// Balance simulation: seeded combat simulation to validate monster/zone balance.
// Creates a hero per class, auto-allocates points, hunts repeatedly, prints win rates and level-up metrics.
// Usage: node scripts/sim-balance.js
//
// 10.18: Monster stats must match src/db/migrations/008_balance.sql

const { mulberry32, rngInt } = require('../src/utils/rng');
const { calcDerived } = require('../src/game/stats');
const { resolveCombat } = require('../src/game/combat');
const { calculateRewards, rollLoot } = require('../src/game/rewards');
const { applyXpGain, xpToNext } = require('../src/game/leveling');
const { getClass, getBaseStats, CLASS_KEYS } = require('../src/game/classes');
const { getEquipmentBonuses } = require('../src/game/equipment');

// ─── Seeded RNG ────────────────────────────────────────────────────────────
var SEED = 42;

// ─── Zone / monster definitions (MUST match 008_balance.sql) ────────────────
var ZONES = {
  meadows: { slug: 'whispering-meadows', minLevel: 1, energyCost: 5, monsters: [
    { name: 'Giant Rat', level: 1, hp: 200, attack: 6, defense: 8, speed: 12, xp: 50, goldMin: 3, goldMax: 7 },
    { name: 'Meadow Wolf', level: 2, hp: 250, attack: 8, defense: 8, speed: 16, xp: 65, goldMin: 5, goldMax: 12 },
    { name: 'Goblin Scrapper', level: 3, hp: 300, attack: 10, defense: 8, speed: 11, xp: 85, goldMin: 8, goldMax: 18 },
  ]},
  forest: { slug: 'gloomroot-forest', minLevel: 5, energyCost: 8, monsters: [
    { name: 'Webspinner', level: 5, hp: 200, attack: 25, defense: 30, speed: 15, xp: 90, goldMin: 12, goldMax: 24 },
    { name: 'Bandit Cutthroat', level: 6, hp: 250, attack: 30, defense: 30, speed: 14, xp: 120, goldMin: 18, goldMax: 36 },
    { name: 'Mossback Treant', level: 8, hp: 320, attack: 35, defense: 30, speed: 7, xp: 160, goldMin: 22, goldMax: 44 },
  ]},
  crags: { slug: 'ashfang-crag', minLevel: 10, energyCost: 12, monsters: [
    { name: 'Ember Imp', level: 10, hp: 150, attack: 25, defense: 12, speed: 20, xp: 200, goldMin: 30, goldMax: 55 },
    { name: 'Stone Golem', level: 12, hp: 300, attack: 30, defense: 12, speed: 5, xp: 280, goldMin: 40, goldMax: 75 },
    { name: 'Ashfang Drake', level: 14, hp: 400, attack: 28, defense: 3, speed: 18, xp: 350, goldMin: 55, goldMax: 110 },
  ]},
};

var MONSTER_WEIGHTS = { meadows: [30, 20, 15], forest: [25, 20, 10], crags: [25, 10, 5] };

// ─── Simulation helpers ────────────────────────────────────────────────────

function pickMonster(zoneKey, rng) {
  var zone = ZONES[zoneKey];
  var weights = MONSTER_WEIGHTS[zoneKey];
  var total = weights.reduce(function(a, b) { return a + b; }, 0);
  var r = rng() * total;
  for (var i = 0; i < zone.monsters.length; i++) {
    r -= weights[i];
    if (r < 0) return zone.monsters[i];
  }
  return zone.monsters[zone.monsters.length - 1];
}

function simulateHunt(hero, monster, rng) {
  var equipBonuses = { bonus_str: 0, bonus_agi: 0, bonus_int: 0, bonus_vit: 0, bonus_attack: 0, bonus_defense: 0 };
  var fight = resolveCombat({
    class: hero.class, level: hero.level, hpCurrent: hero.hp,
    str: hero.str, agi: hero.agi, int: hero.int, vit: hero.vit,
    bonus_str: 0, bonus_agi: 0, bonus_int: 0, bonus_vit: 0, bonus_attack: 0, bonus_defense: 0,
  }, monster, rng);

  var xpGained = 0, goldGained = 0;
  if (fight.winner === 'hero') {
    var rewards = calculateRewards(monster.xp, monster.goldMin, monster.goldMax, monster.level, hero.level, rng);
    xpGained = rewards.xp;
    goldGained = rewards.gold;
  }

  return { winner: fight.winner, hpRemaining: fight.hpRemaining, xpGained: xpGained, goldGained: goldGained };
}

