<?php

namespace App\Services\Admin\Manage;

use App\Enums\PriceType;
use App\Enums\ProductStockQuality;
use App\Models\Product;
use App\Models\ProductVariant;
use App\Models\Restock;
use App\Models\RestockItem;
use App\Services\Concerns\RegistersMedia;
use App\Services\NotificationService;
use App\Services\S3PresignedService;
use Illuminate\Contracts\Pagination\LengthAwarePaginator;
use Illuminate\Support\Facades\DB;

class RestockService
{
    use RegistersMedia;

    private const QUALITY_STOCK_MAP = [
        ProductStockQuality::GOOD->value => 'stock',
        ProductStockQuality::REJECT->value => 'reject_stock',
    ];

    public function __construct(
        private S3PresignedService $s3Service = new S3PresignedService,
    ) {}

    public function paginated(int $perPage = 25, string $search = '', string $sort = 'created_at', string $direction = 'desc'): LengthAwarePaginator
    {
        $paginator = Restock::query()
            ->select('id', 'created_by_id', 'subtotal', 'total', 'notes', 'stock_type', 'created_at')
            ->with([
                'createdBy:id',
                'createdBy.userProfile:id,user_id,full_name',
                'restockItems:id,restock_id,product_variant_id,quantity,unit_price,subtotal',
                'restockItems.productVariant:id,product_id,name,stock,reject_stock,retail_stock',
                'restockItems.productVariant.product:id,name',
            ])
            ->when($search, function ($q) use ($search) {
                $q->whereHas('restockItems.productVariant.product', fn ($sq) => $sq->where('name', 'like', "%{$search}%"))
                    ->orWhere('notes', 'like', "%{$search}%");
            })
            ->orderBy($sort, $direction)
            ->paginate($perPage);

        $paginator->getCollection()->each(function (Restock $restock) {
            $restock->restockItems->each(function (RestockItem $item) {
                if (! $item->productVariant) {
                    return;
                }

                $media = $item->productVariant->getFirstMedia('photos');
                $item->productVariant->photo_url = $media
                    ? $this->s3Service->getTemporaryUrl($media->file_name)
                    : null;
            });
        });

        return $paginator;
    }

    public function getForCreate(): array
    {
        return [
            'products' => Product::query()
                ->select('id', 'name', 'status')
                ->with([
                    'productVariants:id,product_id,name,stock,reject_stock',
                    'productVariants.productPrices:id,variant_id,type,price',
                ])
                ->orderBy('name')
                ->get()
                ->each(function (Product $product) {
                    $product->productVariants->each(function (ProductVariant $variant) {
                        $media = $variant->getFirstMedia('photos');
                        $variant->photo_url = $media
                            ? $this->s3Service->getTemporaryUrl($media->file_name)
                            : null;

                        $capitalPrice = $variant->productPrices
                            ->first(fn ($price) => $price->type === PriceType::CAPITAL);
                        $variant->capital_price = $capitalPrice?->price ?? 0;
                    });
                }),
        ];
    }

    public function getForEdit(Restock $restock): array
    {
        $restock->load('restockItems.productVariant.product');

        $media = $restock->getFirstMedia('photos');

        return [
            'id' => $restock->id,
            'stock_type' => $restock->stock_type->value,
            'notes' => $restock->notes,
            'photo_key' => $media?->file_name,
            'photo_url' => $media
                ? $this->s3Service->getTemporaryUrl($media->file_name)
                : null,
            'items' => $restock->restockItems->map(fn (RestockItem $item) => [
                'id' => $item->id,
                'product_variant_id' => $item->product_variant_id,
                'quantity' => $item->quantity,
                'unit_price' => $item->unit_price,
            ])->values(),
        ];
    }

    public function create(array $data): Restock
    {
        return DB::transaction(function () use ($data) {
            $now = now();
            $subtotal = 0;
            $stockType = $data['stock_type'] ?? ProductStockQuality::GOOD->value;

            $itemRows = $this->buildItemRows($data['items'], $now, $subtotal);

            $restock = Restock::create([
                'created_by_id' => auth()->id(),
                'subtotal' => $subtotal,
                'total' => $subtotal,
                'notes' => $data['notes'] ?? null,
                'stock_type' => $stockType,
            ]);

            foreach ($itemRows as &$row) {
                $row['restock_id'] = $restock->id;
            }
            DB::table('restock_items')->insert($itemRows);

