<?php
// ----------------------------------------------------------------------------
// altered_tag.php
// Contains the Altered_Tag class definition.
// ----------------------------------------------------------------------------

require_once '/projects/lupp/2-1-devel/www/common/xml_handler.php';
// require_once '../../xml_handler.php';

// ----------------------------------------
// The Altered_Tag class contains all the data representing an
// alteration to a result and meta data for the xml report.
// ----------------------------------------
        
class Altered_Tag {
    
    // ----------------------------------------
    // Instance variables
    // ----------------------------------------
    // Attributes
    private $date;
    private $by;
    private $to_state; // failed, passed, autofail, autopass
    private $auto_to_state; // failed, passed, autofail, autopass

    // Variables to handle storing data on file 
    private $is_new;
    
    // ----------------------------------------
    // Constructor
    //
    // The only "true" constructor which is always the one
    // called. Works as a filter, and checks the arg count to see
    // which "fake constructor" should be called.
    // ----------------------------------------
    public function __construct() {

        $args = func_get_args();
        $arg_count = func_num_args();

        if (method_exists($this, $function = '__construct'.$arg_count)) {
            call_user_func_array(array($this, $function), $args);
        }
    }
    
    // ----------------------------------------
    // Constructor
    //
    // Initiates instance variables and creates classes based
    // on the xml data received.
    //
    // Arguments:
    // $xml_data is an xml data object supposed to contain relevant
    // data retrieved from the char_students.year-semester file(s).
    // ----------------------------------------
    public function __construct1($xml_data) {

        $this->date = $xml_data->getAttribute('date');
        $this->by = $xml_data->getAttribute('by');

        if ( $xml_data->hasAttribute('tostate') ) {
            $this->to_state = $xml_data->getAttribute('tostate');
        }
        
        if ( $xml_data->hasAttribute('autotostate') ) {
            $this->auto_to_state = $xml_data->getAttribute('autotostate');
        }
  
    }

    // ----------------------------------------
    // Constructor
    //
    // Initiates the instance based on extracted data instead of an
    // xml object.
    //
    // Arguments:
    // $date is the date of the alteration
    // $by is the user making the alteration
    // $to_state is the new state for the result sub part
    // ----------------------------------------
    public function __construct4($date,
                                 $by,
                                 $to_state,
                                 $auto_to_state) {

        $this->is_new = true;
        $this->date = $date;
        $this->by = $by;
        $this->to_state = $to_state;
        $this->auto_to_state = $auto_to_state;
    }
    
    // ----------------------------------------
    // get_date
    //
    // Returns the date of the alteration.
    // ----------------------------------------
    public function get_date() {

        return $this->date;
    }
    
    // ----------------------------------------
    // get_altered_by
    //
    // Returns who altered the result.
    // ----------------------------------------
    public function get_altered_by() {

        return $this->by;
    }

    // ----------------------------------------
    // get_auto_to_state
    //
    // Returns the new auto state for this alteration.
    // ----------------------------------------
    public function get_auto_to_state() {

        return $this->auto_to_state;
    }

    // ----------------------------------------
    // get_to_state
    //
    // Returns the new state for this alteration.
    // ----------------------------------------
    public function get_to_state() {

        return $this->to_state;
    }
    
    // ----------------------------------------
    // is_new
    //
    // Returns a boolean indicating whether the sub part is new to
    // this student.
    // ----------------------------------------
    public function is_new() {

        return $this->is_new;
    }

    // ----------------------------------------
    // save_results_to_file
    //
    // Stores the results for this altered tag on the given
    // file. We know the student exists in active students for this
    // course.
    //
    // Arguments:
    //   $xml_document is the DOMDocument in which to store the changes.
    //   $sub_elem the sub part xml element to append results to.
    //
    // Returns true if successfully saved, false otherwise, to handle
    // errors outside.
    // ----------------------------------------
    public function save_results_to_file($xml_document,
                                         $sub_elem) {

        // An altered tag that has been added is always new, we never
        // modify a tag, so we create a new one.
        $tag_elem = $xml_document->createElement('altered');
        $tag_elem->setAttribute('date', $this->date);
        $tag_elem->setAttribute('by', $this->by);

        // ----------
        // Check the optional attributes and store them if they
        // have a value.
        // ----------
        if ( isset($this->to_state) and ! empty($this->to_state) ) {
            $tag_elem->setAttribute('tostate', $this->to_state);
        }
        
        if ( isset($this->auto_to_state) and ! empty($this->auto_to_state) ) {
            $tag_elem->setAttribute('autotostate', $this->auto_to_state);
        }

        $sub_elem->appendChild($tag_elem);
    }
    
    // ----------------------------------------
    // print_dump
    //
    // Print function for debugging / testing.
    // ----------------------------------------
    public function print_dump() {
        
        print "\t\t\t\tAltered tag date: " . $this->date
                                         . ", by: " . $this->by
                                         . ", tostate: " . $this->to_state
                                         . ", toautostate: " . $this->auto_to_state
                                         . "\n";
        
    }
    
    // ----------------------------------------
    // End of Altered_Tag class definition
    // ----------------------------------------
}

// ----------------------------------------------------------------------------
?>