<?php

namespace App\Services;

use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\Http;

class LlmModelCatalogService
{
    public function modelsFor(array $instance, bool $refresh = false): array
    {
        $cacheKey = 'llm_models_'.sha1(json_encode([
            'type' => $instance['type'] ?? '',
            'base_url' => $instance['base_url'] ?? '',
        ]));

        if ($refresh) {
            Cache::forget($cacheKey);
        }

        return Cache::remember($cacheKey, now()->addMinutes(5), fn () => $this->fetchModels($instance));
    }

    public function cachedUntil(array $instance): ?string
    {
        $models = $this->modelsFor($instance);

        return $models === [] ? null : now()->addMinutes(5)->format('H:i:s');
    }

    private function fetchModels(array $instance): array
    {
        $type = (string) ($instance['type'] ?? '');
        $baseUrl = rtrim((string) ($instance['base_url'] ?? ''), '/');

        if ($baseUrl === '') {
            return [];
        }

        return match ($type) {
            'lmstudio' => $this->fetchLmStudioModels($baseUrl),
            'ollama' => $this->fetchOllamaModels($baseUrl),
            default => [],
        };
    }

    private function fetchLmStudioModels(string $baseUrl): array
    {
        $response = Http::connectTimeout(2)
            ->timeout(5)
            ->get($baseUrl.'/v1/models')
            ->throw()
            ->json();

        return collect($response['data'] ?? [])
            ->pluck('id')
            ->filter()
            ->map(fn ($model) => (string) $model)
            ->unique()
            ->sort()
            ->values()
            ->all();
    }

    private function fetchOllamaModels(string $baseUrl): array
    {
        $response = Http::connectTimeout(2)
            ->timeout(5)
            ->get($baseUrl.'/api/tags')
            ->throw()
            ->json();

        return collect($response['models'] ?? [])
            ->map(fn ($model) => (string) ($model['name'] ?? $model['model'] ?? ''))
            ->filter()
            ->unique()
            ->sort()
            ->values()
            ->all();
    }
}