/**
 * Signal Quality Scoring
 * 
 * Unified quality scoring logic used by both check-risk and execute endpoints.
 * Ensures consistent scoring across the trading pipeline.
 */

import { getRecentSignals } from '../database/trades'
import { logger } from '../utils/logger'

export interface SignalQualityResult {
  score: number
  passed: boolean
  reasons: string[]
  frequencyPenalties?: {
    overtrading: number
    flipFlop: number
    alternating: number
  }
}

/**
 * Calculate signal quality score based on technical indicators
 * 
 * Scoring breakdown:
 * - Base: 50 points
 * - ATR (volatility): -20 to +10 points
 * - ADX (trend strength): -15 to +15 points
 * - RSI (momentum): -10 to +10 points
 * - Volume: -10 to +15 points
 * - Price position: -15 to +5 points
 * - Volume breakout bonus: +10 points
 * - Signal frequency penalties: -20 to -30 points
 * 
 * Total range: ~15-115 points (realistically 30-100)
 * Threshold: 60 points minimum for execution
 * 
 * TIMEFRAME-AWARE SCORING:
 * - 5min charts have lower ADX/ATR thresholds (trends develop slower)
 * - Higher timeframes require stronger confirmation
 * 
 * SIGNAL FREQUENCY PENALTIES (NEW):
 * - 3+ signals in 30 min: -20 points (overtrading zone)
 * - Opposite direction in last 15 min: -25 points (flip-flop)
 * - Last 3 trades alternating: -30 points (chop pattern)
 */
export async function scoreSignalQuality(params: {
  atr: number
  adx: number
  rsi: number
  volumeRatio: number
  pricePosition: number
  direction: 'long' | 'short'
  symbol: string // Required for frequency check
  currentPrice?: number // Required for flip-flop price context check
  timeframe?: string // "5" = 5min, "15" = 15min, "60" = 1H, "D" = daily
  minScore?: number // Configurable minimum score threshold
  skipFrequencyCheck?: boolean // For testing or when frequency check not needed
  maGap?: number // V9: MA gap percentage (MA50-MA200)/MA200*100
}): Promise<SignalQualityResult> {
  let score = 50 // Base score
  const reasons: string[] = []

  // Determine if this is a short timeframe (5min, 15min)
  const is5minChart = params.timeframe === '5'
  const is15minChart = params.timeframe === '15'
  const isShortTimeframe = is5minChart || is15minChart

  // ATR check (volatility gate: 0.15% - 2.5%)
  if (params.atr > 0) {
    if (params.atr < 0.15) {
      score -= 15
      reasons.push(`ATR too low (${params.atr.toFixed(2)}% - dead market)`)
    } else if (params.atr > 2.5) {
      score -= 20
      reasons.push(`ATR too high (${params.atr.toFixed(2)}% - too volatile)`)
    } else if (params.atr >= 0.15 && params.atr < 0.4) {
      score += 5
      reasons.push(`ATR moderate (${params.atr.toFixed(2)}%)`)
    } else {
      score += 10
      reasons.push(`ATR healthy (${params.atr.toFixed(2)}%)`)
    }
  }

  // ADX check - TIMEFRAME AWARE (trend strength)
  // 5min/15min: 12-22 is healthy (trends develop slower)
  // 1H+: 18+ is healthy (stronger trends expected)
  if (params.adx > 0) {
    if (isShortTimeframe) {
      // 5min/15min thresholds
      if (params.adx > 22) {
        score += 15
        reasons.push(`Strong trend for ${params.timeframe}min (ADX ${params.adx.toFixed(1)})`)
      } else if (params.adx < 12) {
        score -= 15
        reasons.push(`Weak trend for ${params.timeframe}min (ADX ${params.adx.toFixed(1)})`)
      } else {
        score += 5
        reasons.push(`Moderate trend for ${params.timeframe}min (ADX ${params.adx.toFixed(1)})`)
      }
    } else {
      // Higher timeframe thresholds (1H, 4H, D)
      if (params.adx > 25) {
        score += 15
        reasons.push(`Strong trend (ADX ${params.adx.toFixed(1)})`)
      } else if (params.adx < 18) {
        score -= 15
        reasons.push(`Weak trend (ADX ${params.adx.toFixed(1)})`)
      } else {
        score += 5
        reasons.push(`Moderate trend (ADX ${params.adx.toFixed(1)})`)
      }
    }
  }

  // RSI check (momentum confirmation)
  if (params.rsi > 0) {
    if (params.direction === 'long') {
      if (params.rsi > 50 && params.rsi < 70) {
        score += 10
        reasons.push(`RSI supports long (${params.rsi.toFixed(1)})`)
      } else if (params.rsi > 70) {
        score -= 10
        reasons.push(`RSI overbought (${params.rsi.toFixed(1)})`)
      }
    } else { // short
      // v10 (Nov 26, 2025): RSI is NOT a good SHORT filter!
      // Data analysis of 95 SHORTs showed:
      //   - Winning SHORTs: avg RSI 45.8 (HIGHER than losers!)
      //   - Losing SHORTs: avg RSI 42.9
      //   - RSI 50+: 68.2% WR, +$29.88 profit (BEST performance)
      // RSI alone is counterintuitive for shorts - focus on ADX + price position instead
      
