<?php
namespace Game\System;

use Game\Event\Event;
use Game\Event\EventListenerInterface;
use Game\Event\EventDispatcher;
use Game\Model\NPC;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Component\Console\Helper\QuestionHelper;
use Symfony\Component\Console\Question\Question;

/**
 * InteractionSystem: 负责处理玩家与 NPC 的对话和交互流程。
 */
class InteractionSystem implements EventListenerInterface {

    private EventDispatcher $dispatcher;
    private StateManager $stateManager;

    // 输入依赖
    private InputInterface $input;
    private OutputInterface $output;
    private QuestionHelper $helper;

    public function __construct(EventDispatcher $dispatcher, StateManager $stateManager, InputInterface $input, OutputInterface $output, QuestionHelper $helper) {
        $this->dispatcher = $dispatcher;
        $this->stateManager = $stateManager;
        $this->input = $input;
        $this->output = $output;
        $this->helper = $helper;
    }

    public function handleEvent(Event $event): void {
        switch ($event->getType()) {
            case 'AttemptInteractEvent':
                // 假设 MapSystem 会提供当前 Tile 上的 NPC ID
                $npcId = $event->getPayload()['npcId'];
                $this->startInteraction($npcId);
                break;
        }
    }

    /**
     * 1. 初始化 NPC 交互
     */
    private function startInteraction(string $npcId): void {
        $npc = $this->loadNPC($npcId);
        if (!$npc) {
            $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => "这里没有人可以交谈。"]));
            return;
        }

        $this->dispatcher->dispatch(new Event('SystemMessage', [
            'message' => "👤 你走近了 <fg=cyan;options=bold>{$npc->getName()}</>。"
        ]));

        // 启动对话流程
        $this->dialogueLoop($npc);

        // 交互结束后，重新打印主菜单请求
        $this->dispatcher->dispatch(new Event('ShowMenuEvent'));
    }

    /**
     * 2. 核心对话循环
     */
    private function dialogueLoop(NPC $npc): void {
        $currentDialogueKey = 'greeting';
        $running = true;

        while ($running) {

            // 打印 NPC 对话
            $text = $npc->getDialogueText($currentDialogueKey);
            $this->dispatcher->dispatch(new Event('SystemMessage', [
                'message' => "<fg=cyan>{$npc->getName()}</>：<fg=white>{$text}</>"
            ]));

            // 检查交互类型并获取玩家选择
            $choice = $this->promptPlayerChoice();

            switch ($choice) {
                case 'T': // 触发任务/特殊事件
                    $this->dispatcher->dispatch(new Event('QuestCheckEvent', ['npcId' => $npc->id]));
                    $currentDialogueKey = 'quest_response';
                    break;
                case 'S': // 触发商店
                    $this->dispatcher->dispatch(new Event('OpenShopEvent', ['npcId' => $npc->id]));
                    $currentDialogueKey = 'shop_response';
                    break;
                case 'E': // 结束对话
                    $running = false;
                    $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => "🤝 你结束了与 {$npc->getName()} 的对话。"]));
                    break;
                default:
                    $this->dispatcher->dispatch(new Event('SystemMessage', ['message' => '无效的交互指令。']));
            }
        }
    }

    /**
     * 获取玩家交互指令
     */
    private function promptPlayerChoice(): string {
        $this->dispatcher->dispatch(new Event('SystemMessage', [
            'message' => "\n--- 交互菜单 --- [T] 任务 | [S] 商店 | [E] 结束"
        ]));

        $question = new Question("> 请选择指令 (T/S/E)：");
        $choice = strtoupper($this->helper->ask($this->input, $this->output, $question) ?? '');

        return $choice;
    }

    /**
     * 模拟从配置中加载 NPC 数据
     */
    private function loadNPC(string $id): ?NPC {
        $data = match ($id) {
            'VILLAGER_1' => [
                'name' => '老村长',
                'dialogue' => [
                    'greeting' => '你好，旅行者。你看起来很强大。',
                    'quest_response' => '你想要帮忙吗？我们的地窖里有老鼠。',
                    'shop_response' => '我现在没有东西卖给你。',
                ]
            ],
            default => null,
        };

        if ($data) {
            return new NPC($id, $data['name'], $data['dialogue']);
        }
        return null;
    }
}