<?php

declare(strict_types=1);

namespace App\Http\Controllers\Api;

use App\Constants\ErrorCode;
use App\Http\Controllers\Controller;
use App\Services\LlmService;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Log;
use Illuminate\Validation\ValidationException;

class LlmController extends Controller
{
    /**
     * @var LlmService
     */
    private readonly LlmService $llmService;

    public function __construct(LlmService $llmService)
    {
        $this->llmService = $llmService;
    }

    /**
     * 發送 LLM 請求
     *
     * @param Request $request
     * @return JsonResponse
     * @throws ValidationException|\RuntimeException
     */
    public function request(Request $request): JsonResponse
    {
        try {
            if (!$request->client) {
                throw new \RuntimeException('客戶信息未找到。');
            }

            /** @var array{
             *     prompt: string,
             *     max_tokens?: int,
             *     temperature?: float,
             *     top_p?: float,
             *     frequency_penalty?: float,
             *     presence_penalty?: float
             * } $validated */
            $validated = $request->validate([
                'prompt' => 'required|string|max:4000',
                'max_tokens' => 'nullable|integer|min:1|max:4000',
                'temperature' => 'nullable|numeric|min:0|max:2',
                'top_p' => 'nullable|numeric|min:0|max:1',
                'frequency_penalty' => 'nullable|numeric|min:-2|max:2',
                'presence_penalty' => 'nullable|numeric|min:-2|max:2',
            ]);

            /** @var array{response: string} $result */
            $result = $this->llmService->sendRequest(
                $request->client,
                $validated['prompt'],
                array_filter($validated, fn($key) => $key !== 'prompt', ARRAY_FILTER_USE_KEY)
            );

            if (!isset($result['response'])) {
                throw new \RuntimeException('LLM 提供商返回的響應格式無效。');
            }

            return $this->success([
                'response' => $result['response'],
            ]);

        } catch (ValidationException $e) {
            return $this->error(
                ErrorCode::VALIDATION_ERROR,
                ErrorCode::getMessage(ErrorCode::VALIDATION_ERROR),
                $e->errors()
            );
        } catch (\InvalidArgumentException $e) {
            return $this->error(
                ErrorCode::INVALID_REQUEST_FORMAT,
                $e->getMessage()
            );
        } catch (\RuntimeException $e) {
            return $this->error(
                ErrorCode::PROVIDER_ERROR,
                $e->getMessage()
            );
        } catch (\Exception $e) {
            Log::error('Error processing LLM request', [
                'error' => $e->getMessage(),
                'trace' => $e->getTraceAsString(),
                'client_id' => $request->client->id,
                'request_data' => $request->except(['prompt']),
            ]);

            return $this->error(
                ErrorCode::SERVER_ERROR,
                ErrorCode::getMessage(ErrorCode::SERVER_ERROR)
            );
        }
    }
}