/**
 * FlowState AI Agent Engine — Autonomous churn detection & retention
 * 5-signal scoring: inactivity, volume decline, protocol diversity, streak, liquidation
 * Supports configurable thresholds and pre-churn early warning detection.
 */
import { ChurnRisk } from './types'
import { sendCustomEvent } from './torque-mcp'

export interface ScoringThresholds {
  inactivityCritical: number   // days inactive → critical signal (default 30)
  inactivityHigh: number       // days inactive → high signal (default 14)
  inactivityMedium: number     // days inactive → medium signal (default 7)
  volumeDropCritical: number   // % volume drop → critical signal (default 80)
  volumeDropHigh: number       // % volume drop → high signal (default 50)
  volumeDropMedium: number     // % volume drop → medium signal (default 25)
  preChurnDaysTrader: number   // days quiet for trader type (default 3)
  preChurnDaysLP: number       // days quiet for LP type (default 5)
  preChurnDaysStaker: number   // days quiet for staker type (default 7)
}

export const DEFAULT_THRESHOLDS: ScoringThresholds = {
  inactivityCritical: 30,
  inactivityHigh: 14,
  inactivityMedium: 7,
  volumeDropCritical: 80,
  volumeDropHigh: 50,
  volumeDropMedium: 25,
  preChurnDaysTrader: 3,
  preChurnDaysLP: 5,
  preChurnDaysStaker: 7,
}

export type WalletType = 'trader' | 'lp' | 'staker'

const TRADER_PROTOCOLS = new Set(['Jupiter', 'Raydium', 'Drift', 'Tensor'])
const LP_PROTOCOLS = new Set(['Kamino', 'Marginfi', 'Meteora'])

export function classifyWalletType(protocols: string[]): WalletType {
  const traderCount = protocols.filter(p => TRADER_PROTOCOLS.has(p)).length
  const lpCount = protocols.filter(p => LP_PROTOCOLS.has(p)).length
  if (traderCount >= 2) return 'trader'
  if (lpCount >= 1) return 'lp'
  return 'staker'
}

export function detectPreChurn(
  daysInactive: number,
  streak: number,
  protocols: string[],
  thresholds: ScoringThresholds = DEFAULT_THRESHOLDS
): { isPreChurn: boolean; walletType: WalletType; threshold: number } {
  const walletType = classifyWalletType(protocols)
  const threshold =
    walletType === 'trader'
      ? thresholds.preChurnDaysTrader
      : walletType === 'lp'
        ? thresholds.preChurnDaysLP
        : thresholds.preChurnDaysStaker
  // Pre-churn: below inactivity medium threshold but streak recently broken
  const isPreChurn =
    daysInactive >= threshold &&
    daysInactive < thresholds.inactivityMedium &&
    streak <= 2
  return { isPreChurn, walletType, threshold }
}

export function calculateChurnScore(
  activity: {
    daysInactive: number; volumeDropPct: number; uniqueProtocols: number;
    currentStreak: number; hasLiquidation: boolean
  },
  thresholds: ScoringThresholds = DEFAULT_THRESHOLDS
): { score: number; risk: ChurnRisk; signals: string[] } {
  let score = 0
  const signals: string[] = []

  // Signal 1: Inactivity (0-30pts)
  const inactScore = Math.min(activity.daysInactive * 3, 30)
  score += inactScore
  if (activity.daysInactive >= thresholds.inactivityMedium) {
    signals.push('Inactive ' + activity.daysInactive + ' days')
  }

  // Signal 2: Volume decline (0-25pts)
  if (activity.volumeDropPct > 0) {
    score += Math.min(activity.volumeDropPct / 4, 25)
    if (activity.volumeDropPct >= thresholds.volumeDropMedium) {
      signals.push('Volume dropped ' + activity.volumeDropPct.toFixed(0) + '%')
    }
  }

  // Signal 3: Protocol diversity (0-15pts)
  if (activity.uniqueProtocols <= 1) { score += 15; signals.push('Single protocol — low engagement') }
  else if (activity.uniqueProtocols <= 2) { score += 8; signals.push('Limited protocol diversity') }

  // Signal 4: Streak broken (0-15pts)
  if (activity.currentStreak === 0) { score += 15; signals.push('Activity streak broken') }
  else if (activity.currentStreak < 3) score += 5

  // Signal 5: Liquidation (0-15pts)
  if (activity.hasLiquidation) { score += 15; signals.push('Recent liquidation event') }

  score = Math.min(Math.max(score, 0), 100)

  let risk: ChurnRisk
  if (score >= 80) risk = 'critical'
  else if (score >= 60) risk = 'high'
  else if (score >= 40) risk = 'medium'
  else if (score >= 20) risk = 'low'
  else risk = 'safe'

  return { score, risk, signals }
}

export function selectResponse(risk: ChurnRisk, wallet: string): { action: string; description: string }[] {
  const responses: { action: string; description: string }[] = []
  responses.push({ action: 'detect', description: 'Detected ' + risk + ' churn risk for ' + wallet.slice(0, 8) + '...' })

  switch (risk) {
    case 'critical':
      responses.push({ action: 'gift', description: 'Sending 0.5 SOL gift via Anti-Churn campaign' })
      responses.push({ action: 'raffle', description: 'Enrolling in Comeback Raffle with 5x multiplier' })
      break
    case 'high':
      responses.push({ action: 'raffle', description: 'Enrolling in Comeback Raffle with 3x multiplier' })
      break
    case 'medium':
      responses.push({ action: 'rebate', description: 'Activating 2x rebate boost for 48 hours' })
      break
  }
  return responses
}

export async function executeResponse(wallet: string, action: string) {
  const eventName =
    action === 'gift' || action === 'raffle' ? 'churn_risk_high'
    : action === 'rebate' ? 'churn_risk_medium'
    : 'inactivity_detected'
  return sendCustomEvent(wallet, eventName, { triggeredAction: action, detectedBy: 'flowstate-ai-agent', timestamp: new Date().toISOString() })
}