@extends('layouts.layout-horizontal')

@section('title', 'Edit Purchase Return')

@section('css')
<style>
    #itemsTable tbody tr:nth-child(even) { background: #f8f9fa; }
    #itemsTable tbody tr:nth-child(odd) { background: #fff; }

    #itemsTable thead th {
        position: sticky; top: 0; z-index: 2;
        background: #eef1f5; border-bottom: 2px solid #dee2e6;
        font-size: .825rem; text-transform: uppercase; letter-spacing: .3px; color: #6c757d;
        padding: 6px 4px; white-space: nowrap;
    }

    #itemsTable td { padding: 3px 4px; vertical-align: middle; font-size: .925rem; border: none; border-bottom: 1px solid #f0f0f0; }

    #itemsTable .row-num { color: #adb5bd; font-size: .825rem; text-align: center; width: 24px; user-select: none; }

    #itemsTable .form-control-sm {
        padding: 2px 4px; font-size: .925rem; height: 30px;
        border: 1px solid transparent; background: transparent; border-radius: 3px;
        transition: border-color .15s, background .15s;
    }
    #itemsTable .form-control-sm:focus {
        border-color: #86b7fe; background: #fff; box-shadow: 0 0 0 2px rgba(13,110,253,.12);
    }
    #itemsTable .form-control-sm:hover:not(:focus) { background: #f0f4f8; }

    #itemsTable .qty, #itemsTable .rate, #itemsTable .line-amt, #itemsTable .line-tot, #itemsTable .taxp {
        font-variant-numeric: tabular-nums; font-family: 'SF Mono', 'Cascadia Code', 'Consolas', monospace;
    }

    #itemsTable .line-amt { color: #495057; }
    #itemsTable .line-tot { color: #0d6efd; font-weight: 600; }

    #itemsTable tbody tr.row-empty td:not(:nth-child(2)) { opacity: .35; transition: opacity .2s; }
    #itemsTable tbody tr.row-empty:hover td, #itemsTable tbody tr.row-empty:focus-within td { opacity: 1; }
    #itemsTable tbody tr.row-filled td { opacity: 1; }

    #itemsTable tbody tr:focus-within { background: #e8f0fe !important; }

    #itemsTable .remove { opacity: 0; transition: opacity .15s; }
    #itemsTable tbody tr:hover .remove, #itemsTable tbody tr:focus-within .remove { opacity: 1; }

    #itemsTable .ts-wrapper { font-size: .875rem; }
    #itemsTable .ts-wrapper .ts-control {
        padding: 0 6px !important; min-height: 0 !important; height: 36px;
        line-height: 36px; border: 1px solid #dee2e6; background: #fff;
        box-shadow: none; border-radius: 3px; display: flex; align-items: center;
    }
    #itemsTable .ts-wrapper .ts-control > input { padding: 0 !important; margin: 0 !important; height: 34px; line-height: 34px; font-size: .875rem; }
    #itemsTable .ts-wrapper .ts-control .item { padding: 0 4px; font-size: .875rem; line-height: 34px; }
    #itemsTable .ts-wrapper.focus .ts-control { border-color: #86b7fe; box-shadow: 0 0 0 2px rgba(13,110,253,.12); }
    #itemsTable .ts-wrapper .ts-dropdown { font-size: .875rem; }
    #itemsTable .ts-wrapper .ts-dropdown .option { padding: 3px 6px; }
    #itemsTable .btn-sm { padding: 1px 6px; font-size: .875rem; }

    .items-scroll { max-height: 65vh; overflow-y: auto; border: 1px solid #dee2e6; border-radius: 6px; }

    .card-header .ts-wrapper .ts-control { height: 40px; min-height: 40px; font-size: 1.05rem; padding: 0 10px; display: flex; align-items: center; }
    .card-header .ts-wrapper .ts-control input { font-size: 1.05rem; height: 38px; }
    .card-header .ts-wrapper .ts-control .item { font-size: 1.05rem; line-height: 38px; }
    .card-header .ts-wrapper .ts-dropdown { font-size: 1rem; }

