<?php

namespace App\Services;

use App\Support\Settings;
use Illuminate\Support\Facades\Http;

/**
 * Generic OpenAI-compatible chat-completions client — works against Groq,
 * OpenAI itself, or a self-hosted Ollama instance's OpenAI-compat endpoint,
 * whichever the admin points ai_base_url at. Not BookStack-specific; the
 * BookStack content tagger is just the first consumer.
 */
class AiClient
{
    public function enabled(): bool
    {
        // Deliberately no api-key requirement here — a self-hosted Ollama
        // instance typically has no auth at all.
        return Settings::bool('ai_enabled')
            && Settings::get('ai_base_url')
            && Settings::get('ai_model');
    }

    /**
     * @param  array<int, array{role: string, content: string}>  $messages
     * @return string|null the assistant message content, or null on any failure
     */
    public function chat(array $messages, array $options = []): ?string
    {
        if (! $this->enabled()) {
            return null;
        }

        try {
            $response = $this->client()->post('/chat/completions', [
                'model' => Settings::get('ai_model'),
                'messages' => $messages,
                ...$options,
            ]);

            if (! $response->successful()) {
                return null;
            }

            return $response->json('choices.0.message.content');
        } catch (\Throwable) {
            return null;
        }
    }

    /**
     * Tests unsaved admin-form values directly, rather than whatever's
     * currently stored — mirrors BookStackClient::testConnection().
     *
     * @return array{ok: bool, message: ?string}
     */
    public function testConnection(string $baseUrl, string $apiKey, string $model, bool $verifySsl = true): array
    {
        try {
            $http = Http::withOptions(['verify' => $verifySsl])
                ->timeout(10)
                ->baseUrl(rtrim($baseUrl, '/'));

            if ($apiKey !== '') {
                $http = $http->withToken($apiKey);
            }

            $response = $http->post('/chat/completions', [
                'model' => $model,
                'messages' => [['role' => 'user', 'content' => 'ping']],
                'max_tokens' => 1,
            ]);

            if ($response->successful()) {
                return ['ok' => true, 'message' => null];
            }

            return ['ok' => false, 'message' => $response->json('error.message') ?? ('HTTP '.$response->status())];
        } catch (\Throwable $e) {
            return ['ok' => false, 'message' => $e->getMessage()];
        }
    }

    protected function client()
    {
        $http = Http::withOptions(['verify' => Settings::bool('ai_verify_ssl')])
            ->timeout(60)
            ->baseUrl(rtrim(Settings::get('ai_base_url'), '/'));

        $apiKey = Settings::get('ai_api_key');

        return $apiKey ? $http->withToken($apiKey) : $http;
    }
}