@php
    $purchaseOrder = $purchaseOrder ?? null;
    $isEdit = $purchaseOrder !== null;
@endphp

<div class="row">
    <div>
        <label for="supplier_id">Supplier</label>
        <select name="supplier_id" id="supplier_id" required>
            <option value="">— Select supplier —</option>
            @foreach ($suppliers ?? [] as $supplier)
                <option value="{{ $supplier->id }}" @selected((string) old('supplier_id', $purchaseOrder?->supplier_id) === (string) $supplier->id)>{{ $supplier->name }}</option>
            @endforeach
        </select>
    </div>
    <div>
        <label for="transaction_date">Transaction date</label>
        <input type="date" name="transaction_date" id="transaction_date" value="{{ old('transaction_date', $purchaseOrder?->transaction_date?->toDateString() ?? now()->toDateString()) }}" required>
    </div>
    <div>
        <label for="reference_number">Reference number</label>
        <input type="text" name="reference_number" id="reference_number" value="{{ old('reference_number', $purchaseOrder?->reference_number) }}">
    </div>
    <div>
        <label for="reference_date">Reference date</label>
        <input type="date" name="reference_date" id="reference_date" value="{{ old('reference_date', $purchaseOrder?->reference_date?->toDateString()) }}">
    </div>
</div>

<label for="remarks">Remarks</label>
<textarea name="remarks" id="remarks">{{ old('remarks', $purchaseOrder?->remarks) }}</textarea>

@php
    $oldLines = old('lines');
    if (is_array($oldLines) && count($oldLines) > 0) {
        $lineRows = array_values($oldLines);
    } elseif ($isEdit) {
        $lineRows = $purchaseOrder->lines->map(fn ($line) => [
            'sku_id' => $line->sku_id,
            'qty' => $line->qty,
            'unit_id' => $line->unit_id,
            'unit_price' => $line->unit_price,
        ])->values()->all();
    } else {
        $lineRows = [[]];
    }

    if ($lineRows === []) {
        $lineRows = [[]];
    }
@endphp

<div class="line-items" data-line-items>
    <div class="line-items-header">
        <h3>Line items</h3>
        <button type="button" class="btn btn-secondary btn-sm" data-add-line>Add line</button>
    </div>
    <div data-line-rows>
        @foreach ($lineRows as $index => $line)
            @include('admin.inventory.partials.purchase_order_line', [
                'index' => $index,
                'line' => $line,
                'skus' => $skus ?? [],
                'units' => $units ?? [],
            ])
        @endforeach
    </div>
    <template data-line-template>
        @include('admin.inventory.partials.purchase_order_line', [
            'index' => 0,
            'line' => [],
            'skus' => $skus ?? [],
            'units' => $units ?? [],
        ])
    </template>
</div>