    /* Mobile — transform each row into a card with labeled inputs */
    @media (max-width: 767.98px) {
        .items-scroll { max-height: none; overflow: visible; border: none; border-radius: 0; }
        #itemsTable, #itemsTable > tbody { display: block; width: 100%; }
        #itemsTable thead { display: none; }
        #itemsTable tbody tr {
            position: relative;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 8px 10px;
            padding: 28px 12px 12px;
            margin-bottom: 10px;
            background: #fff !important;
            border: 1px solid #d0d7de !important;
            border-radius: 10px;
            box-shadow: 0 1px 2px rgba(0,0,0,.04);
        }
        #itemsTable tbody tr.row-empty td { opacity: 1 !important; }
        #itemsTable tbody tr > td {
            display: flex !important; flex-direction: column;
            padding: 0 !important; border: none !important;
            background: transparent !important; font-size: 1rem;
        }
        #itemsTable tbody tr > td[data-label]:not([data-label=""])::before {
            content: attr(data-label);
            font-size: .68rem; text-transform: uppercase; letter-spacing: .4px;
            color: #64748b; font-weight: 600; margin-bottom: 3px;
        }
        #itemsTable tbody tr > td.info-cell { display: none !important; }
        #itemsTable td.row-num {
            position: absolute; top: 7px; left: 12px;
            font-size: .72rem; color: #94a3b8;
        }
        #itemsTable tbody tr > td[data-label="Product"] { grid-column: 1 / -1; }
        #itemsTable tbody tr > td[data-label="Total"] {
            grid-column: 1 / -1;
            background: #f1f5f9 !important;
            padding: 6px 10px !important;
            border-radius: 6px;
            margin-top: 2px;
        }
        #itemsTable tbody tr > td.remove-cell {
            position: absolute; top: 4px; right: 4px;
        }
        #itemsTable .remove {
            opacity: 1 !important;
            min-width: 32px; min-height: 32px;
            font-size: 1rem; line-height: 1; padding: 4px 9px !important;
        }
        #itemsTable .form-control-sm {
            height: 42px !important; font-size: 1rem !important;
            padding: 8px 10px !important;
            border: 1px solid #d0d7de !important; background: #fff !important;
            border-radius: 6px !important;
        }
        #itemsTable .ts-wrapper .ts-control {
            height: 46px !important; min-height: 46px !important;
            line-height: 44px !important; font-size: 1rem !important;
            padding: 0 10px !important;
        }
        #itemsTable .ts-wrapper .ts-control > input,
        #itemsTable .ts-wrapper .ts-control .item {
            height: 44px !important; line-height: 44px !important; font-size: 1rem !important;
        }
        .card-body { padding: 10px !important; }

        /* Sticky totals bar — stack totals row above full-width action buttons */
        #stickyTotalsBar > div { padding: 0 10px !important; max-width: 100% !important; }
        #stickyTotalsBar div[style*="width:1px"],
        #stickyTotalsBar div[style*="width:2px"] { display: none !important; }
        #pfRow { padding: 6px 0 !important; gap: 8px !important; }
        #pfRow input { height: 32px !important; font-size: .8rem !important; }
        #stickyTotalsBar #amount_total,
        #stickyTotalsBar #tax_total { font-size: .9rem !important; width: auto !important; min-width: 70px; }
        #stickyTotalsBar #discount,
        #stickyTotalsBar #roundoff { font-size: .9rem !important; width: 70px !important; height: 32px !important; }
        #stickyTotalsBar #grand_total { font-size: 1.35rem !important; width: 120px !important; }
        #pfToggleBtn { padding: 6px 10px !important; font-size: .72rem !important; }
        #stickyTotalsBar > div > div:not(#pfRow) {
            flex-direction: column !important;
            align-items: stretch !important;
            gap: 8px !important;
            padding: 8px 0 !important;
        }
        #stickyTotalsBar > div > div:not(#pfRow) > div:first-child {
            gap: 12px !important;
            justify-content: space-between !important;
        }
        #stickyTotalsBar > div > div:not(#pfRow) > div:last-child {
            display: grid !important;
            grid-template-columns: 1fr 1fr;
            gap: 8px;
        }
        #stickyTotalsBar .btn {
            width: 100% !important;
            padding: 10px 8px !important;
            font-size: .85rem !important;
            margin: 0 !important;
        }
        #stickyTotalsBar kbd { display: none !important; }
        body { padding-bottom: 100px; }
    }
</style>
@endsection

