<?php
// +----------------------------------------------------------------------
// | Niucloud-admin 企业快速开发的多应用管理平台
// +----------------------------------------------------------------------
// | 官方网址：https://www.niucloud.com
// +----------------------------------------------------------------------
// | niucloud团队 版权所有 开源版本可自由商用
// +----------------------------------------------------------------------
// | Author: Niucloud Team
// +----------------------------------------------------------------------

namespace app\service\admin\upload;

use app\service\core\sys\CoreConfigService;
use core\base\BaseAdminService;
use core\exception\AdminException;

/**
 * 对象存储直传服务类
 */
class DirectUploadService extends BaseAdminService
{
    /**
     * 获取上传凭证
     * @param string $file_type 文件类型
     * @param string $file_name 文件名
     * @return array
     */
    public function getUploadCredentials($file_type = 'image', $file_name = '')
    {
        // 获取存储配置
        $config_data = (new CoreConfigService())->getConfig('STORAGE');
        if (empty($config_data) || empty($config_data['value'])) {
            throw new AdminException('存储配置未设置');
        }
        
        $storage_config = $config_data['value'];
        if (is_string($storage_config)) {
            $storage_config = json_decode($storage_config, true);
        }
        
        if (empty($storage_config)) {
            throw new AdminException('存储配置格式错误');
        }
        
        $default_storage = $storage_config['default'] ?? 'local';
        if ($default_storage == 'local') {
            throw new AdminException('本地存储不支持直传');
        }
        
        if (!isset($storage_config[$default_storage])) {
            throw new AdminException('存储配置错误');
        }
        
        $config = $storage_config[$default_storage];
        
        // 生成文件路径
        $file_path = $this->generateFilePath($file_type, $file_name);
        
        // 根据不同存储类型获取凭证
        switch ($default_storage) {
            case 'tencent':
                return $this->getTencentCredentials($config, $file_path, $file_type);
            case 'aliyun':
                return $this->getAliyunCredentials($config, $file_path, $file_type);
            default:
                throw new AdminException('不支持的存储类型');
        }
    }
    
    /**
     * 获取腾讯云COS直传凭证
     * @param array $config 配置信息
     * @param string $file_path 文件路径
     * @param string $file_type 文件类型
     * @return array
     */
    private function getTencentCredentials($config, $file_path, $file_type)
    {
        // 检查必要的配置
        $required_keys = ['bucket', 'region', 'access_key', 'secret_key'];
        foreach ($required_keys as $key) {
            if (empty($config[$key])) {
                throw new AdminException("腾讯云配置缺少必要参数: {$key}");
            }
        }
        
        // 生成策略
        $expired = time() + 3600; // 1小时过期
        $policy = [
            'expiration' => gmdate('Y-m-d\TH:i:s.000\Z', $expired),
            'conditions' => [
                ['bucket' => $config['bucket']],
                ['starts-with' => '$key', $file_path]
            ]
        ];
        
        // 根据文件类型设置大小限制
        $max_size = $this->getMaxFileSize($file_type);
        if ($max_size > 0) {
            $policy['conditions'][] = ['content-length-range', 0, $max_size];
        }
        
        $policy_encoded = base64_encode(json_encode($policy));
        $signature = hash_hmac('sha1', $policy_encoded, $config['secret_key'], true);
        $signature_encoded = base64_encode($signature);
        
        return [
            'storage_type' => 'tencent',
            'upload_url' => "https://{$config['bucket']}.cos.{$config['region']}.myqcloud.com",
            'credentials' => [
                'policy' => $policy_encoded,
                'q-sign-algorithm' => 'sha1',
                'q-ak' => $config['access_key'],
                'q-key-time' => time() . ';' . $expired,
                'q-signature' => $signature_encoded,
            ],
            'file_path' => $file_path,
            'domain' => $config['domain'] ?? "https://{$config['bucket']}.cos.{$config['region']}.myqcloud.com",
            'max_size' => $max_size,
            'expired' => $expired
        ];
    }
    
    /**
     * 获取阿里云OSS直传凭证
     * @param array $config 配置信息
     * @param string $file_path 文件路径
     * @param string $file_type 文件类型
     * @return array
     */
    private function getAliyunCredentials($config, $file_path, $file_type)
    {
        // 检查必要的配置
        $required_keys = ['bucket', 'endpoint', 'access_key', 'secret_key'];
        foreach ($required_keys as $key) {
            if (empty($config[$key])) {
                throw new AdminException("阿里云配置缺少必要参数: {$key}");
            }
        }
        
        $expired = time() + 3600; // 1小时过期
        $dir = dirname($file_path) . '/';
        
        // 生成策略
        $policy = [
            'expiration' => gmdate('Y-m-d\TH:i:s.000\Z', $expired),
            'conditions' => [
                ['starts-with' => '$key', $dir],
            ]
        ];
        
        // 根据文件类型设置大小限制
        $max_size = $this->getMaxFileSize($file_type);
        if ($max_size > 0) {
            $policy['conditions'][] = ['content-length-range', 0, $max_size];
        }
        
        $policy_encoded = base64_encode(json_encode($policy));
        $signature = base64_encode(hash_hmac('sha1', $policy_encoded, $config['secret_key'], true));
        
        return [
            'storage_type' => 'aliyun',
            'upload_url' => "https://{$config['bucket']}.{$config['endpoint']}",
            'credentials' => [
                'OSSAccessKeyId' => $config['access_key'],
                'policy' => $policy_encoded,
                'signature' => $signature,
                'key' => $file_path,
                'success_action_status' => '200',
            ],
            'file_path' => $file_path,
            'domain' => $config['domain'] ?? "https://{$config['bucket']}.{$config['endpoint']}",
            'max_size' => $max_size,
            'expired' => $expired
        ];
    }
    
    /**
     * 生成文件路径
     * @param string $file_type 文件类型
     * @param string $file_name 文件名
     * @return string
     */
    private function generateFilePath($file_type, $file_name = '')
    {
        $type_dir_map = [
            'image' => 'upload/attachment/image',
            'video' => 'upload/attachment/video', 
            'document' => 'upload/attachment/document'
        ];
        
        $dir = $type_dir_map[$file_type] ?? 'upload/attachment/file';
        $date_dir = date('Y/m/d');
        
        if (empty($file_name)) {
            $file_name = uniqid() . '_${filename}'; // ${filename} 将被前端替换
        }
        
        return $dir . '/' . $date_dir . '/' . $file_name;
    }
    
    /**
     * 根据文件类型获取最大文件大小
     * @param string $file_type 文件类型
     * @return int 字节数，0表示不限制
     */
    private function getMaxFileSize($file_type)
    {
        $size_map = [
            'image' => 10 * 1024 * 1024,   // 10MB
            'video' => 500 * 1024 * 1024,  // 500MB  
            'document' => 50 * 1024 * 1024, // 50MB
        ];
        
        return $size_map[$file_type] ?? 10 * 1024 * 1024;
    }
    
    /**
     * 确认上传完成
     * @param array $data 文件信息
     * @return array
     */
    public function confirmUpload($data)
    {
        // 这里可以将文件信息保存到附件表，供后续管理使用
        // 暂时直接返回文件URL，实际项目中可以根据需要保存到数据库
        
        return [
            'url' => $data['file_url'],
            'name' => $data['file_name'],
            'size' => $data['file_size'],
            'type' => $data['file_type'],
            'storage_type' => $data['storage_type']
        ];
    }
}