opensourcepos/app/Views/configs/invoice_config.php

<?php
/**
 * @var array $invoice_type_options
 * @var array $line_sequence_options
 * @var array $config
 */
?>

<?= form_open('config/saveInvoice/', ['id' => 'invoice_config_form', 'class' => 'form-horizontal']) ?>
    <div id="config_wrapper">
        <fieldset id="config_info">

            <div id="required_fields_message"><?= lang('Common.fields_required_message') ?></div>
            <ul id="invoice_error_message_box" class="error_message_box"></ul>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.invoice_enable'), 'invoice_enable', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-1">
                    <?= form_checkbox([
                        'name'    => 'invoice_enable',
                        'value'   => 'invoice_enable',
                        'id'      => 'invoice_enable',
                        'checked' => $config['invoice_enable'] == 1
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.invoice_type'), 'invoice_type', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-3">
                    <?= form_dropdown(
                        'invoice_type',
                        $invoice_type_options,
                        $config['invoice_type'],
                        'class="form-control input-sm"'
                    ) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.recv_invoice_format'), 'recv_invoice_format', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-2">
                    <?= form_input([
                        'name'  => 'recv_invoice_format',
                        'id'    => 'recv_invoice_format',
                        'class' => 'form-control input-sm',
                        'value' => $config['recv_invoice_format']
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.invoice_default_comments'), 'invoice_default_comments', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-5">
                    <?= form_textarea([
                        'name'  => 'invoice_default_comments',
                        'id'    => 'invoice_default_comments',
                        'class' => 'form-control input-sm',
                        'value' => $config['invoice_default_comments']
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.invoice_email_message'), 'invoice_email_message', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-5">
                    <?= form_textarea([
                        'name'  => 'invoice_email_message',
                        'id'    => 'invoice_email_message',
                        'class' => 'form-control input-sm',
                        'value' => $config['invoice_email_message']
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.line_sequence'), 'line_sequence', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-2">
                    <?= form_dropdown(
                        'line_sequence',
                        $line_sequence_options,
                        $config['line_sequence'],
                        'class="form-control input-sm"'
                    ) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.sales_invoice_format'), 'sales_invoice_format', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-2">
                    <?= form_input([
                        'name'  => 'sales_invoice_format',
                        'id'    => 'sales_invoice_format',
                        'class' => 'form-control input-sm',
                        'value' => $config['sales_invoice_format']
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.last_used_invoice_number'), 'last_used_invoice_number', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-2">
                    <?= form_input([
                        'type'  => 'number',
                        'name'  => 'last_used_invoice_number',
                        'id'    => 'last_used_invoice_number',
                        'class' => 'form-control input-sm required',
                        'value' => $config['last_used_invoice_number']
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.sales_quote_format'), 'sales_quote_format', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-2">
                    <?= form_input([
                        'name'  => 'sales_quote_format',
                        'id'    => 'sales_quote_format',
                        'class' => 'form-control input-sm',
                        'value' => $config['sales_quote_format']
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.last_used_quote_number'), 'last_used_quote_number', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-2">
                    <?= form_input([
                        'type'  => 'number',
                        'name'  => 'last_used_quote_number',
                        'id'    => 'last_used_quote_number',
                        'class' => 'form-control input-sm required',
                        'value' => $config['last_used_quote_number']
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.quote_default_comments'), 'quote_default_comments', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-5">
                    <?= form_textarea([
                        'name'  => 'quote_default_comments',
                        'id'    => 'quote_default_comments',
                        'class' => 'form-control input-sm',
                        'value' => $config['quote_default_comments']
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.work_order_enable'), 'work_order_enable', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-1">
                    <?= form_checkbox([
                        'name'    => 'work_order_enable',
                        'value'   => 'work_order_enable',
                        'id'      => 'work_order_enable',
                        'checked' => $config['work_order_enable'] == 1
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.work_order_format'), 'work_order_format', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-2">
                    <?= form_input([
                        'name'  => 'work_order_format',
                        'id'    => 'work_order_format',
                        'class' => 'form-control input-sm',
                        'value' => $config['work_order_format']
                    ]) ?>
                </div>
            </div>

            <div class="form-group form-group-sm">
                <?= form_label(lang('Config.last_used_work_order_number'), 'last_used_work_order_number', ['class' => 'control-label col-xs-2']) ?>
                <div class="col-xs-2">
                    <?= form_input([
                        'type'  => 'number',
                        'name'  => 'last_used_work_order_number',
                        'id'    => 'last_used_work_order_number',
                        'class' => 'form-control input-sm required',
                        'value' => $config['last_used_work_order_number']
                    ]) ?>
                </div>
            </div>

            <?= form_submit([
                'name'  => 'submit_invoice',
                'id'    => 'submit_invoice',
                'value' => lang('Common.submit'),
                'class' => 'btn btn-primary btn-sm pull-right'
            ]) ?>

        </fieldset>
    </div>
<?= form_close() ?>

<script type="text/javascript">
    // Validation and submit handling
    $(document).ready(function() {
        var enable_disable_invoice_enable = (function() {
            var invoice_enabled = $("#invoice_enable").is(":checked");
            var work_order_enabled = $("#work_order_enable").is(":checked");
            $("#sales_invoice_format, #recv_invoice_format, #invoice_default_comments, #invoice_email_message, select[name='invoice_type'], #sales_quote_format, select[name='line_sequence'], #last_used_invoice_number, #last_used_quote_number, #quote_default_comments, #work_order_enable, #work_order_format, #last_used_work_order_number").prop("disabled", !invoice_enabled);
            if (invoice_enabled) {
                $("#work_order_format, #last_used_work_order_number").prop("disabled", !work_order_enabled);
            } else {
                $("#work_order_enable").attr('checked', false);
            }
            return arguments.callee;
        })();

        var enable_disable_work_order_enable = (function() {
            var work_order_enabled = $("#work_order_enable").is(":checked");
            var invoice_enabled = $("#invoice_enable").is(":checked");
            if (invoice_enabled) {
                $("#work_order_format, #last_used_work_order_number").prop("disabled", !work_order_enabled);
            }
            return arguments.callee;
        })();

        $("#invoice_enable").change(enable_disable_invoice_enable);

        $("#work_order_enable").change(enable_disable_work_order_enable);

        $("#invoice_config_form").validate($.extend(form_support.handler, {

            errorLabelContainer: "#invoice_error_message_box",

            submitHandler: function(form) {
                $(form).ajaxSubmit({
                    beforeSerialize: function(arr, $form, options) {
                        $("#sales_invoice_format, #sales_quote_format, #recv_invoice_format, #invoice_default_comments, #invoice_email_message, #last_used_invoice_number, #last_used_quote_number, #quote_default_comments, #work_order_enable, #work_order_format, #last_used_work_order_number").prop("disabled", false);
                        return true;
                    },
                    success: function(response) {
                        $.notify({
                            message: response.message
                        }, {
                            type: response.success ? 'success' : 'danger'
                        })
                        // Set back disabled state
                        enable_disable_invoice_enable();
                        enable_disable_work_order_enable();
                    },
                    dataType: 'json'
                });
            }
        }));
    });
</script>