@section('content')
    <div class="card">
        <form method="POST" action="{{ route('purchase-returns.update', $purchaseReturn->id) }}" id="purchaseReturnForm">
            @csrf
            @method('PUT')
            <input type="hidden" name="company_id" value="{{ currentCompanyId() }}">
            <input type="hidden" name="mode" value="{{ $mode }}">

            <div class="card-header d-flex align-items-center justify-content-between flex-wrap gap-2">
                <div class="d-flex align-items-center gap-2 flex-wrap">
                    <a href="{{ route('purchase-returns.index') }}" class="text-muted" style="font-size:.85rem"><i class="ph-duotone ph-arrow-left"></i></a>
                    <h5 class="mb-0">Edit Purchase Return @if($purchaseReturn->bill_no)<span class="text-muted">#{{ $purchaseReturn->bill_no }}</span>@endif</h5>
                    @if ($mode == 'cash')
                        <span class="badge bg-dark rounded-pill">Cash Mode</span>
                    @else
                        <span class="badge bg-primary rounded-pill">Bill Mode</span>
                    @endif
                </div>
            </div>

            <div class="card-body">
                <div class="row g-3">
                    <div class="col-md-4">
                        <label class="form-label d-flex align-items-center">Party name <a class="btn btn-primary btn-sm ms-auto" href="{{ route('customers.create') }}?from_dropdown=1" target="_blank">Add</a></label>
                        <select name="party_id" id="party_id" required>
                            <option value=""></option>
                            @foreach ($parties as $p)
                                <option value="{{ $p->id }}" data-gst="{{ $p->gst_number }}" @selected(old('party_id', $purchaseReturn->party_id) == $p->id)>{{ $p->name }}@if($p->payment_type === 'cash') (Cash)@endif</option>
                            @endforeach
                        </select>
                        @error('party_id')
                            <div class="text-danger small">{{ $message }}</div>
                        @enderror
                        @include('partials._party-details')
                    </div>

                    <div class="col-md-2">
                        <label class="form-label">Invoice date</label>
                        <input type="date" name="invoice_date"
                            class="form-control @error('invoice_date') is-invalid @enderror"
                            value="{{ old('invoice_date', optional($purchaseReturn->invoice_date)->toDateString()) }}" required>
                        @error('invoice_date')
                            <div class="invalid-feedback">{{ $message }}</div>
                        @enderror
                    </div>
                    <div class="col-md-2">
                        <label class="form-label">Bill no</label>
                        <input type="text" name="bill_no" class="form-control" value="{{ old('bill_no', $purchaseReturn->bill_no) }}">
                    </div>

                    <div class="col-md-2">
                        <label class="form-label">Reason of return</label>
                        <select name="reason" class="form-select @error('reason') is-invalid @enderror" required>
                            <option value="damage"   @selected(old('reason', $purchaseReturn->reason) == 'damage')>Damage</option>
                            <option value="discount" @selected(old('reason', $purchaseReturn->reason) == 'discount')>Discount</option>
                        </select>
                        @error('reason')
                            <div class="invalid-feedback">{{ $message }}</div>
                        @enderror
                    </div>
                </div>

                <hr class="my-4">

                {{-- Items table --}}
                <div class="d-flex align-items-center justify-content-between mb-2">
                    <span style="font-weight:600;font-size:.85rem;color:#334155">Line Items</span>
                    <div class="d-flex gap-2">
                        <a class="btn btn-sm btn-outline-success" href="{{ route('products.create') }}?from_dropdown=1" target="_blank" style="font-size:.75rem;padding:3px 10px"><i class="ph-duotone ph-plus me-1"></i>New Product</a>
                        <button class="btn btn-sm btn-primary" type="button" id="addRowBtn" title="Alt+A" style="font-size:.75rem;padding:3px 10px">+ Row <kbd class="ms-1 bg-light text-dark border" style="font-size:.6rem">Alt+A</kbd></button>
                    </div>
                </div>

