<?php
namespace Game\System;

use Game\Model\Item;
use Game\Model\Player;
use Game\Event\Event;
use Game\Event\EventDispatcher;
use Game\Model\Quest;

/**
 * SaveLoadService: 负责将玩家状态持久化，并支持装备与地图位置的还原。
 */
class SaveLoadService {

    private EventDispatcher $dispatcher;
    private StateManager $stateManager;
    private string $savePath;

    public function __construct(EventDispatcher $dispatcher, StateManager $stateManager, string $savePath = 'save/player.json') {
        $this->dispatcher = $dispatcher;
        $this->stateManager = $stateManager;
        $this->savePath = $savePath;

        if (!is_dir(dirname($this->savePath))) {
            mkdir(dirname($this->savePath), 0777, true);
        }
    }

    public function hasSaveFile(): bool {
        return file_exists($this->savePath);
    }

    /**
     * 将完整游戏状态保存
     */
    public function saveGame(): void {
        $player = $this->stateManager->getPlayer();
        $currentTile = $this->stateManager->getCurrentTile();

        if (!$player) return;

        try {
            // 1. 序列化背包
            $serializedInventory = array_map(fn(Item $item) => $this->itemToData($item), $player->getInventory());

            // 2. ⭐ 新增：序列化当前装备槽位
            $serializedEquipment = [];
            foreach ($player->getEquipment() as $slot => $item) {
                $serializedEquipment[$slot] = $item ? $this->itemToData($item) : null;
            }

            // 3. 序列化任务
            $activeQuests = [];
            foreach ($player->getActiveQuests() as $quest) {
                $activeQuests[] = [
                    'config' => $quest->toArray(),
                    'currentCount' => $quest->getCurrentCount()
                ];
            }

            $data = [
                'player' => [
                    'name' => $player->getName(),
                    'health' => $player->getHealth(),
                    'maxHealth' => $player->getMaxHealth(),
                    'base_attack' => $player->attack, // 保存基础值
                    'base_defense' => $player->defense,
                    'level' => $player->getLevel(),
                    'currentXp' => $player->getCurrentXp(),
                    'gold' => $player->getGold(),
                    'inventory' => $serializedInventory,
                    'equipment' => $serializedEquipment, // ⭐ 装备持久化
                    'activeQuests' => $activeQuests,
                    'completedQuests' => $player->getCompletedQuests(),
                ],
                'world' => [
                    'currentTileId' => $currentTile->id // ⭐ 位置持久化
                ]
            ];

            file_put_contents($this->savePath, json_encode($data, JSON_PRETTY_PRINT));
            $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => '💾 进度已安全存入魔法卷轴！']));

        } catch (\Exception $e) {
            $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => '❌ 存档失败: ' . $e->getMessage()]));
        }
    }

    /**
     * 加载存档并还原所有复杂对象
     */
    public function loadGame(): ?Player {
        if (!$this->hasSaveFile()) return null;

        try {
            $data = json_decode(file_get_contents($this->savePath), true);
            $pData = $data['player'];

            // 1. 创建基础玩家对象
            $player = new Player($pData['name'], $pData['maxHealth'], $pData['base_attack'], $pData['base_defense']);
            $player->setHealth($pData['health']);
            $player->setLevel($pData['level']);
            $player->setCurrentXp($pData['currentXp']);
            $player->setGold($pData['gold']);
            $player->setCompletedQuests($pData['completedQuests'] ?? []);

            // 2. 还原背包物品 (包含 Stats 属性)
            $inventory = array_map(fn($itemData) => $this->dataToItem($itemData), $pData['inventory']);
            $player->setInventory($inventory);

            // 3. ⭐ 还原装备 (确保 Stats 效果重新生效)
            foreach ($pData['equipment'] as $slot => $itemData) {
                if ($itemData) {
                    $item = $this->dataToItem($itemData);
                    $player->equipItem($item); // 使用装备方法，确保属性刷新
                }
            }

            // 4. 还原任务进度
            $activeQuests = [];
            foreach ($pData['activeQuests'] as $qData) {
                $config = $qData['config'];
                $quest = new Quest($config['id'], $config['name'], $config['description'], $config['type'], $config['target'], $config['rewards']);
                $quest->setCurrentCount($qData['currentCount']);
                $activeQuests[$config['id']] = $quest;
            }
            $player->setActiveQuests($activeQuests);

            // 5. ⭐ 还原地图位置
            if (isset($data['world']['currentTileId'])) {
                $this->stateManager->setCurrentTileId($data['world']['currentTileId']);
            }

            $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => '📂 欢迎回来，勇者！进度已加载。']));
            return $player;

        } catch (\Exception $e) {
            $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => '❌ 加载失败: ' . $e->getMessage()]));
            return null;
        }
    }

    /**
     * 辅助：Item 转 数组 (包含新增的 stats 字段)
     */
    private function itemToData(Item $item): array {
        return [
            'id' => $item->id,
            'name' => $item->name,
            'type' => $item->type,
            'description' => $item->description,
            'value' => $item->value,
            'effects' => $item->effects ?? [],
            'stats' => $item->stats ?? [], // ⭐ 对应 D 阶段的属性加成
            'slot' => $item->slot ?? null
        ];
    }

    /**
     * 辅助：数组 转 Item
     */
    private function dataToItem(array $d): Item {
        $item = new Item($d['id'], $d['name'], $d['type'], $d['description'], $d['value'], $d['effects']);
        $item->stats = $d['stats'] ?? [];
        $item->slot = $d['slot'] ?? null;
        return $item;
    }
}