<?php

declare(strict_types=1);

namespace App\Services;

use App\Models\AiModel;
use App\Models\AiProvider;
use App\Services\Ai\AiServiceFactory;
use Illuminate\Http\Client\ConnectionException;
use Illuminate\Support\Facades\Log;
use RuntimeException;

class ChatService
{
    private const SESSION_KEY = 'chat_conversation';

    public function __construct(
        private readonly AiServiceFactory $aiServiceFactory
    ) {}

    /**
     * Get conversation history from session.
     *
     * @return array<int, array{role: string, content: string}>
     */
    public function getHistory(): array
    {
        return session()->get(self::SESSION_KEY, []);
    }

    /**
     * Reset conversation history.
     */
    public function reset(): void
    {
        session()->forget(self::SESSION_KEY);
    }

    /**
     * Send a message and get AI response.
     *
     * @return array<string, mixed>
     */
    public function sendMessage(
        string $userMessage,
        AiProvider $provider,
        AiModel $model,
        float $temperature = 0.7,
        int $maxTokens = 8192
    ): array {
        $history = $this->getHistory();

        $history[] = ['role' => 'user', 'content' => $userMessage];

        $startTime = microtime(true);

        try {
            $service = $this->aiServiceFactory->make($provider);
            $result = $service->chat($history, [
                'temperature' => $temperature,
                'max_tokens' => $maxTokens,
                'model' => $model->slug,
                'api_key' => $provider->api_key,
                'base_url' => $provider->base_url,
            ]);
        } catch (ConnectionException|RuntimeException $e) {
            Log::error('Chat API error: ' . $e->getMessage());

            return [
                'success' => false,
                'error' => $e->getMessage(),
                'content' => '',
                'role' => 'assistant',
                'tokens_used' => null,
                'generation_time' => round(microtime(true) - $startTime, 3),
            ];
        }

        $assistantMessage = [
            'role' => 'assistant',
            'content' => $result['content'] ?? '',
        ];

        $history[] = $assistantMessage;

        session()->put(self::SESSION_KEY, $history);

        return [
            'success' => true,
            'content' => $result['content'] ?? '',
            'role' => 'assistant',
            'tokens_used' => $result['tokens_used'] ?? null,
            'generation_time' => round(microtime(true) - $startTime, 3),
        ];
    }
}