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/>.

namespace tool_brickfield\local\tool;

use tool_brickfield\manager;

/**

 * Brickfield accessibility tool base class.

 *

 * All common properties and methods for all tool types.

 *

 * @package     tool_brickfield

 * @copyright  2020 onward: Brickfield Education Labs, www.brickfield.ie

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

 */

abstract class tool {

    /** @var string[] All of the tools provided. */

    const TOOLNAMES = ['errors', 'activityresults', 'checktyperesults', 'printable', 'advanced'];

    /** @var string base64 bitmap image type */

    const BASE64_BMP = 'data:image/bmp;base64';

    /** @var string base64 gif image type */

    const BASE64_GIF = 'data:image/gif;base64';

    /** @var string base64 jpg image type */

    const BASE64_JPG = 'data:image/jpeg;base64';

    /** @var string base64 png image type */

    const BASE64_PNG = 'data:image/png;base64';

    /** @var string base64 svg image type */

    const BASE64_SVG = 'data:image/svg+xml;base64';

    /** @var string base64 webp image type */

    const BASE64_WEBP = 'data:image/webp;base64';

    /** @var string base64 ico image type */

    const BASE64_ICO = 'data:image/x-icon;base64';

    /** @var null Generic object for data used in tool renderers/templates. */

    private $data = null;

    /** @var  filter Any filter being used for tool display. */

    private $filter;

    /** @var string Error message if there is one. */

    private $errormessage = '';

    /**

     * Get a mapping of tool shortname => class name.

     *

     * @return  string[]

     */

    protected static function get_tool_classnames(): array {

        $tools = [];

        foreach (self::TOOLNAMES as $toolname) {

            $tools[$toolname] = "tool_brickfield\\local\\tool\\{$toolname}";

        }

        return $tools;

    }

    /**

     * Return an array with one of each tool instance.

     *

     * @return tool[]

     */

    public static function build_all_accessibilitytools(): array {

        return array_map(function($classname) {

            return new $classname();

        }, self::get_tool_classnames());

    }

    /**

     * Get a list of formal tool names for each tool.

     *

     * @return  string[]

     */

    public static function get_tool_names(): array {

        return array_map(function($classname) {

            return $classname::toolname();

        }, self::get_tool_classnames());

    }

    /**

     * Provide a lowercase name identifying this plugin. Should really be the same as the directory name.

     * @return string

     */

    abstract public function pluginname();

    /**

     * Provide a name for this tool, suitable for display on pages.

     * @return mixed

     */

    abstract public static function toolname();

    /**

     * Provide a short name for this tool, suitable for menus and selectors.

     * @return mixed

     */

    abstract public static function toolshortname();

    /**

     * Fetch the data for renderer / template display. Classes must implement this.

     * @return \stdClass

     */

    abstract protected function fetch_data(): \stdClass;

    /**

     * Return the data needed for the renderer.

     * @return \stdClass

     * @throws \coding_exception

     */

    public function get_data(): \stdClass {

        if (!$this->filter) {

            throw new \coding_exception('Filter has not been set.');

        }

        if (empty($this->data)) {

            $this->data = $this->fetch_data();

        }

        return $this->data;

    }

    /**

     * Implementing class should set the 'valid' property when get_data is called.

     * @return bool

     */

    public function data_is_valid(): bool {

        $data = $this->get_data();

        return (!empty($data->valid));

    }

    /**

     * Implementing class should set an error string if data is invalidated in 'get_data';

     * @return string

     */

    public function data_error(): string {

        if (!$this->data_is_valid()) {

            return $this->data->error;

        } else {

            return '';

        }

    }

    /**

     * Setter for filter property.

     * @param filter $filter

     * @throws \coding_exception

     */

    public function set_filter(filter $filter): void {

        if ($this->filter) {

            throw new \coding_exception('Filter can only be set once.');

        }

        $this->filter = $filter;

    }

    /**

     * Getter for filter property.

     * @return filter|null

     */

    public function get_filter(): ?filter {

        return $this->filter;

    }

    /**

     * Returns the output target for this tool's filter.

     *

     * @return string

     * @throws \coding_exception

     */

    public function get_output_target() {

        $filter = $this->get_filter();

        if (!$filter) {

            throw new \coding_exception('Filter has not been set.');

        }

        return $filter->target;

    }

    /**

     * Get the HTML output for display.

     *

     * @return mixed

     */

    public function get_output() {

        global $PAGE;

        $data = $this->get_data();

        $filter = $this->get_filter();

        $renderer = $PAGE->get_renderer('tool_brickfield', $this->pluginname());

        return $renderer->display($data, $filter);

    }

    /**

     * Return the defined toolname.

     *

     * @return mixed

     */

    public function get_toolname(): string {

        return static::toolname();

    }

    /**

     * Return the defined toolshortname.

