<?php
namespace app\service;

use think\facade\Cache;
use think\facade\Request;
use think\facade\Db;
use think\facade\Log;

class VisitStatsService
{
    // Redis实例
    protected $redis;
    
    // 键名前缀
    protected $prefix = 'stats:';
    
    public function __construct()
    {
        try {
            // 获取Redis处理器
            $this->redis = Cache::store('redis')->handler();
        } catch (\Exception $e) {
            // Redis连接失败，使用文件缓存
            $this->redis = Cache::store('file')->handler();
            Log::error('Redis连接失败，已切换到文件缓存：' . $e->getMessage());
        }
    }
    
    /**
     * 记录访问并更新统计数据
     */
    public function recordVisit(string $page = 'home', string $userId = null): array
    {
        try {
            $date = date('Y-m-d');
            $hour = date('H');
            $userId = $userId ?? Request::ip();
            
            // 使用管道提高性能
            $pipe = $this->redis->multi();
            
            // 总访问量(PV)
            $pipe->incr($this->prefix.'total_visits');
            
            // 每日访问量
            $pipe->incr($this->prefix.'daily:'.$date);
            
            // 页面统计
            $pipe->zIncrBy($this->prefix.'page_views', 1, $page);
            
            // UV统计(使用HyperLogLog节省内存)
            $pipe->pfAdd($this->prefix.'uv:'.$date, [$userId]);
            
            // 时段统计
            $pipe->hIncrBy($this->prefix.'hourly:'.$date, $hour, 1);
            
            // 执行所有命令
            $result = $pipe->exec();
            
            // 使用Redis锁控制更新频率，每5分钟更新一次数据库
            $lockKey = $this->prefix.'update_lock:'.$date;
            if (!$this->redis->exists($lockKey)) {
                $this->redis->setex($lockKey, 300, 1); // 5分钟锁
                $this->updateDailyStats($date, [
                    'total_visits' => $result[0],
                    'daily_visits' => $result[1],
                    'unique_visitors' => $this->getUniqueVisitors($date)
                ]);
            }
            
            return [
                'total' => $result[0],
                'daily' => $result[1],
                'page'  => $result[2],
                'uv'    => $result[3],
                'hourly'=> $result[4]
            ];
        } catch (\Exception $e) {
            Log::error('访问统计失败：' . $e->getMessage());
            return [
                'total' => 0,
                'daily' => 0,
                'page'  => 0,
                'uv'    => 0,
                'hourly'=> 0
            ];
        }
    }
    
    /**
     * 更新每日统计数据
     */
    protected function updateDailyStats(string $date, array $stats)
    {
        try {
            // 获取其他统计数据
            $otherStats = [
                'total_users' => Db::name('users')->count(),
                'new_users' => Db::name('users')->whereDay('create_time', $date)->count(),
                'total_articles' => Db::name('articles')->where('delete_time', null)->count(),
                'daily_articles' => Db::name('articles')->whereDay('create_time', $date)->count(),
                'article_views' => Db::name('articles')->whereDay('update_time', $date)->sum('views'),
                'total_resources' => Db::name('resources')->where('delete_time', null)->count(),
                'daily_resources' => Db::name('resources')->whereDay('create_time', $date)->count(),
                'resource_downloads' => Db::name('resources')->whereDay('update_time', $date)->sum('downloads')
            ];
            
            // 只在调试模式下记录日志
            if (config('app.debug')) {
                Log::info('统计数据：' . json_encode($otherStats, JSON_UNESCAPED_UNICODE));
            }
            
            // 合并统计数据
            $stats = array_merge($stats, $otherStats);
            
            // 检查记录是否存在
            $exists = Db::name('daily_stats')->where('date', $date)->find();
            
            if ($exists) {
                // 更新已存在的记录
                Db::name('daily_stats')->where('date', $date)->update([
                    'total_users' => $stats['total_users'],
                    'new_users' => $stats['new_users'],
                    'total_visits' => $stats['total_visits'],
                    'daily_visits' => $stats['daily_visits'],
                    'unique_visitors' => $stats['unique_visitors'],
                    'total_articles' => $stats['total_articles'],
                    'daily_articles' => $stats['daily_articles'],
                    'article_views' => $stats['article_views'],
                    'total_resources' => $stats['total_resources'],
                    'daily_resources' => $stats['daily_resources'],
                    'resource_downloads' => $stats['resource_downloads']
                ]);
            } else {
                // 插入新记录
                Db::name('daily_stats')->insert([
                    'date' => $date,
                    'total_users' => $stats['total_users'],
                    'new_users' => $stats['new_users'],
                    'total_visits' => $stats['total_visits'],
                    'daily_visits' => $stats['daily_visits'],
                    'unique_visitors' => $stats['unique_visitors'],
                    'total_articles' => $stats['total_articles'],
                    'daily_articles' => $stats['daily_articles'],
                    'article_views' => $stats['article_views'],
                    'total_resources' => $stats['total_resources'],
                    'daily_resources' => $stats['daily_resources'],
                    'resource_downloads' => $stats['resource_downloads']
                ]);
            }
        } catch (\Exception $e) {
            Log::error('更新统计数据失败：' . $e->getMessage());
        }
    }
    
    /**
     * 获取总访问量
     */
    public function getTotalVisits(): int
    {
        try {
            return (int)$this->redis->get($this->prefix.'total_visits');
        } catch (\Exception $e) {
            Log::error('获取总访问量失败：' . $e->getMessage());
            return 0;
        }
    }
    
    /**
     * 获取当日访问量
     */
    public function getDailyVisits(string $date = null): int
    {
        try {
            $date = $date ?? date('Y-m-d');
            return (int)$this->redis->get($this->prefix.'daily:'.$date);
        } catch (\Exception $e) {
            Log::error('获取当日访问量失败：' . $e->getMessage());
            return 0;
        }
    }
    
    /**
     * 获取独立访客数(UV)
     */
    public function getUniqueVisitors(string $date = null): int
    {
        try {
            $date = $date ?? date('Y-m-d');
            return $this->redis->pfCount($this->prefix.'uv:'.$date);
        } catch (\Exception $e) {
            Log::error('获取独立访客数失败：' . $e->getMessage());
            return 0;
        }
    }
}