                <div class="items-scroll">
                    <table class="table table-sm align-middle mb-0" id="itemsTable">
                        <thead>
                            <tr>
                                <th style="width:24px">#</th>
                                <th style="min-width:220px">Product</th>
                                @if($mode !== 'cash')<th style="width:110px">HSN</th>@endif
                                <th style="width:75px">Unit</th>
                                <th style="width:120px" class="text-center">Qty</th>
                                <th style="width:140px" class="text-center">Rate</th>
                                @if($mode !== 'cash')<th style="width:100px" class="text-center">Tax%</th>@endif
                                <th style="width:160px" class="text-center">Total</th>
                                <th style="width:28px"></th>
                            </tr>
                        </thead>
                        <tbody></tbody>
                    </table>
                </div>

            </div>
        </form>
    </div>

    {{-- Sticky bottom totals bar --}}
    <div id="stickyTotalsBar" style="position:fixed;bottom:0;left:0;right:0;z-index:1050;background:linear-gradient(180deg,#1a2332 0%,#0f172a 100%);border-top:3px solid #3b82f6;padding:0;box-shadow:0 -8px 30px rgba(0,0,0,.35);">
        <div style="max-width:1400px;margin:0 auto;padding:0 20px;">
            {{-- P&F row --}}
            <div id="pfRow" class="d-flex align-items-center gap-3 flex-wrap" style="padding:6px 0 0;border-bottom:1px solid #1e293b">
                <span style="color:#64748b;font-size:.65rem;text-transform:uppercase;letter-spacing:.5px">P&amp;F</span>
                <input type="number" step="0.01" name="pf_amount" id="pf_amount" form="purchaseReturnForm" placeholder="P&F Amt"
                    value="{{ old('pf_amount', number_format((float)($purchaseReturn->pf_amount ?? 0), 2, '.', '')) }}"
                    style="background:#1e293b;border:1px solid #334155;border-radius:4px;color:#e2e8f0;font-size:.85rem;width:100px;text-align:right;padding:2px 6px;height:28px" />
                <input type="number" step="0.01" name="pf_tax_percent" id="pf_tax_percent" form="purchaseReturnForm" placeholder="Tax %"
                    value="{{ old('pf_tax_percent', number_format((float)($purchaseReturn->pf_tax_percent ?? 0), 2, '.', '')) }}"
                    style="background:#1e293b;border:1px solid #334155;border-radius:4px;color:#e2e8f0;font-size:.85rem;width:70px;text-align:right;padding:2px 6px;height:28px" />
                <span style="color:#475569;font-size:.75rem">Tax:</span>
                <input type="number" step="0.01" name="pf_tax_amount" id="pf_tax_amount" form="purchaseReturnForm" readonly
                    value="{{ old('pf_tax_amount', number_format((float)($purchaseReturn->pf_tax_amount ?? 0), 2, '.', '')) }}"
                    style="background:transparent;border:none;color:#94a3b8;font-size:.85rem;width:80px;text-align:right" />
            </div>
            <div class="d-flex align-items-center justify-content-between flex-wrap gap-2" style="padding:10px 0;">
                <div class="d-flex align-items-center gap-4 flex-wrap">
                    <div class="d-flex flex-column align-items-end">
                        <span style="color:#64748b;font-size:.6rem;text-transform:uppercase;letter-spacing:.5px">Amount</span>
                        <input name="amount_total" id="amount_total" form="purchaseReturnForm" readonly
                            style="background:transparent;border:none;color:#cbd5e1;font-size:.95rem;width:110px;text-align:right;font-weight:500" />
                    </div>
                    <div style="width:1px;height:32px;background:#2d3a4d"></div>
                    <div class="d-flex flex-column align-items-end">
                        <span style="color:#64748b;font-size:.6rem;text-transform:uppercase;letter-spacing:.5px">Tax</span>
                        <input name="tax_total" id="tax_total" form="purchaseReturnForm" readonly
                            style="background:transparent;border:none;color:#cbd5e1;font-size:.95rem;width:100px;text-align:right;font-weight:500" />
                    </div>
                    <div style="width:1px;height:32px;background:#2d3a4d"></div>
                    <div class="d-flex flex-column align-items-end">
                        <span style="color:#64748b;font-size:.6rem;text-transform:uppercase;letter-spacing:.5px">Roundoff</span>
                        <input name="roundoff" id="roundoff"
                            value="{{ old('roundoff', number_format((float)($purchaseReturn->roundoff ?? 0), 2, '.', '')) }}" form="purchaseReturnForm"
                            style="background:#1e293b;border:1px solid #334155;border-radius:4px;color:#e2e8f0;font-size:.95rem;width:80px;text-align:right;padding:2px 6px;height:30px" />
                    </div>
                    <div style="width:2px;height:36px;background:#3b82f6;border-radius:1px"></div>
                    <div class="d-flex flex-column align-items-end">
                        <span style="color:#3b82f6;font-size:.65rem;text-transform:uppercase;letter-spacing:.5px;font-weight:700">Grand Total</span>
                        <input name="grand_total" id="grand_total" form="purchaseReturnForm" readonly
                            style="background:transparent;border:none;color:#f8fafc;font-size:1.5rem;width:160px;text-align:right;font-weight:800;letter-spacing:-.5px" />
                    </div>
                </div>

