<?php

namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;
use Illuminate\Http\Request;
use App\Models\Order;
use App\Models\OrderItem;
use App\Models\MarkList;

class AdminOrderController extends Controller
{
    public function index()
    {
        $orders = Order::latest()->get();
        $markList = MarkList::where('status', 'active')->get();

        return view('admin.dashboard', compact('orders', 'markList'));
    }

    // -------------------------------------------------------------------------
    // STEP 1 : ADD TEMPORARY ITEM
    // -------------------------------------------------------------------------

    public function addTempItem(Request $request)
    {
        // Validate item fields
        $item = $request->validate([
            'mark_no' => 'required',
            'origin' => 'required',
            'destination' => 'required',
            'description' => 'required|string',
            'ctn' => 'nullable|numeric',
            'qty' => 'nullable|numeric',
            'ttl_qty' => 'nullable|numeric',
            'unit' => 'nullable|string',
            'price' => 'nullable|numeric',
            'ttl_amount' => 'nullable|numeric',
            'cbm' => 'nullable|numeric',
            'ttl_cbm' => 'nullable|numeric',
            'kg' => 'nullable|numeric',
            'ttl_kg' => 'nullable|numeric',
            'shop_no' => 'nullable|string',
        ]);

        // ❌ Prevent changing mark_no once first item added
        if (session()->has('mark_no') && session('mark_no') != $request->mark_no) {
            return redirect()->to(route('admin.orders.index') . '#createOrderForm')
                             ->with('error', 'You must finish or clear the current order before changing Mark No.');
        }

        // Save mark, origin, destination ONLY ONCE
        if (!session()->has('mark_no')) {
            session([
                'mark_no' => $request->mark_no,
                'origin' => $request->origin,
                'destination' => $request->destination
            ]);
        }

        // ❌ DO NOT overwrite these values again
        // session(['mark_no' => $request->mark_no]);
        // session(['origin' => $request->origin]);
        // session(['destination' => $request->destination]);

        // Add new sub-item into session
        session()->push('temp_order_items', $item);

        return redirect()->to(route('admin.orders.index') . '#createOrderForm')
                         ->with('success', 'Item added.');
    }

    // -------------------------------------------------------------------------
    // STEP 2 : DELETE TEMPORARY ITEM
    // -------------------------------------------------------------------------

    public function deleteTempItem(Request $request)
    {
        $index = $request->index;

        $items = session('temp_order_items', []);

        if (isset($items[$index])) {
            unset($items[$index]);
            session(['temp_order_items' => array_values($items)]);
        }

        // If no items left → reset mark_no lock
        if (empty($items)) {
            session()->forget(['mark_no', 'origin', 'destination']);
        }

        return redirect()->to(route('admin.orders.index') . '#createOrderForm')
                         ->with('success', 'Item removed successfully.');
    }

    // -------------------------------------------------------------------------
    // STEP 3 : FINISH ORDER
    // -------------------------------------------------------------------------

    public function finishOrder(Request $request)
{
    $request->validate([
        'mark_no' => 'required',
        'origin' => 'required',
        'destination' => 'required',
    ]);

    $items = session('temp_order_items', []);

    if (empty($items)) {
        return redirect()->to(route('admin.orders.index') . '#createOrderForm')
                         ->with('error', 'Add at least one item before finishing.');
    }

    // =======================
    // GENERATE ORDER ID
    // =======================
    $year = date('y');
    $prefix = "KNT-$year-";

    $lastOrder = Order::latest('id')->first();
    $nextNumber = $lastOrder ? intval(substr($lastOrder->order_id, -8)) + 1 : 1;

    $orderId = $prefix . str_pad($nextNumber, 8, '0', STR_PAD_LEFT);

    // =======================
    // TOTAL SUMS
    // =======================
    $total_ctn = array_sum(array_column($items, 'ctn'));
    $total_qty = array_sum(array_column($items, 'qty'));
    $total_ttl_qty = array_sum(array_column($items, 'ttl_qty'));
    $total_amount = array_sum(array_column($items, 'ttl_amount'));
    $total_cbm = array_sum(array_column($items, 'cbm'));
    $total_ttl_cbm = array_sum(array_column($items, 'ttl_cbm'));
    $total_kg = array_sum(array_column($items, 'kg'));
    $total_ttl_kg = array_sum(array_column($items, 'ttl_kg'));

    // =======================
    // CREATE ORDER
    // =======================
    $order = Order::create([
        'order_id' => $orderId,
        'mark_no' => $request->mark_no,
        'origin' => $request->origin,
        'destination' => $request->destination,
        'ctn' => $total_ctn,
        'qty' => $total_qty,
        'ttl_qty' => $total_ttl_qty,
        'ttl_amount' => $total_amount,
        'cbm' => $total_cbm,
        'ttl_cbm' => $total_ttl_cbm,
        'kg' => $total_kg,
        'ttl_kg' => $total_ttl_kg,
        'status' => 'pending',
    ]);