// ─── Run simulation for one class ──────────────────────────────────────────

function simulateClass(className) {
  var cls = getClass(className);
  var base = getBaseStats(className);
  var rng = mulberry32(SEED + CLASS_KEYS.indexOf(className));

  var hero = {
    class: className, level: 1, xp: 0, totalXpForLevel: 0, hp: 0, maxHp: 0,
    str: base.str, agi: base.agi, int: base.int, vit: base.vit,
    gold: 50,
  };

  var derived = calcDerived({ str: hero.str, agi: hero.agi, int: hero.int, vit: hero.vit }, hero.level, className);
  hero.hp = derived.maxHp;
  hero.maxHp = derived.maxHp;

  var results = { meadows: { wins: 0, total: 0 }, forest: { wins: 0, total: 0 }, crags: { wins: 0, total: 0 } };
  var totalHunts = 0;
  var consecutiveDefeats = 0;
  var MAX_DEFEATS = 200; // increased from 50 — low-vit classes need more attempts

  // Phase 1: Level 1 → 5 in Meadows
  while (hero.level < 5 && consecutiveDefeats < MAX_DEFEATS) {
    var monster = pickMonster('meadows', rng);
    var result = simulateHunt(hero, monster, rng);
    results.meadows.total++;
    if (result.winner === 'hero') {
      results.meadows.wins++;
      consecutiveDefeats = 0;
      var xpResult = applyXpGain(hero.level, hero.xp, 0, result.xpGained);
      if (xpResult.level > hero.level) {
        var newDerived = calcDerived({ str: hero.str, agi: hero.agi, int: hero.int, vit: hero.vit }, xpResult.level, className);
        hero.hp = newDerived.maxHp;
        hero.maxHp = newDerived.maxHp;
      }
      hero.xp = xpResult.xp;
      hero.level = xpResult.level;
      hero.gold += result.goldGained;
      hero.hp = Math.min(hero.maxHp, hero.hp + Math.floor(hero.maxHp * 0.1));
    } else {
      hero.hp = 1;
      hero.gold = Math.max(0, hero.gold - Math.floor(hero.gold * 0.1));
      consecutiveDefeats++;
    }
    totalHunts++;
  }

  var huntsL1to5 = totalHunts;

  // Phase 2: Level 5 → 10 in Forest
  while (hero.level < 10 && consecutiveDefeats < MAX_DEFEATS) {
    var monster = pickMonster('forest', rng);
    var result = simulateHunt(hero, monster, rng);
    results.forest.total++;
    if (result.winner === 'hero') {
      results.forest.wins++;
      consecutiveDefeats = 0;
      var xpResult = applyXpGain(hero.level, hero.xp, 0, result.xpGained);
      if (xpResult.level > hero.level) {
        var newDerived = calcDerived({ str: hero.str, agi: hero.agi, int: hero.int, vit: hero.vit }, xpResult.level, className);
        hero.hp = newDerived.maxHp;
        hero.maxHp = newDerived.maxHp;
      }
      hero.xp = xpResult.xp;
      hero.level = xpResult.level;
      hero.gold += result.goldGained;
      hero.hp = Math.min(hero.maxHp, hero.hp + Math.floor(hero.maxHp * 0.1));
    } else {
      hero.hp = 1;
      hero.gold = Math.max(0, hero.gold - Math.floor(hero.gold * 0.1));
      consecutiveDefeats++;
    }
    totalHunts++;
  }

  var huntsL1to10 = totalHunts;

