<?php
namespace App\Http\Controllers;

use App\Models\Stock;
use App\Models\StockLog;
use App\Models\ErpSku;
use App\Services\StockService;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;

class StockController extends Controller
{
    protected $stockService;

    public function __construct(StockService $stockService)
    {
        $this->stockService = $stockService;
    }

    /**
     * 库存列表（分页，支持搜索、仓库筛选、预警筛选）
     */
    public function index(Request $request)
    {
        $query = Stock::with(['warehouse', 'sku']);

        if ($request->filled('sku_code')) {
            $query->where('sku_code', 'like', "%{$request->sku_code}%");
        }
        if ($request->filled('warehouse_id')) {
            $query->where('warehouse_id', $request->warehouse_id);
        }
        if ($request->boolean('low_stock')) {
            $query->whereRaw('quantity - locked_quantity <= warning_threshold');
        }
        if ($request->filled('sku_name')) {
            $query->where('sku_name', 'like', "%{$request->sku_name}%");
        }

        $perPage = $request->input('limit', 15);
        $stocks = $query->orderBy('updated_at', 'desc')->paginate($perPage);

        // 格式化可用库存
        $stocks->getCollection()->transform(function ($stock) {
            return [
                'id' => $stock->id,
                'sku_code' => $stock->sku_code,
                'sku_name' => $stock->sku_name,
                'warehouse_id' => $stock->warehouse_id,
                'warehouse_name' => $stock->warehouse->name ?? null,
                'quantity' => $stock->quantity,
                'locked_quantity' => $stock->locked_quantity,
                'available_quantity' => $stock->available_quantity,
                'defective_quantity' => $stock->defective_quantity,
                'warning_threshold' => $stock->warning_threshold,
                'is_low' => $stock->available_quantity <= $stock->warning_threshold,
                'created_at' => $stock->created_at,
                'updated_at' => $stock->updated_at,
            ];
        });

        return response()->json([
            'code' => 200,
            'data' => [
                'list' => $stocks->items(),
                'total' => $stocks->total(),
                'current_page' => $stocks->currentPage(),
                'last_page' => $stocks->lastPage(),
            ],
            'message' => 'success'
        ]);
    }

    /**
     * 库存详情（按仓库+SKU）
     */
    public function show(Request $request)
    {
        $request->validate([
            'sku_code' => 'required|string',
            'warehouse_id' => 'required|exists:warehouses,id',
        ]);

        $stock = Stock::where('sku_code', $request->sku_code)
            ->where('warehouse_id', $request->warehouse_id)
            ->with(['warehouse', 'sku'])
            ->first();

        if (!$stock) {
            return response()->json(['code' => 404, 'message' => '库存记录不存在'], 404);
        }

        return response()->json([
            'code' => 200,
            'data' => [
                'sku_code' => $stock->sku_code,
                'sku_name' => $stock->sku_name,
                'warehouse_id' => $stock->warehouse_id,
                'warehouse_name' => $stock->warehouse->name,
                'quantity' => $stock->quantity,
                'locked_quantity' => $stock->locked_quantity,
                'available_quantity' => $stock->available_quantity,
                'defective_quantity' => $stock->defective_quantity,
                'warning_threshold' => $stock->warning_threshold,
            ],
            'message' => 'success'
        ]);
    }

    /**
     * 库存流水列表
     */
    public function logs(Request $request)
    {
        $query = StockLog::with(['warehouse', 'order']);

        if ($request->filled('sku_code')) {
            $query->where('sku_code', $request->sku_code);
        }
        if ($request->filled('warehouse_id')) {
            $query->where('warehouse_id', $request->warehouse_id);
        }
        if ($request->filled('type')) {
            $query->where('type', $request->type);
        }
        if ($request->filled('order_id')) {
            $query->where('order_id', $request->order_id);
        }
        if ($request->filled('delivery_no')) {
            $query->where('delivery_no', 'like', "%{$request->delivery_no}%");
        }
        if ($request->filled('start_date')) {
            $query->where('created_at', '>=', $request->start_date);
        }
        if ($request->filled('end_date')) {
            $query->where('created_at', '<=', $request->end_date . ' 23:59:59');
        }

        $perPage = $request->input('limit', 15);
        $logs = $query->orderBy('created_at', 'desc')->paginate($perPage);

        $logs->getCollection()->transform(function ($log) {
            return [
                'id' => $log->id,
                'sku_code' => $log->sku_code,
                'warehouse_id' => $log->warehouse_id,
                'warehouse_name' => $log->warehouse->name ?? null,
                'change_quantity' => $log->change_quantity,
                'type' => $log->type,
                'type_label' => $this->getTypeLabel($log->type),
                'related_no' => $log->related_no,
                'order_id' => $log->order_id,
                'order_short_id' => $log->order->short_id ?? null,
                'delivery_no' => $log->delivery_no,
                'remark' => $log->remark,
                'created_at' => $log->created_at,
            ];
        });

        return response()->json([
            'code' => 200,
            'data' => [
                'list' => $logs->items(),
                'total' => $logs->total(),
                'current_page' => $logs->currentPage(),
                'last_page' => $logs->lastPage(),
            ],
            'message' => 'success'
        ]);
    }

    private function getTypeLabel($type)
    {
        $map = [
            'inbound' => '入库',
            'outbound' => '出库',
            'lock' => '占用',
            'unlock' => '释放占用',
            'ship' => '发货出库',
            'defective_inbound' => '残次品入库',
            'adjust' => '手动调整',
        ];
        return $map[$type] ?? $type;
    }

