<?php

class Event extends DataObject
{
    private static $db = array(
        'Title' => 'Text'
    );

    private static $many_many = array(
        'EventArtists' => 'EventUser',
        'Genres' => 'Genre'
    );
}



class EventUser extends DataObject
{
    private static $belongs_many_many = array(
        'Events' => 'Event',
        'Users' => 'User'
    );
}



class Genre extends DataObject
{
    private static $db = array(
        'GenreName' => 'Text'
    );

    private static $belongs_many_many = array(
        'Events' => 'Event',
        'Users' => 'User'
    );
}

class EventPage_Controller extends Page_Controller
{
    private static $allowed_actions = array(
        'EventEditForm',
    );

    public function EventEditForm()
    {
        $title_field = TextField::create('Title', 'Title', $event->Title);

        $all_genres = Genre::get()->map('ID', 'GenreName')->toArray();
        $genres_field = ListboxField::create('Genres', 'Genres', $all_genres)->setMultiple(true);

        $all_artists = User::get()->filter(
            array('UserTypeID' => UserType::get()->filter(
                    array('UserTypeName' => UserType::getArtistUserTypeName())
                )->first()->ID)
        )->map('ID', 'FirstName')->toArray();

        $artists_field = ListboxField::create('EventArtists', 'Performing Artists', $all_artists)->setMultiple(true);

        $event_genres = $event->Genres()->column('ID');
        $genres_field->setValue($event_genres);

        $event_artists = $event->EventArtists()->column('ID');
        $artists_field->setValue($event_artists);

        $fields = new FieldList(
            $title_field,
            $genres_field,
            $artists_field
        );

        $actions = new FieldList(
            FormAction::create('submitEventEditForm', 'Submit')
        );

        $validator = new RequiredFields(
            'Title'
        );

        $form = Form::create($this, 'EventEditForm', $fields, $actions, $validator);

        return $form;
    }

    public function submitEventEditForm($data, $form)
    {
        $current_user = User::currentUser();
        $event_ID = $data['ID'];

        $event = Event::get()->filter(array(
            'ID' => $event_ID
        ))->first();

        $form->saveInto($event);

        // Update genres
        $genres = isset($data['Genres']) ? $data['Genres'] : array();

        foreach ($genres as $genre_ID) {
            $event->Genres()->add($genre_ID);
        }

        $event_artists = isset($data['EventArtists']) ? $data['EventArtists'] : array();

        foreach ($event_artists as $artist_ID) {
            $event->EventArtists()->add($artist_ID);
        }

        $event->write();

        return true;
    }
}