     *

     * @return mixed

     */

    public function get_toolshortname(): string {

        return static::toolshortname();

    }

    /**

     * Verify that accessibility tools can be accessed in the provided context.

     * @param filter $filter

     * @param \context $context

     * @return bool

     * @throws \coding_exception

     * @throws \dml_exception

     */

    public function can_access(filter $filter, ?\context $context = null): bool {

        return $filter->can_access($context);

    }

    /**

     * Return any defined error message.

     *

     * @return string

     */

    public function get_error_message(): string {

        return $this->errormessage;

    }

    /**

     * Get module label for display

     * @param string $modulename

     * @return string

     * @throws \coding_exception

     */

    public static function get_module_label(string $modulename): string {

        if (get_string_manager()->string_exists('pluginname', $modulename)) {

            $modulename = get_string('pluginname', $modulename);

        } else {

            $modulename = get_string($modulename, manager::PLUGINNAME);

        }

        return($modulename);

    }

    /**

     * Get instance name for display

     * @param string $component

     * @param string $table

     * @param int $cmid

     * @param int $courseid

     * @param int $categoryid

     * @return string

     */

    public static function get_instance_name(string $component, string $table, ?int $cmid, ?int $courseid,

        ?int $categoryid): string {

        global $DB;

        $instancename = '';

        if (empty($component)) {

            return $instancename;

        }

        if ($component == 'core_course') {

            if (($table == 'course_categories') && ($categoryid != 0) && ($categoryid != null)) {

                $instancename = $DB->get_field($table, 'name', ['id' => $categoryid]);

                return get_string('category') . ' - ' . $instancename;

            }

            if (($courseid == 0) || ($courseid == null)) {

                return $instancename;

            }

            $thiscourse = get_fast_modinfo($courseid)->get_course();

            $instancename = $thiscourse->shortname;

        } else if ($component == 'core_question') {

            $instancename = get_string('questions', 'question');

        } else {

            if (($cmid == 0) || ($cmid == null)) {

                return $instancename;

            }

            $cm = get_fast_modinfo($courseid)->cms[$cmid];

            $instancename = $cm->name;

        }

        $instancename = static::get_module_label($component).' - '.$instancename;

        return($instancename);

    }

    /**

     * Provide arguments required for the toplevel page, using any provided filter.

     * @param filter|null $filter

     * @return array

     */

    public static function toplevel_arguments(?filter $filter = null): array {

        if ($filter !== null) {

            return ['courseid' => $filter->courseid, 'categoryid' => $filter->categoryid];

        } else {

            return [];

        }

    }

    /**

     * Override this to return any tool specific perpage limits.

     * @param int $perpage

     * @return int

     */

    public function perpage_limits(int $perpage): int {

        return $perpage;

    }

    /**

     * Return array of base64 image formats.

     * @return array

     */

    public static function base64_img_array(): array {

        $base64 = [];

        $base64[] = self::BASE64_BMP;

        $base64[] = self::BASE64_GIF;

        $base64[] = self::BASE64_JPG;

        $base64[] = self::BASE64_PNG;

        $base64[] = self::BASE64_SVG;

        $base64[] = self::BASE64_WEBP;

        $base64[] = self::BASE64_ICO;

        return $base64;

    }

    /**

     * Detects if htmlcode contains base64 img data, for HTML display, such as errors page.

     * @param string $htmlcode

     * @return boolean

     */

    public static function base64_img_detected(string $htmlcode): bool {

        $detected = false;

        // Grab defined base64 img array.

        $base64 = self::base64_img_array();

        foreach ($base64 as $type) {

            // Need to detect this within an img tag.

            $pos = stripos($htmlcode, '<img src="'.$type);

            if ($pos !== false) {

                $detected = true;

                return $detected;

            }

        }

        return $detected;

    }

    /**

     * Truncate base64-containing htmlcode for HTML display, such as errors page.

     * @param string $htmlcode

     * @return string

     */

    public static function truncate_base64(string $htmlcode): string {

        $newhtmlcode = '';

        // Parse HTML by " characters.

        $sections = explode('"', $htmlcode);

        $base64 = self::base64_img_array();

        foreach ($sections as $section) {

            foreach ($base64 as $type) {

                $pos = stripos($section, $type);

                if ($pos !== false) {

                    $section = substr($section, 0, $pos + strlen($type)).'...';

                }

            }

            $newhtmlcode .= $section.'"';

        }

        return $newhtmlcode;

    }

    /**

     * Return the correct language string for the provided check.

     *

     * @param string $check

     * @return string

     */

    public static function get_check_description(string $check): string {

        return get_string('checkdesc:' . str_replace('_', '', $check), manager::PLUGINNAME);

    }

}