[Better Solution?]Category based form - php

Question

I am busy making a multi-shop shopping site like amazon.com, ebay, carousell.com etc...
Now when users create a listing I made a custom fields system that get the custom fields from a mysql table then outputs them into the form.
The Code:
Okay so first this is the listings table:
ID
list_title
list_brand
seller_id
1
Two sticks
Mr Sticks
1012
Then we have listings_meta which is where I store the custom fields like for a pillow it would be type of filling or for a stick it would be color of stick:
ID
listing_id
meta_key
meta_value
1
1
stick_color
brown
Now the meta key comes from a database table called [form_fields] which is linked the the categories like this
[form_fields]:
ID
meta_key
type
meta_link
1
stick_color
select
0
2
stick_length
input
0
3
rock_weight
input
0
4
brown
option
1
5
blue
option
1
And the category table[cats]:
ID
category
4
Sticks
5
Stones
Link custom fields and categories[cat_meta]:
ID
meta_id
cat_id
1
1
4
2
2
4
3
3
5
So now that you know how the items link with each other lets dive into the PHP code:
Now fist when a user clicks create product that will be given a popup asking which category they want to list the product thats done with a simple select query then they will be redirected to a new page called new_product.php?cat=[id of category from database ID]
new_product.php?cat=4
Now some of the fields are the same for all products they are the ones in listings table
But for custom fields its a bit more complex
:
<input type="text" name="list_title " placeholder="Title">
</br>
<input type="text" name="list_brand " placeholder="Brand">
</br>
<?php //get custom fields from custom_inputs table
//query the database for fields id and
$stmt = $conn->prepare("SELECT `meta_id ` FROM `cat_meta` WHERE `cat_id` = ?");
$stmt->bind_param("i", $_GET['cat']);
$stmt->execute();
$stmt_results = $stmt->get_result(); // get result
while($row_get = $stmt_results->fetch_assoc()){
$field_id[] = $row_get['meta_id ']; //store all id's in array
}
if(empty($field_id)){ //no custom field found in database
return 0;
}else{
foreach($field_id as $field_id){ //loop ID's to get multiple
$stmt = $conn->prepare("SELECT `meta_key `, `type ` FROM `form_fields` WHERE `ID` = ?");
$stmt->bind_param("i", $field_id);
$stmt->execute();
$stmt_results = $stmt->get_result(); // get result
while($row = $stmt_results->fetch_assoc()){
$field_name[] = $row['meta_key']; //get key aka title
$field_type[] = $row['type']; //get the type of input
}
}
}
foreach ($field_name as $index => $field) { //combine the type and meta key
$type = $field_type[$index];
if($type === "select"){ //field type is a select
echo '</br><select name="body['.$field.']">';
echo '<option selected Disabled value="">Select Option</option>';
//get options from `form_fields` linked to this meta_id
$stmt = $conn->prepare("SELECT `meta_key` FROM `form_fields` WHERE `meta_linked` = ? AND `field_type` = 'option'");
$stmt->bind_param("s", $field);
$stmt->execute();
$stmt_results = $stmt->get_result(); // get result
while($row = $stmt_results->fetch_assoc()){
echo '<option value='.$row['meta_key '].'>'.$row['meta_key'].'</option>';
}
echo '</select>';
}
if($type === "input"){ //field type is a user input
echo "<input name='body[$field]' placeholder='$field'>";
}
}
?>
Yes I know the code is very messy but I will clean it up before it is pushed but my issue is I feel like this seems over-complex/not efficient, Can anyone recommend a better way to build custom fields based on the category that was selected.
Also i do not include a lot of html and other php processing code as i dont think it needs to be included but if you need more info i will give it :)