      // Give small bonus for typical short RSI range, but don't penalize high RSI
      if (params.rsi < 50 && params.rsi > 30) {
        score += 5
        reasons.push(`RSI supports short (${params.rsi.toFixed(1)})`)
      } else if (params.rsi < 30) {
        score -= 10
        reasons.push(`RSI oversold - bounce risk (${params.rsi.toFixed(1)})`)
      }
      // No penalty for RSI 50+ - data shows these are actually the best shorts!
    }
  }

  // Volume check (want > 1.0 = above average)
  // ANTI-CHOP FILTER: High volume + low ADX = whipsaw trap
  if (params.volumeRatio > 0) {
    const isChoppy = params.adx > 0 && params.adx < 16
    const hasHighVolume = params.volumeRatio > 1.5
    
    if (isChoppy && hasHighVolume) {
      // High volume during choppy conditions (ADX < 16) is often a trap
      score -= 15
      reasons.push(`⚠️ Whipsaw trap: High volume (${params.volumeRatio.toFixed(2)}x) + choppy market (ADX ${params.adx.toFixed(1)})`)
    } else if (params.volumeRatio > 1.5) {
      score += 15
      reasons.push(`Very strong volume (${params.volumeRatio.toFixed(2)}x avg)`)
    } else if (params.volumeRatio > 1.2) {
      score += 10
      reasons.push(`Strong volume (${params.volumeRatio.toFixed(2)}x avg)`)
    } else if (params.volumeRatio < 0.8) {
      score -= 10
      reasons.push(`Weak volume (${params.volumeRatio.toFixed(2)}x avg)`)
    }
  }

  // Price position check (avoid chasing vs breakout detection)
  if (params.pricePosition > 0) {
    if (params.direction === 'long' && params.pricePosition > 95) {
      // High volume breakout at range top can be good
      if (params.volumeRatio > 1.4) {
        score += 5
        reasons.push(`Volume breakout at range top (${params.pricePosition.toFixed(0)}%, vol ${params.volumeRatio.toFixed(2)}x)`)
      } else {
        score -= 15
        reasons.push(`Price near top of range (${params.pricePosition.toFixed(0)}%) - risky long`)
      }
    } else if (params.direction === 'short' && params.pricePosition < 5) {
      // High volume breakdown at range bottom can be good
      if (params.volumeRatio > 1.4) {
        score += 5
        reasons.push(`Volume breakdown at range bottom (${params.pricePosition.toFixed(0)}%, vol ${params.volumeRatio.toFixed(2)}x)`)
      } else {
        score -= 15
        reasons.push(`Price near bottom of range (${params.pricePosition.toFixed(0)}%) - risky short`)
      }
    } else {
      score += 5
      reasons.push(`Price position OK (${params.pricePosition.toFixed(0)}%)`)
    }
  }

  // Volume breakout bonus (high volume can override other weaknesses)
  if (params.volumeRatio > 1.8 && params.atr < 0.6) {
    score += 10
    reasons.push(`Volume breakout compensates for low ATR`)
  }

  // Signal frequency penalties (check database for recent signals)
  const frequencyPenalties = {
    overtrading: 0,
    flipFlop: 0,
    alternating: 0,
  }

  if (!params.skipFrequencyCheck) {
    try {
      const recentSignals = await getRecentSignals({
        symbol: params.symbol,
        direction: params.direction,
        timeWindowMinutes: 30,
        timeframe: params.timeframe,
      })

      // Penalty 1: Overtrading (3+ signals in 30 minutes)
      if (recentSignals.totalSignals >= 3) {
        frequencyPenalties.overtrading = -20
        score -= 20
        reasons.push(`⚠️ Overtrading zone: ${recentSignals.totalSignals} signals in 30min (-20 pts)`)
      }

      // Penalty 2: Flip-flop (opposite direction in last 15 minutes)
      // BUT: Only penalize if price hasn't moved significantly (< 2% from opposite signal)
      // This distinguishes chop (bad) from legitimate reversals (good)
      if (recentSignals.oppositeDirectionInWindow && recentSignals.oppositeDirectionPrice) {
        if (!params.currentPrice || params.currentPrice === 0) {
          // No current price available - apply penalty (conservative)
          console.warn(`⚠️ Flip-flop check: No currentPrice available, applying penalty`)
          frequencyPenalties.flipFlop = -25
          score -= 25
          reasons.push(`⚠️ Flip-flop detected: opposite direction ${recentSignals.oppositeDirectionMinutesAgo}min ago, no price data (-25 pts)`)
        } else {
          const priceChangePercent = Math.abs(
            (params.currentPrice - recentSignals.oppositeDirectionPrice) / recentSignals.oppositeDirectionPrice * 100
          )
          
          logger.log(`🔍 Flip-flop price check: $${recentSignals.oppositeDirectionPrice.toFixed(2)} → $${params.currentPrice.toFixed(2)} = ${priceChangePercent.toFixed(2)}%`)
          
