class NumericField

class NumericField extends FieldPluginBase {
    
    /**
     * {@inheritdoc}
     */
    protected function defineOptions() {
        $options = parent::defineOptions();
        $options['set_precision'] = [
            'default' => FALSE,
        ];
        $options['precision'] = [
            'default' => 0,
        ];
        $options['decimal'] = [
            'default' => '.',
        ];
        $options['separator'] = [
            'default' => ',',
        ];
        $options['format_plural'] = [
            'default' => FALSE,
        ];
        $options['format_plural_string'] = [
            'default' => '1' . PoItem::DELIMITER . '@count',
        ];
        $options['prefix'] = [
            'default' => '',
        ];
        $options['suffix'] = [
            'default' => '',
        ];
        return $options;
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildOptionsForm(&$form, FormStateInterface $form_state) {
        if (!empty($this->definition['float'])) {
            $form['set_precision'] = [
                '#type' => 'checkbox',
                '#title' => $this->t('Round'),
                '#description' => $this->t('If checked, the number will be rounded.'),
                '#default_value' => $this->options['set_precision'],
            ];
            $form['precision'] = [
                '#type' => 'textfield',
                '#title' => $this->t('Precision'),
                '#default_value' => $this->options['precision'],
                '#description' => $this->t('Specify how many digits to print after the decimal point.'),
                '#states' => [
                    'visible' => [
                        ':input[name="options[set_precision]"]' => [
                            'checked' => TRUE,
                        ],
                    ],
                ],
                '#size' => 2,
            ];
            $form['decimal'] = [
                '#type' => 'textfield',
                '#title' => $this->t('Decimal point'),
                '#default_value' => $this->options['decimal'],
                '#description' => $this->t('What single character to use as a decimal point.'),
                '#size' => 2,
            ];
        }
        $form['separator'] = [
            '#type' => 'select',
            '#title' => $this->t('Thousands marker'),
            '#options' => [
                '' => $this->t('- None -'),
                ',' => $this->t('Comma'),
                ' ' => $this->t('Space'),
                '.' => $this->t('Decimal'),
                '\'' => $this->t('Apostrophe'),
            ],
            '#default_value' => $this->options['separator'],
            '#description' => $this->t('What single character to use as the thousands separator.'),
            '#size' => 2,
        ];
        $form['format_plural'] = [
            '#type' => 'checkbox',
            '#title' => $this->t('Format plural'),
            '#description' => $this->t('If checked, special handling will be used for plurality.'),
            '#default_value' => $this->options['format_plural'],
        ];
        $form['format_plural_string'] = [
            '#type' => 'value',
            '#default_value' => $this->options['format_plural_string'],
        ];
        $plural_array = explode(PoItem::DELIMITER, $this->options['format_plural_string']);
        $plurals = $this->getNumberOfPlurals($this->view->storage
            ->get('langcode'));
        for ($i = 0; $i < $plurals; $i++) {
            $form['format_plural_values'][$i] = [
                '#type' => 'textfield',
                // @todo Should use better labels https://www.drupal.org/node/2499639
'#title' => $i == 0 ? $this->t('Singular form') : $this->formatPlural($i, 'First plural form', '@count. plural form'),
                '#default_value' => isset($plural_array[$i]) ? $plural_array[$i] : '',
                '#description' => $this->t('Text to use for this variant, @count will be replaced with the value.'),
                '#states' => [
                    'visible' => [
                        ':input[name="options[format_plural]"]' => [
                            'checked' => TRUE,
                        ],
                    ],
                ],
            ];
        }
        if ($plurals == 2) {
            // Simplify interface text for the most common case.
            $form['format_plural_values'][0]['#description'] = $this->t('Text to use for the singular form, @count will be replaced with the value.');
            $form['format_plural_values'][1]['#title'] = $this->t('Plural form');
            $form['format_plural_values'][1]['#description'] = $this->t('Text to use for the plural form, @count will be replaced with the value.');
        }
        $form['prefix'] = [
            '#type' => 'textfield',
            '#title' => $this->t('Prefix'),
            '#default_value' => $this->options['prefix'],
            '#description' => $this->t('Text to put before the number, such as currency symbol.'),
        ];
        $form['suffix'] = [
            '#type' => 'textfield',
            '#title' => $this->t('Suffix'),
            '#default_value' => $this->options['suffix'],
            '#description' => $this->t('Text to put after the number, such as currency symbol.'),
        ];
        parent::buildOptionsForm($form, $form_state);
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitOptionsForm(&$form, FormStateInterface $form_state) {
        // Merge plural format options into one string and drop the individual
        // option values.
        $options =& $form_state->getValue('options');
        $options['format_plural_string'] = implode(PoItem::DELIMITER, $options['format_plural_values']);
        unset($options['format_plural_values']);
        parent::submitOptionsForm($form, $form_state);
    }
    
    /**
     * {@inheritdoc}
     */
    public function render(ResultRow $values) {
        $value = $this->getValue($values);
        // Check to see if hiding should happen before adding prefix and suffix
        // and before rewriting.
        if ($this->options['hide_empty'] && empty($value) && ($value !== 0 || $this->options['empty_zero'])) {
            return '';
        }
        if (!empty($this->options['set_precision'])) {
            $precision = $this->options['precision'];
        }
        elseif ($decimal_position = strpos($value, '.')) {
            $precision = strlen($value) - $decimal_position - 1;
        }
        else {
            $precision = 0;
        }
        // Use round first to avoid negative zeros.
        $value = round($value, $precision);
        // Test against both integer zero and float zero.
        if ($this->options['empty_zero'] && ($value === 0 || $value === 0.0)) {
            return '';
        }
        $value = number_format($value, $precision, $this->options['decimal'], $this->options['separator']);
        // If we should format as plural, take the (possibly) translated plural
        // setting and format with the current language.
        if (!empty($this->options['format_plural'])) {
            $value = PluralTranslatableMarkup::createFromTranslatedString($value, $this->options['format_plural_string']);
        }
        return $this->sanitizeValue($this->options['prefix'], 'xss') . $this->sanitizeValue($value) . $this->sanitizeValue($this->options['suffix'], 'xss');
    }

}