<?php
// ----------------------------------------------------------------------------
// result_part.php
// Contains the Result_Part class definition.
// ----------------------------------------------------------------------------

require_once '/projects/lupp/2-1-devel//www/common/xml_handler.php';
require_once 'result_sub_part.php';
require_once '/projects/lupp/2-1-devel//bin_external/lib/common.php';
require_once '/projects/lupp/2-1-devel//www/classes/course_description/course_description.php';

// ----------------------------------------
// The Result_Part class (ex. LAB1, DAT1...) contains all the
// result_sub_parts and meta data for this particular 
// ----------------------------------------
class Result_Part {

    // ----------------------------------------
    // Instance variables
    // ----------------------------------------
    // Attributes
    private $name;
    private $grade;
    private $reported;
    private $report_name;
    
    // Sub tags
    private $sub_parts;

    // Data needed for file storage
    private $is_new;
    private $changes;
    private $is_modified;
    
    // ----------------------------------------
    // 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() {

        $this->is_modified = false;
        $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->changes = array();
        $this->sub_parts = array();
        $this->name = $xml_data->getAttribute('name');
        $this->grade = $xml_data->getAttribute('grade');
        $this->reported = $xml_data->getAttribute('reported');

        if ( $xml_data->hasChildNodes() ) {
            $sub_part_data = $xml_data->getElementsByTagName('lab');
            foreach ( $sub_part_data as $sub_part ) {
                $this->sub_parts[] = new Result_Sub_Part($sub_part);
            }
        }
    }
    
    // ----------------------------------------
    // Constructor
    //
    // Initiates instance variables and creates classes based on
    // previously extracted data. Not using default parameters to
    // distinguish the call signature from the other constructor.
    //
    // Arguments:
    //   $name is the name of the result part
    //   $grade is the grade to be reported for the whole result part
    //   null if it's not ready for a full grade
    //   $reported_date is the date the result part was reported, null
    //   if not reported.
    // ----------------------------------------
    public function __construct3($name,
                                 $grade,
                                 $reported_date) {

        $this->changes = array();
        $this->sub_parts = array();
        $this->is_new = true;
        $this->name = $name;
        $this->grade = $grade;
        $this->reported = $reported_date;
     }
    
    // ----------------------------------------
    // Constructor
    //
    // Initiates instance variables and creates classes based on
    // previously extracted data. Not using default parameters to
    // distinguish the call signature from the other constructor.
    //
    // Arguments:
    //   $name is the name of the result part
    //   $grade is the grade to be reported for the whole result part
    //   null if it's not ready for a full grade
    //   $reported_date is the date the result part was reported, null
    //   if not reported.
    //   $report_name is a default null parameter, if this course part
    //   has a different report name (Ex: DAT1 might be TEN1 in some
    //   courses), this is the parameter to control this
    // ----------------------------------------
    public function __construct4($name,
                                 $grade,
                                 $reported_date,
                                 $report_name) {

        $this->changes = array();
        $this->sub_parts = array();
        $this->is_new = true;
        $this->name = $name;
        $this->grade = $grade;
        $this->reported = $reported_date;
        $this->report_name = $report_name;
    }
    
    // ----------------------------------------
    // get_name
    //
    // Returns the name of the result part.
    // ----------------------------------------
    public function get_name() {
        
        return $this->name;
    }
    
    // ----------------------------------------
    // get_grade
    //
    // Returns the grade set for the result part.
    // ----------------------------------------
    public function get_grade() {
        
        return $this->grade;
    }

    // ----------------------------------------
    // get_grade_except_u
    //
    // Returns the grade set for the result part unless that grade is
    // U, in which case we return "" (empty string). 
    // ----------------------------------------
    public function get_grade_except_u() {

        if ( ! isset($this->grade) ||
             strcasecmp($this->grade, "U") == 0 ) {

            return "";
        }

        return $this->grade;
    }
    
    // ----------------------------------------
    // set_grade
    //
    // Set a new grade for this result part.
    //
    // Arguments:
    //   $new_grade - string containing the new grade (String)
    // ----------------------------------------
    public function set_grade($new_grade) {