                <div class="d-flex align-items-center gap-2">
                    <button class="btn btn-outline-light" id="btnSave" form="purchaseReturnForm" style="padding:8px 20px;font-size:.85rem">
                        <i class="ph-duotone ph-check-circle me-1"></i> Update Purchase Return <kbd class="ms-1 text-light border-0" style="font-size:.65rem;opacity:.5">Alt+S</kbd>
                    </button>
                </div>
            </div>
        </div>
    </div>
    <div style="height:100px"></div>
@endsection

@push('scripts')
    @php
        $seedItemsData = $purchaseReturn->items->map(function ($it) {
            return [
                'product_id'  => $it->product_id,
                'name'        => $it->product->name ?? 'Unknown',
                'hsn'         => $it->hsn,
                'unit'        => $it->unit,
                'qty'         => (float) $it->qty,
                'rate'        => (float) $it->rate,
                'tax_percent' => (float) $it->tax_percent,
            ];
        })->values();
    @endphp
    <script>
        (function () {
            const isCashMode = @json($mode === 'cash');
            const itemsTbody = document.querySelector('#itemsTable tbody');
            const taxTotalEl  = document.getElementById('tax_total');
            const amtTotalEl  = document.getElementById('amount_total');
            const roundoffEl  = document.getElementById('roundoff');
            const grandEl     = document.getElementById('grand_total');
            const pfAmtEl     = document.getElementById('pf_amount');
            const pfTaxPctEl  = document.getElementById('pf_tax_percent');
            const pfTaxAmtEl  = document.getElementById('pf_tax_amount');

            const productOptions = @json($products).map(p => ({
                value: String(p.id),
                text: (p.product_id || '') + ' — ' + p.name,
                name: p.name,
                hsn: p.hsn || '',
                pid: p.product_id || ''
            }));

            const rowTomSelects = new Map();
            let rowCounter = 0;

            function addEmptyRow() {
                const idx = rowCounter++;
                const rowNum = itemsTbody.querySelectorAll('tr').length + 1;
                const row = document.createElement('tr');
                row.dataset.rowIdx = idx;
                row.className = 'row-empty';

                row.innerHTML = `
                    <td class="row-num">${rowNum}</td>
                    <td data-label="Product">
                        <select class="row-product-select" id="prod_select_${idx}"><option value=""></option></select>
                    </td>
                    ${isCashMode ? '' : `<td data-label="HSN"><input class="form-control form-control-sm" name="items[${idx}][hsn]" value=""></td>`}
                    <td data-label="Unit"><input class="form-control form-control-sm" name="items[${idx}][unit]" value=""></td>
                    <td data-label="Qty"><input type="number" step="0.001" class="form-control form-control-sm text-end qty" name="items[${idx}][qty]" value=""></td>
                    <td data-label="Rate"><input type="number" step="0.01" class="form-control form-control-sm text-end rate" name="items[${idx}][rate]" value=""></td>
                    ${isCashMode
                        ? ''
                        : `<td data-label="Tax %"><input type="number" step="0.01" class="form-control form-control-sm text-end taxp" name="items[${idx}][tax_percent]" value=""></td>`
                    }
                    <td data-label="Total"><input type="number" step="0.01" class="form-control form-control-sm text-end line-tot" name="items[${idx}][line_total]" value="">
                        <input type="hidden" name="items[${idx}][product_id]" value="" class="row-product-id">
                        <input type="hidden" name="items[${idx}][line_amount]" value="0" class="line-amt">
                        <input type="hidden" name="items[${idx}][line_tax_amount]" value="0">
                        ${isCashMode ? `<input type="hidden" class="taxp" name="items[${idx}][tax_percent]" value="0">` : ''}
                    </td>
                    <td class="remove-cell"><button type="button" class="btn btn-sm btn-outline-danger remove">×</button></td>
                `;
                itemsTbody.appendChild(row);
                initRowTomSelect(row, idx);
                return row;
            }

