Add and update data in json file with php function - php

Question

I want to control the data coming with the post with the function and update it if there is data, and add it if there is no data.
I am updating and adding with the following codes, but in the second addition, it both updates the existing information and adds the same information again.
I wonder where am I doing the mistake, can you help me?
$data = array('sure'=>'1', 'id'=>'38138373','t'=>'6', 's'=>'s3', 'p'=>'6');
function updateCart($data,$user_id,$cartid){
$updateCart = [];
$carts = getCart($user_id,$cartid);
foreach ($carts as $i => $cart) {
if($cart['id'] == $data['id'] && $cart['t'] == $data['t'] && $cart['s'] == $data['s']) {
$newp = $cart['p']+$data['p'];
$carts[$i]['p'] = $newp;
} else {
$carts[] = $data;
}
}
putJson($carts,$user_id,$cartid);
}
/* $carts */
[
{
"sure": "1",
"id": "38138373",
"t": "8",
"s": "s5",
"p": 6
},{
"sure": "1",
"id": "38138373",
"t": "6",
"s": "s3",
"p": 9
}
]
This is the result after the function.
[
{
"sure": "1",
"id": "38138373",
"t": "8",
"s": "s5",
"p": 6
},
{
"sure": "1",
"id": "38138373",
"t": "6",
"s": "s3",
"p": 9
},
{
"sure": "1",
"id": "38138373",
"t": "6",
"s": "s3",
"p": 12
},
{
"sure": "1",
"id": "38138373",
"t": "6",
"s": "s3",
"p": "3"
}
]
The file should be like this
[
{
"sure": "1",
"id": "38138373",
"t": "8",
"s": "s5",
"p": 6
},
{
"sure": "1",
"id": "38138373",
"t": "6",
"s": "s3",
"p": 15
}
]

Answer 1

The below code should work for you:
function updateCart($data, $user_id, $cartid){
$updateCart[] = $data;
$carts = getCart($data, $user_id, $cartid);
foreach ($carts as $cart) {
if( ($cart['id'] == $data['id']) && ($cart['t'] == $data['t']) &&
($cart['s'] == $data['s'])) {
$cart['p'] = $data['p'] + $cart['p'];
$data['p'] = $cart['p'];
$updateCart[0] = $cart;
}
$updateCart[] = $cart;
}
$updateCart[] = array_shift($updateCart);
return putJson($updateCart, $user_id, $cartid);
}
Let me know if this is okay. You should try and add break points at key stages in your code, to examine if the output is correct. How you do this is up to you, and your choices will vary depending on the framework you use etc. You could start with reading the PHP documentation about var_dump here.