          if (priceChangePercent < 2.0) {
            // Small price move = consolidation/chop = BAD
            frequencyPenalties.flipFlop = -25
            score -= 25
            reasons.push(
              `⚠️ Flip-flop in tight range: ${recentSignals.oppositeDirectionMinutesAgo}min ago, ` +
              `only ${priceChangePercent.toFixed(2)}% move ($${recentSignals.oppositeDirectionPrice.toFixed(2)} → $${params.currentPrice.toFixed(2)}) (-25 pts)`
            )
          } else {
            // Large price move = potential reversal = ALLOW
            reasons.push(
              `✅ Direction change after ${priceChangePercent.toFixed(1)}% move ` +
              `($${recentSignals.oppositeDirectionPrice.toFixed(2)} → $${params.currentPrice.toFixed(2)}, ${recentSignals.oppositeDirectionMinutesAgo}min ago) - reversal allowed`
            )
          }
        }
      } else if (recentSignals.oppositeDirectionInWindow && !recentSignals.oppositeDirectionPrice) {
        // Fallback: If we don't have opposite price data, apply penalty (conservative)
        frequencyPenalties.flipFlop = -25
        score -= 25
        reasons.push(`⚠️ Flip-flop detected: opposite direction ${recentSignals.oppositeDirectionMinutesAgo}min ago, no historical price (-25 pts)`)
      }

      // Penalty 3: Alternating pattern (last 3 trades flip directions)
      if (recentSignals.isAlternatingPattern) {
        frequencyPenalties.alternating = -30
        score -= 30
        const pattern = recentSignals.last3Trades.map(t => t.direction).join(' → ')
        reasons.push(`⚠️ Chop pattern: last 3 trades alternating (${pattern}) (-30 pts)`)
      }
    } catch (error) {
      // Don't fail the whole score if frequency check fails
      console.error('❌ Signal frequency check failed:', error)
      reasons.push('⚠️ Frequency check unavailable (no penalty applied)')
    }
  }

  // V9: MA Gap Analysis (Nov 26, 2025)
  // MA convergence/divergence indicates momentum building or fading
  // Helps catch early trend signals when MAs align with direction
  if (params.maGap !== undefined && params.maGap !== null) {
    if (params.direction === 'long') {
      if (params.maGap >= 0 && params.maGap < 2.0) {
        // Tight bullish convergence (MA50 above MA200, close together)
        score += 15
        reasons.push(`✅ Tight bullish MA convergence (${params.maGap.toFixed(2)}% gap) (+15 pts)`)
      } else if (params.maGap < 0 && params.maGap > -2.0) {
        // MAs converging from below (MA50 approaching MA200)
        score += 12
        reasons.push(`✅ MAs converging bullish (${params.maGap.toFixed(2)}% gap) (+12 pts)`)
      } else if (params.maGap < -2.0 && params.maGap > -5.0) {
        // Early momentum building
        score += 8
        reasons.push(`✅ Early bullish momentum (${params.maGap.toFixed(2)}% gap) (+8 pts)`)
      } else if (params.maGap >= 2.0) {
        // Wide gap = momentum already extended
        score += 5
        reasons.push(`⚠️ Extended bullish gap (${params.maGap.toFixed(2)}%) (+5 pts)`)
      } else if (params.maGap <= -5.0) {
        // Very bearish MA structure for long
        score -= 5
        reasons.push(`⚠️ Bearish MA structure for long (${params.maGap.toFixed(2)}%) (-5 pts)`)
      }
    } else if (params.direction === 'short') {
      if (params.maGap <= 0 && params.maGap > -2.0) {
        // Tight bearish convergence (MA50 below MA200, close together)
        score += 15
        reasons.push(`✅ Tight bearish MA convergence (${params.maGap.toFixed(2)}% gap) (+15 pts)`)
      } else if (params.maGap > 0 && params.maGap < 2.0) {
        // MAs converging from above (MA50 approaching MA200)
        score += 12
        reasons.push(`✅ MAs converging bearish (${params.maGap.toFixed(2)}% gap) (+12 pts)`)
      } else if (params.maGap > 2.0 && params.maGap < 5.0) {
        // Early momentum building
        score += 8
        reasons.push(`✅ Early bearish momentum (${params.maGap.toFixed(2)}% gap) (+8 pts)`)
      } else if (params.maGap <= -2.0) {
        // Wide gap = momentum already extended
        score += 5
        reasons.push(`⚠️ Extended bearish gap (${params.maGap.toFixed(2)}%) (+5 pts)`)
      } else if (params.maGap >= 5.0) {
        // Very bullish MA structure for short
        score -= 5
        reasons.push(`⚠️ Bullish MA structure for short (${params.maGap.toFixed(2)}%) (-5 pts)`)
      }
    }
  }

  // Direction-specific threshold support (Nov 23, 2025)
  // Use provided minScore, or fall back to 60 if not specified
  const minScore = params.minScore || 60
  const passed = score >= minScore

  return {
    score,
    passed,
    reasons,
    frequencyPenalties,
  }
}