import { createServer } from 'vite';

const validRanks = new Set(['common', 'treasure']);

const server = await createServer({
  logLevel: 'error',
  server: { middlewareMode: true },
  appType: 'custom'
});

try {
  const { battleScenarios } = await server.ssrLoadModule('/src/game/data/battles.ts');
  const { campaignRecruitUnits } = await server.ssrLoadModule('/src/game/data/scenario.ts');
  const { itemCatalog, equipmentSlots, equipmentExpToNext } = await server.ssrLoadModule('/src/game/data/battleItems.ts');

  const errors = [];
  const itemEntries = Object.entries(itemCatalog);
  const itemKeys = new Set(itemEntries.map(([itemId]) => itemId));
  const slotKeys = new Set(equipmentSlots);

  validateItemCatalog(errors, itemEntries, slotKeys);
  validateUnitEquipment(errors, collectBattleUnits(battleScenarios), itemCatalog, itemKeys, equipmentSlots, equipmentExpToNext);
  validateUnitEquipment(
    errors,
    (campaignRecruitUnits ?? []).map((unit) => ({ context: `campaignRecruitUnits/${unit.id}`, unit })),
    itemCatalog,
    itemKeys,
    equipmentSlots,
    equipmentExpToNext
  );

  if (errors.length) {
    console.error(`Equipment catalog data verification failed with ${errors.length} issue(s):`);
    errors.slice(0, 120).forEach((error) => console.error(`- ${error}`));
    if (errors.length > 120) {
      console.error(`- ...and ${errors.length - 120} more`);
    }
    process.exitCode = 1;
  } else {
    console.log(
      `Verified ${itemEntries.length} equipment catalog items and ${Object.keys(battleScenarios).length} battle equipment loadouts.`
    );
  }
} finally {
  await server.close();
}

function validateItemCatalog(errors, itemEntries, slotKeys) {
  const names = new Map();

  itemEntries.forEach(([itemId, item]) => {
    const context = `itemCatalog/${itemId}`;
    if (!item || typeof item !== 'object') {
      errors.push(`${context}: must be an item object`);
      return;
    }

    if (item.id !== itemId) {
      errors.push(`${context}: item.id "${item.id}" does not match catalog key`);
    }
    assertNonEmptyString(errors, item.name, `${context}: name`);
    assertNonEmptyString(errors, item.description, `${context}: description`);

    if (!slotKeys.has(item.slot)) {
      errors.push(`${context}: unknown equipment slot "${item.slot}"`);
    }
    if (!validRanks.has(item.rank)) {
      errors.push(`${context}: unknown rank "${item.rank}"`);
    }
    if (!Array.isArray(item.effects) || item.effects.length === 0) {
      errors.push(`${context}: effects must contain at least one entry`);
    } else {
      item.effects.forEach((effect, index) => {
        assertNonEmptyString(errors, effect, `${context}: effects[${index}]`);
      });
    }

    ['attackBonus', 'defenseBonus', 'strategyBonus'].forEach((bonusKey) => {
      const value = item[bonusKey];
      if (value !== undefined && (!Number.isInteger(value) || value < 0 || value > 20)) {
        errors.push(`${context}: invalid ${bonusKey} ${value}`);
      }
    });

    if (typeof item.name === 'string') {
      const existingItemId = names.get(item.name);
      if (existingItemId) {
        errors.push(`${context}: duplicate item name "${item.name}" also used by ${existingItemId}`);
      }
      names.set(item.name, itemId);
    }
  });
}

function validateUnitEquipment(errors, unitEntries, itemCatalog, itemKeys, equipmentSlots, equipmentExpToNext) {
  unitEntries.forEach(({ context, unit }) => {
    if (!unit?.equipment) {
      errors.push(`${context}: missing equipment`);
      return;
    }

    equipmentSlots.forEach((slot) => {
      const state = unit.equipment[slot];
      if (!state) {
        errors.push(`${context}: missing ${slot} equipment`);
        return;
      }
      if (!itemKeys.has(state.itemId)) {
        errors.push(`${context}: unknown ${slot} item "${state.itemId}"`);
      } else if (itemCatalog[state.itemId].slot !== slot) {
        errors.push(`${context}: ${slot} item "${state.itemId}" belongs to ${itemCatalog[state.itemId].slot}`);
      }
      if (!Number.isInteger(state.level) || state.level < 1 || state.level > 9) {
        errors.push(`${context}: invalid ${slot} level ${state.level}`);
      }
      if (!Number.isInteger(state.exp) || state.exp < 0) {
        errors.push(`${context}: invalid ${slot} exp ${state.exp}`);
      } else if (state.level < 9 && state.exp >= equipmentExpToNext(state.level)) {
        errors.push(`${context}: ${slot} exp ${state.exp} should be below next level threshold ${equipmentExpToNext(state.level)}`);
      }
    });
  });
}

function collectBattleUnits(battleScenarios) {
  return Object.entries(battleScenarios).flatMap(([battleId, scenario]) =>
    scenario.units.map((unit) => ({ context: `${battleId}/${unit.id}`, unit }))
  );
}

function assertNonEmptyString(errors, value, context) {
  if (typeof value !== 'string' || value.trim().length === 0) {
    errors.push(`${context} must be a non-empty string`);
  }
}