  // Phase 3: Level 10+ in Crags (run until max level or 300 hunts)
  var cragsHunts = 0;
  while (cragsHunts < 300) {
    var monster = pickMonster('crags', rng);
    var result = simulateHunt(hero, monster, rng);
    results.crags.total++;
    if (result.winner === 'hero') {
      results.crags.wins++;
      consecutiveDefeats = 0;
      var xpResult = applyXpGain(hero.level, hero.xp, 0, result.xpGained);
      if (xpResult.level > hero.level) {
        var newDerived = calcDerived({ str: hero.str, agi: hero.agi, int: hero.int, vit: hero.vit }, xpResult.level, className);
        hero.hp = newDerived.maxHp;
        hero.maxHp = newDerived.maxHp;
      }
      hero.xp = xpResult.xp;
      hero.level = xpResult.level;
      hero.gold += result.goldGained;
      hero.hp = Math.min(hero.maxHp, hero.hp + Math.floor(hero.maxHp * 0.1));
    } else {
      hero.hp = 1;
      hero.gold = Math.max(0, hero.gold - Math.floor(hero.gold * 0.1));
      consecutiveDefeats++;
    }
    cragsHunts++;
    totalHunts++;
  }

  return { className: className, cls: cls, results: results, huntsL1to5: huntsL1to5, huntsL1to10: huntsL1to10, finalLevel: hero.level, finalGold: hero.gold };
}

// ─── Level-1 zone win rates ────────────────────────────────────────────────

function simulateLevel1WinRate(zoneKey) {
  var rng = mulberry32(SEED + 999);
  var wins = 0;
  var rounds = 100;

  for (var r = 0; r < rounds; r++) {
    var classRng = mulberry32(SEED + r * 100);
    for (var ci = 0; ci < CLASS_KEYS.length; ci++) {
      var className = CLASS_KEYS[ci];
      var cls = getClass(className);
      var base = getBaseStats(className);
      var derived = calcDerived({ str: base.str, agi: base.agi, int: base.int, vit: base.vit }, 1, className);

      var monster = pickMonster(zoneKey, classRng);
      var result = simulateHunt({
        class: className, level: 1, hp: derived.maxHp, maxHp: derived.maxHp,
        str: base.str, agi: base.agi, int: base.int, vit: base.vit,
      }, monster, classRng);

      if (result.winner === 'hero') wins++;
    }
  }

  return wins / (rounds * CLASS_KEYS.length) * 100;
}

// ─── Level-5 Forest win rate ───────────────────────────────────────────────

function simulateLevel5ForestWinRate() {
  var rng = mulberry32(SEED + 888);
  var wins = 0;
  var rounds = 100;

  for (var r = 0; r < rounds; r++) {
    for (var ci = 0; ci < CLASS_KEYS.length; ci++) {
      var className = CLASS_KEYS[ci];
      var cls = getClass(className);
      var base = getBaseStats(className);
      var primary = cls.primary;
      var stats = { str: base.str, agi: base.agi, int: base.int, vit: base.vit };
      stats[primary] += 15;
      var derived = calcDerived(stats, 5, className);

      var monster = pickMonster('forest', rng);
      var result = simulateHunt({
        class: className, level: 5, hp: derived.maxHp, maxHp: derived.maxHp,
        str: stats.str, agi: stats.agi, int: stats.int, vit: stats.vit,
      }, monster, rng);

      if (result.winner === 'hero') wins++;
    }
  }

  return wins / (rounds * CLASS_KEYS.length) * 100;
}

// ─── Main ──────────────────────────────────────────────────────────────────

function pct(n) {
  return Math.round(n * 100) / 100 + '%';
}

function main() {
  console.log('='.repeat(80));
  console.log('Emberfall Balance Simulation (seed=' + SEED + ')');
  console.log('='.repeat(80));

  var l1Meadows = simulateLevel1WinRate('meadows');
  var l1Crags = simulateLevel1WinRate('crags');

  console.log('\n--- Level-1 Win Rates ---');
  console.log('  Meadows:  ' + pct(l1Meadows) + '  (target: 70–90%)');
  console.log('  Crags:    ' + pct(l1Crags) + '  (target: ≤15%)');

