<?php

namespace App\Helpers;

use App\Models\System\AiTokenUsage;
use Illuminate\Support\Facades\Log;
use Illuminate\Support\Str;

class AiTokenHelper
{
    /**
     * Gemini API 응답에서 토큰 사용량 저장
     */
    public static function saveGeminiUsage(array $apiResult, string $model, string $menuName): void
    {
        try {
            $usage = $apiResult['usageMetadata'] ?? null;
            if (! $usage) {
                return;
            }

            $promptTokens = $usage['promptTokenCount'] ?? 0;
            $completionTokens = $usage['candidatesTokenCount'] ?? 0;
            $totalTokens = $usage['totalTokenCount'] ?? 0;

            // Gemini 2.0 Flash 기준 단가
            $inputPrice = 0.10 / 1_000_000;
            $outputPrice = 0.40 / 1_000_000;

            self::save($model, $menuName, $promptTokens, $completionTokens, $totalTokens, $inputPrice, $outputPrice);
        } catch (\Exception $e) {
            Log::warning('AI token usage save failed (Gemini)', ['error' => $e->getMessage()]);
        }
    }

    /**
     * Claude API 응답에서 토큰 사용량 저장
     */
    public static function saveClaudeUsage(array $apiResult, string $model, string $menuName): void
    {
        try {
            $usage = $apiResult['usage'] ?? null;
            if (! $usage) {
                return;
            }

            $promptTokens = $usage['input_tokens'] ?? 0;
            $completionTokens = $usage['output_tokens'] ?? 0;
            $totalTokens = $promptTokens + $completionTokens;

            // Claude 3 Haiku 기준 단가
            $inputPrice = 0.25 / 1_000_000;
            $outputPrice = 1.25 / 1_000_000;

            self::save($model, $menuName, $promptTokens, $completionTokens, $totalTokens, $inputPrice, $outputPrice);
        } catch (\Exception $e) {
            Log::warning('AI token usage save failed (Claude)', ['error' => $e->getMessage()]);
        }
    }

    /**
     * 공통 저장 로직
     */
    private static function save(
        string $model,
        string $menuName,
        int $promptTokens,
        int $completionTokens,
        int $totalTokens,
        float $inputPricePerToken,
        float $outputPricePerToken,
    ): void {
        $costUsd = ($promptTokens * $inputPricePerToken) + ($completionTokens * $outputPricePerToken);
        $exchangeRate = (float) config('services.gemini.exchange_rate', 1400);
        $costKrw = $costUsd * $exchangeRate;

        $tenantId = session('selected_tenant_id', 1);

        AiTokenUsage::create([
            'tenant_id' => $tenantId,
            'model' => $model,
            'menu_name' => $menuName,
            'prompt_tokens' => $promptTokens,
            'completion_tokens' => $completionTokens,
            'total_tokens' => $totalTokens,
            'cost_usd' => $costUsd,
            'cost_krw' => $costKrw,
            'request_id' => Str::uuid()->toString(),
            'created_by' => auth()->id(),
        ]);
    }
}