<?php

    namespace common\models;

    use Yii;
    use yii\base\Model;
    use yii\data\ActiveDataProvider;
    use yii\data\Pagination;
    use yii\data\Sort;

    /**
     * UserSearch represents the model behind the search form about `common\models\User`.
     */
    class UserSearch extends User
    {

        public $name_search;

        public $surname_search;

        public $specialization;

        /**
         * @inheritdoc
         */
        public function rules()
        {
            return [
                [
                    [ 'id' ],
                    'integer',
                    'min' => 1,
                ],
                [
                    [
                        'name_search',
                        'surname_search',
                        'specialization',
                    ],
                    'safe',
                ],
            ];
        }

        /**
         * @inheritdoc
         */
        public function scenarios()
        {
            return Model::scenarios();
        }

        /**
         * Creates data provider instance with search query applied
         *
         * @param array $params
         *
         * @return ActiveDataProvider
         */
        public function search($params)
        {
            $query = User::find()
                         ->joinWith('userInfo');

            $dataProvider = new ActiveDataProvider([
                'query' => $query,
                'pagination' => new Pagination([
                    'pageSize' => 5,
                ]),
                'sort' => new Sort([
                    'defaultOrder' => [
                        'id' => SORT_ASC,
                    ],
                ]),
            ]);

            $this->load($params);

            if(!$this->validate()) {
                // uncomment the following line if you do not want to return any records when validation fails
                // $query->where('0=1');
                return $dataProvider;
            }

            if(!empty( $this->specialization )) {
                $specialization_id = User::find()
                                         ->joinWith('specializations')
                                         ->select(['user.id'], 'DISTINCT')
                                         ->where([
                                             'like',
                                             'LOWER(specialization.specialization_name)',
                                             mb_strtolower($this->specialization),
                                         ])
                                         ->asArray()
                                         ->column();
                $query->andWhere(['user.id' => $specialization_id]);
            }

            $query->andFilterWhere([
                'id' => $this->id,
            ]);

            $query->andFilterWhere([
                'like',
                'LOWER(firstname)',
                mb_strtolower($this->name_search),
            ])
                  ->andFilterWhere([
                      'like',
                      'LOWER(lastname)',
                      mb_strtolower($this->surname_search),
                  ]);

            return $dataProvider;
        }
    }