try {
    const lastTrade = await prisma.trade.findFirst({
      orderBy: { createdAt: 'desc' },
    })
    
    return lastTrade
  } catch (error) {
    console.error('❌ Failed to get last trade:', error)
    return null
  }
}

/**
 * Get count of trades in the last hour
 */
export async function getTradesInLastHour(): Promise<number> {
  const prisma = getPrismaClient()
  
  try {
    const oneHourAgo = new Date(Date.now() - 60 * 60 * 1000)
    
    const count = await prisma.trade.count({
      where: {
        entryTime: {
          gte: oneHourAgo,
        },
      },
    })
    
    return count
  } catch (error) {
    console.error('❌ Failed to get trades in last hour:', error)
    return 0
  }
}

/**
 * Get total P&L for today
 */
export async function getTodayPnL(): Promise<number> {
  const prisma = getPrismaClient()
  
  try {
    const startOfDay = new Date()
    startOfDay.setHours(0, 0, 0, 0)
    
    const result = await prisma.trade.aggregate({
      where: {
        entryTime: {
          gte: startOfDay,
        },
        status: 'closed',
      },
      _sum: {
        realizedPnL: true,
      },
    })
    
    return result._sum.realizedPnL || 0
  } catch (error) {
    console.error('❌ Failed to get today PnL:', error)
    return 0
  }
}

/**
 * Add price update for a trade (for tracking max gain/drawdown)
 */
export async function addPriceUpdate(
  tradeId: string,
  price: number,
  pnl: number,
  pnlPercent: number
) {
  const prisma = getPrismaClient()
  
  try {
    await prisma.priceUpdate.create({
      data: {
        tradeId,
        price,
        pnl,
        pnlPercent,
      },
    })
  } catch (error) {
    console.error('❌ Failed to add price update:', error)
    // Don't throw - price updates are non-critical
  }
}

/**
 * Log system event
 */
export async function logSystemEvent(
  eventType: string,
  message: string,
  details?: any
) {
  const prisma = getPrismaClient()
  
  try {
    await prisma.systemEvent.create({
      data: {
        eventType,
        message,
        details: details ? JSON.parse(JSON.stringify(details)) : null,
      },
    })
  } catch (error) {
    console.error('❌ Failed to log system event:', error)
  }
}

/**
 * Get trade statistics
 */
export async function getTradeStats(days: number = 30) {
  const prisma = getPrismaClient()
  
  const since = new Date()
  since.setDate(since.getDate() - days)
  
  const trades = await prisma.trade.findMany({
    where: {
      createdAt: { gte: since },
      status: 'closed',
      isTestTrade: false, // Exclude test trades from stats
    },
  })
  
  const winning = trades.filter((t) => (t.realizedPnL ?? 0) > 0)
  const losing = trades.filter((t) => (t.realizedPnL ?? 0) < 0)
  
  const totalPnL = trades.reduce((sum, t) => sum + (t.realizedPnL ?? 0), 0)
  const winRate = trades.length > 0 ? (winning.length / trades.length) * 100 : 0
  
  const avgWin = winning.length > 0
    ? winning.reduce((sum, t) => sum + (t.realizedPnL ?? 0), 0) / winning.length
    : 0
    
  const avgLoss = losing.length > 0
    ? losing.reduce((sum, t) => sum + (t.realizedPnL ?? 0), 0) / losing.length
    : 0
  
  return {
    totalTrades: trades.length,
    winningTrades: winning.length,
    losingTrades: losing.length,
    winRate: winRate.toFixed(2),
    totalPnL: totalPnL.toFixed(2),
    avgWin: avgWin.toFixed(2),
    avgLoss: avgLoss.toFixed(2),
    profitFactor: avgLoss !== 0 ? (avgWin / Math.abs(avgLoss)).toFixed(2) : 'N/A',
  }
}

/**
 * Disconnect Prisma client (for graceful shutdown)
 */
export async function disconnectPrisma() {
  if (prisma) {
    await prisma.$disconnect()
    prisma = null
    console.log('✅ Prisma client disconnected')
  }
}