class InOperator

class InOperator extends FilterPluginBase {
    protected $valueFormType = 'checkboxes';
    
    /**
     * @var array
     * Stores all operations which are available on the form.
     */
    protected $valueOptions = NULL;
    
    /**
     * The filter title.
     *
     * @var string
     */
    protected $valueTitle;
    
    /**
     * {@inheritdoc}
     */
    public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
        parent::init($view, $display, $options);
        $this->valueTitle = $this->t('Options');
        $this->valueOptions = NULL;
    }
    
    /**
     * Gets the value options.
     *
     * Child classes should be used to override this function and set the
     * 'value options', unless 'options callback' is defined as a valid function
     * or static public method to generate these values.
     *
     * This can use a guard to be used to reduce database hits as much as
     * possible.
     *
     * @return array|null
     *   The stored values from $this->valueOptions.
     */
    public function getValueOptions() {
        if (isset($this->valueOptions)) {
            return $this->valueOptions;
        }
        if (isset($this->definition['options callback']) && is_callable($this->definition['options callback'])) {
            if (isset($this->definition['options arguments']) && is_array($this->definition['options arguments'])) {
                $this->valueOptions = call_user_func_array($this->definition['options callback'], $this->definition['options arguments']);
            }
            else {
                $this->valueOptions = call_user_func($this->definition['options callback']);
            }
        }
        else {
            $this->valueOptions = [
                $this->t('Yes'),
                $this->t('No'),
            ];
        }
        return $this->valueOptions;
    }
    public function defaultExposeOptions() {
        parent::defaultExposeOptions();
        $this->options['expose']['reduce'] = FALSE;
    }
    public function buildExposeForm(&$form, FormStateInterface $form_state) {
        parent::buildExposeForm($form, $form_state);
        $form['expose']['reduce'] = [
            '#type' => 'checkbox',
            '#title' => $this->t('Limit list to selected items'),
            '#description' => $this->t('If checked, the only items presented to the user will be the ones selected here.'),
            // Safety.
'#default_value' => !empty($this->options['expose']['reduce']),
        ];
    }
    protected function defineOptions() {
        $options = parent::defineOptions();
        $options['operator']['default'] = 'in';
        $options['value']['default'] = [];
        $options['expose']['contains']['reduce'] = [
            'default' => FALSE,
        ];
        return $options;
    }
    
    /**
     * Gets the operators.
     *
     * This kind of construct makes it relatively easy for a child class
     * to add or remove functionality by overriding this function and
     * adding/removing items from this array.
     */
    public function operators() {
        $operators = [
            'in' => [
                'title' => $this->t('Is one of'),
                'short' => $this->t('in'),
                'short_single' => $this->t('='),
                'method' => 'opSimple',
                'values' => 1,
            ],
            'not in' => [
                'title' => $this->t('Is not one of'),
                'short' => $this->t('not in'),
                'short_single' => $this->t('<>'),
                'method' => 'opSimple',
                'values' => 1,
            ],
        ];
        // if the definition allows for the empty operator, add it.
        if (!empty($this->definition['allow empty'])) {
            $operators += [
                'empty' => [
                    'title' => $this->t('Is empty (NULL)'),
                    'method' => 'opEmpty',
                    'short' => $this->t('empty'),
                    'values' => 0,
                ],
                'not empty' => [
                    'title' => $this->t('Is not empty (NOT NULL)'),
                    'method' => 'opEmpty',
                    'short' => $this->t('not empty'),
                    'values' => 0,
                ],
            ];
        }
        return $operators;
    }
    
