<?php

namespace dominion\cache;

use Yii;
use yii\helpers\Inflector;
use Redis;
use RedisException;
use RedisSentinel;

class SentinelConnection extends Connection
{
    /**
     * Команды достапные на любой ноде master или slave
     * @var array
     */
    public $redisSlaveCommands = [
        'GET',
        'HGET',
        //нужно перечислить все, но пока так
    ];

    public $slaves = [];

    public function executeCommand($name, $params = [])
    {
        $this->open();
        Yii::debug("Executing Redis Command: {$name} " . var_export($params, true), __METHOD__);

        $redis = $this->redis; //мастер
        $redisCommand = strtoupper(Inflector::camel2words($name, false));
        if (in_array($redisCommand, $this->redisSlaveCommands))
        {
            if(!empty($this->slaves))
            {
                //читаем из произвольного раба
                $redis = $this->slaves[array_rand($this->slaves)];
            }
        }

        return $redis->{$name}(...$params);
    }

    protected function isValidServer(mixed $server): bool
    {
        return is_array($server) && isset($server['ip']) && isset($server['port']);
    }

    public function createClient(array $config): Redis
    {
        $service = $config['sentinel_service'] ?? 'mymaster';

        $hosts = is_array($config['sentinel_host']) ? $config['sentinel_host'] : [$config['sentinel_host']];
        foreach ($hosts as $host)
        {
            $newConfig = $config;
            $newConfig['sentinel_host'] = $host;
            $sentinel = $this->connectToSentinel($newConfig);

            if ($sentinel->ping())
            {
                break;
            }
        }
        $master = $sentinel->master($service);
        if (!$this->isValidServer($master))
        {
            throw new RedisException(sprintf("No master found for service '%s'.", $service));
        }
        $slaves = $sentinel->slaves($service);
        foreach ($slaves as $slave)
        {
            if ($this->isValidServer($slave))
            {
                //могут быть проблемв из-за большого количества подключений
                $this->slaves[] = parent::createClient(array_merge($config, [
                    'host' => $slave['ip'],
                    'port' => $slave['port'],
                ]));
            }
        }

        return parent::createClient(array_merge($config, [
                'host' => $master['ip'],
                'port' => $master['port'],
        ]));
    }

    private function connectToSentinel(array $config): RedisSentinel
    {
        $host = $config['sentinel_host'] ?? '';
        $port = $config['sentinel_port'] ?? 26379;
        $timeout = $config['sentinel_timeout'] ?? 0.2;
        $persistent = $config['sentinel_persistent'] ?? null;
        $retryInterval = $config['sentinel_retry_interval'] ?? 0;
        $readTimeout = $config['sentinel_read_timeout'] ?? 0;
        $username = $config['sentinel_username'] ?? '';
        $password = $config['sentinel_password'] ?? '';
        $ssl = $config['sentinel_ssl'] ?? null;

        if (strlen(trim($host)) === 0)
        {
            throw new ConfigurationException('No host has been specified for the Redis Sentinel connection.');
        }

        $auth = null;
        if (strlen(trim($username)) !== 0 && strlen(trim($password)) !== 0)
        {
            $auth = [$username, $password];
        }
        elseif (strlen(trim($password)) !== 0)
        {
            $auth = $password;
        }

        if (version_compare(phpversion('redis'), '6.0', '>='))
        {
            $options = [
                'host' => $host,
                'port' => $port,
                'connectTimeout' => $timeout,
                'persistent' => $persistent,
                'retryInterval' => $retryInterval,
                'readTimeout' => $readTimeout,
            ];

            if ($auth !== null)
            {
                $options['auth'] = $auth;
            }

            if (version_compare(phpversion('redis'), '6.1', '>=') && $ssl !== null)
            {
                $options['ssl'] = $ssl;
            }

            return new RedisSentinel($options);
        }

        if ($auth !== null)
        {
            /** @noinspection PhpMethodParametersCountMismatchInspection */
            return new RedisSentinel($host, $port, $timeout, $persistent, $retryInterval, $readTimeout, $auth);
        }

        return new RedisSentinel($host, $port, $timeout, $persistent, $retryInterval, $readTimeout);
    }
}