<?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;

use coding_exception;
use core_reportbuilder\local\helpers\report;
use core_reportbuilder\local\models\column as column_model;
use core_reportbuilder\local\models\filter as filter_model;
use core_reportbuilder\local\report\base;
use core_reportbuilder\local\report\column;
use core_reportbuilder\local\report\filter;

/**
 * Class datasource
 *
 * @package   core_reportbuilder
 * @copyright 2021 David Matamoros <davidmc@moodle.com>
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
abstract class datasource extends base {


>     /** @var float[] $elementsmodified Track the time elements of specific reports have been added, updated, removed */
    /**
>     private static $elementsmodified = [];
     * Return user friendly name of the datasource
> 
     *
>     /** @var array $activecolumns */
     * @return string
>     private $activecolumns;
     */
> 
    abstract public static function get_name(): string;
>     /** @var array $activefilters */

>     private $activefilters;
    /**
> 
     * Add columns from the given entity name to be available to use in a custom report
>     /** @var array $activeconditions */
     *
>     private $activeconditions;
     * @param string $entityname
> 


     * @param array $include Include only these columns, if omitted then include all
     * @param array $exclude Exclude these columns, if omitted then exclude none
     * @throws coding_exception If both $include and $exclude are non-empty
     */
    final protected function add_columns_from_entity(string $entityname, array $include = [], array $exclude = []): void {
        if (!empty($include) && !empty($exclude)) {
            throw new coding_exception('Cannot specify columns to include and exclude simultaneously');
        }

        $entity = $this->get_entity($entityname);

        // Retrieve filtered columns from entity, respecting given $include/$exclude parameters.
        $columns = array_filter($entity->get_columns(), static function(column $column) use ($include, $exclude): bool {
            if (!empty($include)) {
                return in_array($column->get_name(), $include);
            }

            if (!empty($exclude)) {
                return !in_array($column->get_name(), $exclude);
            }

            return true;
        });

        foreach ($columns as $column) {
            $this->add_column($column);
        }
    }

    /**
     * Add default datasource columns to the report
     *

<      * This method is optional and can be called when the report is created to add the default columns defined in the
<      * selected datasource.



>      * Uses column data returned by the source {@see get_default_columns} and {@see get_default_column_sorting} methods
>      *
>      * @throws coding_exception If default column sorting refers to an invalid column


     */
    public function add_default_columns(): void {
        $reportid = $this->get_report_persistent()->get('id');

> 
        $columnidentifiers = $this->get_default_columns();
>         // Retrieve default column sorting, and track index of both sorted/non-sorted columns.


        foreach ($columnidentifiers as $uniqueidentifier) {

> 
            report::add_report_column($reportid, $uniqueidentifier);
>         $defaultcolumnsorting = $this->get_default_column_sorting();
        }
>         $defaultcolumnsortinginvalid = array_diff_key($defaultcolumnsorting,
    }
>             array_fill_keys($columnidentifiers, 1));

> 
    /**
>         if (count($defaultcolumnsortinginvalid) > 0) {
     * Return the columns that will be added to the report once is created
>             throw new coding_exception('Invalid column name', array_key_first($defaultcolumnsortinginvalid));
     *
>         }
     * @return string[]
> 
     */
>         $columnnonsortingindex = count($defaultcolumnsorting) + 1;
    abstract public function get_default_columns(): array;
> 



<             report::add_report_column($reportid, $uniqueidentifier);



>             $column = report::add_report_column($reportid, $uniqueidentifier);
> 
>             // After adding the column, toggle sorting according to defaults provided by the datasource.
>             $sortorder = array_search($uniqueidentifier, array_keys($defaultcolumnsorting));
>             if ($sortorder !== false) {
>                 $column->set_many([
>                     'sortenabled' => true,
>                     'sortdirection' => $defaultcolumnsorting[$uniqueidentifier],
>                     'sortorder' => $sortorder + 1,
>                 ])->update();
>             } else if (!empty($defaultcolumnsorting)) {
>                 $column->set('sortorder', $columnnonsortingindex++)->update();
>             }



<      * Return the columns that will be added to the report once is created



>      * Return the default columns that will be added to the report upon creation, by {@see add_default_columns}



<      * Return all configured report columns



>      * Return the default column sorting that will be set for the report upon creation, by {@see add_default_columns}
>      *
>      * When overriding this method in child classes, column identifiers specified must refer to default columns returned from
>      * the {@see get_default_columns} method
>      *
>      * @return int[] array [column identifier => SORT_ASC/SORT_DESC]
>      */
>     public function get_default_column_sorting(): array {
>         return [];
>     }
> 
>     /**
>      * Override parent method, returning only those columns specifically added to the custom report (rather than all that are
>      * available)


     *
     * @return column[]
     */
    public function get_active_columns(): array {

