Allow a client to edit a products custom field from productdetails page

[whattheserver]

I'm looking to basically allow editing of a custom field for a product.

I would like to essentially clone how the change password function works but with just one input field and when it saves it updates the custom field and runs a custom function.

I have a function and clientareacustombutton which opens a macaddy.tpl file with form input. It seems like the documentation and examples are scarse and missing vital example.

function from the module

function freeradius_ClientAreaCustomButtonArray() {
    $buttonarray = array(
     "Change MacAddress" => "changemac",
    );
    return $buttonarray;
}

function freeradius_changemac($vars) {
    return array(
        'templatefile' => 'macaddy',
        'breadcrumb' => array(
            'stepurl.php?action=this&var=that' => 'Change MacAddress',
        ),
        'vars' => $params
    );
    $CurrentMacAddress = $params['customfields']['MacAddress'];

    if($_POST['newmac']) {

    $username = $params["username"];
    $password = $params["password"];
    $newmacaddy = $_POST["newmac"];
    
    

    shell_exec("/some/path/to/perfect_dark_setup.sh update $username $newmacaddy"); //returns a macaddress as a string like 'c2:eb:e8:31:98:01'

        Capsule::table('tblcustomfieldsvalues')
            ->where('relid', '=', $params["serviceid"])
            ->where('fieldid', '=', 1)
            ->update(array(
                'value' => $newmacaddy,
            ));

}
}

macaddy.tpl
 

<form method="post" action="clientarea.php?action=productdetails">
<input type="hidden" name="id" value="{$serviceid}" />
<input type="submit" value="« Back to Service" class="btn" style="float: right;" />
</form>

    <div class="tab-pane fade in" id="tabChangeMacAddy">

        <h3>Change MacAddress</h3>

        
        <form class="form-horizontal" method="post" action="/clientarea.php?action=productdetails" role="form">
            <input type="hidden" name="id" value="{$serviceid}" />
            <input type="hidden" name="a" value="changemac" />
            <div id="newMacAddy" class="form-group has-feedback">
                <label for="inputNewMacAddy" class="col-sm-4 control-label">New MacAddress</label>
                <div class="col-sm-5">
                    <input type="text" class="form-control" id="inputNewMacAddy" name="newmac" autocomplete="off" value="{$newmac}" />
                    <span class="form-control-feedback glyphicon"></span>
                    <br />

            <div class="form-group">
                <div class="col-sm-offset-6 col-sm-6">
                    <input class="btn btn-primary" type="submit" value="Save Changes" />
                    <input class="btn" type="reset" value="Cancel" />
                </div>
            </div>

        </form>

How it looks currently:

After submitting it takes me back to the main product details page and the custom function and update are not executed.

I reviewed both the below pages and all tpl and templates I could find that were not encoded for reference, but was unable to determine if form input is not being passed back

https://developers.whmcs.com/provisioning-modules/custom-functions/

https://developers.whmcs.com/provisioning-modules/client-area-output/

Probably missing something simple here. Any advice or examples would be helpful.  It seems like allowing clients to be able to edit a product's custom field should not be so difficult. Especially since the functionality exists on custom client fields just not implemented on product custom fields 😕

Hoping someone else who has already done this can point me in the right direction.

Thanks

 

Edited December 5, 2019 by whattheserver