comparing arrays of objects

<?php

$users = array(
    array(
        'user_account_nbr' => 1234,
        'email'=> 'user@example.com',
        'login' => 'user',
        'last_seen' => 2016
        ),
    array(
        'user_account_nbr' => 12345,
        'email'=> 'user@example.com',
        'login' => 'user2',
        'last_seen' => 2015
        ),
    array(
        'user_account_nbr' => 123456,
        'email'=> 'user@example.com',
        'login' => NULL,
        'last_seen' => 2014
        ),
    array(
        'user_account_nbr' => 1234567,
        'email'=> 'test@example.com',
        'login' => 'test',
        'last_seen' => 2013
        ),
    array(
        'user_account_nbr' => 12345678,
        'email'=> 'user@example.com',
        'login' => NULL,
        'last_seen' => 2012
        ),
    array(
        'user_account_nbr' => 123456789,
        'email'=> 'nologin@example.com',
        'login' => NULL,
        'last_seen' => 1998
        ),
    array(
        'user_account_nbr' => 12345678910,
        'email'=> 'nologin@example.com',
        'login' => NULL,
        'last_seen' => 1950
        )
    );
    $skip = array();                                            // Blank array to store checked entries so they can be skipped
    $haslogin = FALSE;                                          // Variable we will use later to check if an array of matching email users contains logins or if they are all null

for ($i = 0; $i <= (count($users)-1); $i++){                    // Loop through user array
    if (in_array("$i", $skip) == TRUE){                         // Check if current user has been already checked
                                                                // Do nothing as user has already been checked
    }
    else {                                                      // User not found in $skip array, continue with if statement
        $temp = array();                                        // Temporary array to store key values for users that share the same e-mail as the current user in the loop
        for ($x = 0; $x <= (count($users)-1); $x++){            // Loop back through the array, with this loop we are goign to check the emails to see if they match current selected user in the parent loop
            if ($users[$i]['email'] === $users[$x]['email']){   // Check if current user of child loop shares the same e-mail as the current user in the parent loop
                array_push($temp, $x);                          // Push the key of the user of the child loop to the $temp array
            };
        };
    foreach($temp as $value){                                   // Loop each user that has been added to the $temp array (These users all have matching emails to the currently selected user in the top parent loop)
        if ($users[$value]["login"] !== NULL){                  // Check if the user has a value for login.
            $haslogin = TRUE;                                   // If one of the users looped has a value for login, variable will be set to true.
        };
    };

    if ($haslogin == TRUE){                                     // If the last loop found that one or more of the users in the $temp array contain a value for login
        foreach($temp as $value){                               // Loop backthrough the $temp array
            if ($users[$value]["login"] == NULL){               // Check if the user does not have a value for login
                $users[$value]["email"] = NULL;                 // Set the email value of the user(s) with no value for login to NULL
            };
        };
    }
    else {                                                      // Else if haslogin returned FALSE
        $date = 0;                                              // Set variable for comparing last login date
        $latest = NULL;                                         // Set varaible for storing the key of the the user with the latest login.
        foreach($temp as $value){                               // Loop backthrough the $temp array
            if ($users[$value]["last_seen"] > $date){           // If current selected user last seen date greater then $date
                $date = $users[$value]["last_seen"];            // Set $date to the greater value of the current selected user
                $latest = $value;                               // Set latest to the key number of the current selected user
            };
        };
        foreach($temp as $value){                               // Loop backthrough the $temp array
            if ($value !== $latest){                            // If user is not the user with the most recent visit date
                $users[$value]["email"] = NULL;                 // Set the email value of the user(s) with not the latest visit date ot NULL
            };
        };

    };
foreach($temp as $value){                                       // Loop backthrough the $temp array
    array_push($skip, $value);                                  // Add the key values of the users we have just checked to the $skip array so that the main parent loop skips past them.
};
unset($temp);                                                   // Unset $temp array so it can be used on the next user in the main parent loop
$haslogin = FALSE;                                              // Set $haslogin back to FALSE so it is not already triggered on the next user in the main parent loop
};

};

print "<pre>";
print_r($users);                                    // Print User array to see changes
print "</pre>";