<         $columns = [];



>         $reportid = $this->get_report_persistent()->get('id');
> 
>         // Determine whether we already retrieved the columns since the report was last modified.
>         self::$elementsmodified += [$reportid => -1];
>         if ($this->activecolumns !== null && $this->activecolumns['builttime'] > self::$elementsmodified[$reportid]) {
>             return $this->activecolumns['values'];
>         }
> 
>         $this->activecolumns = ['builttime' => microtime(true), 'values' => []];




<         $activecolumns = column_model::get_records(['reportid' => $this->get_report_persistent()->get('id')], 'columnorder');



>         $activecolumns = column_model::get_records(['reportid' => $reportid], 'columnorder');


        foreach ($activecolumns as $index => $column) {
            $instance = $this->get_column($column->get('uniqueidentifier'));

> 
            if ($instance !== null && $instance->get_is_available()) {
>             // Ensure the column is still present and available.



<                 $instance->set_persistent($column);



>                 if ($instance->get_is_deprecated()) {
>                     debugging("The column '{$instance->get_unique_identifier()}' is deprecated, please do not use it any more." .
>                         " {$instance->get_is_deprecated_message()}", DEBUG_DEVELOPER);
>                 }



                // We should clone the report column to ensure if it's added twice to a report, each operates independently.

<                 $columns[] = clone $instance



>                 $this->activecolumns['values'][] = clone $instance


                    ->set_index($index)

>                     ->set_persistent($column)


                    ->set_aggregation($column->get('aggregation'));
            }
        }


<         return $columns;



>         return $this->activecolumns['values'];


    }

    /**
     * Add filters from the given entity name to be available to use in a custom report
     *
     * @param string $entityname
     * @param array $include Include only these filters, if omitted then include all
     * @param array $exclude Exclude these filters, if omitted then exclude none
     * @throws coding_exception If both $include and $exclude are non-empty
     */
    final protected function add_filters_from_entity(string $entityname, array $include = [], array $exclude = []): void {
        if (!empty($include) && !empty($exclude)) {
            throw new coding_exception('Cannot specify filters to include and exclude simultaneously');
        }

        $entity = $this->get_entity($entityname);

        // Retrieve filtered filters from entity, respecting given $include/$exclude parameters.
        $filters = array_filter($entity->get_filters(), static function(filter $filter) use ($include, $exclude): bool {
            if (!empty($include)) {
                return in_array($filter->get_name(), $include);
            }

            if (!empty($exclude)) {
                return !in_array($filter->get_name(), $exclude);
            }

            return true;
        });

        foreach ($filters as $filter) {
            $this->add_filter($filter);
        }
    }

    /**
     * Add default datasource filters to the report
     *
     * This method is optional and can be called when the report is created to add the default filters defined in the
     * selected datasource.
     */
    public function add_default_filters(): void {
        $reportid = $this->get_report_persistent()->get('id');
        $filteridentifiers = $this->get_default_filters();
        foreach ($filteridentifiers as $uniqueidentifier) {
            report::add_report_filter($reportid, $uniqueidentifier);
        }
    }

    /**
     * Return the filters that will be added to the report once is created
     *
     * @return string[]
     */
    abstract public function get_default_filters(): array;

    /**

<      * Return all configured report filters



>      * Override parent method, returning only those filters specifically added to the custom report (rather than all that are
>      * available)


     *
     * @return filter[]
     */
    public function get_active_filters(): array {

<         $filters = [];



>         $reportid = $this->get_report_persistent()->get('id');
> 
>         // Determine whether we already retrieved the filters since the report was last modified.
>         self::$elementsmodified += [$reportid => -1];
>         if ($this->activefilters !== null && $this->activefilters['builttime'] > self::$elementsmodified[$reportid]) {
>             return $this->activefilters['values'];
>         }
> 
>         $this->activefilters = ['builttime' => microtime(true), 'values' => []];




<         $activefilters = filter_model::get_filter_records($this->get_report_persistent()->get('id'), 'filterorder');



>         $activefilters = filter_model::get_filter_records($reportid, 'filterorder');


        foreach ($activefilters as $filter) {
            $instance = $this->get_filter($filter->get('uniqueidentifier'));

> 
            if ($instance !== null && $instance->get_is_available()) {
>             // Ensure the filter is still present and available.



