<?php

declare(strict_types=1);

namespace App\Services\Ai;

use App\Models\AiProvider;
use GuzzleHttp\Client;
use GuzzleHttp\Exception\GuzzleException;
use Illuminate\Support\Facades\Log;

class OpenRouterService implements AiServiceInterface
{
    /**
     * @param AiProvider $provider
     */
    public function __construct(private AiProvider $provider)
    {
        $this->client = new Client([
            'base_uri' => rtrim((string) $provider->base_url, '/') . '/',
            'timeout' => 120,
        ]);
    }

    public function chat(array $messages, array $data = []): array
    {
        $apiKey = $data['api_key'] ?? $this->provider->api_key;

        if (empty($apiKey)) {
            throw new \InvalidArgumentException('OpenRouter API key is not configured.');
        }

        try {
            $response = $this->client->post('chat/completions', [
                'headers' => [
                    'Authorization' => 'Bearer ' . $apiKey,
                    'Content-Type' => 'application/json',
                    'HTTP-Referer' => $data['http_referer'] ?? config('app.url'),
                    'X-Title' => $data['x_title'] ?? config('app.name'),
                ],
                'json' => [
                    'model' => (string) ($data['model'] ?? ''),
                    'messages' => $messages,
                    'temperature' => isset($data['temperature']) ? (float) $data['temperature'] : null,
                    'max_tokens' => isset($data['max_tokens']) ? (int) $data['max_tokens'] : null,
                ],
            ]);

            $body = json_decode($response->getBody()->getContents(), true);

            if (!isset($body['choices'][0]['message']['content'])) {
                throw new \RuntimeException('Invalid response structure from OpenRouter.');
            }

            return [
                'content' => $body['choices'][0]['message']['content'],
                'tokens_used' => $body['usage']['total_tokens'] ?? null,
                'model' => $body['model'] ?? (string) ($data['model'] ?? ''),
            ];
        } catch (GuzzleException $e) {
            Log::error('OpenRouter API error: ' . $e->getMessage());
            throw new \RuntimeException('Failed to generate prompt with OpenRouter: ' . $e->getMessage(), (int) $e->getCode(), $e);
        }
    }

    /**
     * {@inheritdoc}
     */
    public function generatePrompt(array $data): array
    {
        return $this->chat(
            [['role' => 'user', 'content' => (string) ($data['prompt'] ?? '')]],
            $data
        );
    }
}