            function addFilledRow(pid, name, hsn, unit, qty, rate, taxp) {
                const row = addEmptyRow();
                row.classList.remove('row-empty'); row.classList.add('row-filled');
                const idx = row.dataset.rowIdx;

                row.querySelector('.row-product-id').value = pid;
                const hsnEl = row.querySelector('input[name$="[hsn]"]');
                if (hsnEl) hsnEl.value = hsn || '';
                row.querySelector('input[name$="[unit]"]').value = unit || '';
                row.querySelector('.qty').value = parseFloat(qty) || 0;
                row.querySelector('.rate').value = parseFloat(rate) || '';
                row.querySelector('.taxp').value = parseFloat(taxp) || 0;

                const ts = rowTomSelects.get(parseInt(idx));
                if (ts) {
                    if (!ts.options[String(pid)]) ts.addOption({ value: String(pid), text: name, name });
                    ts.setValue(String(pid), true);
                }
                recalcRowForward(row);
            }

            const addProductUrl = `{{ route('products.create') }}?from_dropdown=1`;

            function initRowTomSelect(row, idx) {
                const selectEl = row.querySelector(`#prod_select_${idx}`);
                const ts = new TomSelect(selectEl, {
                    dropdownParent: 'body',
                    maxOptions: 50, allowEmptyOption: true, closeAfterSelect: true,
                    placeholder: 'Search name, ID or HSN...',
                    options: JSON.parse(JSON.stringify(productOptions)), items: [], highlight: true,
                    searchField: ['text', 'hsn', 'pid', 'name'],
                    onDropdownOpen: function() { this.setActiveOption(null); this.control_input.value = ''; },
                    render: {
                        option: function(data, escape) {
                            const hsn = data.hsn ? `<span style="color:#999;font-size:.7rem"> HSN:${escape(data.hsn)}</span>` : '';
                            return `<div>${escape(data.text)}${hsn}</div>`;
                        },
                        no_results: function() {
                            return `<div class="no-results" style="padding:6px 10px;font-size:.8rem">No match found — <a href="${addProductUrl}" target="_blank" style="color:#0d6efd">+ Add new product</a></div>`;
                        }
                    },
                    onItemAdd: function() { this.control_input.value = ''; }
                });

                ts.on('change', async function(value) {
                    const productIdInput = row.querySelector('.row-product-id');

                    if (!value) {
                        productIdInput.value = '';
                        row.classList.remove('row-filled'); row.classList.add('row-empty');
                        ['[hsn]','[unit]'].forEach(s => { const el = row.querySelector(`input[name$="${s}"]`); if (el) el.value = ''; });
                        row.querySelector('.qty').value = '';
                        row.querySelector('.rate').value = '';
                        row.querySelector('.line-amt').value = '0';
                        row.querySelector('.line-tot').value = '';
                        row.querySelector('.taxp').value = isCashMode ? '0' : '';
                        recalcRowForward(row);
                        return;
                    }

                    row.classList.remove('row-empty'); row.classList.add('row-filled');
                    maybeAutoAddRows();
                    productIdInput.value = value;

                    try {
                        const res = await fetch(`{{ url('api/products') }}/${value}/metrics?company_id={{ currentCompanyId() }}`);
                        const d = await res.json();

