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/>.

/**

 * This file contains classes used to manage the navigation structures in Moodle

 * and was introduced as part of the changes occuring in Moodle 2.0

 *

 * @since     Moodle 2.0

 * @package   block_navigation

 * @copyright 2009 Sam Hemelryk

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

 */

/**

 * The global navigation tree block class

 *

 * Used to produce the global navigation block new to Moodle 2.0

 *

 * @package   block_navigation

 * @category  navigation

 * @copyright 2009 Sam Hemelryk

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

 */

class block_navigation extends block_base {

    /** @var int This allows for multiple navigation trees */

    public static $navcount;

    /** @var string The name of the block */

    public $blockname = null;

    /** @var bool A switch to indicate whether content has been generated or not. */

    protected $contentgenerated = false;

    /** @var bool|null variable for checking if the block is docked*/

    protected $docked = null;

    /** @var int Trim characters from the right */

    const TRIM_RIGHT = 1;

    /** @var int Trim characters from the left */

    const TRIM_LEFT = 2;

    /** @var int Trim characters from the center */

    const TRIM_CENTER = 3;

    /**

     * Set the initial properties for the block

     */

    function init() {

        $this->blockname = get_class($this);

        $this->title = get_string('pluginname', $this->blockname);

    }

    /**

     * All multiple instances of this block

     * @return bool Returns false

     */

    function instance_allow_multiple() {

        return false;

    }

    /**

     * Set the applicable formats for this block to all

     * @return array

     */

    function applicable_formats() {

        return array('all' => true);

    }

    /**

     * Allow the user to configure a block instance

     * @return bool Returns true

     */

    function instance_allow_config() {

        return true;

    }

    /**

     * The navigation block cannot be hidden by default as it is integral to

     * the navigation of Moodle.

     *

     * @return false

     */

    function instance_can_be_hidden() {

        return false;

    }

    /**

     * Find out if an instance can be docked.

     *

     * @return bool true or false depending on whether the instance can be docked or not.

     */

    function instance_can_be_docked() {

        return (parent::instance_can_be_docked() && (empty($this->config->enabledock) || $this->config->enabledock=='yes'));

    }

    /**

     * Gets Javascript that may be required for navigation

     */

    function get_required_javascript() {

        parent::get_required_javascript();

        $arguments = array(

            'instanceid' => $this->instance->id

        );

        $this->page->requires->string_for_js('viewallcourses', 'moodle');

        $this->page->requires->js_call_amd('block_navigation/navblock', 'init', $arguments);

    }

    /**

     * Gets the content for this block by grabbing it from $this->page

     *

     * @return object $this->content

     */

    function get_content() {

        global $CFG;

        // First check if we have already generated, don't waste cycles

        if ($this->contentgenerated === true) {

            return $this->content;

        }

        // JS for navigation moved to the standard theme, the code will probably have to depend on the actual page structure

        // $this->page->requires->js('/lib/javascript-navigation.js');

        // Navcount is used to allow us to have multiple trees although I dont' know why

        // you would want two trees the same

        block_navigation::$navcount++;

        // Check if this block has been docked

        if ($this->docked === null) {

            $this->docked = get_user_preferences('nav_in_tab_panel_globalnav'.block_navigation::$navcount, 0);

        }

        // Check if there is a param to change the docked state

        if ($this->docked && optional_param('undock', null, PARAM_INT)==$this->instance->id) {

            unset_user_preference('nav_in_tab_panel_globalnav'.block_navigation::$navcount);

            $url = $this->page->url;

            $url->remove_params(array('undock'));

            redirect($url);

        } else if (!$this->docked && optional_param('dock', null, PARAM_INT)==$this->instance->id) {

            set_user_preferences(array('nav_in_tab_panel_globalnav'.block_navigation::$navcount=>1));

            $url = $this->page->url;

            $url->remove_params(array('dock'));

            redirect($url);

        }

        $trimmode = self::TRIM_RIGHT;

        $trimlength = 50;

        if (!empty($this->config->trimmode)) {

            $trimmode = (int)$this->config->trimmode;

        }

        if (!empty($this->config->trimlength)) {

            $trimlength = (int)$this->config->trimlength;

        }

        // Get the navigation object or don't display the block if none provided.

        if (!$navigation = $this->get_navigation()) {

            return null;

        }

        $expansionlimit = null;

        if (!empty($this->config->expansionlimit)) {

            $expansionlimit = $this->config->expansionlimit;

            $navigation->set_expansion_limit($this->config->expansionlimit);

        }

        $this->trim($navigation, $trimmode, $trimlength, ceil($trimlength/2));

        // Get the expandable items so we can pass them to JS

        $expandable = array();

        $navigation->find_expandable($expandable);

        if ($expansionlimit) {

            foreach ($expandable as $key=>$node) {

                if ($node['type'] > $expansionlimit && !($expansionlimit == navigation_node::TYPE_COURSE && $node['type'] == $expansionlimit && $node['branchid'] == SITEID)) {

                    unset($expandable[$key]);