    /**
     * 更新库存预警阈值
     */
    public function updateThreshold(Request $request)
    {
        $request->validate([
            'sku_code' => 'required|string',
            'warehouse_id' => 'required|exists:warehouses,id',
            'warning_threshold' => 'required|integer|min:0',
        ]);

        $stock = Stock::firstOrCreate(
            [
                'sku_code' => $request->sku_code,
                'warehouse_id' => $request->warehouse_id,
            ],
            [
                'sku_name' => $this->getSkuName($request->sku_code),
                'quantity' => 0,
                'locked_quantity' => 0,
                'defective_quantity' => 0,
            ]
        );

        $stock->warning_threshold = $request->warning_threshold;
        $stock->save();

        return response()->json([
            'code' => 200,
            'data' => $stock,
            'message' => '更新成功'
        ]);
    }

    private function getSkuName($skuCode)
    {
        $sku = ErpSku::where('sku_code', $skuCode)->first();
        return $sku ? $sku->name : '未知商品';
    }

    /**
     * 手动入库
     */
    public function manualInbound(Request $request)
    {
        $request->validate([
            'sku_code' => 'required|string',
            'warehouse_id' => 'required|exists:warehouses,id',
            'quantity' => 'required|integer|min:1',
            'remark' => 'nullable|string',
            'related_no' => 'nullable|string',
        ]);

        try {
            $stock = $this->stockService->inbound(
                $request->sku_code,
                $request->warehouse_id,
                $request->quantity,
                $request->related_no,
                $request->remark
            );

            return response()->json([
                'code' => 200,
                'data' => [
                    'sku_code' => $stock->sku_code,
                    'warehouse_id' => $stock->warehouse_id,
                    'quantity' => $stock->quantity,
                    'locked_quantity' => $stock->locked_quantity,
                    'available_quantity' => $stock->available_quantity,
                ],
                'message' => '入库成功'
            ]);
        } catch (\Exception $e) {
            return response()->json(['code' => 500, 'message' => $e->getMessage()], 500);
        }
    }

    /**
     * 手动出库
     */
    public function manualOutbound(Request $request)
    {
        $request->validate([
            'sku_code' => 'required|string',
            'warehouse_id' => 'required|exists:warehouses,id',
            'quantity' => 'required|integer|min:1',
            'remark' => 'nullable|string',
            'related_no' => 'nullable|string',
        ]);

        try {
            $stock = $this->stockService->outbound(
                $request->sku_code,
                $request->warehouse_id,
                $request->quantity,
                $request->related_no,
                $request->remark
            );

            return response()->json([
                'code' => 200,
                'data' => [
                    'sku_code' => $stock->sku_code,
                    'warehouse_id' => $stock->warehouse_id,
                    'quantity' => $stock->quantity,
                    'locked_quantity' => $stock->locked_quantity,
                    'available_quantity' => $stock->available_quantity,
                ],
                'message' => '出库成功'
            ]);
        } catch (\Exception $e) {
            return response()->json(['code' => 500, 'message' => $e->getMessage()], 500);
        }
    }

    /**
     * 残次品入库
     */
    public function defectiveInbound(Request $request)
    {
        $request->validate([
            'sku_code' => 'required|string',
            'warehouse_id' => 'required|exists:warehouses,id',
            'quantity' => 'required|integer|min:1',
            'remark' => 'nullable|string',
            'order_id' => 'nullable|exists:orders,id',
            'related_no' => 'nullable|string',
        ]);

        try {
            $stock = $this->stockService->defectiveInbound(
                $request->sku_code,
                $request->warehouse_id,
                $request->quantity,
                $request->related_no,
                $request->remark,
                $request->order_id
            );

            return response()->json([
                'code' => 200,
                'message' => '残次品入库成功'
            ]);
        } catch (\Exception $e) {
            return response()->json(['code' => 500, 'message' => $e->getMessage()], 500);
        }
    }

    /**
     * 手动调整库存（盘点校准）
     */
    public function adjust(Request $request)
    {
        $request->validate([
            'sku_code' => 'required|string',
            'warehouse_id' => 'required|exists:warehouses,id',
            'quantity' => 'nullable|integer|min:0',
            'locked_quantity' => 'nullable|integer|min:0',
            'defective_quantity' => 'nullable|integer|min:0',
            'remark' => 'nullable|string',
        ]);

        try {
            $stock = $this->stockService->adjust(
                $request->sku_code,
                $request->warehouse_id,
                $request->quantity,
                $request->locked_quantity,
                $request->defective_quantity,
                $request->remark
            );

            return response()->json([
                'code' => 200,
                'data' => [
                    'quantity' => $stock->quantity,
                    'locked_quantity' => $stock->locked_quantity,
                    'defective_quantity' => $stock->defective_quantity,
                ],
                'message' => '调整成功'
            ]);
        } catch (\Exception $e) {
            return response()->json(['code' => 500, 'message' => $e->getMessage()], 500);
        }
    }
}