<?php

namespace App\Http\Controllers;

use App\Models\Employee;
use App\Models\StockMovement;
use App\Models\StockVariant;
use App\Models\UniformIssue;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
use Illuminate\Validation\ValidationException;

class IssueController extends Controller
{
    public function index()
    {
        return view('issues.index', [
            'employees' => Employee::where('status', 'active')->orderBy('name')->get(),
            'variants' => StockVariant::with('item')->where('quantity', '>', 0)->orderBy('size')->get()->sortBy('item.name'),
            'issues' => UniformIssue::with(['employee', 'variant.item'])->latest('issued_at')->paginate(15),
        ]);
    }

    public function store(Request $request)
    {
        $data = $request->validate([
            'employee_id' => ['required', 'exists:employees,id'],
            'stock_variant_id' => ['required', 'exists:stock_variants,id'],
            'quantity' => ['required', 'integer', 'min:1'],
            'issued_at' => ['required', 'date'],
            'notes' => ['nullable', 'string', 'max:500'],
        ]);

        DB::transaction(function () use ($data) {
            $employee = Employee::lockForUpdate()->findOrFail($data['employee_id']);
            if ($employee->status !== 'active') {
                throw ValidationException::withMessages(['employee_id' => 'Uniforms can only be issued to active employees.']);
            }

            $variant = StockVariant::lockForUpdate()->findOrFail($data['stock_variant_id']);
            if ($variant->quantity < $data['quantity']) {
                throw ValidationException::withMessages(['quantity' => "Only {$variant->quantity} item(s) are available in this size."]);
            }

            $issue = UniformIssue::create($data);
            $variant->decrement('quantity', $data['quantity']);
            StockMovement::create([
                'stock_variant_id' => $variant->id,
                'employee_id' => $employee->id,
                'uniform_issue_id' => $issue->id,
                'type' => 'issue',
                'quantity_change' => -$data['quantity'],
                'notes' => "Issued to {$employee->name}",
            ]);
        });

        return back()->with('success', 'Uniform issued and stock adjusted.');
    }
}