<?php
namespace app\common\library;

use think\Config;
use think\Exception;
use think\File;
use GuzzleHttp\Client;
use GuzzleHttp\Psr7\Request;

class AwsS3
{
    protected $config;
    protected $client;
    protected $bucket;
    protected $region;

    public function __construct()
    {
        $this->config = Config::get('aws.s3');
        $this->bucket = $this->config['bucket'];
        $this->region = $this->config['region'];
        $this->client = new Client([
            'timeout' => 30,
            'verify' => false, // 根据环境调整
        ]);
    }

    /**
     * 生成 AWS S4 签名
     */
    protected function generateSignature($method, $uri, $headers, $payload = '')
    {
        $accessKey = $this->config['credentials']['key'];
        $secretKey = $this->config['credentials']['secret'];

        $service = 's3';
        $algorithm = 'AWS4-HMAC-SHA256';

        // 当前时间
        $timestamp = time();
        $longDate = gmdate('Ymd\THis\Z', $timestamp);
        $shortDate = substr($longDate, 0, 8);

        // 计算签名所需组件
        $scope = $shortDate . '/' . $this->region . '/' . $service . '/aws4_request';

        // 规范化请求
        $canonicalHeaders = '';
        $signedHeaders = '';

        ksort($headers);
        foreach ($headers as $key => $value) {
            $canonicalHeaders .= strtolower($key) . ':' . trim($value) . "\n";
            $signedHeaders .= strtolower($key) . ';';
        }
        $signedHeaders = rtrim($signedHeaders, ';');

        $canonicalRequest = implode("\n", [
            $method,
            $uri,
            '', // 查询字符串
            $canonicalHeaders,
            $signedHeaders,
            hash('sha256', $payload)
        ]);

        // 计算签名
        $stringToSign = implode("\n", [
            $algorithm,
            $longDate,
            $scope,
            hash('sha256', $canonicalRequest)
        ]);

        // 派生签名密钥
        $kDate = hash_hmac('sha256', $shortDate, 'AWS4' . $secretKey, true);
        $kRegion = hash_hmac('sha256', $this->region, $kDate, true);
        $kService = hash_hmac('sha256', $service, $kRegion, true);
        $kSigning = hash_hmac('sha256', 'aws4_request', $kService, true);

        $signature = hash_hmac('sha256', $stringToSign, $kSigning);

        return $algorithm . ' ' . implode(', ', [
                'Credential=' . $accessKey . '/' . $scope,
                'SignedHeaders=' . $signedHeaders,
                'Signature=' . $signature
            ]);
    }

    /**
     * 上传文件到 S3
     */
    public function upload($file, $key = null, $options = [],$website)
    {
        $link ='https://cdn.alipearlhair.com';
        if($website=='alipearlhair'){
            $this->bucket ='alipearl-images';
            $link ='https://cdn.alipearlhair.com';
        }
        if($website=='wigginshair'){
            $this->bucket ='wiggins-images';
            $link ='https://cdn.wigginshair.com';
        }
        try {
            // 处理文件
            if ($file instanceof File) {
                $filePath = $file->getRealPath();
                $fileContent = file_get_contents($filePath);
                $mimeType = $file->getMime();
            } elseif (is_string($file) && file_exists($file)) {
                $fileContent = file_get_contents($file);
                $mimeType = mime_content_type($file);
            } else {
                $fileContent = $file;
                $mimeType = $options['mime_type'] ?? 'application/octet-stream';
            }

            // 生成存储 key
            if (empty($key)) {
                $key = $this->generateKey($file);
            }
            // 准备请求
            $method = 'PUT';
            $uri = '/' . $key;
            $url = 'https://' . $this->bucket . '.s3.' . $this->region . '.amazonaws.com' . $uri;
            $urls = $link . $uri;
            $headers = [
                'Host' => $this->bucket . '.s3.' . $this->region . '.amazonaws.com',
                'Content-Type' => $mimeType,
                'Content-Length' => strlen($fileContent),
                'x-amz-content-sha256' => hash('sha256', $fileContent),
                'x-amz-date' => gmdate('Ymd\THis\Z'),

            ];

            // 添加额外头部
            if (!empty($options['headers'])) {
                $headers = array_merge($headers, $options['headers']);
            }

            // 生成签名
            $headers['Authorization'] = $this->generateSignature($method, $uri, $headers, $fileContent);

            // 发送请求
            $response = $this->client->request($method, $url, [
                'headers' => $headers,
                'body' => $fileContent,
            ]);

            if ($response->getStatusCode() == 200) {
                return [
                    'success' => true,
                    'key'     => $key,
                    'url'     => $urls,
                    'size'    => strlen($fileContent),
                    'type'    => $mimeType
                ];
            } else {
                throw new Exception('上传失败，状态码: ' . $response->getStatusCode());
            }

        } catch (\Exception $e) {
            return [
                'success' => false,
                'msg'     => '上传失败: ' . $e->getMessage(),
                'error'   => $e->getMessage()
            ];
        }
    }

    /**
     * 生成存储路径 key
     */
    protected function generateKey($file)
    {
        $config = $this->config['upload'];
        $savePath = $config['save_path'];

