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/>.

declare(strict_types=1);

namespace core_reportbuilder\local\helpers;

use core\lang_string;

use core_customfield\data_controller;

use core_customfield\field_controller;

use core_customfield\handler;

use core_reportbuilder\local\filters\{boolean_select, date, number, select, text};

use core_reportbuilder\local\report\{column, filter};

use stdClass;

/**

 * Helper class for course custom fields.

 *

 * @package   core_reportbuilder

 * @copyright 2021 Sara Arjona <sara@moodle.com> based on David Matamoros <davidmc@moodle.com> code.

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

 */

class custom_fields {

    use join_trait;

    /** @var handler $handler The handler for the customfields */

    private handler $handler;

    /**

     * Constructor

     *

     * @param string $tablefieldalias The table/field alias to match the instance ID when adding columns and filters.

     * @param string $entityname The entity name used when adding columns and filters.

     * @param string $component component name of full frankenstyle plugin name.

     * @param string $area name of the area (each component/plugin may define handlers for multiple areas).

     * @param int $itemid item id if the area uses them (usually not used).

     */

    public function __construct(

        /** @var string The table/field alias to match the instance ID when adding columns and filters */

        private readonly string $tablefieldalias,

        /** @var string The entity name used when adding columns and filters */

        private readonly string $entityname,

        string $component,

        string $area,

        int $itemid = 0,

    ) {

        $this->handler = handler::get_handler($component, $area, $itemid);

    }

    /**

     * Get table alias for given custom field

     *

     * The entity name is used to ensure the alias differs when the entity is used multiple times within the same report, each

     * having their own table alias/join

     *

     * @param field_controller $field

     * @return string

     */

    private function get_table_alias(field_controller $field): string {

        static $aliases = [];

        $aliaskey = "{$this->entityname}_{$field->get('id')}";

        if (!array_key_exists($aliaskey, $aliases)) {

            $aliases[$aliaskey] = database::generate_alias();

        }

        return $aliases[$aliaskey];

    }

    /**

     * Get table join for given custom field

     *

     * @param field_controller $field

     * @return string

     */

    private function get_table_join(field_controller $field): string {

        $customdatatablealias = $this->get_table_alias($field);

        return "LEFT JOIN {customfield_data} {$customdatatablealias}

                       ON {$customdatatablealias}.fieldid = {$field->get('id')}

                      AND {$customdatatablealias}.instanceid = {$this->tablefieldalias}";

    }

    /**

     * Gets the custom fields columns for the report.

     *

     * Column will be named as 'customfield_' + customfield shortname.

     *

     * @return column[]

     */

    public function get_columns(): array {

        $columns = [];

        $categorieswithfields = $this->handler->get_categories_with_fields();

        foreach ($categorieswithfields as $fieldcategory) {

            $categoryfields = $fieldcategory->get_fields();

            foreach ($categoryfields as $field) {

                $datacontroller = data_controller::create(0, null, $field);

                $datafield = $datacontroller->datafield();

                $customdatatablealias = $this->get_table_alias($field);

                $customdatasql = "{$customdatatablealias}.{$datafield}";

                // Numeric column (non-text) should coalesce with default, for aggregation.

                $columntype = $this->get_column_type($field, $datafield);

                if (!in_array($columntype, [column::TYPE_TEXT, column::TYPE_LONGTEXT])) {

                    // See MDL-78783 regarding no bound parameters, and SQL Server limitations of GROUP BY.

                    $customdatasql = "

                        CASE WHEN {$this->tablefieldalias} IS NOT NULL

                             THEN COALESCE({$customdatasql}, " . (float) $datacontroller->get_default_value() . ")

                             ELSE NULL

                        END";

                }

                // Select enough fields to re-create and format each custom field instance value.

                $customdatasqlextra = "{$customdatatablealias}.id, {$customdatatablealias}.contextid";

                if ($datafield === 'value') {

                    // We will take the format into account when displaying the individual values.

                    $customdatasqlextra .= ", {$customdatatablealias}.valueformat, {$customdatatablealias}.valuetrust";

                }

                $columns[] = (new column(

                    'customfield_' . $field->get('shortname'),

                    new lang_string('customfieldcolumn', 'core_reportbuilder', $field->get_formatted_name(false)),

                    $this->entityname

                ))

                    ->add_joins($this->get_joins())

                    ->add_join($this->get_table_join($field))

                    ->set_type($columntype)

                    ->add_field($customdatasql, $datafield)

                    ->add_fields($customdatasqlextra)

                    ->add_field($this->tablefieldalias, 'tablefieldalias')

                    ->set_is_sortable(true)

                    ->add_callback(static function($value, stdClass $row, field_controller $field, ?string $aggregation): string {

                        if ($row->tablefieldalias === null && $value === null) {

                            return '';

                        }

                        // If aggregating numeric column, populate row ID to ensure the controller is created correctly.

