<?php

namespace App\Modules\Inventory\Controllers;

use App\Http\Controllers\Controller;

use App\Modules\Inventory\Models\Unit;
use App\Modules\Inventory\Models\Product; // Import Product to check for usage
use Illuminate\Http\Request;

class UnitController extends Controller
{
    /**
     * Store a newly created resource in storage.
     */
    public function store(Request $request)
    {
        $validated = $request->validate([
            'name' => 'required|string|max:255|unique:units,name',
            'code' => 'nullable|string|max:50',
        ], [
            'name.required' => '單位名稱為必填項目',
            'name.unique' => '該單位名稱已存在',
            'name.max' => '單位名稱不能超過 255 個字元',
            'code.max' => '單位代碼不能超過 50 個字元',
        ]);

        Unit::create($validated);

        return redirect()->back()->with('success', '單位已建立');
    }

    /**
     * Update the specified resource in storage.
     */
    public function update(Request $request, Unit $unit)
    {
        $validated = $request->validate([
            'name' => 'required|string|max:255|unique:units,name,' . $unit->id,
            'code' => 'nullable|string|max:50',
        ], [
            'name.required' => '單位名稱為必填項目',
            'name.unique' => '該單位名稱已存在',
            'name.max' => '單位名稱不能超過 255 個字元',
            'code.max' => '單位代碼不能超過 50 個字元',
        ]);

        $unit->update($validated);

        return redirect()->back()->with('success', '單位已更新');
    }

    /**
     * Remove the specified resource from storage.
     */
    public function destroy(Unit $unit)
    {
        // Check if unit is used in any product
        $isUsed = Product::where('base_unit_id', $unit->id)
            ->orWhere('large_unit_id', $unit->id)
            ->orWhere('purchase_unit_id', $unit->id)
            ->exists();

        if ($isUsed) {
            return redirect()->back()->with('error', '該單位已被商品使用，無法刪除');
        }

        $unit->delete();

        return redirect()->back()->with('success', '單位已刪除');
    }
}