Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * Class for loading/storing competency frameworks from the DB.

 *

 * @package    core_competency

 * @copyright  2015 Damyon Wiese

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

namespace core_competency;

defined('MOODLE_INTERNAL') || die();

use coding_exception;

use context;

use lang_string;

use stdClass;

require_once($CFG->libdir . '/grade/grade_scale.php');

/**

 * Class for loading/storing competency frameworks from the DB.

 *

 * @copyright  2015 Damyon Wiese

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class competency_framework extends persistent {

    const TABLE = 'competency_framework';

    /** Taxonomy constant. */

    const TAXONOMY_BEHAVIOUR = 'behaviour';

    /** Taxonomy constant. */

    const TAXONOMY_COMPETENCY = 'competency';

    /** Taxonomy constant. */

    const TAXONOMY_CONCEPT = 'concept';

    /** Taxonomy constant. */

    const TAXONOMY_DOMAIN = 'domain';

    /** Taxonomy constant. */

    const TAXONOMY_INDICATOR = 'indicator';

    /** Taxonomy constant. */

    const TAXONOMY_LEVEL = 'level';

    /** Taxonomy constant. */

    const TAXONOMY_OUTCOME = 'outcome';

    /** Taxonomy constant. */

    const TAXONOMY_PRACTICE = 'practice';

    /** Taxonomy constant. */

    const TAXONOMY_PROFICIENCY = 'proficiency';

    /** Taxonomy constant. */

    const TAXONOMY_SKILL = 'skill';

    /** Taxonomy constant. */

    const TAXONOMY_VALUE = 'value';

    /** @var static The object before it was updated. */

    protected $beforeupdate;

    /**

     * Get the context.

     *

     * @return \context The context

     */

    public function get_context() {

        return context::instance_by_id($this->get('contextid'));

    }

    /**

     * Return the definition of the properties of this model.

     *

     * @return array

     */

    protected static function define_properties() {

        return array(

            'shortname' => array(

                'type' => PARAM_TEXT

            ),

            'idnumber' => array(

                'type' => PARAM_RAW

            ),

            'description' => array(

                'type' => PARAM_CLEANHTML,

                'default' => ''

            ),

            'descriptionformat' => array(

                'choices' => array(FORMAT_HTML, FORMAT_MOODLE, FORMAT_PLAIN, FORMAT_MARKDOWN),

                'type' => PARAM_INT,

                'default' => FORMAT_HTML

            ),

            'visible' => array(

                'type' => PARAM_BOOL,

                'default' => 1

            ),

            'scaleid' => array(

                'type' => PARAM_INT

            ),

            'scaleconfiguration' => array(

                'type' => PARAM_RAW

            ),

            'contextid' => array(

                'type' => PARAM_INT

            ),

            'taxonomies' => array(

                'type' => PARAM_RAW,

                'default' => ''

            )

        );

    }

    /**

     * Hook to execute before validate.

     *

     * @return void

     */

    protected function before_validate() {

        $this->beforeupdate = null;

        // During update.

        if ($this->get('id')) {

            $this->beforeupdate = new competency_framework($this->get('id'));

        }

    }

    /**

     * Return the current depth of a competency framework.

     *

     * @see competency::get_framework_depth()

     * @return int

     */

    public function get_depth() {

        return competency::get_framework_depth($this->get('id'));

    }

    /**

     * Return the scale.

     *

     * @return \grade_scale

     */

    public function get_scale() {

        $scale = \grade_scale::fetch(array('id' => $this->get('scaleid')));

        $scale->load_items();

        return $scale;

    }

    /**

     * Get the constant name for a level.

     *

     * @param  int $level The level of the term.

     * @return string

     */

    public function get_taxonomy($level) {

        $taxonomies = $this->get_taxonomies();

        if (empty($taxonomies[$level])) {

            // If for some reason we cannot find the level, we fallback onto competency.

            $constant = self::TAXONOMY_COMPETENCY;

        } else {

            $constant = $taxonomies[$level];

        }

        return $constant;

    }

    /**

     * Return the taxonomy constants indexed by level.

     *

     * @return array Contains the list of taxonomy constants indexed by level.

     */

    protected function get_taxonomies() {

        $taxonomies = explode(',', $this->raw_get('taxonomies'));

        // Indexing first level at 1.

        array_unshift($taxonomies, null);

        unset($taxonomies[0]);

        // Ensure that we do not return empty levels.

        foreach ($taxonomies as $i => $taxonomy) {

            if (empty($taxonomy)) {

                $taxonomies[$i] = self::TAXONOMY_COMPETENCY;

            }

        }

        return $taxonomies;

    }

    /**

     * Returns true when some competencies of the framework have user competencies.

