// Computed achievements derived from bot stats + fight history
// No schema changes — achievements are calculated on the fly

export interface Achievement {
  id: string
  name: string
  description: string
  icon: string
}

interface BotStats {
  wins: number
  losses: number
  winStreak: number
  bestStreak: number
  tier: number
  eloRating: number
}

interface FightRecord {
  winnerId: string | null
  totalRounds: number
  botAHp: number
  botBHp: number
  botAId: string
  botBId: string
}

export function computeAchievements(botId: string, stats: BotStats, fights: FightRecord[]): Achievement[] {
  const earned: Achievement[] = []
  const total = stats.wins + stats.losses

  // Win milestones
  if (stats.wins >= 1) earned.push({ id: 'first_blood', name: 'First Blood', description: 'Win your first fight', icon: '🩸' })
  if (stats.wins >= 10) earned.push({ id: 'veteran', name: 'Veteran', description: 'Win 10 fights', icon: '⚔️' })
  if (stats.wins >= 50) earned.push({ id: 'warlord', name: 'Warlord', description: 'Win 50 fights', icon: '👑' })
  if (stats.wins >= 100) earned.push({ id: 'centurion', name: 'Centurion', description: 'Win 100 fights', icon: '🏛️' })

  // Streak achievements
  if (stats.bestStreak >= 3) earned.push({ id: 'hot_streak', name: 'Hot Streak', description: 'Win 3 fights in a row', icon: '🔥' })
  if (stats.bestStreak >= 5) earned.push({ id: 'unstoppable', name: 'Unstoppable', description: 'Win 5 fights in a row', icon: '💪' })
  if (stats.bestStreak >= 10) earned.push({ id: 'juggernaut', name: 'Juggernaut', description: 'Win 10 fights in a row', icon: '🚂' })

  // Tier achievements
  if (stats.tier >= 2) earned.push({ id: 'silver', name: 'Silver League', description: 'Reach Silver tier', icon: '🥈' })
  if (stats.tier >= 4) earned.push({ id: 'platinum', name: 'Platinum League', description: 'Reach Platinum tier', icon: '💎' })
  if (stats.tier >= 6) earned.push({ id: 'legend', name: 'Legend', description: 'Reach Legend tier', icon: '🌟' })

  // ELO achievements
  if (stats.eloRating >= 1500) earned.push({ id: 'elite', name: 'Elite', description: 'Reach 1500 ELO', icon: '📈' })
  if (stats.eloRating >= 2000) earned.push({ id: 'grandmaster', name: 'Grandmaster', description: 'Reach 2000 ELO', icon: '🏆' })

  // Fight-history based achievements
  const perfectWins = fights.filter(f => {
    if (f.winnerId !== botId) return false
    const isA = f.botAId === botId
    const loserHp = isA ? f.botBHp : f.botAHp
    return loserHp <= 0
  }).length

  if (perfectWins >= 1) earned.push({ id: 'perfect', name: 'Flawless', description: 'Win with a perfect finish', icon: '✨' })
  if (perfectWins >= 5) earned.push({ id: 'perfect_5', name: 'Perfectionist', description: 'Get 5 perfect finishes', icon: '💯' })

  const koWins = fights.filter(f => {
    if (f.winnerId !== botId) return false
    return f.totalRounds < 10
  }).length

  if (koWins >= 1) earned.push({ id: 'ko', name: 'Knockout Artist', description: 'Win by KO', icon: '💥' })
  if (koWins >= 10) earned.push({ id: 'ko_10', name: 'One-Punch Bot', description: 'Get 10 KO wins', icon: '🥊' })

  // Resilience
  if (stats.losses >= 10 && stats.wins > stats.losses) earned.push({ id: 'comeback_kid', name: 'Comeback Kid', description: 'Win more than you lose after 10+ losses', icon: '🐛' })

  // Activity
  if (total >= 50) earned.push({ id: 'grinder', name: 'Grinder', description: 'Fight 50 total battles', icon: '⚙️' })
  if (total >= 100) earned.push({ id: 'gladiator', name: 'Gladiator', description: 'Fight 100 total battles', icon: '🗡️' })

  return earned
}