                        const hsnInput = row.querySelector('input[name$="[hsn]"]');
                        if (hsnInput) hsnInput.value = d.hsn || '';
                        row.querySelector('input[name$="[unit]"]').value = d.unit || '';
                        row.querySelector('.taxp').value = isCashMode ? 0 : (d.tax_percent || '0');

                        if (d.last && d.last.length && d.last[0].rate) {
                            row.querySelector('.rate').value = parseFloat(d.last[0].rate).toFixed(2);
                        } else if (d.mrp) {
                            row.querySelector('.rate').value = parseFloat(d.mrp).toFixed(2);
                        } else {
                            row.querySelector('.rate').value = '';
                        }
                        if (!row.querySelector('.qty').value) row.querySelector('.qty').value = 1;

                        recalcRowForward(row);
                        row.querySelector('.qty').focus();
                        row.querySelector('.qty').select();
                    } catch (err) { console.error(err); }
                });

                rowTomSelects.set(idx, ts);
            }

            function recalcRowForward(tr) {
                const qty = parseFloat(tr.querySelector('.qty')?.value) || 0;
                const rate = parseFloat(tr.querySelector('.rate')?.value) || 0;
                const taxp = parseFloat(tr.querySelector('.taxp')?.value) || 0;
                const amount = +(qty * rate).toFixed(2);
                const taxAmt = +((amount * taxp) / 100).toFixed(2);
                const total = +(amount + taxAmt).toFixed(2);
                tr.querySelector('.line-amt').value = amount.toFixed(2);
                tr.querySelector('input[name$="[line_tax_amount]"]').value = taxAmt.toFixed(2);
                tr.querySelector('.line-tot').value = total ? total.toFixed(2) : '';
                recalcTotals();
            }

            function reverseFromTotal(tr) {
                const qty = parseFloat(tr.querySelector('.qty')?.value) || 0;
                const total = parseFloat(tr.querySelector('.line-tot')?.value) || 0;
                const taxp = parseFloat(tr.querySelector('.taxp')?.value) || 0;
                const amount = +(total / (1 + taxp / 100)).toFixed(2);
                const taxAmt = +(total - amount).toFixed(2);
                tr.querySelector('.line-amt').value = amount.toFixed(2);
                tr.querySelector('input[name$="[line_tax_amount]"]').value = taxAmt.toFixed(2);
                if (qty > 0) {
                    tr.querySelector('.rate').value = (+(amount / qty).toFixed(2)).toFixed(2);
                }
                recalcTotals();
            }

            function reindexRows() {
                itemsTbody.querySelectorAll('tr').forEach((row, i) => {
                    const numCell = row.querySelector('.row-num');
                    if (numCell) numCell.textContent = i + 1;
                    row.querySelectorAll('input[name]').forEach(inp => {
                        inp.name = inp.name.replace(/items\[\d+\]/, `items[${i}]`);
                    });
                });
            }

            document.getElementById('addRowBtn').addEventListener('click', function() {
                const row = addEmptyRow();
                const ts = rowTomSelects.get(parseInt(row.dataset.rowIdx));
                if (ts) setTimeout(() => ts.focus(), 50);
            });

            document.addEventListener('keydown', function(e) {
                if (!e.altKey) return;
                if (e.key === 'a') { e.preventDefault(); document.getElementById('addRowBtn').click(); }
                if (e.key === 's') { e.preventDefault(); document.getElementById('btnSave').click(); }
            });

            // Seed existing items first, then top up with empties
            const seedItems = @json($seedItemsData);
            seedItems.forEach(it => {
                addFilledRow(it.product_id, it.name, it.hsn ?? '', it.unit ?? '', it.qty, it.rate, it.tax_percent);
            });
            for (let i = 0; i < 3; i++) addEmptyRow();

            roundoffEl.dataset.manual = '1';

            function maybeAutoAddRows() {
                const emptyCount = itemsTbody.querySelectorAll('tr.row-empty').length;
                if (emptyCount <= 1) {
                    for (let i = 0; i < 5; i++) addEmptyRow();
                }
            }

            itemsTbody.addEventListener('input', function (e) {
                const tr = e.target.closest('tr');
                if (!tr) return;
                if (e.target.classList.contains('line-tot')) {
                    reverseFromTotal(tr);
                } else {
                    recalcRowForward(tr);
                }
            });

