<?php

declare(strict_types=1);

namespace App\Http\Controllers\Api;

use App\Http\Controllers\Controller;
use App\Http\Requests\StorePurchaseOrderRequest;
use App\Http\Requests\UpdatePurchaseOrderRequest;
use App\Http\Resources\Fournisseur\PurchaseOrderResource;
use App\Models\GoodsReceipt;
use App\Models\Warehouse;
use App\Repositories\GoodsReceiptRepositoryInterface;
use App\Repositories\PurchaseOrderRepositoryInterface;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Resources\Json\AnonymousResourceCollection;
use Illuminate\Support\Facades\Log;

class PurchaseOrderController extends Controller
{
    public function __construct(
        protected PurchaseOrderRepositoryInterface $purchaseOrderRepository,
        protected GoodsReceiptRepositoryInterface $goodsReceiptRepository
    ) {
    }

    /**
     * Display a listing of purchase orders.
     */
    public function index(): AnonymousResourceCollection|JsonResponse
    {
        try {
            $purchaseOrders = $this->purchaseOrderRepository->all();
            return PurchaseOrderResource::collection($purchaseOrders);
        } catch (\Exception $e) {
            Log::error('Error fetching purchase orders: ' . $e->getMessage(), [
                'exception' => $e,
                'trace' => $e->getTraceAsString(),
            ]);

            return response()->json([
                'message' => 'Une erreur est survenue lors de la récupération des commandes fournisseurs.',
                'error' => config('app.debug') ? $e->getMessage() : null,
            ], 500);
        }
    }

    /**
     * Store a newly created purchase order.
     */
    public function store(StorePurchaseOrderRequest $request): PurchaseOrderResource|JsonResponse
    {
        try {
            $purchaseOrder = $this->purchaseOrderRepository->create($request->validated());
            return new PurchaseOrderResource($purchaseOrder);
        } catch (\Exception $e) {
            Log::error('Error creating purchase order: ' . $e->getMessage(), [
                'exception' => $e,
                'trace' => $e->getTraceAsString(),
                'data' => $request->validated(),
            ]);

            return response()->json([
                'message' => 'Une erreur est survenue lors de la création de la commande fournisseur.',
                'error' => config('app.debug') ? $e->getMessage() : null,
            ], 500);
        }
    }

    /**
     * Display the specified purchase order.
     */
    public function show(string $id): PurchaseOrderResource|JsonResponse
    {
        try {
            $purchaseOrder = $this->purchaseOrderRepository->find($id);

            if (!$purchaseOrder) {
                return response()->json([
                    'message' => 'Commande fournisseur non trouvée.',
                ], 404);
            }

            return new PurchaseOrderResource($purchaseOrder);
        } catch (\Exception $e) {
            Log::error('Error fetching purchase order: ' . $e->getMessage(), [
                'exception' => $e,
                'trace' => $e->getTraceAsString(),
                'purchase_order_id' => $id,
            ]);

            return response()->json([
                'message' => 'Une erreur est survenue lors de la récupération de la commande fournisseur.',
                'error' => config('app.debug') ? $e->getMessage() : null,
            ], 500);
        }
    }

    /**
     * Update the specified purchase order.
     */
    public function update(UpdatePurchaseOrderRequest $request, string $id): PurchaseOrderResource|JsonResponse
    {
        try {
            $existingPurchaseOrder = $this->purchaseOrderRepository->find($id);
            $previousStatus = $existingPurchaseOrder?->status;

            $updated = $this->purchaseOrderRepository->update($id, $request->validated());

            if (!$updated) {
                return response()->json([
                    'message' => 'Commande fournisseur non trouvée ou échec de la mise à jour.',
                ], 404);
            }

            $purchaseOrder = $this->purchaseOrderRepository->find($id);

            // On validation/delivery (status => confirmee|livree), create a draft goods receipt automatically.
            if (
                $purchaseOrder
                && in_array($purchaseOrder->status, ['confirmee', 'livree'], true)
                && !in_array($previousStatus, ['confirmee', 'livree'], true)
            ) {
                $this->createGoodsReceiptFromValidatedPurchaseOrder($purchaseOrder);
            }

            return new PurchaseOrderResource($purchaseOrder);
        } catch (\Exception $e) {
            Log::error('Error updating purchase order: ' . $e->getMessage(), [
                'exception' => $e,
                'trace' => $e->getTraceAsString(),
                'purchase_order_id' => $id,
                'data' => $request->validated(),
            ]);

            return response()->json([
                'message' => 'Une erreur est survenue lors de la mise à jour de la commande fournisseur.',
                'error' => config('app.debug') ? $e->getMessage() : null,
            ], 500);
        }
    }

    /**
     * Create a draft goods receipt when a purchase order is validated.
     */
    protected function createGoodsReceiptFromValidatedPurchaseOrder($purchaseOrder): void
    {
        $alreadyExists = GoodsReceipt::query()
            ->where('purchase_order_id', $purchaseOrder->id)
            ->exists();

        if ($alreadyExists) {
            return;
        }

        $warehouseId = Warehouse::query()->value('id');
        if (!$warehouseId) {
            throw new \RuntimeException('Aucun entrepôt disponible pour créer la réception de marchandise.');
        }

        $receiptNumber = 'GR-' . now()->format('Ym') . '-' . str_pad((string) $purchaseOrder->id, 4, '0', STR_PAD_LEFT);

        $lines = collect($purchaseOrder->lines ?? [])
            ->filter(fn($line) => !empty($line->product_id))
            ->map(function ($line) {
                return [
                    'product_id' => (int) $line->product_id,
                    'packaging_id' => null,
                    'packages_qty_received' => null,
                    'units_qty_received' => (float) $line->quantity,
                    'qty_received_base' => (float) $line->quantity,
                    'unit_price' => (float) $line->unit_price,
                    'unit_price_per_package' => null,
                    'tva_rate_id' => null,
                ];
            })
            ->values()
            ->all();

        $this->goodsReceiptRepository->create([
            'purchase_order_id' => $purchaseOrder->id,
            'warehouse_id' => (int) $warehouseId,
            'receipt_number' => $receiptNumber,
            'receipt_date' => now()->toDateString(),
            'status' => 'draft',
            'lines' => $lines,
        ]);
    }

    /**
     * Remove the specified purchase order.
     */
    public function destroy(string $id): JsonResponse
    {
        try {
            $deleted = $this->purchaseOrderRepository->delete($id);

            if (!$deleted) {
                return response()->json([
                    'message' => 'Commande fournisseur non trouvée ou échec de la suppression.',
                ], 404);
            }

            return response()->json([
                'message' => 'Commande fournisseur supprimée avec succès.',
            ], 200);
        } catch (\Exception $e) {
            Log::error('Error deleting purchase order: ' . $e->getMessage(), [
                'exception' => $e,
                'trace' => $e->getTraceAsString(),
                'purchase_order_id' => $id,
            ]);

            return response()->json([
                'message' => 'Une erreur est survenue lors de la suppression de la commande fournisseur.',
                'error' => config('app.debug') ? $e->getMessage() : null,
            ], 500);
        }
    }
}