<?php

namespace App\Services;

use App\Models\ClassPackageUnit;
use App\Models\ClassPackageUnitVariation;
use Illuminate\Database\Eloquent\Collection;

class ClassPackageUnitVariationService
{
    public function getAll(int $packageUnitId, int $unitId): Collection
    {
        return ClassPackageUnitVariation::with('products.product')
            ->whereHas('classPackageUnit', fn ($query) => $query->where('unit_id', $unitId))
            ->where('class_package_unit_id', $packageUnitId)
            ->get();
    }

    public function findById(int $id, int $packageUnitId, int $unitId): ClassPackageUnitVariation
    {
        return ClassPackageUnitVariation::with('products.product')
            ->whereHas('classPackageUnit', fn ($query) => $query->where('unit_id', $unitId))
            ->where('class_package_unit_id', $packageUnitId)
            ->findOrFail($id);
    }

    public function create(int $packageUnitId, int $unitId, array $data): ClassPackageUnitVariation
    {
        $packageUnit = ClassPackageUnit::with('products')
            ->where('unit_id', $unitId)
            ->findOrFail($packageUnitId);

        // sem lista propria a proposta herda os materiais do pacote da unidade

        $materials = $data['materials'] ?? $this->unitMaterials($packageUnit);
        unset($data['materials']);

        // o valor do material nao e editavel, ele acompanha a lista

        $data['material_value'] = $this->calcMaterialValue($materials);
        $data['class_package_unit_id'] = $packageUnit->id;

        $variation = ClassPackageUnitVariation::create($data);

        $this->syncProducts($variation, $materials);

        return $variation->load('products.product');
    }

    public function update(int $id, int $packageUnitId, int $unitId, array $data): ClassPackageUnitVariation
    {
        $variation = $this->findById($id, $packageUnitId, $unitId);

        $materials = $data['materials'] ?? null;
        unset($data['materials']);

        if ($materials !== null) {
            $data['material_value'] = $this->calcMaterialValue($materials);
        }

        $variation->update($data);

        if ($materials !== null) {
            $this->syncProducts($variation, $materials);
        }

        return $variation->fresh('products.product');
    }

    public function delete(int $id, int $packageUnitId, int $unitId): bool
    {
        $variation = $this->findById($id, $packageUnitId, $unitId);

        return $variation->delete();
    }

    // Add custom business logic methods here

    private function calcMaterialValue(array $materials): float
    {
        return array_reduce($materials, fn ($carry, $material) => $carry + ($material['quantity'] * $material['price']), 0.0);
    }

    private function syncProducts(ClassPackageUnitVariation $variation, array $materials): void
    {
        $variation->products()->delete();

        foreach ($materials as $material) {
            $variation->products()->create([
                'product_id' => $material['product_id'],
                'quantity'   => $material['quantity'],
                'price'      => $material['price'],
            ]);
        }
    }

    private function unitMaterials(ClassPackageUnit $packageUnit): array
    {
        return $packageUnit->products
            ->map(fn ($product) => [
                'product_id' => $product->product_id,
                'quantity'   => $product->quantity,
                'price'      => (float) $product->price,
            ])
            ->all();
    }
}