     *

     * This is useful to determine if the framework, or part of it, should be locked down.

     *

     * @return boolean

     */

    public function has_user_competencies() {

        return user_competency::has_records_for_framework($this->get('id')) ||

            user_competency_plan::has_records_for_framework($this->get('id'));

    }

    /**

     * Convenience method to set taxonomies from an array or string.

     *

     * @param string|array $taxonomies A string, or an array where the values are the term constants.

     */

    protected function set_taxonomies($taxonomies) {

        if (is_array($taxonomies)) {

            $taxonomies = implode(',', $taxonomies);

        }

        $this->raw_set('taxonomies', $taxonomies);

    }

    /**

     * Validate the context ID.

     *

     * @param  int $value The context ID.

     * @return bool|lang_string

     */

    protected function validate_contextid($value) {

        global $DB;

        $context = context::instance_by_id($value, IGNORE_MISSING);

        if (!$context) {

            return new lang_string('invalidcontext', 'error');

        } else if ($context->contextlevel != CONTEXT_SYSTEM && $context->contextlevel != CONTEXT_COURSECAT) {

            return new lang_string('invalidcontext', 'error');

        }

        // During update.

        if ($this->get('id')) {

            // The context must never change.

            $oldcontextid = $DB->get_field(self::TABLE, 'contextid', array('id' => $this->get('id')), MUST_EXIST);

            if ($this->get('contextid') != $oldcontextid) {

                return new lang_string('invalidcontext', 'error');

            }

        }

        return true;

    }

    /**

     * Validate the id number.

     *

     * @param  string $value The id number.

     * @return bool|lang_string

     */

    protected function validate_idnumber($value) {

        global $DB;

        $params = array(

            'id' => $this->get('id'),

            'idnumber' => $value,

        );

        if ($DB->record_exists_select(self::TABLE, 'idnumber = :idnumber AND id <> :id', $params)) {

            return new lang_string('idnumbertaken', 'error');

        }

        return true;

    }

    /**

     * Validate the scale ID.

     *

     * @param  string $value The scale ID.

     * @return bool|lang_string

     */

    protected function validate_scaleid($value) {

        global $DB;

        // Always validate that the scale exists.

        if (!$DB->record_exists_select('scale', 'id = :id', array('id' => $value))) {

            return new lang_string('invalidscaleid', 'error');

        }

        // During update.

        if ($this->get('id')) {

            // Validate that we can only change the scale when it is not used yet.

            if ($this->beforeupdate->get('scaleid') != $value) {

                if ($this->beforeupdate->has_user_competencies()) {

                    return new lang_string('errorscalealreadyused', 'core_competency');

                }

            }

        }

        return true;

    }

    /**

     * Validate the scale configuration.

     *

     * @param  string $value The scale configuration.

     * @return bool|lang_string

     */

    protected function validate_scaleconfiguration($value) {

        $scaledefaultselected = false;

        $proficientselected = false;

        $scaleconfigurations = json_decode($value);

        if (is_array($scaleconfigurations)) {

            // The first element of the array contains the scale ID.

            $scaleinfo = array_shift($scaleconfigurations);

            if (empty($scaleinfo) || !isset($scaleinfo->scaleid) || $scaleinfo->scaleid != $this->get('scaleid')) {

                // This should never happen.

                return new lang_string('errorscaleconfiguration', 'core_competency');

            }

            // Walk through the array to find proficient and default values.

            foreach ($scaleconfigurations as $scaleconfiguration) {

                if (isset($scaleconfiguration->scaledefault) && $scaleconfiguration->scaledefault) {

                    $scaledefaultselected = true;

                }

                if (isset($scaleconfiguration->proficient) && $scaleconfiguration->proficient) {

                    $proficientselected = true;

                }

            }

        }

        if (!$scaledefaultselected || !$proficientselected) {

            return new lang_string('errorscaleconfiguration', 'core_competency');

        }

        return true;

    }

    /**

     * Validate taxonomies.

     *

     * @param  mixed $value The taxonomies.

     * @return true|lang_string

     */

    protected function validate_taxonomies($value) {

        $terms = explode(',', $value);

        foreach ($terms as $term) {

            if (!empty($term) && !array_key_exists($term, self::get_taxonomies_list())) {

                return new lang_string('invalidtaxonomy', 'core_competency', $term);

            }

        }

        return true;

    }

    /**

     * Extract the default grade from a scale configuration.

     *

     * Returns an array where the first element is the grade, and the second

     * is a boolean representing whether or not this grade is considered 'proficient'.

     *

     * @param  string $config JSON encoded config.