        $this->grade = $new_grade;
        $this->is_modified = true;
    }

    // ----------------------------------------
    // get_reported
    //
    // Returns the reported date for this result part.
    // ----------------------------------------
    public function get_reported() {

        return $this->reported;
    }
    
    // ----------------------------------------
    // set_reported
    //
    // Set a new reported date for this result part.
    //
    // Arguments:
    //   $reported_date - string containing the date on the format:
    //   "YYYY-MM-DD" (String)
    // ----------------------------------------
    public function set_reported($reported_date) {

        $this->reported = $reported_date;
        $this->is_modified = true;
    }
    
    // ----------------------------------------
    // get_report_name
    //
    // Returns the report name for this result part.
    // ----------------------------------------
    public function get_report_name() {

        return $this->report_name;
    }

    // ----------------------------------------
    // set_report_name
    //
    // Set a new report namefor this result part.
    //
    // Arguments:
    //   $report_name - string containing the new report name, ex:
    //   "TEN1"
    // ----------------------------------------
    public function set_report_name($report_name) {

        $this->report_name = $report_name;
        $this->is_modified = true;
    }

    // ----------------------------------------
    // get_sub_parts
    //
    // Returns an array with all the sub parts to this.
    // ----------------------------------------
    public function get_sub_parts() {

        return $this->sub_parts;
    }

    // ----------------------------------------
    // has_changes
    //
    // Returns true if there are stored changes, false otherwise.
    // ----------------------------------------
    public function has_changes() {

        return ( ( isset($this->changes) && ( ! empty($this->changes) ) ) || $this->is_modified ) ;
    }

    // ----------------------------------------
    // is_new
    //
    // Returns true if this is a new object (reported, not loaded from
    // file), false otherwise.
    // ----------------------------------------
    public function is_new() {

        return $this->is_new;
    }
    
    // ----------------------------------------
    // get_sub_part_by_id
    //
    // Returns a sub part object matching the $id, null if no such sub
    // part exists.
    //
    // Arguments:
    //   $id - string containing the desired sub part id. Ex:
    //   Ada.O1. (String)
    // ----------------------------------------
    public function get_sub_part_by_id($id) {

        // ----------
        // Ensure that we have sub parts, and if we do: iterate over
        // them until we find the one corresponding with $id
        // ----------
        if ( isset($this->sub_parts) && ! empty($this->sub_parts) ) {
            foreach ( $this->sub_parts as $sub ) {
                if ( strcasecmp($id, $sub->get_id()) == 0 ) {
                    // Match found
                    return $sub;
                }
            }
        }

        // No match was found
        return null;
    }

    // ----------------------------------------
    // insert_new_sub_part_result
    //
    // Insert a new, or modify the state of an existing, result sub
    // part for this student based on extracted data. Will not
    // overwrite "passed" grade on the normal state, regardless of
    // what is being reported. Only one of $state or $autostate should
    // be set. The other one should be set to null. If $state is set,
    // $autostate will be ignored.
    //
    // Arguments:
    //   $id is the new result sub part id
    //   $state is the state to set for the sub part
    //   $autostate is the autostate to set for the new sub part.
    // 
    // Returns the new result sub part. If a result sub part by this
    // name already exists, that part will be modified according to
    // the parameters and returned.
    // ----------------------------------------
    public function insert_new_sub_part_result($id,
                                               $state,
                                               $autostate) {

        // We have previously confirmed (to get this far) that
        // everything is in order with this course part. Regardless if
        // this part is reported already, we have to be able to work
        // with sub parts (e.g. reported with grade 3, trying to
        // increase to 4 or 5).
        