    // SAVE ORDER ITEMS
    foreach ($items as $item) {
        OrderItem::create([
            'order_id' => $order->id,
            'description' => $item['description'],
            'ctn' => $item['ctn'],
            'qty' => $item['qty'],
            'ttl_qty' => $item['ttl_qty'],
            'unit' => $item['unit'],
            'price' => $item['price'],
            'ttl_amount' => $item['ttl_amount'],
            'cbm' => $item['cbm'],
            'ttl_cbm' => $item['ttl_cbm'],
            'kg' => $item['kg'],
            'ttl_kg' => $item['ttl_kg'],
            'shop_no' => $item['shop_no'],
        ]);
    }

    // =======================
    // INVOICE CREATION START
    // =======================

    // 1. Auto-generate invoice number
    $lastInvoice = \App\Models\Invoice::latest()->first();
    $nextInvoice = $lastInvoice ? $lastInvoice->id + 1 : 1;
    $invoiceNumber = 'INV-' . date('Y') . '-' . str_pad($nextInvoice, 6, '0', STR_PAD_LEFT);

    // 2. Fetch customer (using mark list → customer_id)
    $markList = MarkList::where('mark_no', $order->mark_no)->first();
    $customer = null;

    if ($markList && $markList->customer_id) {
        $customer = \App\Models\User::where('customer_id', $markList->customer_id)->first();
    }

    // 3. Create Invoice Record
    $invoice = \App\Models\Invoice::create([
        'order_id' => $order->id,
        'customer_id' => $customer->id ?? null,
        'mark_no' => $order->mark_no,

        'invoice_number' => $invoiceNumber,
        'invoice_date' => now(),
        'due_date' => now()->addDays(10),

        'payment_method' => null,
        'reference_no' => null,
        'status' => 'pending',

        'final_amount' => $total_amount,
        'gst_percent' => 0,
        'gst_amount' => 0,
        'final_amount_with_gst' => $total_amount,

        // snapshot customer fields
        'customer_name' => $customer->customer_name ?? null,
        'company_name' => $customer->company_name ?? null,
        'customer_email' => $customer->email ?? null,
        'customer_mobile' => $customer->mobile_no ?? null,
        'customer_address' => $customer->address ?? null,
        'pincode' => $customer->pincode ?? null,

        'notes' => null,
    ]);

    // 4. Clone order items into invoice_items
    foreach ($order->items as $item) {
        \App\Models\InvoiceItem::create([
            'invoice_id' => $invoice->id,
            'description' => $item->description,
            'ctn' => $item->ctn,
            'qty' => $item->qty,
            'ttl_qty' => $item->ttl_qty,
            'unit' => $item->unit,
            'price' => $item->price,
            'ttl_amount' => $item->ttl_amount,
            'cbm' => $item->cbm,
            'ttl_cbm' => $item->ttl_cbm,
            'kg' => $item->kg,
            'ttl_kg' => $item->ttl_kg,
            'shop_no' => $item->shop_no,
        ]);
    }

    // 5. TODO: PDF generation (I will add this later)
    $invoice->pdf_path = null; // placeholder for now
    $invoice->save();

    // =======================
    // END INVOICE CREATION
    // =======================

    // CLEAR TEMP DATA
    session()->forget(['temp_order_items', 'mark_no', 'origin', 'destination']);

    return redirect()->route('admin.orders.index')
                     ->with('success', 'Order + Invoice created successfully.');
}


    // -------------------------------------------------------------------------
    // ORDER SHOW PAGE
    // -------------------------------------------------------------------------

    public function show($id)
    {
        $order = Order::with('items', 'markList')->findOrFail($id);

        $user = null;
        if ($order->markList && $order->markList->customer_id) {
            $user = \App\Models\User::where('customer_id', $order->markList->customer_id)->first();
        }

        return view('admin.orders_show', compact('order', 'user'));
    }

    public function popup($id)
    {
        // Load order with items + markList
        $order = Order::with(['items', 'markList'])->findOrFail($id);

        // Fetch user based on markList customer_id (same as show method)
        $user = null;
        if ($order->markList && $order->markList->customer_id) {
            $user = \App\Models\User::where('customer_id', $order->markList->customer_id)->first();
        }

        return view('admin.popup', compact('order', 'user'));
    }


    public function resetTemp()
    {
        session()->forget(['temp_order_items', 'mark_no', 'origin', 'destination']);

        return redirect()->to(route('admin.orders.index') . '#createOrderForm')
                        ->with('success', 'Order reset successfully.');
    }

    public function orderShow()
    {
        $orders = Order::with([
            'markList',     // company, customer, origin, destination, date
            'shipments',    // shipment_id, shipment_date, status
            'invoice'       // invoice number, dates, amounts, status
        ])
        ->latest('id') // show latest orders first
        ->get();

        return view('admin.orders', compact('orders'));
    }

}