<?php
// +----------------------------------------------------------------------
// | YwxApp [ WE CAN DO IT JUST THINK ]
// +----------------------------------------------------------------------
// | Copyright (c) 2026-2036 http://ywxapp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Author: ywxapp<admin@ywxapp.cn>
// +----------------------------------------------------------------------

declare(strict_types=1);

namespace ywxapp\service;

use think\Exception;
use think\facade\Cache;
use think\facade\Config;

/**
 * 插件热重载服务
 * 
 * 功能特性：
 * - 开发环境下的插件热重载
 * - 无需重启即可加载插件修改
 * - 自动检测文件变更
 * - 支持选择性重载
 */
class AddonHotReload
{
    /** 热重载状态缓存键 */
    const RELOAD_STATUS_KEY = 'addon_hot_reload_status';
    
    /** 文件变更检测间隔（秒） */
    const CHECK_INTERVAL = 2;

    /**
     * 检查是否为开发环境
     * 
     * @return bool
     */
    private static function isDevelopmentEnvironment(): bool
    {
        return config('app.app_debug') === true;
    }

    /**
     * 热重载指定插件
     * 
     * @param string $addon 插件名称
     * @param bool $force 是否强制重载
     * @return bool
     * @throws Exception
     */
    public static function reloadAddon(string $addon, bool $force = false): bool
    {
        if (!self::isDevelopmentEnvironment()) {
            throw new Exception('热重载功能仅开发环境可用');
        }

        // 检查插件是否存在
        $addonPath = ADDON_PATH . $addon;
        if (!is_dir($addonPath)) {
            throw new Exception("插件不存在：{$addon}");
        }

        // 检查是否有文件变更
        if (!$force && !self::hasFileChanges($addon)) {
            return false; // 没有变更，无需重载
        }

        try {
            // 1. 清除插件相关缓存
            self::clearAddonCaches($addon);
            // 2. 重新加载插件配置
            $infoFile = $addonPath . DIRECTORY_SEPARATOR . 'info.php';
            if (is_file($infoFile)) {
                $info = include $infoFile;
                // 3. 重新注册插件服务
                if (isset($info['services']) && !empty($info['services'])) {
                    $services = $info['services'];
                    if (array_keys($services) === range(0, count($services) - 1)) {
                        $services = array_combine($services, $services);
                    }
                    app()->bind($services);
                }
                // 4. 重新加载事件监听
                if (isset($info['events']) && !empty($info['events'])) {
                    app()->loadEvent($info['events']);
                }
                // 5. 重新加载中间件
                if (isset($info['middleware']) && !empty($info['middleware'])) {
                    app()->middleware->import($info['middleware'], 'app');
                }
            }
            // 6. 更新重载状态
            self::updateReloadStatus($addon, [
                'reload_time' => time(),
                'status' => 'success',
                'files_changed' => self::getChangedFiles($addon)
            ]);
            
            \think\facade\Log::info("插件 {$addon} 热重载成功");
            return true;
            
        } catch (\Exception $e) {
            self::updateReloadStatus($addon, [
                'reload_time' => time(),
                'status' => 'failed',
                'error' => $e->getMessage()
            ]);
            
            \think\facade\Log::error("插件 {$addon} 热重载失败：" . $e->getMessage());
            throw $e;
        }
    }

    /**
     * 热重载所有已启用插件
     * 
     * @return array 重载结果
     */
    public static function reloadAlladdon(): array
    {
        if (!self::isDevelopmentEnvironment()) {
            throw new Exception('热重载功能仅开发环境可用');
        }

        $results = [];
        $addon = Config::get('addon', []);

        foreach ($addon as $addon) {
            if (!isset($addon['name']) || !($addon['state'] ?? false)) {
                continue;
            }

            try {
                $reloaded = self::reloadAddon($addon['name']);
                $results[$addon['name']] = [
                    'success' => true,
                    'reloaded' => $reloaded
                ];
            } catch (\Exception $e) {
                $results[$addon['name']] = [
                    'success' => false,
                    'error' => $e->getMessage()
                ];
            }
        }

        return $results;
    }

    /**
     * 检查插件是否有文件变更
     * 
     * @param string $addon 插件名称
     * @return bool
     */
    private static function hasFileChanges(string $addon): bool
    {
        $addonPath = ADDON_PATH . $addon;
        $lastCheckKey = 'addon_file_check_' . $addon;
        $lastCheckTime = Cache::get($lastCheckKey, 0);
        
        // 检查间隔限制
        if (time() - $lastCheckTime < self::CHECK_INTERVAL) {
            return false;
        }
        