                        if (in_array((string) $aggregation, ['avg', 'max', 'min', 'sum'])) {

                            $row->id ??= -1;

                        }

                        return (string) data_controller::create(0, $row, $field)->export_value();

                    }, $field)

                    // Important. If the handler implements can_view() function, it will be called with parameter $instanceid=0.

                    // This means that per-instance access validation will be ignored.

                    ->set_is_available($this->handler->can_view($field, 0));

            }

        }

        return $columns;

    }

    /**

     * Returns the column type

     *

     * @param field_controller $field

     * @param string $datafield

     * @return int

     */

    private function get_column_type(field_controller $field, string $datafield): int {

        if ($field->get('type') === 'checkbox') {

            return column::TYPE_BOOLEAN;

        }

        if ($field->get('type') === 'date') {

            return column::TYPE_TIMESTAMP;

        }

        if ($field->get('type') === 'select') {

            return column::TYPE_TEXT;

        }

        if ($datafield === 'intvalue') {

            return column::TYPE_INTEGER;

        }

        if ($datafield === 'decvalue') {

            return column::TYPE_FLOAT;

        }

        if ($datafield === 'value') {

            return column::TYPE_LONGTEXT;

        }

        return column::TYPE_TEXT;

    }

    /**

     * Returns all available filters on custom fields.

     *

     * Filter will be named as 'customfield_' + customfield shortname.

     *

     * @return filter[]

     */

    public function get_filters(): array {

        $filters = [];

        $categorieswithfields = $this->handler->get_categories_with_fields();

        foreach ($categorieswithfields as $fieldcategory) {

            $categoryfields = $fieldcategory->get_fields();

            foreach ($categoryfields as $field) {

                $datacontroller = data_controller::create(0, null, $field);

                $datafield = $datacontroller->datafield();

                $customdatatablealias = $this->get_table_alias($field);

                $customdatasql = "{$customdatatablealias}.{$datafield}";

                $customdataparams = [];

                // Account for field default value, when joined to the instance table related to the custom fields.

                if (($fielddefault = $datacontroller->get_default_value()) !== null) {

                    $paramdefault = database::generate_param_name();

                    $customdatasql = "

                        CASE WHEN {$this->tablefieldalias} IS NOT NULL

                             THEN COALESCE({$customdatasql}, :{$paramdefault})

                             ELSE NULL

                        END";

                    $customdataparams[$paramdefault] = $fielddefault;

                }

                $filter = (new filter(

                    $this->get_filter_class_type($datacontroller),

                    'customfield_' . $field->get('shortname'),

                    new lang_string('customfieldcolumn', 'core_reportbuilder', $field->get_formatted_name(false)),

                    $this->entityname,

                    $customdatasql,

                    $customdataparams,

                ))

                    ->add_joins($this->get_joins())

                    ->add_join($this->get_table_join($field))

                    ->set_is_available($this->handler->can_view($field, 0));

                // If using a select filter, then populate the options.

                if ($filter->get_filter_class() === select::class) {

                    $filter->set_options_callback(fn(): array => $field->get_options());

                }

                $filters[] = $filter;

            }

        }

        return $filters;

    }

    /**

     * Returns class for the filter element that should be used for the field

     *

     * In some situation we can assume what kind of data is stored in the customfield plugin and we can

     * display appropriate filter form element. For all others assume text filter.

     *

     * @param data_controller $datacontroller

     * @return string

     */

    private function get_filter_class_type(data_controller $datacontroller): string {

        $type = $datacontroller->get_field()->get('type');

        switch ($type) {

            case 'checkbox':

                $classtype = boolean_select::class;

                break;

            case 'date':

                $classtype = date::class;

                break;

            case 'select':

                $classtype = select::class;

                break;

            default:

                // To support third party field type we need to account for stored numbers.

                $datafield = $datacontroller->datafield();

                if ($datafield === 'intvalue' || $datafield === 'decvalue') {

                    $classtype = number::class;

                } else {

                    $classtype = text::class;

                }

                break;

        }

        return $classtype;

    }

}