private $id;
private $username;
private $email;
private $firstName;
private $lastName;
private $uniqueURLId;
private $password;
private $mostRecentProject;
private $previousProject;
private $lastProject;

private $date;

/**
 * User_test constructor.
 * @param $user
 */
public function __construct($user)
{
    $this->id = $user['USR_UserId']; //required
    $this->username = $user['USR_Username']; //required
    $this->email = $user['USR_Email']; //required
    $this->firstName = $user['USR_FirstName']; //required
    $this->lastName = $user['USR_LastName']; //required
    $this->uniqueURLId = $user['USR_UniqueURLId'];
    $this->password = $user['USR_Password']; //required
    $this->mostRecentProject = $user['USR_ProjectMostRecent'];
    $this->previousProject = $user['USR_ProjectPrevious'];
    $this->lastProject = $user['USR_ProjectLast'];
}

/**
 * checkURLId
 * Checks if UniqueURLId is null and sets it if it is.
 *
 * @param   int         $projectId          Integer ID referencing specific project to be concatenated onto the URLId
 */
private function checkURLId($projectId) {
    if(is_null($this->uniqueURLId)) {
        $db = new DBManager();
        $this->uniqueURLId = RandomObjectGeneration::random_str(15) . $projectId;
        $sql = "UPDATE gaig_users.users SET USR_UniqueURLId=? WHERE USR_UserId=?;";
        $bindings = array($this->uniqueURLId,$this->id);
        $db->query($sql,$bindings);
    }
}

/**
 * pushUser
 * Pushes $this onto the provided array if it is valid.
 *
 * @param   array                   $validUsers             Array of User_test objects
 * @param   int                     $periodInWeeks          Period to check in validation of user
 * @param   TemplateConfiguration   $templateConfig         Template Configuration for validation
 */
public function pushUser($validUsers, $periodInWeeks, TemplateConfiguration $templateConfig) {
    try {
        $this->checkURLId($templateConfig->getProjectId());
        if($this->isValid($periodInWeeks,$templateConfig)) {
            $validUsers[] = $this;
        }
    } catch(Exception $e) {

    }
}

/**
 * isValid
 * Verifies the user is valid according to the verification algorithm defined in the check... functions.
 *
 * @param   int                     $periodInWeeks          Period to check in validation of user
 * @param   TemplateConfiguration   $templateConfig         Template Configuration for validation
 * @return  bool
 */
private function isValid($periodInWeeks, TemplateConfiguration $templateConfig) {
    try {
        $db = new DBManager();
        $sql = "
            SELECT MAX(SML_SentTimestamp) AS 'timestamp_check'
            FROM gaig_users.sent_email
            WHERE SML_UserId = ? AND SML_ProjectName = ?;";
        $bindings = array($this->id,$this->mostRecentProject);
        $data = $db->query($sql,$bindings);
        if($data->rowCount() > 0) {
            $result = $data->fetch();
            $this->date = date('Y-m-d',strtotime('-' . $periodInWeeks . ' weeks')) . ' 00:00:00';
            if($this->checkPeriod($this->date,$result['timestamp_check'])) {
                return true;
            }
            $sql = "SELECT * FROM gaig_users.projects WHERE PRJ_ProjectId = ?;";
            $data = $db->query($sql,array($this->mostRecentProject));
            $mostRecentProj = new Project($data->fetch());
            $newComplexity = $templateConfig->getTemplateComplexityType();
            $newTarget = $templateConfig->getTemplateTargetType();
            if($this->checkMRP($mostRecentProj,$newComplexity,$newTarget)) {
                return false;
            }
            $data = $db->query($sql,array($this->previousProject));
            $previousProj = new Project($data->fetch());
            if($this->checkPP($mostRecentProj,$previousProj,$newComplexity)) {
                return false;
            }
            $data = $db->query($sql,array($this->lastProject));
            $lastProj = new Project($data->fetch());
            if($this->checkLP($mostRecentProj,$previousProj,$lastProj,$newTarget)) {
                return false;
            }
        }
        return true;
    } catch(Exception $e) {
        //unsure how to manage any exceptions thrown yet, if at all. further design to come
    }
}