            itemsTbody.addEventListener('click', function (e) {
                if (e.target.classList.contains('remove')) {
                    const row = e.target.closest('tr');
                    const idx = parseInt(row.dataset.rowIdx);
                    const ts = rowTomSelects.get(idx);
                    if (ts) { ts.destroy(); rowTomSelects.delete(idx); }
                    row.remove(); reindexRows(); recalcTotals();
                }
            });

            document.getElementById('purchaseReturnForm').addEventListener('submit', function() {
                itemsTbody.querySelectorAll('tr').forEach(row => {
                    const pid = row.querySelector('.row-product-id');
                    if (!pid || !pid.value) row.querySelectorAll('input[name]').forEach(inp => inp.removeAttribute('name'));
                });
                reindexRows();
            });

            roundoffEl.addEventListener('input', () => { roundoffEl.dataset.manual = '1'; recalcTotals(); });
            pfAmtEl.addEventListener('input', recalcTotals);
            pfTaxPctEl.addEventListener('input', recalcTotals);

            function recalcTotals() {
                let tax = 0, amt = 0;
                itemsTbody.querySelectorAll('tr').forEach(tr => {
                    amt += parseFloat(tr.querySelector('.line-amt')?.value) || 0;
                    tax += parseFloat(tr.querySelector('input[name$="[line_tax_amount]"]')?.value) || 0;
                });
                taxTotalEl.value = tax.toFixed(2);
                amtTotalEl.value = amt.toFixed(2);
                const pfAmt = parseFloat(pfAmtEl.value) || 0;
                const pfTaxPct = parseFloat(pfTaxPctEl.value) || 0;
                const pfTax = +((pfAmt * pfTaxPct) / 100).toFixed(2);
                pfTaxAmtEl.value = pfTax.toFixed(2);
                if (!roundoffEl.dataset.manual) {
                    const raw = amt + tax + pfAmt + pfTax;
                    roundoffEl.value = (Math.round(raw) - raw).toFixed(2);
                }
                const grand = amt + tax + pfAmt + pfTax + (parseFloat(roundoffEl.value) || 0);
                grandEl.value = grand.toFixed(2);
            }

            recalcTotals();

            const productChannel = new BroadcastChannel('product_created');
            productChannel.onmessage = function (event) {
                const product = event.data;
                if (!product || !product.id) return;
                const newOpt = { value: String(product.id), text: (product.product_id || '') + ' — ' + product.name, name: product.name, hsn: product.hsn || '', pid: product.product_id || '' };
                productOptions.push(newOpt);
                rowTomSelects.forEach(ts => { if (!ts.options[String(product.id)]) ts.addOption(newOpt); });
            };
        })();

        // --- Party Tom Select ---
        const tomPartySelect = new TomSelect('#party_id', {
            maxOptions: null,
            allowEmptyOption: true,
            closeAfterSelect: true,
            placeholder: 'Search party...',
            highlight: true,
            searchField: ['text', 'gst'],
            render: {
                option: function(data, escape) {
                    const gst = data.gst ? '<span style="color:#999;font-size:.7rem;margin-left:6px">GST: ' + escape(data.gst) + '</span>' : '';
                    return '<div>' + escape(data.text) + gst + '</div>';
                },
                item: function(data, escape) {
                    return '<div>' + escape(data.text) + '</div>';
                }
            },
            onItemAdd: function() { this.control_input.value = ''; }
        });

        tomPartySelect.on('change', function(value) {
            loadPartyDetails(value);
        });

        if (tomPartySelect.getValue()) {
            tomPartySelect.trigger('change', tomPartySelect.getValue());
        }

        const partyChannel = new BroadcastChannel('customer_created');
        partyChannel.onmessage = function (event) {
            const customer = event.data;
            if (customer.party_type !== 'purchase' && customer.party_type !== 'both') return;
            if (tomPartySelect.options[customer.id]) return;
            let label = customer.name;
            if (customer.payment_type === 'cash') label += ' (Cash)';
            tomPartySelect.addOption({ value: customer.id, text: label, gst: customer.gst_number || '' });
            tomPartySelect.setValue(customer.id);
        };
    </script>
@endpush