    /**
     * Build strings from the operators() for 'select' options.
     */
    public function operatorOptions($which = 'title') {
        $options = [];
        foreach ($this->operators() as $id => $info) {
            $options[$id] = $info[$which];
        }
        return $options;
    }
    protected function operatorValues($values = 1) {
        $options = [];
        foreach ($this->operators() as $id => $info) {
            if (isset($info['values']) && $info['values'] == $values) {
                $options[] = $id;
            }
        }
        return $options;
    }
    protected function valueForm(&$form, FormStateInterface $form_state) {
        $form['value'] = [];
        $options = [];
        $exposed = $form_state->get('exposed');
        if (!$exposed) {
            // Add a select all option to the value form.
            $options = [
                'all' => $this->t('Select all'),
            ];
        }
        $this->getValueOptions();
        $options += $this->valueOptions;
        $default_value = (array) $this->value;
        $which = 'all';
        if (!empty($form['operator'])) {
            $source = ':input[name="options[operator]"]';
        }
        if ($exposed) {
            $identifier = $this->options['expose']['identifier'];
            if (empty($this->options['expose']['use_operator']) || empty($this->options['expose']['operator_id'])) {
                // exposed and locked.
                $which = in_array($this->operator, $this->operatorValues(1)) ? 'value' : 'none';
            }
            else {
                $source = ':input[name="' . $this->options['expose']['operator_id'] . '"]';
            }
            if (!empty($this->options['expose']['reduce'])) {
                $options = $this->reduceValueOptions();
                if (!empty($this->options['expose']['multiple']) && empty($this->options['expose']['required'])) {
                    $default_value = [];
                }
            }
            if (empty($this->options['expose']['multiple'])) {
                if (empty($this->options['expose']['required']) && (empty($default_value) || !empty($this->options['expose']['reduce'])) || isset($this->options['value']['all'])) {
                    $default_value = 'All';
                }
                elseif (empty($default_value)) {
                    $keys = array_keys($options);
                    $default_value = array_shift($keys);
                }
                else {
                    $copy = $default_value;
                    $default_value = array_shift($copy);
                }
            }
        }
        if ($which == 'all' || $which == 'value') {
            $form['value'] = [
                '#type' => $this->valueFormType,
                '#title' => $this->valueTitle,
                '#options' => $options,
                '#default_value' => $default_value,
                // These are only valid for 'select' type, but do no harm to checkboxes.
'#multiple' => TRUE,
                // The value options can be a multidimensional array if the value form
                // type is a select list, so make sure that they are counted correctly.
'#size' => min(count($options, COUNT_RECURSIVE), 8),
            ];
            $user_input = $form_state->getUserInput();
            if ($exposed && !isset($user_input[$identifier])) {
                $user_input[$identifier] = $default_value;
                $form_state->setUserInput($user_input);
            }
            if ($which == 'all') {
                if (!$exposed && in_array($this->valueFormType, [
                    'checkbox',
                    'checkboxes',
                    'radios',
                    'select',
                ])) {
                    $form['value']['#prefix'] = '<div id="edit-options-value-wrapper">';
                    $form['value']['#suffix'] = '</div>';
                }
                // Setup #states for all operators with one value.
                foreach ($this->operatorValues(1) as $operator) {
                    $form['value']['#states']['visible'][] = [
                        $source => [
                            'value' => $operator,
                        ],
                    ];
                }
            }
        }
    }
    
    /**
     * When using exposed filters, we may be required to reduce the set.
     */
    public function reduceValueOptions($input = NULL) {
        if (!isset($input)) {
            $input = $this->valueOptions;
        }
        // Because options may be an array of strings, or an array of mixed arrays
        // and strings (optgroups), or an array of objects, or a form of Markup, we
        // have to step through and handle each one individually.
        $options = [];
        foreach ($input as $id => $option) {
            if (is_array($option)) {
                $options[$id] = $this->reduceValueOptions($option);
                continue;
            }
            elseif (is_object($option) && !$option instanceof MarkupInterface) {
                $keys = array_keys($option->option);
                $key = array_shift($keys);
                if (isset($this->options['value'][$key])) {
                    $options[$id] = $option;
                }
            }
            elseif (isset($this->options['value'][$id])) {
                $options[$id] = $option;
            }
        }
        return $options;
    }
    
