<?php

namespace App\Services\LlmPrediction;

use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Log;

class GeminiPredictionProvider extends AbstractLlmPredictionProvider
{
    protected function apiKey(): ?string
    {
        return config('services.gemini.api_key');
    }

    protected function callProvider(string $apiKey, string $priceList): ?array
    {
        $model = config('services.gemini.model', 'gemini-2.0-flash');
        $url = "https://generativelanguage.googleapis.com/v1beta/models/{$model}:generateContent";

        $response = $this->apiLogger->send('gemini', 'POST', $url, fn () => Http::timeout(15)
            ->withQueryParameters(['key' => $apiKey])
            ->post($url, [
                'contents' => [[
                    'parts' => [['text' => $this->defaultPrompt($priceList)]],
                ]],
                'generationConfig' => [
                    'responseMimeType' => 'application/json',
                    'responseSchema' => [
                        'type' => 'OBJECT',
                        'properties' => [
                            'direction' => [
                                'type' => 'STRING',
                                'enum' => ['rising', 'falling', 'flat'],
                            ],
                            'confidence' => ['type' => 'INTEGER'],
                            'reasoning' => ['type' => 'STRING'],
                        ],
                        'required' => ['direction', 'confidence', 'reasoning'],
                    ],
                ],
            ]));

        if (! $response->successful()) {
            Log::error(self::class.': request failed', ['status' => $response->status()]);

            return null;
        }

        $text = $response->json('candidates.0.content.parts.0.text') ?? '';
        $data = json_decode($text, true);

        if (! isset($data['direction'], $data['confidence'], $data['reasoning'])) {
            Log::error(self::class.': unexpected response format', ['text' => $text]);

            return null;
        }

        return $data;
    }
}