<?php
/**
 * Copyright (C) Alibaba Cloud Computing
 * All rights reserved.
 *
 * 版权所有 （C）阿里云计算有限公司
 */
namespace Aliyun\OSS\Auth;

use Aliyun\OSS\Utilities\OSSHeaders;

use Aliyun\Common\Communication\HttpRequest;

use Aliyun\Common\Auth\ServiceSignature;

use Aliyun\OSS\Utilities\SignUtils;

use Aliyun\OSS\Models\OSSOptions;

use Aliyun\Common\Utilities\AssertUtils;

use Aliyun\Common\Auth\SignerInterface;

class OSSRequestSigner implements SignerInterface {

    private $bucket;

    private $key;

    function __construct($bucket, $key) {
        $this->bucket = $bucket;
        $this->key = $key;
    }

    public function sign(HttpRequest $request, array $credentials) {
	    AssertUtils::assertSet(array(
                    OSSOptions::ACCESS_KEY_ID,
                    OSSOptions::ACCESS_KEY_SECRET,
	    ), $credentials);
	    AssertUtils::assertString($credentials[OSSOptions::ACCESS_KEY_ID], OSSOptions::ACCESS_KEY_ID);
	    AssertUtils::assertString($credentials[OSSOptions::ACCESS_KEY_SECRET], OSSOptions::ACCESS_KEY_SECRET);
		
	    $key = $credentials[OSSOptions::ACCESS_KEY_ID];
	    $secret = $credentials[OSSOptions::ACCESS_KEY_SECRET];
	    
	    if (strlen($key) > 0 && strlen($secret) > 0) {
	        $canonicalString = SignUtils::buildCanonicalString($request, $this->bucket, $this->key);
	        $signature = ServiceSignature::factory()->computeSignature($secret, $canonicalString);
	        
	        $request->addHeader(OSSHeaders::AUTHORIZATION, 'OSS '.$key.':'.$signature);
	    } else if (strlen($key) > 0) {
	        $request->addHeader(OSSHeaders::AUTHORIZATION, $key);
	    }
	}
}