/**
 * checkPeriod - Verification Algorithm
 * Verifies if the period is outside of periodInWeeks zone.
 *
 * @param   string          $date               Date in format 'Y-m-d h:i:s'
 * @param   string          $timestamp          Date retrieved from PDOStatement
 * @return  bool
 */
private function checkPeriod($date,$timestamp) {
    return $timestamp <= $date;
}

/**
 * checkMRP - Verification Algorithm
 * Checks the Most Recent Project to see if identical.
 *
 * @param   Project         $mrp            Project object representing the Most Recent Project
 * @param   string          $complexity     Complexity type of requested template
 * @param   string          $target         Target type of requested template
 * @return  bool
 */
private function checkMRP(Project $mrp, $complexity, $target) {
    return $complexity == $mrp->getTemplateComplexityType() &&
        $target == $mrp->getTemplateTargetType();
}

/**
 * checkPP - Verification Algorithm
 * Checks the Previous Project and Most Recent Project for identical complexity type.
 *
 * @param   Project         $mrp            Project object representing the Most Recent Project
 * @param   Project         $pp             Project object representing the Previous Project
 * @param   string          $complexity     Complexity type of requested template
 * @return  bool
 */
private function checkPP(Project $mrp, Project $pp, $complexity) {
    return !is_null($pp) &&
        $complexity == $mrp->getTemplateComplexityType() &&
        $complexity == $pp->getTemplateComplexityType();
}

/**
 * checkLP - Verification Algorithm
 * Checks the Last Project, Previous Project, and Most Recent Project for identical target type.
 *
 * @param   Project         $mrp            Project object representing the Most Recent Project
 * @param   Project         $pp             Project object representing the Previous Project
 * @param   Project         $lp             Project object representing the Last Project
 * @param   string          $target         Target type of requested template
 * @return  bool
 */
private function checkLP(Project $mrp, Project $pp, Project $lp, $target) {
    return !is_null($lp) &&
        !is_null($pp) &&
        $target == $mrp->getTemplateTargetType() &&
        $target == $pp->getTemplateTargetType() &&
        $target == $lp->getTemplateTargetType();
}

public function getLastName() {
    return $this->lastName;
}

public function getUsername() {
    return $this->username;
}

public function getUniqueURLId() {
    return $this->uniqueURLId;
}

public function getEmail() {
    return $this->email;
}

/**
 * getValidUsers
 * Retrieves all users from the database and validates them through the User_test object.
 *
 * @param   array           $returnUsers            Array of User_test objects
 * @param   int             $periodInWeeks          Period to check for instant sending of email
 * @return  array
 */
public function getValidUsers($returnUsers, $periodInWeeks) {
    $db = new DBManager();
    $sql = "SELECT * FROM gaig_users.users;";
    $users = $db->query($sql,array(),array('PDO::ATTR_CURSOR'),array('PDO::CURSOR_SCROLL'));
    $usersIterator = new PDOIterator($users);
    foreach($usersIterator as $user) {
        $tempUser = new User_Test($user);
        $tempUser->pushUser($returnUsers,$periodInWeeks,$this);
    }
    return $returnUsers;
}

/**
 * sendEmail
 * Function mapped to Laravel route. Defines variable arrays and calls Email Class executeEmail.
 *
 * @param   Request         $request            Request object passed via AJAX from client.
 */
public function sendEmail(Request $request) {
    try {
        $templateConfig = new TemplateConfiguration(
            array(
                'templateName'=>$request->input('emailTemplate'),
                'companyName'=>$request->input('companyName'),
                'projectName'=>$request->input('projectData')['projectName'],
                'projectId'=>intval($request->input('projectData')['projectId'])
            )
        );

