<?php

namespace App\Service\common;

use Illuminate\Support\Facades\Redis;

class RedisService
{

    private static mixed $_instance;

    private $prefix = 'default';

    private $redis;

    /**
     * 获取实例
     * @return null|static
     */
    public static function getInstance(): null|static
    {
        $name = get_called_class();
        if (!isset(self::$_instance[$name])) {
            self::$_instance[$name] = new static();
        }

        return self::$_instance[$name];
    }

    /**
     * 初始化
     * @param string $prefix
     * @return RedisService
     */
    public function init(string $prefix = 'default'): static
    {
        $this->redis = Redis::class;
        $this->prefix = $prefix;
        return $this;
    }

    /**
     * 设置缓存
     * @param $key
     * @param $value
     * @param int $expire
     * @return true
     */
    public function set($key, $value, int $expire = 0): true
    {
        $this->redis::set($this->prefix . $key, $value);
        if ($expire > 0) {
            $this->redis::expire($this->prefix . $key, $expire);
        }
        return true;
    }

    /**
     * 累加
     * @param $key
     * @param int $value
     * @param int $expire
     * @return true
     */
    public function incr($key, int $value = 1, int $expire = 0): true
    {
        $this->redis::incr($this->prefix . $key, $value);
        if ($expire > 0) {
            $this->redis::expire($this->prefix . $key, $expire);
        }
        return true;
    }

    /**
     * 获取缓存
     *
     * @param $key
     * @return mixed
     */
    public function get($key): mixed
    {
        return $this->redis::get($this->prefix . $key);
    }

    /**
     * 删除缓存
     * @param $key
     * @return bool
     */
    public function del($key): bool
    {
        return $this->redis::del($this->prefix . $key);
    }

    /**
     * 清空当前前缀下的全部键
     *
     * 菜单这类按角色分片缓存的数据，改了菜单树要一次性失效所有角色的副本。
     * KEYS 的返回值带着 redis 客户端自身的 prefix，直接回传给 del 会二次拼前缀，所以要先剥掉。
     * @return int 删除的键数量
     */
    public function delAll(): int
    {
        $keys = $this->redis::keys($this->prefix . '*');
        if (empty($keys)) {
            return 0;
        }
        $clientPrefix = (string) config('database.redis.options.prefix');
        $count = 0;
        foreach ($keys as $key) {
            if ($clientPrefix !== '' && str_starts_with($key, $clientPrefix)) {
                $key = substr($key, strlen($clientPrefix));
            }
            $this->redis::del($key);
            $count++;
        }
        return $count;
    }
}