  var l5Forest = simulateLevel5ForestWinRate();
  console.log('  Forest L5: ' + pct(l5Forest) + '  (target: 50–75%)');

  console.log('\n--- Per-Class Progression ---');
  console.log('Class        Hunts L1→5   Hunts L1→10   Crags Win%   Final Lv   Gold');
  console.log('-'.repeat(70));

  var targets = {
    l1Meadows: [0.70, 0.90],
    l1Crags: [0, 0.15],
    l5Forest: [0.50, 0.75],
    l1to5Hunts: [40, 70],
    l1to10Hunts: [150, 300],
  };

  var allMet = true;
  var classResults = [];

  for (var ci = 0; ci < CLASS_KEYS.length; ci++) {
    var className = CLASS_KEYS[ci];
    var sim = simulateClass(className);
    classResults.push(sim);
    var meadowsRate = sim.results.meadows.total > 0 ? sim.results.meadows.wins / sim.results.meadows.total : 0;
    var cragsRate = pct(sim.results.crags.wins / Math.max(1, sim.results.crags.total));
    console.log(className + '  L1->5: ' + String(sim.huntsL1to5).padStart(8) + '  L1->10: ' + String(sim.huntsL1to10).padStart(8) + '  Crags: ' + cragsRate.padStart(9) + '  Lv' + String(sim.finalLevel).padStart(6) + '  ' + String(sim.finalGold).padStart(6) + 'g');
  }

  var avgL1to5 = Math.round(classResults.reduce(function(s, c) { return s + c.huntsL1to5; }, 0) / classResults.length);
  var avgL1to10 = Math.round(classResults.reduce(function(s, c) { return s + c.huntsL1to10; }, 0) / classResults.length);

  console.log('\n--- Aggregate Targets ---');
  console.log('  L1→5 hunts:    ' + avgL1to5 + '  (target: 40–70) ' + (avgL1to5 >= 40 && avgL1to5 <= 70 ? '✓' : '✗'));
  console.log('  L1→10 hunts:   ' + avgL1to10 + '  (target: 150–300) ' + (avgL1to10 >= 150 && avgL1to10 <= 300 ? '✓' : '✗'));

  if (l1Meadows < targets.l1Meadows[0] || l1Meadows > targets.l1Meadows[1]) { console.log('  L1 Meadows:    ' + pct(l1Meadows) + '  ✗'); allMet = false; } else { console.log('  L1 Meadows:    ' + pct(l1Meadows) + '  ✓'); }
  if (l1Crags < targets.l1Crags[0] || l1Crags > targets.l1Crags[1]) { console.log('  L1 Crags:      ' + pct(l1Crags) + '  ✗'); allMet = false; } else { console.log('  L1 Crags:      ' + pct(l1Crags) + '  ✓'); }
  if (l5Forest < targets.l5Forest[0] || l5Forest > targets.l5Forest[1]) { console.log('  L5 Forest:     ' + pct(l5Forest) + '  ✗'); allMet = false; } else { console.log('  L5 Forest:     ' + pct(l5Forest) + '  ✓'); }

  console.log('\n--- Class Spread (max 15pp gap) ---');
  var meadowsRates = classResults.map(function(c) { return c.results.meadows.total > 0 ? c.results.meadows.wins / c.results.meadows.total : 0; });
  var mMax = Math.max.apply(null, meadowsRates);
  var mMin = Math.min.apply(null, meadowsRates);
  var mGap = (mMax - mMin) * 100;
  console.log('  Meadows: gap ' + pct(mGap / 100) + '  ' + (mGap <= 15 ? '✓' : '✗'));
  if (mGap > 15) allMet = false;

  console.log('\n' + '='.repeat(80));
  console.log(allMet ? 'ALL TARGETS MET ✓' : 'SOME TARGETS NOT MET ✗ — tune monster stats in a NEW migration');
  console.log('='.repeat(80));
}

main();