    /**
     * {@inheritdoc}
     */
    public function acceptExposedInput($input) {
        if (empty($this->options['exposed'])) {
            return TRUE;
        }
        // The "All" state for this type of filter could have a default value. If
        // this is a non-multiple and non-required option, then this filter will
        // participate by using the default settings *if* 'limit' is true.
        if (empty($this->options['expose']['multiple']) && empty($this->options['expose']['required']) && !empty($this->options['expose']['limit'])) {
            $identifier = $this->options['expose']['identifier'];
            if ($input[$identifier] == 'All') {
                return TRUE;
            }
        }
        return parent::acceptExposedInput($input);
    }
    protected function valueSubmit($form, FormStateInterface $form_state) {
        // Drupal's FAPI system automatically puts '0' in for any checkbox that
        // was not set, and the key to the checkbox if it is set.
        // Unfortunately, this means that if the key to that checkbox is 0,
        // we are unable to tell if that checkbox was set or not.
        // Luckily, the '#value' on the checkboxes form actually contains
        // *only* a list of checkboxes that were set, and we can use that
        // instead.
        $form_state->setValue([
            'options',
            'value',
        ], $form['value']['#value']);
    }
    public function adminSummary() {
        if ($this->isAGroup()) {
            return $this->t('grouped');
        }
        if (!empty($this->options['exposed'])) {
            return $this->t('exposed');
        }
        $info = $this->operators();
        $this->getValueOptions();
        // Some filter_in_operator usage uses optgroups forms, so flatten it.
        $flat_options = OptGroup::flattenOptions($this->valueOptions);
        if (!is_array($this->value)) {
            return;
        }
        $operator = $info[$this->operator]['short'];
        $values = '';
        if (in_array($this->operator, $this->operatorValues(1))) {
            // Remove every element which is not known.
            foreach ($this->value as $value) {
                if (!isset($flat_options[$value])) {
                    unset($this->value[$value]);
                }
            }
            // Choose different kind of output for 0, a single and multiple values.
            if (count($this->value) == 0) {
                $values = $this->t('Unknown');
            }
            elseif (count($this->value) == 1) {
                // If any, use the 'single' short name of the operator instead.
                if (isset($info[$this->operator]['short_single'])) {
                    $operator = $info[$this->operator]['short_single'];
                }
                $keys = $this->value;
                $value = array_shift($keys);
                if (isset($flat_options[$value])) {
                    $values = $flat_options[$value];
                }
                else {
                    $values = '';
                }
            }
            else {
                foreach ($this->value as $value) {
                    if ($values !== '') {
                        $values .= ', ';
                    }
                    if (mb_strlen($values) > 8) {
                        $values = Unicode::truncate($values, 8, FALSE, TRUE);
                        break;
                    }
                    if (isset($flat_options[$value])) {
                        $values .= $flat_options[$value];
                    }
                }
            }
        }
        return $operator . ($values !== '' ? ' ' . $values : '');
    }
    public function query() {
        $info = $this->operators();
        if (!empty($info[$this->operator]['method'])) {
            $this->{$info[$this->operator]['method']}();
        }
    }
    protected function opSimple() {
        if (empty($this->value)) {
            return;
        }
        $this->ensureMyTable();
        // We use array_values() because the checkboxes keep keys and that can cause
        // array addition problems.
        $this->query
            ->addWhere($this->options['group'], "{$this->tableAlias}.{$this->realField}", array_values($this->value), $this->operator);
    }
    protected function opEmpty() {
        $this->ensureMyTable();
        if ($this->operator == 'empty') {
            $operator = "IS NULL";
        }
        else {
            $operator = "IS NOT NULL";
        }
        $this->query
            ->addWhere($this->options['group'], "{$this->tableAlias}.{$this->realField}", NULL, $operator);
    }
    public function validate() {
        $this->getValueOptions();
        $errors = parent::validate();
        // If the operator is an operator which doesn't require a value, there is
        // no need for additional validation.
        if (in_array($this->operator, $this->operatorValues(0))) {
            return [];
        }
        if (!in_array($this->operator, $this->operatorValues(1))) {
            $errors[] = $this->t('The operator is invalid on filter: @filter.', [
                '@filter' => $this->adminLabel(TRUE),
            ]);
        }
        if (is_array($this->value)) {
            if (!isset($this->valueOptions)) {
                // Don't validate if there are none value options provided, for example for special handlers.
                return $errors;
            }
            if ($this->options['exposed'] && !$this->options['expose']['required'] && empty($this->value)) {
                // Don't validate if the field is exposed and no default value is provided.
                return $errors;
            }
            // Some filter_in_operator usage uses optgroups forms, so flatten it.
            $flat_options = OptGroup::flattenOptions($this->valueOptions);
            // Remove every element which is not known.
            foreach ($this->value as $value) {
                if (!isset($flat_options[$value])) {
                    unset($this->value[$value]);
                }
            }
            // Choose different kind of output for 0, a single and multiple values.
            if (count($this->value) == 0) {
                $errors[] = $this->t('No valid values found on filter: @filter.', [
                    '@filter' => $this->adminLabel(TRUE),
                ]);
            }
        }
        elseif (!empty($this->value) && ($this->operator == 'in' || $this->operator == 'not in')) {
            $errors[] = $this->t('The value @value is not an array for @operator on filter: @filter', [
                '@value' => var_export($this->value, TRUE),
                '@operator' => $this->operator,
                '@filter' => $this->adminLabel(TRUE),
            ]);
        }
        return $errors;
    }

}