<?php

namespace WP_Media_Folder\Aws\S3;

use WP_Media_Folder\Aws\Credentials\CredentialsInterface;
use WP_Media_Folder\GuzzleHttp\Psr7\Uri;
use WP_Media_Folder\Aws\Signature\SignatureTrait;
use WP_Media_Folder\Aws\Signature\SignatureV4;
use WP_Media_Folder\Aws\Api\TimestampShape;
/**
 * Encapsulates the logic for getting the data for an S3 object POST upload form
 *
 * @link http://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectPOST.html
 * @link http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-post-example.html
 */
class PostObjectV4
{
    use SignatureTrait;
    private $client;
    private $bucket;
    private $formAttributes;
    private $formInputs;
    /**
     * Constructs the PostObject.
     *
     * The options array accepts the following keys:
     * @link http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-query-string-auth.html
     *
     * @param S3ClientInterface $client     Client used with the POST object
     * @param string            $bucket     Bucket to use
     * @param array             $formInputs Associative array of form input
     *                                      fields.
     * @param array             $options    Policy condition options
     * @param mixed             $expiration Upload expiration time value. By
     *                                      default: 1 hour valid period.
     */
    public function __construct(\WP_Media_Folder\Aws\S3\S3ClientInterface $client, $bucket, array $formInputs, array $options = [], $expiration = '+1 hours')
    {
        $this->client = $client;
        $this->bucket = $bucket;
        // setup form attributes
        $this->formAttributes = ['action' => $this->generateUri(), 'method' => 'POST', 'enctype' => 'multipart/form-data'];
        $credentials = $this->client->getCredentials()->wait();
        if ($securityToken = $credentials->getSecurityToken()) {
            array_push($options, ['x-amz-security-token' => $securityToken]);
            $formInputs['X-Amz-Security-Token'] = $securityToken;
        }
        // setup basic policy
        $policy = ['expiration' => \WP_Media_Folder\Aws\Api\TimestampShape::format($expiration, 'iso8601'), 'conditions' => $options];
        // setup basic formInputs
        $this->formInputs = $formInputs + ['key' => '${filename}'];
        // finalize policy and signature
        $this->formInputs += $this->getPolicyAndSignature($credentials, $policy);
    }
    /**
     * Gets the S3 client.
     *
     * @return S3ClientInterface
     */
    public function getClient()
    {
        return $this->client;
    }
    /**
     * Gets the bucket name.
     *
     * @return string
     */
    public function getBucket()
    {
        return $this->bucket;
    }
    /**
     * Gets the form attributes as an array.
     *
     * @return array
     */
    public function getFormAttributes()
    {
        return $this->formAttributes;
    }
    /**
     * Set a form attribute.
     *
     * @param string $attribute Form attribute to set.
     * @param string $value     Value to set.
     */
    public function setFormAttribute($attribute, $value)
    {
        $this->formAttributes[$attribute] = $value;
    }
    /**
     * Gets the form inputs as an array.
     *
     * @return array
     */
    public function getFormInputs()
    {
        return $this->formInputs;
    }
    /**
     * Set a form input.
     *
     * @param string $field Field name to set
     * @param string $value Value to set.
     */
    public function setFormInput($field, $value)
    {
        $this->formInputs[$field] = $value;
    }
    private function generateUri()
    {
        $uri = new \WP_Media_Folder\GuzzleHttp\Psr7\Uri($this->client->getEndpoint());
        if ($this->client->getConfig('use_path_style_endpoint') === true || $uri->getScheme() === 'https' && strpos($this->bucket, '.') !== false) {
            // Use path-style URLs
            $uri = $uri->withPath("/{$this->bucket}");
        } else {
            // Use virtual-style URLs if haven't been set up already
            if (strpos($uri->getHost(), $this->bucket . '.') !== 0) {
                $uri = $uri->withHost($this->bucket . '.' . $uri->getHost());
            }
        }
        return (string) $uri;
    }
    protected function getPolicyAndSignature(\WP_Media_Folder\Aws\Credentials\CredentialsInterface $credentials, array $policy)
    {
        $ldt = gmdate(\WP_Media_Folder\Aws\Signature\SignatureV4::ISO8601_BASIC);
        $sdt = substr($ldt, 0, 8);
        $policy['conditions'][] = ['X-Amz-Date' => $ldt];
        $region = $this->client->getRegion();
        $scope = $this->createScope($sdt, $region, 's3');
        $creds = "{$credentials->getAccessKeyId()}/{$scope}";
        $policy['conditions'][] = ['X-Amz-Credential' => $creds];
        $policy['conditions'][] = ['X-Amz-Algorithm' => "AWS4-HMAC-SHA256"];
        $jsonPolicy64 = base64_encode(json_encode($policy));
        $key = $this->getSigningKey($sdt, $region, 's3', $credentials->getSecretKey());
        return ['X-Amz-Credential' => $creds, 'X-Amz-Algorithm' => "AWS4-HMAC-SHA256", 'X-Amz-Date' => $ldt, 'Policy' => $jsonPolicy64, 'X-Amz-Signature' => bin2hex(hash_hmac('sha256', $jsonPolicy64, $key, true))];
    }
}