        $periodInWeeks = 4;
        $users = array();
        $emailConfig = new EmailConfiguration(
            array(
                'host'=>$request->input('hostName'),
                'port'=>$request->input('port'),
                'authUsername'=>$request->input('username'),
                'authPassword'=>$request->input('password'),
                'fromEmail'=>$request->input('fromEmail'),
                'subject'=>$request->input('subject'),
                'users'=>$templateConfig->getValidUsers($users,$periodInWeeks)
            )
        );

        Email::executeEmail($emailConfig,$templateConfig);
    } catch(ConfigurationException $ce) {
        //will be doing something here - what still has yet to be defined (likely just log the exception)
    } catch(EmailException $ee) {
        //will be doing something here - what still has yet to be defined (likely just log the exception)
    }
}

private static $templateConfig;
private static $emailConfig;

/**
 * executeEmail
 * Public-facing method to send an email to a database of users if they are a valid recipient.
 *
 * @param   EmailConfiguration          $emailConfig            Email Configuration object containing required information to send an email
 * @param   TemplateConfiguration       $templateConfig         Template Configuration object containing required information to build a template
 * @throws  EmailException                                      Custom Exception to embody any exceptions thrown in this class
 */
public static function executeEmail(
    EmailConfiguration $emailConfig,
    TemplateConfiguration $templateConfig)
{
    self::setTemplateConfig($templateConfig);
    self::setEmailConfig($emailConfig);

    try {
        foreach($emailConfig->getUsers() as $user) {
            self::sendEmail($user);
            self::updateUserProjects($user);
        }
    } catch(Exception $e) {
        throw new EmailException(__CLASS__ . ' Exception',0,$e);
    }
}

/**
 * updateUserProjects
 * Updates the user with the newest project and rotates the old projects down one.
 *
 * @param   array           $user           User array extracted from PDOStatement
 */
private function updateUserProjects($user) {
    $db = new DBManager();
    $sql = "UPDATE gaig_users.users SET USR_ProjectMostRecent=?, USR_ProjectPrevious=?,
                USR_ProjectLast=? WHERE USR_Username=?;";
    $bindings = array(self::$templateConfig->getProjectName(),
        $user['USR_ProjectMostRecent'],
        $user['USR_ProjectPrevious'],
        $user['USR_Username']
    );
    $db->query($sql,$bindings);
}

/**
 * sendEmail
 * Sends them an email to the specified user.
 *
 * @param   User_test           $user           User object
 * @throws  FailureException
 */
private static function sendEmail($user) {
    $templateData = array(
        'companyName'=>self::$templateConfig->getCompanyName(),
        'projectName'=>self::$templateConfig->getProjectName(),
        'projectId'=>self::$templateConfig->getProjectId(),
        'lastName'=>$user->getLastName(),
        'username'=>$user->getUsername(),
        'urlId'=>$user->getUniqueURLId()
    );
    $subject = self::$emailConfig->getSubject();
    $from = self::$emailConfig->getFromEmail();
    $to = $user->getEmail();
    $mailResult = Mail::send(
        ['html' => self::$templateConfig->getTemplate()],
        $templateData,
        function($m) use ($from, $to, $subject) {
            $m->from($from);
            $m->to($to)
                ->subject($subject);
        }
    );
    if(!$mailResult) {
        throw new FailureException('Email failed to send to ' . $to . ', from ' . $from);
    }
}

private static function setTemplateConfig(TemplateConfiguration $templateConfig) {
    self::$templateConfig = $templateConfig;
}

private static function setEmailConfig(EmailConfiguration $emailConfig) {
    self::$emailConfig = $emailConfig;
}

class RandomObjectGeneration
{
/**
 * random_str
 * Generates a random string.
 *
 * @param   int         $length         Length of string to be returned
 * @param   string      $keyspace       Allowed characters to be used in string
 * @return  string
 */
public static function random_str($length, $keyspace = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ')
{
    if(is_null($length) || !is_numeric($length)) {
        throw new Exception();
    }
    $str = '';
    $max = mb_strlen($keyspace) - 1;
    for ($i = 0; $i < $length; ++$i) {
        $str .= $keyspace[random_int(0, $max)];
    }
    return $str;
}
}