<?php

namespace App\Modules\Inventory\Controllers;

use App\Http\Controllers\Controller;

use Illuminate\Http\Request;

use App\Modules\Inventory\Models\Warehouse;

use Inertia\Inertia;

class WarehouseController extends Controller
{
    public function index(Request $request)
    {
        $query = Warehouse::query();

        if ($request->has('search')) {
            $search = $request->input('search');
            $query->where(function ($q) use ($search) {
                $q->where('name', 'like', "%{$search}%")
                  ->orWhere('code', 'like', "%{$search}%");
            });
        }

        $perPage = $request->input('per_page', 10);
        if (!in_array($perPage, [10, 20, 50, 100])) {
            $perPage = 10;
        }

        $warehouses = $query->withSum('inventories as book_stock', 'quantity') // 帳面庫存 = 所有庫存總和
            ->withSum(['inventories as available_stock' => function ($query) {
                // 可用庫存 = 庫存 > 0 且 品質正常 且 (未過期 或 無效期) 且 倉庫類型不為瑕疵倉
                $query->where('quantity', '>', 0)
                      ->where('quality_status', 'normal')
                      ->whereHas('warehouse', function ($q) {
                          $q->where('type', '!=', \App\Enums\WarehouseType::QUARANTINE);
                      })
                      ->where(function ($q) {
                          $q->whereNull('expiry_date')
                            ->orWhere('expiry_date', '>=', now());
                      });
            }], 'quantity')
            ->addSelect(['low_stock_count' => function ($query) {
                $query->selectRaw('count(*)')
                    ->from('warehouse_product_safety_stocks as ss')
                    ->whereColumn('ss.warehouse_id', 'warehouses.id')
                    ->whereRaw('(SELECT COALESCE(SUM(quantity), 0) FROM inventories WHERE warehouse_id = ss.warehouse_id AND product_id = ss.product_id) < ss.safety_stock');
            }])
            ->orderBy('created_at', 'desc')
            ->paginate($perPage)
            ->withQueryString();

        // 移除原本對 is_sellable 的手動修正邏輯，現在由 type 自動過濾


        // 計算全域總計 (不分頁)
        $totals = [
            'available_stock' => \App\Modules\Inventory\Models\Inventory::where('quantity', '>', 0)
                ->where('quality_status', 'normal')
                ->whereHas('warehouse', function ($q) {
                    $q->where('type', '!=', \App\Enums\WarehouseType::QUARANTINE);
                })
                ->where(function ($q) {
                    $q->whereNull('expiry_date')
                      ->orWhere('expiry_date', '>=', now());
                })->sum('quantity'),
            'book_stock' => \App\Modules\Inventory\Models\Inventory::sum('quantity'),
        ];

        return Inertia::render('Warehouse/Index', [
            'warehouses' => $warehouses,
            'totals' => $totals,
            'filters' => $request->only(['search', 'per_page']),
        ]);
    }

    public function store(Request $request)
    {
        $validated = $request->validate([
            'name' => 'required|string|max:50',
            'address' => 'nullable|string|max:255',
            'description' => 'nullable|string',
            'type' => 'required|string',
            'license_plate' => 'nullable|string|max:20',
            'driver_name' => 'nullable|string|max:50',
        ]);

        // 自動產生代碼
        $prefix = 'WH';
        $lastWarehouse = Warehouse::latest('id')->first();
        $nextId = $lastWarehouse ? $lastWarehouse->id + 1 : 1;
        $code = $prefix . str_pad($nextId, 3, '0', STR_PAD_LEFT);

        $validated['code'] = $code;

        Warehouse::create($validated);

        return redirect()->back()->with('success', '倉庫已建立');
    }

    public function update(Request $request, Warehouse $warehouse)
    {
        $validated = $request->validate([
            'name' => 'required|string|max:50',
            'address' => 'nullable|string|max:255',
            'description' => 'nullable|string',
            'type' => 'required|string',
            'license_plate' => 'nullable|string|max:20',
            'driver_name' => 'nullable|string|max:50',
        ]);

        $warehouse->update($validated);

        return redirect()->back()->with('success', '倉庫資訊已更新');
    }

    public function destroy(Warehouse $warehouse)
    {
        // 檢查是否有相關聯的採購單
        if ($warehouse->purchaseOrders()->exists()) {
            return redirect()->back()->with('error', '無法刪除：該倉庫有相關聯的採購單，請先處理採購單。');
        }

        \Illuminate\Support\Facades\DB::transaction(function () use ($warehouse) {
            // 刪除庫存異動紀錄 (透過庫存關聯)
            foreach ($warehouse->inventories as $inventory) {
                // 刪除該庫存的所有異動紀錄
                $inventory->transactions()->delete();
            }
            
            // 刪除庫存項目
            $warehouse->inventories()->delete();

            // 刪除倉庫
            $warehouse->delete();
        });

        return redirect()->back()->with('success', '倉庫及其庫存與紀錄已刪除');
    }
}