        $sub_part = $this->get_sub_part_by_id($id);
        
        // ----------
        // Check if the sub part exists previously, if not create it.
        // ----------
        if ( ! isset($sub_part) ) {
            // We had no previous sub part by this name, so we create
            // it.
            $sub_part = new Result_Sub_Part($id, $state, $autostate);
            $this->sub_parts[] = $sub_part;
            $this->changes[] = $sub_part;
            return $sub_part;
        }

        // ----------
        // The part already exists.  Check whether we have an
        // autostate report or a normal state and report the
        // results. If both have been sent we will give precedence
        // to $state.
        // ----------
	if ( isset($state) ) {
            $sub_part->set_state($state);
            $sub_part->set_auto_state($state);
        }
        else {
            $sub_part->set_state($autostate);
            $sub_part->set_auto_state($autostate);
        }
                
        // We have mofications to the sub part, or created a new
        // one, so we store the part as changed to make saving to
        // file quicker.
        $this->changes[] = $sub_part;
                
        return $sub_part;
    }

    // ----------------------------------------
    // insert_new_sub_part_result_unsafe
    //
    // Insert a new, or modify the state of an existing, result sub
    // part for this student based on extracted data. WILL ALLOW
    // OVERWRITING "passed" grade on the normal state, regardless of
    // what is being reported. Only one of $state or $autostate should
    // be set. The other one should be set to null. If $state is set,
    // $autostate will be ignored.
    //
    // Arguments:
    //   $id is the new result sub part id
    //   $state is the state to set for the sub part
    //   $autostate is the autostate to set for the new sub part.
    // 
    // Returns the new result sub part. If a result sub part by this
    // name already exists, that part will be modified according to
    // the parameters and returned.
    // ----------------------------------------
    public function insert_new_sub_part_result_unsafe($id,
                                                      $state,
                                                      $autostate) {

        // We have previously confirmed (to get this far) that
        // everything is in order with this course part. Regardless if
        // this part is reported already, we have to be able to work
        // with sub parts (e.g. reported with grade 3, trying to
        // increase to 4 or 5).
        
        $sub_part = $this->get_sub_part_by_id($id);
        
        // ----------
        // Check if the sub part exists previously, if not create it.
        // ----------
        if ( ! isset($sub_part) ) {
            // We had no previous sub part by this name, so we create
            // it.
            $sub_part = new Result_Sub_Part($id, $state, $autostate);
            $this->sub_parts[] = $sub_part;
            $this->changes[] = $sub_part;
            return $sub_part;
        }

        // ----------
        // The part already exists.  Check whether we have an
        // autostate report or a normal state and report the
        // results. If both have been sent we will give precedence
        // to $state.
        // ----------
	if ( isset($state) ) {
            // Here we call set_state_unsafe to report the state
            // regardless of whether the student previously had a
            // passing mark or not.
            $sub_part->set_state_unsafe($state);
            $sub_part->set_auto_state($state);
        }
        else {
            // Even the unchecked method should not downgrade passed
            // state to an autostate so we do not call the unsafe
            // method here. This should not be done (ever), but we
	    // make this for safety (might be wrong if "autocorrect"
	    // makes calls to this one in the future).
            $sub_part->set_state($autostate);
            $sub_part->set_auto_state($autostate);
        }
                
        // We have mofications to the sub part, or created a new
        // one, so we store the part as changed to make saving to
        // file quicker.
        $this->changes[] = $sub_part;
                
        return $sub_part;
    }

    
    // ----------------------------------------
    // print_dump
    //
    // Print function for debugging / testing.
    // ----------------------------------------
    public function print_dump() {
        
        print "\t\tCoures part name: " . $this->name
                                       . ", grade: " . $this->grade
                                       . ", reported: " . $this->reported
                                       . "\n";
        
        foreach ( $this->sub_parts as $sub ) {
            $sub->print_dump();
        }
    }

    // ----------------------------------------
    // to_json
    //
    // Creates a json string representation of the student result.
    //
    // Arguments:
    //   $indentation is the count of tabs to indent the json data,
    //   default 0. Used for when the json data should be nested
    //   inside another json object.
    //
    // Returns a string containing the json representation of the
    // student result
    // ----------------------------------------
    public function to_json($indentation = 0) {
    
        // Extract and "jsonify" attributes that are always present.
        $res = str_repeat("\t", $indentation) . "{\n" 
             . str_repeat("\t", $indentation+1) . "\"part name\": \"" . $this->name . "\"";

