<?php
namespace Game\System;

use Game\Database\EnemyRepository;
use Game\Database\ItemRepository;
use Game\Event\Event;
use Game\Event\EventListenerInterface;
use Game\Event\EventDispatcher;
use Game\Model\Enemy;
use Game\Model\Item;

/**
 * LootService: 负责处理物品掉落、背包管理和物品获取。
 */
class LootService implements EventListenerInterface {

    private EventDispatcher $dispatcher;
    private StateManager $stateManager;
// ... 现有属性 ...
    private ItemRepository $itemRepository;
    private EnemyRepository $enemyRepository;
// ⭐ 修正构造函数：注入 Repositories
    public function __construct(EventDispatcher $dispatcher, StateManager $stateManager, ItemRepository $itemRepository, EnemyRepository $enemyRepository) {
        $this->dispatcher = $dispatcher;
        $this->stateManager = $stateManager;
        $this->itemRepository = $itemRepository;
        $this->enemyRepository = $enemyRepository;
    }

    public function createEnemy(string $id): ?Enemy {
        // ⭐ 使用 Repository 获取数据
        $data = $this->enemyRepository->find($id);
        if (!$data) {
            $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => "❌ 错误：敌人ID '{$id}' 不存在。"]));
            return null;
        }

        // ⭐ 修正实例化 Enemy：传入 loot_table
        return new Enemy(
            $data['id'],
            $data['name'],
            $data['health'],
            $data['attack'],
            $data['defense'],
            $data['xp'],
            $data['loot'] ?? [] // 传递 loot_table
        );
    }

    public function handleEvent(Event $event): void {
        switch ($event->getType()) {
            case 'LootDropEvent':
                $enemyId = $event->getPayload()['enemyId'];
                // LootDropEvent 应该由 BattleService 在敌人死亡时触发
                $this->handleLootDrop($enemyId);
                break;
            case 'LootFoundEvent': // 响应 MapSystem 探索时发现的宝箱
                $lootId = $event->getPayload()['lootId'];
                $this->handleLootFound($lootId);
                break;
            case 'ShopPurchaseEvent': // ⭐ 响应商店购买
                $itemId = $event->getPayload()['itemId'];
                $this->giveItemToPlayer($itemId);
                break;
            // ⭐ 响应遇敌事件
            case 'EncounterEnemyEvent':
                $enemyId = $event->getPayload()['enemyId'];
                $newEnemy = $this->createEnemy($enemyId);

                if ($newEnemy) {
                    // 通知 BattleService 启动战斗
                    $this->dispatcher->dispatch(new Event('StartBattleEvent', ['enemy' => $newEnemy]));
                }
                break;
        }
    }

    /**
     * ⭐ 修正方法：处理敌人死亡时的掉落逻辑（从配置中加载数据）
     */
    private function handleLootDrop(string $enemyId): void {

        // 1. 获取敌人配置数据
        $enemyData = $this->enemyRepository->find($enemyId);

        if (!$enemyData) {
            $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => "❌ 错误：无法找到敌人 {$enemyId} 的掉落配置。"]));
            return;
        }

        // --- 2. 掉落金币 (从配置中获取范围) ---
        $minGold = $enemyData['min_gold'] ?? 5; // 使用配置，默认 5
        $maxGold = $enemyData['max_gold'] ?? 15; // 使用配置，默认 15

        $goldAmount = rand($minGold, $maxGold);
        $player = $this->stateManager->getPlayer();
        $player->gainGold($goldAmount);

        $this->dispatcher->dispatch(new Event('SystemMessage', [
            'message' => "💰 获得了 <fg=yellow>{$goldAmount}</> 金币。"
        ]));

        // --- 3. 掉落物品 (从配置的 loot_table 中获取) ---
        $lootTable = $enemyData['loot_table'] ?? [];

        if (!empty($lootTable)) {
            $droppedItemId = $this->getRandomItemIdFromLootTable($lootTable);

            if ($droppedItemId !== null) { // 成功掉落物品
                $this->giveItemToPlayer($droppedItemId);
            } else {
                $this->dispatcher->dispatch(new Event('SystemMessage', [
                    'message' => "战利品很少，只找到了一些零钱。"
                ]));
            }
        } else {
            $this->dispatcher->dispatch(new Event('SystemMessage', [
                'message' => "战利品很少，只找到了一些零钱。"
            ]));
        }
    }

    /**
     * ⭐ 新增方法：根据权重随机选择物品 ID
     */
    private function getRandomItemIdFromLootTable(array $lootTable): ?int {
        $totalChance = array_sum(array_column($lootTable, 'chance'));

        // 随机数范围是 1 到 100
        $randValue = rand(1, 100);

        // 如果随机值大于总几率，则表示未掉落任何物品
        // 例如：总几率为 80，随机数是 85，则不掉落
        if ($randValue > $totalChance) {
            return null;
        }

        $currentChance = 0;
        foreach ($lootTable as $item) {
            $currentChance += $item['chance'];
            if ($randValue <= $currentChance) {
                // 确保 item_id 是整数类型
                return (int)$item['item_id'];
            }
        }

        return null;
    }

    /**
     * 处理探索时发现的宝箱/固定物品 (保持不变)
     */
    private function handleLootFound($lootId): void {

    }

    /**
     * 核心逻辑：创建物品实例并添加到玩家背包 (保持不变)
     */
    private function giveItemToPlayer($itemId): void {
        // ...
        $item = $this->itemRepository->createItem($itemId);

        if (!$item) {
            $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => "❌ 物品ID '{$itemId}' 不存在，无法获得。"]));
            return;
        }

        $player = $this->stateManager->getPlayer();
        $player->addItem($item);

        $this->dispatcher->dispatch(new Event('SystemMessage', [
            'message' => "➕ 获得了物品：<fg=green>{$item->name}</>！"
        ]));

        // 触发 InventoryUpdateEvent (未来用于 UI 实时更新)
        $this->dispatcher->dispatch(new Event('InventoryUpdateEvent', ['playerInventory' => $player->getInventory()]));
    }
}