                }

            }

        }

        $limit = 20;

        if (!empty($CFG->navcourselimit)) {

            $limit = $CFG->navcourselimit;

        }

        $expansionlimit = 0;

        if (!empty($this->config->expansionlimit)) {

            $expansionlimit = $this->config->expansionlimit;

        }

        $options = array();

        $options['linkcategories'] = (!empty($this->config->linkcategories) && $this->config->linkcategories == 'yes');

        // Grab the items to display

        $renderer = $this->page->get_renderer($this->blockname);

        $this->content = new stdClass();

        $this->content->text = $renderer->navigation_tree($navigation, $expansionlimit, $options);

        // Set content generated to true so that we know it has been done

        $this->contentgenerated = true;

        return $this->content;

    }

    /**

     * Returns the navigation

     *

     * @return navigation_node The navigation object to display

     */

    protected function get_navigation() {

        // Initialise (only actually happens if it hasn't already been done yet)

        $this->page->navigation->initialise();

        return clone($this->page->navigation);

    }

    /**

     * Returns the attributes to set for this block

     *

     * This function returns an array of HTML attributes for this block including

     * the defaults.

     * {@link block_tree::html_attributes()} is used to get the default arguments

     * and then we check whether the user has enabled hover expansion and add the

     * appropriate hover class if it has.

     *

     * @return array An array of HTML attributes

     */

    public function html_attributes() {

        $attributes = parent::html_attributes();

        if (!empty($this->config->enablehoverexpansion) && $this->config->enablehoverexpansion == 'yes') {

            $attributes['class'] .= ' block_js_expansion';

        }

        return $attributes;

    }

    /**

     * Trims the text and shorttext properties of this node and optionally

     * all of its children.

     *

     * @param navigation_node $node

     * @param int $mode One of navigation_node::TRIM_*

     * @param int $long The length to trim text to

     * @param int $short The length to trim shorttext to

     * @param bool $recurse Recurse all children

     */

    public function trim(navigation_node $node, $mode=1, $long=50, $short=25, $recurse=true) {

        switch ($mode) {

            case self::TRIM_RIGHT :

                if (core_text::strlen($node->text)>($long+3)) {

                    // Truncate the text to $long characters

                    $node->text = $this->trim_right($node->text, $long);

                }

                if (is_string($node->shorttext) && core_text::strlen($node->shorttext)>($short+3)) {

                    // Truncate the shorttext

                    $node->shorttext = $this->trim_right($node->shorttext, $short);

                }

                break;

            case self::TRIM_LEFT :

                if (core_text::strlen($node->text)>($long+3)) {

                    // Truncate the text to $long characters

                    $node->text = $this->trim_left($node->text, $long);

                }

                if (is_string($node->shorttext) && core_text::strlen($node->shorttext)>($short+3)) {

                    // Truncate the shorttext

                    $node->shorttext = $this->trim_left($node->shorttext, $short);

                }

                break;

            case self::TRIM_CENTER :

                if (core_text::strlen($node->text)>($long+3)) {

                    // Truncate the text to $long characters

                    $node->text = $this->trim_center($node->text, $long);

                }

                if (is_string($node->shorttext) && core_text::strlen($node->shorttext)>($short+3)) {

                    // Truncate the shorttext

                    $node->shorttext = $this->trim_center($node->shorttext, $short);

                }

                break;

        }

        if ($recurse && $node->children->count()) {

            foreach ($node->children as &$child) {

                $this->trim($child, $mode, $long, $short, true);

            }

        }

    }

    /**

     * Truncate a string from the left

     * @param string $string The string to truncate

     * @param int $length The length to truncate to

     * @return string The truncated string

     */

    protected function trim_left($string, $length) {

        return '...'.core_text::substr($string, core_text::strlen($string)-$length, $length);

    }

    /**

     * Truncate a string from the right

     * @param string $string The string to truncate

     * @param int $length The length to truncate to

     * @return string The truncated string

     */

    protected function trim_right($string, $length) {

        return core_text::substr($string, 0, $length).'...';

    }

    /**

     * Truncate a string in the center

     * @param string $string The string to truncate

     * @param int $length The length to truncate to

     * @return string The truncated string

     */

    protected function trim_center($string, $length) {

        $trimlength = ceil($length/2);

        $start = core_text::substr($string, 0, $trimlength);

        $end = core_text::substr($string, core_text::strlen($string)-$trimlength);

        $string = $start.'...'.$end;

        return $string;

    }

    /**

     * Returns the role that best describes the navigation block... 'navigation'

     *

     * @return string 'navigation'

     */

    public function get_aria_role() {

        return 'navigation';

    }

    /**

     * Return the plugin config settings for external functions.

     *

     * @return stdClass the configs for both the block instance and plugin

     * @since Moodle 3.8

     */

    public function get_config_for_external() {

        // Return all settings for all users since it is safe (no private keys, etc..).

        $configs = !empty($this->config) ? $this->config : new stdClass();

        return (object) [

            'instance' => $configs,

            'plugin' => new stdClass(),

        ];

    }

}