        // 替换路径变量
        $replace = [
            '{year}'     => date('Y'),
            '{mon}'      => date('m'),
            '{day}'      => date('d'),
            '{hour}'     => date('H'),
            '{min}'      => date('i'),
            '{sec}'      => date('s'),
            '{random}'   => mt_rand(1000, 9999),
            '{uniqid}'   => uniqid(),
            '{timestamp}'=> time(),
        ];

        $savePath = str_replace(array_keys($replace), array_values($replace), $savePath);

        // 生成文件名
        // 获取原始文件名和扩展名
        $originalName = $file->getInfo('name'); // 原始文件名，如 "image.jpg"
        $originalExtension = pathinfo($originalName, PATHINFO_EXTENSION);

// 如果原始扩展名有效，使用它
        if (!empty($originalExtension) && strlen($originalExtension) <= 6) {
            $extension = strtolower($originalExtension);
        } else {
            // 否则通过内容检测
            $extension = $this->getRealExtensionByContent($file->getRealPath());
        }
        $sha1 = sha1($file);
        $filename = date('YmdHis') . '_' . substr($sha1, 0, 16) . '.' . $extension;
        return $savePath . $filename;
    }

    /**
     * 删除 S3 文件
     */
    public function delete($key)
    {
        try {
            $method = 'DELETE';
            $uri = '/' . $key;
            $url = 'https://' . $this->bucket . '.s3.' . $this->region . '.amazonaws.com' . $uri;

            $headers = [
                'Host' => $this->bucket . '.s3.' . $this->region . '.amazonaws.com',
                'x-amz-date' => gmdate('Ymd\THis\Z'),
                'x-amz-content-sha256' => hash('sha256', ''),
            ];

            $headers['Authorization'] = $this->generateSignature($method, $uri, $headers);

            $response = $this->client->request($method, $url, [
                'headers' => $headers,
            ]);

            return $response->getStatusCode() == 204;

        } catch (\Exception $e) {
            return false;
        }
    }

    /**
     * 检查文件是否存在
     */
    public function exists($key)
    {
        try {
            $method = 'HEAD';
            $uri = '/' . $key;
            $url = 'https://' . $this->bucket . '.s3.' . $this->region . '.amazonaws.com' . $uri;

            $headers = [
                'Host' => $this->bucket . '.s3.' . $this->region . '.amazonaws.com',
                'x-amz-date' => gmdate('Ymd\THis\Z'),
                'x-amz-content-sha256' => hash('sha256', ''),
            ];

            $headers['Authorization'] = $this->generateSignature($method, $uri, $headers);

            $response = $this->client->request($method, $url, [
                'headers' => $headers,
            ]);

            return $response->getStatusCode() == 200;

        } catch (\Exception $e) {
            return false;
        }
    }

    /**
     * 获取文件 URL
     */
    public function getUrl($key, $expires = 3600)
    {
        if ($expires === null) {
            // 公开读取的直接 URL
            $cdnUrl = rtrim($this->config['upload']['cdn_url'], '/');
            return $cdnUrl . '/' . $key;
        } else {
            // 生成预签名 URL
            return $this->generatePresignedUrl($key, $expires);
        }
    }

    /**
     * 生成预签名 URL
     */
    protected function generatePresignedUrl($key, $expires = 3600)
    {
        $accessKey = $this->config['credentials']['key'];
        $secretKey = $this->config['credentials']['secret'];

        $timestamp = time();
        $expiresAt = $timestamp + $expires;
        $longDate = gmdate('Ymd\THis\Z', $timestamp);
        $shortDate = substr($longDate, 0, 8);

        $service = 's3';
        $algorithm = 'AWS4-HMAC-SHA256';
        $scope = $shortDate . '/' . $this->region . '/' . $service . '/aws4_request';

        // 生成签名
        $canonicalQueryString = implode('&', [
            'X-Amz-Algorithm=AWS4-HMAC-SHA256',
            'X-Amz-Credential=' . urlencode($accessKey . '/' . $scope),
            'X-Amz-Date=' . $longDate,
            'X-Amz-Expires=' . $expires,
            'X-Amz-SignedHeaders=host'
        ]);

        $canonicalRequest = implode("\n", [
            'GET',
            '/' . $key,
            $canonicalQueryString,
            'host:' . $this->bucket . '.s3.' . $this->region . '.amazonaws.com',
            '',
            'host',
            'UNSIGNED-PAYLOAD'
        ]);

        $stringToSign = implode("\n", [
            $algorithm,
            $longDate,
            $scope,
            hash('sha256', $canonicalRequest)
        ]);

        // 派生签名密钥
        $kDate = hash_hmac('sha256', $shortDate, 'AWS4' . $secretKey, true);
        $kRegion = hash_hmac('sha256', $this->region, $kDate, true);
        $kService = hash_hmac('sha256', $service, $kRegion, true);
        $kSigning = hash_hmac('sha256', 'aws4_request', $kService, true);

        $signature = hash_hmac('sha256', $stringToSign, $kSigning);

        $url = sprintf(
            'https://%s.s3.%s.amazonaws.com/%s?%s&X-Amz-Signature=%s',
            $this->bucket,
            $this->region,
            $key,
            $canonicalQueryString,
            $signature
        );

        return $url;
    }
}