        // ----------
        // Check if the attributes the can be empty contain data, if
        // so "jsonify" and add them.
        // ----------
        if ( isset($this->grade) ) {
            $res .= ",\n" . str_repeat("\t", $indentation) . "\t\"grade\": \"" . $this->grade . "\"";
        }

        if ( isset($this->reported) ) {
            $res .= ",\n" . str_repeat("\t", $indentation) . "\t\"reported\": \"" . $this->reported . "\"";
        }

        // ----------
        // Check if the students have any sub parts to this result
        // part, if so append json-representations of those sub parts.
        // ----------
        if ( isset($this->sub_parts) && ( ! empty($this->sub_parts) ) ) {
	    
	    // We have results for this student.
            $res .= ",\n"; 
            $count = count($this->sub_parts);
            $res .= str_repeat("\t", $indentation+1) . "\"labs\": [\n";
            for ($i = 0; $i < $count; $i++) {
                $sub_part = $this->sub_parts[$i];
                $res .= $sub_part->to_json($indentation + 2);

                if ( $i < $count - 1 ) {
                    // We're not on the last element
                    $res .= ",\n";
                }
                else {
                    // Last element
                    $res .= "\n";
                }
            }
            $res .= str_repeat("\t", $indentation + 1) . "]\n";
        }
	else {
	    $res .= "\n";
	}
        $res .= str_repeat("\t", $indentation) . "}";
        return $res;
    }
    
    // ----------------------------------------
    // to_json_full
    //
    // Creates a json string representation of the student result.
    //
    // Arguments:
    //   $course_descript is the course description object used to
    //   find all mandatory course sub parts for old students.
    //   $indentation is the count of tabs to indent the json data,
    //   default 0. Used for when the json data should be nested
    //   inside another json object.
    //
    // Returns a string containing the json representation of the
    // student result
    // ----------------------------------------
    public function to_json_full($course_description,
                                 $indentation = 0) {

	$stored = false;
        // Extract and "jsonify" attributes that are always present.
        $res = str_repeat("\t", $indentation) . "{\n" 
             . str_repeat("\t", $indentation+1) . "\"part name\": \"" . $this->name . "\"";

        // ----------
        // Check if the attributes the can be empty contain data, if
        // so "jsonify" and add them.
        // ----------
        if ( isset($this->grade) ) {
            $res .= ",\n" . str_repeat("\t", $indentation) . "\t\"grade\": \"" . $this->grade . "\"";
        }

        if ( isset($this->reported) ) {
            $res .= ",\n" . str_repeat("\t", $indentation) . "\t\"reported\": \"" . $this->reported . "\"";
        }

        // ----------
        // Check if the students have any sub parts to this result
        // part, if so append json-representations of those sub parts.
        // ----------
        if ( isset($this->reported) && ( ! empty($this->reported) ) &&
             ( strcasecmp($this->grade, "U") != 0 ) ) {
	    
            // Student has already been reported with a grade for this
            // part. We want to report all mandatory sub parts as
            // passing, and all non mandatory parts with whatever
            // state they have.
            $cd_part = $course_description->find_part_by_name($this->name);
	    if ( $cd_part == null ) {
		// We have an old course part that no longer exists in
		// course description.
		return "";
	    }
            $count = 0;
	    $total_subs = count($cd_part->get_sub_parts());
	    $mandatory_parts = $cd_part->count_mandatory_sub_parts();

            if ( $total_subs > 0 && $cd_part->has_mandatory_sub_parts() ) {
		$res .= ",\n"; 
		$res .= str_repeat("\t", $indentation+1) . "\"labs\": [\n";
		$stored = true;
	    }

	    foreach ( $cd_part->get_sub_parts() as $sub ) {
                if ( $sub->is_mandatory() ) {
		 
		    $count++;
                    $res .= str_repeat("\t", $indentation+2) . "{\n" 
                         . str_repeat("\t", $indentation+3) . "\"id\": \"" . $sub->get_name() . "\",\n"
                         . str_repeat("\t", $indentation+3) . "\"state\": \"passed\"";
                    $res .= "\n" . str_repeat("\t", $indentation+2) . "}";

                    if ( $count < $mandatory_parts ) {
                        $res .= ",\n";
                    }
                }
            }
        }

