<?php
declare(strict_types=1);

namespace GamesShop\Api;

use Curl\Curl;
use Exception;
use GamesShop\Environment\EnvironmentHandler;
use GamesShop\Errors\ExtendedException;

final class DiscordAPI
{
    const string OAUTH_TOKEN_URL = "https://discord.com/api/oauth2/token";
    const string USER_ME_URL = 'https://discord.com/api/users/@me';

    public function __construct(
        private readonly EnvironmentHandler $env
    )
    {
    }

    /**
     * @return array{id: string, global_name: string, avatar: string, discriminator: int}
     * @throws Exception
     */
    public function getUserFromCode(string $code, string $redirectUri): array {
        $discordEnv = $this->env->getDiscordEnvironment();

        $curl = new Curl();
        $curl->setHeader('Content-Type', 'application/x-www-form-urlencoded');
        $curl->setBasicAuthentication($discordEnv->clientId, $discordEnv->clientSecret);

        $data =[
            'grant_type' => 'authorization_code',
            'code' => $code,
            'redirect_uri' => $redirectUri
        ];
        $curl->post(self::OAUTH_TOKEN_URL, $data);

        if ($curl->error) {
            $curl->diagnose();

            throw new ExtendedException($curl->errorMessage, [ 'response' => $curl->response, 'data' => $data ]);
        }

        $accessToken = $curl->response->access_token;
        $tokenType = $curl->response->token_type;

        $curl = new Curl();
        $curl->setHeader("authorization", "$tokenType $accessToken");
        $curl->get(self::USER_ME_URL);

        if ($curl->error) {
            $curl->diagnose();

            throw new ExtendedException($curl->errorMessage, [ 'response' => $curl->response, ]);
        }

        return [
            'id' => $curl->response->id,
            'global_name' => $curl->response->global_name,
            'avatar' => $curl->response->avatar,
            'discriminator' => (int) $curl->response->discriminator
        ];
    }

    public function getAvatarURL(string $userId, string|int $avatarHash) {
        if (is_int($avatarHash)) {
            return "https://cdn.discordapp.com/embed/avatars/{$avatarHash}.png";
        }

        $extension = 'png';
        if (str_starts_with($avatarHash, 'a_')) {
            $extension = 'gif';
        }

        return "https://cdn.discordapp.com/avatars/{$userId}/{$avatarHash}.{$extension}";
    }
}