Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

namespace aiprovider_azureai;

use core\http_client;

use core_ai\ai_image;

use GuzzleHttp\Psr7\Request;

use GuzzleHttp\Psr7\Uri;

use Psr\Http\Message\RequestInterface;

use Psr\Http\Message\ResponseInterface;

use Psr\Http\Message\UriInterface;

/**

 * Class process image generation.

 *

 * @package    aiprovider_azureai

 * @copyright  2024 Matt Porritt <matt.porritt@moodle.com>

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class process_generate_image extends abstract_processor {

    /** @var int The number of images to generate dall-e-3 only supports 1 */

    private int $numberimages = 1;

    #[\Override]

    protected function get_endpoint(): UriInterface {

        $url = rtrim($this->provider->config['endpoint'], '/')

            . '/openai/deployments/'

            . $this->get_deployment_name()

            . '/images/generations?api-version='

            . $this->get_api_version();

        return new Uri($url);

    }

    #[\Override]

    protected function query_ai_api(): array {

        $response = parent::query_ai_api();

        // If the request was successful, save the URL to a file.

        if ($response['success']) {

            $fileobj = $this->url_to_file(

                $this->action->get_configuration('userid'),

                $response['sourceurl']

            );

            // Add the file to the response, so the calling placement can do whatever they want with it.

            $response['draftfile'] = $fileobj;

        }

        return $response;

    }

    /**

     * Convert the given aspect ratio to an image size

     * that is compatible with the azureai API.

     *

     * @param string $ratio The aspect ratio of the image.

     * @return string The size of the image.

     * @throws \coding_exception

     */

    private function calculate_size(string $ratio): string {

        if ($ratio === 'square') {

            $size = '1024x1024';

        } else if ($ratio === 'landscape') {

            $size = '1792x1024';

        } else if ($ratio === 'portrait') {

            $size = '1024x1792';

        } else {

            throw new \coding_exception('Invalid aspect ratio: ' . $ratio);

        }

        return $size;

    }

    #[\Override]

    protected function create_request_object(string $userid): RequestInterface {

        return new Request(

            method: 'POST',

            uri: '',

            headers: [

                'Content-Type' => 'application/json',

            ],

            body: json_encode((object) [

                'prompt' => $this->action->get_configuration('prompttext'),

                'n' => $this->numberimages,

                'quality' => $this->action->get_configuration('quality'),

                'size' => $this->calculate_size($this->action->get_configuration('aspectratio')),

                'style' => $this->action->get_configuration('style'),

                'user' => $userid,

            ]),

        );

    }

    #[\Override]

    protected function handle_api_success(ResponseInterface $response): array {

        $responsebody = $response->getBody();

        $bodyobj = json_decode($responsebody->getContents());

        return [

            'success' => true,

            'sourceurl' => $bodyobj->data[0]->url,

            'revisedprompt' => $bodyobj->data[0]->revised_prompt,

        ];

    }

    /**

     * Convert the url for the image  to a file.

     *

     * Placements can't interact with the provider AI directly,

     * therefore we need to provide the image file in a format that can

     * be used by placements. So we use the file API.

     *

     * @param int $userid The user id.

     * @param string $url The URL to the image.

     * @return \stored_file The file object.

     */

    private function url_to_file(int $userid, string $url): \stored_file {

        global $CFG;

        require_once("{$CFG->libdir}/filelib.php");

        // Azure AI doesn't always return unique file names, but does return unique URLS.

        // Therefore, some processing is needed to get a unique filename.

        $parsedurl = parse_url($url, PHP_URL_PATH); // Parse the URL to get the path.

        $fileext = pathinfo($parsedurl, PATHINFO_EXTENSION); // Get the file extension.

        $filename = substr(hash('sha512', ($url . $userid)), 0, 16) . '.' . $fileext;

        $client = \core\di::get(http_client::class);

        // Download the image and add the watermark.

        $downloadtmpdir = make_request_directory();

        $tempdst = $downloadtmpdir . $filename;

        $client->get($url, [

            'sink' => $tempdst,

            'timeout' => $CFG->repositorygetfiletimeout,

        ]);

        $image = new ai_image($tempdst);

        $image->add_watermark()->save();

        // We put the file in the user draft area initially.

        // Placements (on behalf of the user) can then move it to the correct location.

        $fileinfo = new \stdClass();

        $fileinfo->contextid = \context_user::instance($userid)->id;

        $fileinfo->filearea = 'draft';

        $fileinfo->component = 'user';

        $fileinfo->itemid = file_get_unused_draft_itemid();

        $fileinfo->filepath = '/';

        $fileinfo->filename = $filename;

        $fs = get_file_storage();

        return $fs->create_file_from_string($fileinfo, file_get_contents($tempdst));

    }

}