itflow/user/ajax/ajax_item_edit.php

<?php

require_once '../includes/ajax_header.php';

$item_id = intval($_GET['id']);

$sql = mysqli_query($mysqli, "SELECT * FROM invoice_items WHERE item_id = $item_id LIMIT 1");
$row = mysqli_fetch_array($sql);
$item_name = nullable_htmlentities($row['item_name']);
$item_description = nullable_htmlentities($row['item_description']);
$item_quantity = floatval($row['item_quantity']);
$item_price = floatval($row['item_price']);
$item_created_at = nullable_htmlentities($row['item_created_at']);
$tax_id = intval($row['item_tax_id']);

// Generate the HTML form content using output buffering.
ob_start();
?>

<div class="modal-header">
    <h5 class="modal-title"><i class="fas fa-fw fa-edit mr-2"></i>Editing Line Item: <strong><?php echo $item_name; ?></strong></h5>
    <button type="button" class="close text-white" data-dismiss="modal">
        <span>&times;</span>
    </button>
</div>
<form action="post.php" method="post" autocomplete="off">
    <input type="hidden" name="item_id" value="<?php echo $item_id; ?>">
    
    <div class="modal-body bg-white">
        <div class="form-group">
            <label>Item <strong class="text-danger">*</strong></label>
            <div class="input-group">
                <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-box"></i></span>
                </div>
                <input type="text" class="form-control" name="name" maxlength="200" value="<?php echo $item_name; ?>" placeholder="Enter item name" required>
            </div>
        </div>

        <div class="form-row">
            <div class="col-sm">
                <div class="form-group">
                    <label>Quantity <strong class="text-danger">*</strong></label>
                    <div class="input-group">
                        <div class="input-group-prepend">
                            <span class="input-group-text"><i class="fa fa-fw fa-balance-scale"></i></span>
                        </div>
                        <input type="text" class="form-control" inputmode="numeric" pattern="[0-9]*\.?[0-9]{0,2}" name="qty" value="<?php echo number_format($item_quantity, 2); ?>" placeholder="0.00" required>
                    </div>
                </div>
            </div>

            <div class="col-sm">
                <div class="form-group">
                    <label>Price <strong class="text-danger">*</strong></label>
                    <div class="input-group">
                        <div class="input-group-prepend">
                            <span class="input-group-text"><i class="fa fa-fw fa-dollar-sign"></i></span>
                        </div>
                        <input type="text" class="form-control" inputmode="numeric" pattern="-?[0-9]*\.?[0-9]{0,2}" name="price" value="<?php echo number_format($item_price, 2, '.', ''); ?>" placeholder="0.00" required>
                    </div>
                </div>
            </div>
        </div>

        <div class="form-group">
            <label>Description</label>
            <div class="input-group">
                <textarea class="form-control" rows="5" name="description" placeholder="Enter a description"><?php echo $item_description; ?></textarea>
            </div>
        </div>

        <div class="form-group">
            <label>Tax <strong class="text-danger">*</strong></label>
            <div class="input-group">
                <div class="input-group-prepend">
                    <span class="input-group-text"><i class="fa fa-fw fa-piggy-bank"></i></span>
                </div>
                <select class="form-control select2" name="tax_id" required>
                    <option value="0">No Tax</option>
                    <?php 
                        $taxes_sql = mysqli_query($mysqli, "SELECT * FROM taxes WHERE (tax_archived_at > '$item_created_at' OR tax_archived_at IS NULL) ORDER BY tax_name ASC"); 
                        while ($row = mysqli_fetch_array($taxes_sql)) {
                            $tax_id_select = intval($row['tax_id']);
                            $tax_name = nullable_htmlentities($row['tax_name']);
                            $tax_percent = floatval($row['tax_percent']);
                    ?>
                        <option <?php if ($tax_id_select == $tax_id) { echo "selected"; } ?> value="<?php echo $tax_id_select; ?>"><?php echo "$tax_name $tax_percent%"; ?></option>
                    <?php
                        }
                    ?>
                </select>
            </div>
        </div>
    </div>

    <div class="modal-footer bg-white">
        <button type="submit" name="edit_item" class="btn btn-primary text-bold"><i class="fas fa-check mr-2"></i>Save</button>
        <button type="button" class="btn btn-light" data-dismiss="modal"><i class="fas fa-times mr-2"></i>Cancel</button>
    </div>
</form>

<?php
require_once "../includes/ajax_footer.php";