        $currentHash = self::calculateDirectoryHash($addonPath);
        $lastHashKey = 'addon_file_hash_' . $addon;
        $lastHash = Cache::get($lastHashKey, '');
        
        // 更新检查时间
        Cache::set($lastCheckKey, time(), 60);
        
        if ($currentHash !== $lastHash) {
            Cache::set($lastHashKey, $currentHash, 3600);
            return true;
        }
        
        return false;
    }

    /**
     * 计算目录哈希值
     * 
     * @param string $directory 目录路径
     * @return string
     */
    private static function calculateDirectoryHash(string $directory): string
    {
        $hash = '';
        $iterator = new \RecursiveIteratorIterator(
            new \RecursiveDirectoryIterator($directory, \RecursiveDirectoryIterator::SKIP_DOTS),
            \RecursiveIteratorIterator::SELF_FIRST
        );

        foreach ($iterator as $file) {
            if ($file->isFile()) {
                $hash .= md5_file($file->getPathname()) . $file->getMTime();
            }
        }

        return md5($hash);
    }

    /**
     * 获取变更的文件列表
     * 
     * @param string $addon 插件名称
     * @return array
     */
    private static function getChangedFiles(string $addon): array
    {
        // 这里简化处理，实际可以记录具体的文件变更
        return ['all_files']; // 表示所有文件都可能已变更
    }

    /**
     * 清除插件相关缓存
     * 
     * @param string $addon 插件名称
     */
    private static function clearAddonCaches(string $addon): void
    {
        // 清除配置缓存
        Cache::delete('addon_config_' . $addon);
        Cache::delete('addon_config_version_' . $addon);
        
        // 清除插件加载缓存
        AppService::clearAddonCache();
        
        // 清除性能监控数据
        AddonPerformanceMonitor::clearPerformanceData($addon);
    }

    /**
     * 更新重载状态
     * 
     * @param string $addon 插件名称
     * @param array $status 状态信息
     */
    private static function updateReloadStatus(string $addon, array $status): void
    {
        $statusKey = self::RELOAD_STATUS_KEY . '_' . $addon;
        Cache::set($statusKey, $status, 3600);
    }

    /**
     * 获取插件重载状态
     * 
     * @param string $addon 插件名称
     * @return array
     */
    public static function getReloadStatus(string $addon): array
    {
        $statusKey = self::RELOAD_STATUS_KEY . '_' . $addon;
        return Cache::get($statusKey, [
            'status' => 'never_reloaded',
            'reload_time' => null
        ]);
    }

    /**
     * 启用自动热重载监听
     * 
     * 注意：这需要在适当的地方调用，比如在中间件中
     */
    public static function enableAutoReload(): void
    {
        if (!self::isDevelopmentEnvironment()) {
            return;
        }

        // 检查是否有插件需要重载
        $addon = Config::get('addon', []);
        foreach ($addon as $addon) {
            if (!isset($addon['name']) || !($addon['state'] ?? false)) {
                continue;
            }

            try {
                if (self::hasFileChanges($addon['name'])) {
                    self::reloadAddon($addon['name']);
                }
            } catch (\Exception $e) {
                // 静默处理错误，避免影响正常请求
                \think\facade\Log::warning("自动热重载失败：{$addon['name']} - " . $e->getMessage());
            }
        }
    }

    /**
     * 获取热重载统计信息
     * 
     * @return array
     */
    public static function getReloadStatistics(): array
    {
        $stats = [
            'total_reloads' => 0,
            'successful_reloads' => 0,
            'failed_reloads' => 0,
            'addon' => []
        ];

        $addon = Config::get('addon', []);
        foreach ($addon as $addon) {
            if (!isset($addon['name'])) {
                continue;
            }

            $status = self::getReloadStatus($addon['name']);
            $stats['addon'][$addon['name']] = $status;

            if ($status['status'] !== 'never_reloaded') {
                $stats['total_reloads']++;
                if ($status['status'] === 'success') {
                    $stats['successful_reloads']++;
                } else {
                    $stats['failed_reloads']++;
                }
            }
        }

        return $stats;
    }

    /**
     * 清除所有热重载状态
     */
    public static function clearAllReloadStatus(): void
    {
        $addon = Config::get('addon', []);
        foreach ($addon as $addon) {
            if (isset($addon['name'])) {
                Cache::delete(self::RELOAD_STATUS_KEY . '_' . $addon['name']);
                Cache::delete('addon_file_check_' . $addon['name']);
                Cache::delete('addon_file_hash_' . $addon['name']);
            }
        }
    }
}