<?php

namespace App\Actions;

use App\Enums\NutritionPlanSource;
use App\Enums\WeeklyReviewStatus;
use App\Models\NutritionPlan;
use App\Models\WeeklyReview;
use Illuminate\Support\Facades\DB;

class AcceptWeeklyReviewAdjustment
{
    public function execute(WeeklyReview $weeklyReview): NutritionPlan
    {
        return DB::transaction(function () use ($weeklyReview): NutritionPlan {
            $lockedReview = WeeklyReview::query()->lockForUpdate()->findOrFail($weeklyReview->getKey());

            abort_if($lockedReview->accepted_at !== null, 409, 'WEEKLY_ADJUSTMENT_ALREADY_ACCEPTED');
            abort_unless(
                $lockedReview->status === WeeklyReviewStatus::ADJUSTMENT_RECOMMENDED
                    && $lockedReview->recommended_calorie_adjustment !== 0,
                409,
                'WEEKLY_ADJUSTMENT_UNAVAILABLE',
            );

            $user = $lockedReview->user()->lockForUpdate()->firstOrFail();
            $currentPlan = $user->nutritionPlans()->where('is_active', true)->latest('effective_from')->firstOrFail();

            abort_unless(
                $lockedReview->nutrition_plan_id === $currentPlan->getKey(),
                409,
                'WEEKLY_ADJUSTMENT_STALE',
            );

            $now = now();
            $targetCalories = max(1200, $currentPlan->calories + $lockedReview->recommended_calorie_adjustment);
            $proteins = (int) round($currentPlan->proteins);
            $fats = (int) round($currentPlan->fats);
            $carbs = max(0, (int) round(($targetCalories - ($proteins * 4) - ($fats * 9)) / 4));
            $calories = ($proteins * 4) + ($carbs * 4) + ($fats * 9);

            abort_if(
                $calories === $currentPlan->calories,
                409,
                'WEEKLY_ADJUSTMENT_UNAVAILABLE',
            );

            $currentPlan->update([
                'is_active' => false,
                'effective_until' => $now,
            ]);

            $nextPlan = $user->nutritionPlans()->create([
                'source' => NutritionPlanSource::WEEKLY_ADJUSTMENT,
                'formula_version' => $currentPlan->formula_version,
                'calories' => $calories,
                'proteins' => $proteins,
                'carbs' => $carbs,
                'fats' => $fats,
                'resting_metabolism' => $currentPlan->resting_metabolism,
                'maintenance_calories' => $currentPlan->maintenance_calories,
                'calorie_adjustment_percent' => ($calories - $currentPlan->maintenance_calories) / max(1, $currentPlan->maintenance_calories),
                'calculation_details' => [
                    ...$currentPlan->calculation_details,
                    'weeklyReviewId' => $lockedReview->getKey(),
                    'weeklyAdjustmentCalories' => $lockedReview->recommended_calorie_adjustment,
                ],
                'effective_from' => $now,
            ]);

            $lockedReview->update([
                'accepted_at' => $now,
                'accepted_nutrition_plan_id' => $nextPlan->getKey(),
            ]);

            return $nextPlan;
        }, attempts: 3);
    }
}