	$sub_count = $this->count_missing_sub_parts($res);
	    
        if ( isset($this->sub_parts) && ( ! empty($this->sub_parts) ) ) {
	    if ( $stored  && $sub_count > 0 ) {
		$res .= ",\n"; 
	    }
	    elseif ( $stored ) {
		$res .= "\n";
	    }
            elseif ( $sub_count > 0 ) {
		$res .= ",\n";
		$res .= str_repeat("\t", $indentation+1) . "\"labs\": [\n";
            }

	    $finished = 0;
	    foreach ( $this->sub_parts as $sub_part ) {
                if ( ! string_contains($res, '"' . $sub_part->get_id() . '"') ) { 
                    $finished++;
		    $res .= $sub_part->to_json($indentation + 2);
		    
		    if ( $finished < $sub_count ) {
			// We're not on the last element
                        $res .= ",\n";
                    }
                    else {
                        // Last element
                        $res .= "\n";
                    }
                } 
            }
	    if ( $stored || count($this->sub_parts) > 0 ) {
		$res .= str_repeat("\t", $indentation + 1) . "]\n";
	    }
        }
        elseif ( $stored ) {
            $res .= str_repeat("\t", $indentation + 1) . "]\n";
        }
        else {
            $res .= "\n";
        }
        $res .= str_repeat("\t", $indentation) . "}";
        return $res;
    }
    
    private function count_missing_sub_parts($str) {
	$count = 0;
	foreach ( $this->sub_parts as $sub_part ) {
	    if ( ! string_contains($str, '"' . $sub_part->get_id() . '"') ) {
		$count++;
	    }
	}
	return $count;
    }

    // ----------------------------------------
    // save_results_to_file
    //
    // Stores the results for this student result part on the given
    // file. We know the student exists in active students for this
    // course
    //
    // Arguments:
    //   $xml_path is the DOMDXpath for the xml_handler document.
    //   $xml_document is the DOMDocument in which to store the changes.
    //   $deadlines is an array of deadlines fetched from course info.
    //   $student_elem the student xml element to append parts to.
    //   $uid is the uid of the student, needed to extract xml data.
    //
    // Returns true if successfully saved, false otherwise, to handle
    // errors outside.
    // ----------------------------------------
    public function save_results_to_file($xml_path,
                                         $xml_document,
                                         $deadlines,
                                         $student_elem,
                                         $uid) {

        $clean_save = true;
        // Extract the student part from the xml document.
        $xml_element = $xml_path->query("//student[@uid='{$uid}']/part[@name='{$this->name}']");

        if ( ! $xml_element->length || ( ! isset($xml_element) ) ) {
            // The course part did not previously exist in the results
            // document for this student, so we create it and append
            // the attributes.
            $part_elem = $xml_document->createElement('part');
           
            $part_elem->setAttribute('name', $this->name);
   
            $part_elem = $student_elem->appendChild($part_elem);
        }
        else if ( $xml_element->length > 1 ) {
            print "ERROR: Student |" . $uid . "| has multiple entries of |"
                                     . $this->name . "| in the data files.";
        }
        else {
            // Only one entry of this student / course part
            // combination existed previously.
            $part_elem = $xml_element->item(0);
        }
        
        // ----------
        // Check the optional attributes and store them if they
        // have a value.
        // ----------
        if ( isset($this->grade) and ! empty($this->grade) ) {
            $part_elem->setAttribute('grade', $this->grade);
        }
        
        if ( isset($this->reported) and ! empty($this->reported) ) {
            $part_elem->setAttribute('reported', $this->reported);
        }
        
        // ----------
        // Check if we have any changes, and if so iterate over them
        // and save those changes.
        // ----------
        if ( isset($this->changes) and ! empty($this->changes) ) { 
            foreach ( $this->changes as $sub ) {
                if ( $sub->has_changes() or $sub->is_new() ) {
                    if ( ! $sub->save_results_to_file($xml_path, $xml_document, $deadlines, $part_elem, $uid, $this->name) ) {
                        $clean_save = false;
                    }
                }
            }
        }
        $this->is_modified = false;
        return $clean_save;
    }
    
    // ----------------------------------------
    // End of Result_Part class definition
    // ----------------------------------------
}

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