<?php
// ----------------------------------------------------------------------------
// all_students.php
// Contains the All_Students class definition.
// ----------------------------------------------------------------------------

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


// ----------------------------------------
// The All_Students class contains the data for a student in
// the active students category.
//----------------------------------------
class All_Students {

    // ----------------------------------------
    // Instance variables
    // ----------------------------------------
    // Sub tags
    private $groups;

    // Attributes
    private $course_code;
    private $faculty;
    
    // File / file contents to retain
    private $file_path;
    private $comments;
    
    // ----------------------------------------
    // Constructor
    //
    // Initiates instance variables and creates classes based
    // on the xml data received.
    //
    // Arguments:
    // $course_code is the course code for the course in question
    // ----------------------------------------
    public function __construct($course_code) {

        $this->course_code = $course_code;
        $this->groups = array();

        // Get an xml handler and begin extracting data
        $handler = $this->get_all_students_xml_handler();
        $groups_data = $handler->get_node_array('/students/group');
        
        foreach ( $groups_data as $group ) {
            $this->groups[] = new Student_Groups($group);
        }
    }

    // ----------------------------------------
    // get_course_code
    //
    // Returns the course code for this object.
    // ----------------------------------------
    public function get_course_code() {
        return $this->course_code;
    }
    
    // ----------------------------------------
    // get_student_by_uid
    //
    // Returns the desired student, null if not found.
    //
    // Arguments:
    // $uid is the student's uid
    // ----------------------------------------
    public function get_student_by_uid($uid) {

        // ----------
        // Look through all the groups in an attempt to find the
        // student.
        // ----------
        foreach ( $this->groups as $group ) {
            $result = $group->get_student_by_uid($uid);
            if ( isset($result) ) {
                // Found it!
                return $result;
            }
        }

        // No such student found
        return null;
    }
     
    // ----------------------------------------
    // get_groups
    //
    // Returns an array of all groups.
    // ----------------------------------------
    public function get_groups() {

        return $this->groups;
    }

    // ----------------------------------------
    // get_faculty
    //
    // Returns the faculty for this course.
    // ----------------------------------------
    public function get_faculty() {

        return $this->faculty;
    }

    // ----------------------------------------
    // get_group_by_first_reg
    //
    // Returns the group of students with registration matching
    // $first_reg, null if no such group exists.
    //
    // Arguments:
    // $first_reg is the sought semester
    // ----------------------------------------
    public function get_group_by_first_reg($first_reg) {

        // ----------
        // Iterate over the array and find the appropriate group.
        // ----------
        foreach ( $groups as $group ) {
            if ( $group->get_first_reg() == $first_reg ) {
                // Group found.
                return $group;
            }
        }

        // No group found.
        return null;

    }

    // ----------------------------------------
    // print_dump
    //
    // Print function for debugging / testing.
    // ----------------------------------------
    public function print_dump() {
        
        print "All Students for course: " . $this->course_code . ".\n";

        foreach ( $this->groups as $group ) {
            $group->print();
        }
    }
    
    // ----------------------------------------
    // get_all_students_xml_handler
    //
    // Returns xml_handler to all students file. This file only includes a list
    // of ALL students the course (forever).
    // ----------------------------------------
    private function get_all_students_xml_handler() {
    
        global $COURSE_INFO_PATH;
        $this->file_path = realpath($COURSE_INFO_PATH . '/' . $this->course_code . '/'
                         . '/all_students.xml');
        
        return xml_handler::get_xml_handler_for_file(realpath($this->file_path));
    }

    // ----------------------------------------
    // get_jsonversion_for_student
    //
    // Iterates over the student groups and attempts to find the
    // sought student. If found, returns the jsonversion for the
    // group. Returns "invalid" otherwise.
    //
    // Arguments:
    // $uid is a string containing the UID for the sought student.
    // ----------------------------------------
 
    // ----------------------------------------
    public function get_jsonversion_for_student($uid) {

        if ( isset($this->groups) && ! empty($this->groups) ) {
            foreach ( $this->groups as $group ) {
                if ( $group->contains_student($uid) ) {
                    return $group->get_jsonversion();
                }
            }
        }

        return "invalid";
    }
    
    // ----------------------------------------
    // End of All_Students class definition
    // ----------------------------------------
}

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