<                 $filters[$instance->get_unique_identifier()] = $instance
<                     ->set_persistent($filter);



>                 if ($instance->get_is_deprecated()) {
>                     debugging("The filter '{$instance->get_unique_identifier()}' is deprecated, please do not use it any more." .
>                         " {$instance->get_is_deprecated_message()}", DEBUG_DEVELOPER);
>                 }
> 
>                 $this->activefilters['values'][$instance->get_unique_identifier()] =
>                     $instance->set_persistent($filter);


            }
        }


<         return $filters;



>         return $this->activefilters['values'];


    }

    /**
     * Add conditions from the given entity name to be available to use in a custom report
     *
     * @param string $entityname
     * @param array $include Include only these conditions, if omitted then include all
     * @param array $exclude Exclude these conditions, if omitted then exclude none
     * @throws coding_exception If both $include and $exclude are non-empty
     */
    final protected function add_conditions_from_entity(string $entityname, array $include = [], array $exclude = []): void {
        if (!empty($include) && !empty($exclude)) {
            throw new coding_exception('Cannot specify conditions to include and exclude simultaneously');
        }

        $entity = $this->get_entity($entityname);

        // Retrieve filtered conditions from entity, respecting given $include/$exclude parameters.
        $conditions = array_filter($entity->get_conditions(), static function(filter $condition) use ($include, $exclude): bool {
            if (!empty($include)) {
                return in_array($condition->get_name(), $include);
            }

            if (!empty($exclude)) {
                return !in_array($condition->get_name(), $exclude);
            }

            return true;
        });

        foreach ($conditions as $condition) {
            $this->add_condition($condition);
        }
    }

    /**
     * Add default datasource conditions to the report
     *
     * This method is optional and can be called when the report is created to add the default conditions defined in the
     * selected datasource.
     */
    public function add_default_conditions(): void {
        $reportid = $this->get_report_persistent()->get('id');
        $conditionidentifiers = $this->get_default_conditions();
        foreach ($conditionidentifiers as $uniqueidentifier) {
            report::add_report_condition($reportid, $uniqueidentifier);
        }

> 
    }
>         // Set the default condition values if they have been set in the datasource.

>         $this->set_condition_values($this->get_default_condition_values());


    /**
     * Return the conditions that will be added to the report once is created
     *
     * @return string[]
     */
    abstract public function get_default_conditions(): array;

    /**

<      * Return all configured report conditions



>      * Return the default condition values that will be added to the report once is created
>      *
>      * For any of the default conditions returned by the method {@see get_default_conditions} is
>      * possible to set the initial values.
>      *
>      * @return array
>      */
>     public function get_default_condition_values(): array {
>         return [];
>     }
> 
>     /**
>      * Override parent method, returning only those conditions specifically added to the custom report (rather than all that are
>      * available)


     *
     * @return filter[]
     */
    public function get_active_conditions(): array {

<         $conditions = [];



>         $reportid = $this->get_report_persistent()->get('id');
> 
>         // Determine whether we already retrieved the conditions since the report was last modified.
>         self::$elementsmodified += [$reportid => -1];
>         if ($this->activeconditions !== null && $this->activeconditions['builttime'] > self::$elementsmodified[$reportid]) {
>             return $this->activeconditions['values'];
>         }
> 
>         $this->activeconditions = ['builttime' => microtime(true), 'values' => []];




<         $activeconditions = filter_model::get_condition_records($this->get_report_persistent()->get('id'), 'filterorder');



>         $activeconditions = filter_model::get_condition_records($reportid, 'filterorder');


        foreach ($activeconditions as $condition) {
            $instance = $this->get_condition($condition->get('uniqueidentifier'));

> 
            if ($instance !== null && $instance->get_is_available()) {
>             // Ensure the condition is still present and available.



<                 $conditions[$instance->get_unique_identifier()] = $instance->set_persistent($condition);



>                 if ($instance->get_is_deprecated()) {
>                     debugging("The condition '{$instance->get_unique_identifier()}' is deprecated, please do not use it any more." .
>                         " {$instance->get_is_deprecated_message()}", DEBUG_DEVELOPER);
>                 }
> 
>                 $this->activeconditions['values'][$instance->get_unique_identifier()] =
>                     $instance->set_persistent($condition);


            }
        }


<         return $conditions;



>         return $this->activeconditions['values'];
>     }
> 
>     /**
>      * Adds all columns/filters/conditions from the given entity to the report at once
>      *
>      * @param string $entityname
>      */
>     final protected function add_all_from_entity(string $entityname): void {
>         $this->add_columns_from_entity($entityname);
>         $this->add_filters_from_entity($entityname);
>         $this->add_conditions_from_entity($entityname);
>     }
> 
>     /**
>      * Adds all columns/filters/conditions from all the entities added to the report at once
>      */
>     final protected function add_all_from_entities(): void {
>         foreach ($this->get_entities() as $entity) {
>             $this->add_all_from_entity($entity->get_entity_name());
>         }
>     }
> 
>     /**
>      * Indicate that report elements have been modified, e.g. columns/filters/conditions have been added, removed or updated
>      *
>      * @param int $reportid
>      */
>     final public static function report_elements_modified(int $reportid): void {
>         self::$elementsmodified[$reportid] = microtime(true);


    }
}