            $this->applyStock($data['items'], $stockType, 1);
            $this->syncPhoto($restock, $data);

            NotificationService::notify(
                roles: ['Owner', 'Developer', 'Admin Toko'],
                title: 'Restock Baru',
                body: 'Restock '.($stockType === ProductStockQuality::GOOD->value ? 'produk' : 'reject').' sebesar Rp '.number_format($subtotal, 0, ',', '.').' berhasil dicatat oleh '.auth()->user()->full_name.'.',
                url: route('admin.manage.restocks.index'),
            );

            return $restock;
        });
    }

    public function update(Restock $restock, array $data): Restock
    {
        return DB::transaction(function () use ($restock, $data) {
            $restock->load('restockItems');

            $restock->restockItems->each(function (RestockItem $item) use ($restock) {
                $this->adjustVariantStock($item->product_variant_id, $item->quantity, -1, $restock->stock_type->value);
            });

            $restock->restockItems()->delete();

            $now = now();
            $subtotal = 0;
            $stockType = $data['stock_type'] ?? $restock->stock_type->value;

            $itemRows = $this->buildItemRows($data['items'], $now, $subtotal);

            foreach ($itemRows as &$row) {
                $row['restock_id'] = $restock->id;
            }
            DB::table('restock_items')->insert($itemRows);

            $restock->update([
                'subtotal' => $subtotal,
                'total' => $subtotal,
                'notes' => $data['notes'] ?? null,
                'stock_type' => $stockType,
            ]);

            $this->applyStock($data['items'], $stockType, 1);
            $this->syncPhoto($restock, $data);

            return $restock;
        });
    }

    public function delete(Restock $restock): bool
    {
        return DB::transaction(function () use ($restock) {
            $restock->load('restockItems');

            $restock->restockItems->each(function (RestockItem $item) use ($restock) {
                $this->adjustVariantStock($item->product_variant_id, $item->quantity, -1, $restock->stock_type->value);
            });

            $restock->restockItems()->delete();
            $restock->clearMediaCollection('photos');
            $restock->delete();

            return true;
        });
    }

    private function buildItemRows(array $items, $now, int &$subtotal): array
    {
        $variantIds = collect($items)->pluck('product_variant_id')->unique()->all();
        $capitalPrices = ProductVariant::query()
            ->whereKey($variantIds)
            ->with('productPrices:id,variant_id,type,price')
            ->get()
            ->mapWithKeys(function (ProductVariant $variant) {
                $capitalPrice = $variant->productPrices
                    ->first(fn ($price) => $price->type === PriceType::CAPITAL);

                return [$variant->id => $capitalPrice?->price ?? 0];
            });

        return collect($items)->map(function ($item) use ($now, $capitalPrices, &$subtotal) {
            $quantity = (int) $item['quantity'];
            $unitPrice = (int) ($capitalPrices[$item['product_variant_id']] ?? 0);
            $itemSubtotal = $unitPrice * $quantity;
            $subtotal += $itemSubtotal;

            return [
                'restock_id' => null,
                'user_id' => auth()->id(),
                'product_variant_id' => $item['product_variant_id'],
                'quantity' => $quantity,
                'unit_price' => $unitPrice,
                'subtotal' => $itemSubtotal,
                'created_at' => $now,
                'updated_at' => $now,
            ];
        })->toArray();
    }

    private function applyStock(array $items, string $stockType, int $sign): void
    {
        foreach ($items as $item) {
            $this->adjustVariantStock($item['product_variant_id'], $item['quantity'], $sign, $stockType);
        }
    }

    private function adjustVariantStock(int $variantId, int $quantity, int $sign, string $stockType): void
    {
        $field = self::QUALITY_STOCK_MAP[$stockType] ?? 'stock';

        if ($sign > 0) {
            ProductVariant::whereKey($variantId)->increment($field, $quantity);
        } else {
            ProductVariant::whereKey($variantId)->decrement($field, $quantity);
        }
    }

    private function syncPhoto(Restock $restock, array $data): void
    {
        if (! array_key_exists('photo_key', $data)) {
            return;
        }

        $currentKey = $restock->getFirstMedia('photos')?->file_name;

        if ($data['photo_key'] === $currentKey) {
            return;
        }

        $restock->clearMediaCollection('photos');

        if (! empty($data['photo_key'])) {
            $this->registerMedia(
                model: $restock,
                s3Key: $data['photo_key'],
                collectionName: 'photos',
                orderColumn: 1,
            );
        }
    }
}