     * @return array(int grade, int proficient)

     */

    public static function get_default_grade_from_scale_configuration($config) {

        $config = json_decode($config);

        if (!is_array($config)) {

            throw new coding_exception('Unexpected scale configuration.');

        }

        // Remove the scale ID from the config.

        array_shift($config);

        foreach ($config as $part) {

            if ($part->scaledefault) {

                return array((int) $part->id, (int) $part->proficient);

            }

        }

        throw new coding_exception('Invalid scale configuration, default not found.');

    }

    /**

     * Extract the proficiency of a grade from a scale configuration.

     *

     * @param  string $config JSON encoded config.

     * @param  int $grade The grade.

     * @return int Representing a boolean

     */

    public static function get_proficiency_of_grade_from_scale_configuration($config, $grade) {

        $config = json_decode($config);

        if (!is_array($config)) {

            throw new coding_exception('Unexpected scale configuration.');

        }

        // Remove the scale ID from the config.

        array_shift($config);

        foreach ($config as $part) {

            if ($part->id == $grade) {

                return (int) $part->proficient;

            }

        }

        return 0;

    }

    /**

     * Get the string of a taxonomy from a constant

     *

     * @param  string $constant The taxonomy constant.

     * @return lang_string

     */

    public static function get_taxonomy_from_constant($constant) {

        return self::get_taxonomies_list()[$constant];

    }

    /**

     * Get the list of all taxonomies.

     *

     * @return array Where the key is the taxonomy constant, and the value its translation.

     */

    public static function get_taxonomies_list() {

        static $list = null;

        // At some point we'll have to switch to not using static cache, mainly for Unit Tests in case we

        // decide to allow more taxonomies to be added dynamically from a CFG variable for instance.

        if ($list === null) {

            $list = array(

                self::TAXONOMY_BEHAVIOUR => new lang_string('taxonomy_' . self::TAXONOMY_BEHAVIOUR, 'core_competency'),

                self::TAXONOMY_COMPETENCY => new lang_string('taxonomy_' . self::TAXONOMY_COMPETENCY, 'core_competency'),

                self::TAXONOMY_CONCEPT => new lang_string('taxonomy_' . self::TAXONOMY_CONCEPT, 'core_competency'),

                self::TAXONOMY_DOMAIN => new lang_string('taxonomy_' . self::TAXONOMY_DOMAIN, 'core_competency'),

                self::TAXONOMY_INDICATOR => new lang_string('taxonomy_' . self::TAXONOMY_INDICATOR, 'core_competency'),

                self::TAXONOMY_LEVEL => new lang_string('taxonomy_' . self::TAXONOMY_LEVEL, 'core_competency'),

                self::TAXONOMY_OUTCOME => new lang_string('taxonomy_' . self::TAXONOMY_OUTCOME, 'core_competency'),

                self::TAXONOMY_PRACTICE => new lang_string('taxonomy_' . self::TAXONOMY_PRACTICE, 'core_competency'),

                self::TAXONOMY_PROFICIENCY => new lang_string('taxonomy_' . self::TAXONOMY_PROFICIENCY, 'core_competency'),

                self::TAXONOMY_SKILL => new lang_string('taxonomy_' . self::TAXONOMY_SKILL, 'core_competency'),

                self::TAXONOMY_VALUE => new lang_string('taxonomy_' . self::TAXONOMY_VALUE, 'core_competency'),

            );

        }

        return $list;

    }

    /**

     * Get a uniq idnumber.

     *

     * @param string $idnumber the framework idnumber

     * @return string

     */

    public static function get_unused_idnumber($idnumber) {

        global $DB;

        $currentidnumber = $idnumber;

        $counter = 0;

        // Iteratere while the idnumber exists.

        while ($DB->record_exists_select(static::TABLE, 'idnumber = ?', array($currentidnumber))) {

            $suffixidnumber = '_' . ++$counter;

            $currentidnumber = substr($idnumber, 0, 100 - strlen($suffixidnumber)).$suffixidnumber;

        }

        // Return the uniq idnumber.

        return $currentidnumber;

    }

    /**

     * Whether or not the current user can manage the framework.

     *

     * @return bool

     */

    public function can_manage() {

        return self::can_manage_context($this->get_context());

    }

    /**

     * Whether or not the current user can manage the framework.

     *

     * @param  context $context

     * @return bool

     */

    public static function can_manage_context($context) {

        return has_capability('moodle/competency:competencymanage', $context);

    }

    /**

     * Whether or not the current user can read the framework.

     *

     * @return bool

     */

    public function can_read() {

        return self::can_read_context($this->get_context());

    }

    /**

     * Whether or not the current user can read the framework.

     *

     * @param  context $context

     * @return bool

     */

    public static function can_read_context($context) {

        return has_capability('moodle/competency:competencyview', $context) || self::can_manage_context($context);

    }

}