class TranslateEditForm

class TranslateEditForm extends TranslateFormBase {
    
    /**
     * {@inheritdoc}
     */
    public function getFormId() {
        return 'locale_translate_edit_form';
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildForm(array $form, FormStateInterface $form_state) {
        $filter_values = $this->translateFilterValues();
        $langcode = $filter_values['langcode'];
        $this->languageManager
            ->reset();
        $languages = $this->languageManager
            ->getLanguages();
        $language_name = isset($langcode) ? $languages[$langcode]->getName() : "- None -";
        $form['#attached']['library'][] = 'locale/drupal.locale.admin';
        $form['langcode'] = [
            '#type' => 'value',
            '#value' => $filter_values['langcode'],
        ];
        $form['strings'] = [
            '#type' => 'table',
            '#tree' => TRUE,
            '#language' => $language_name,
            '#header' => [
                $this->t('Source string'),
                $this->t('Translation for @language', [
                    '@language' => $language_name,
                ]),
            ],
            '#empty' => $this->t('No strings available.'),
            '#attributes' => [
                'class' => [
                    'locale-translate-edit-table',
                ],
            ],
        ];
        if (isset($langcode)) {
            $strings = $this->translateFilterLoadStrings();
            $plurals = $this->getNumberOfPlurals($langcode);
            foreach ($strings as $string) {
                // Cast into source string, will do for our purposes.
                $source = new SourceString($string);
                // Split source to work with plural values.
                $source_array = $source->getPlurals();
                $translation_array = $string->getPlurals();
                if (count($source_array) == 1) {
                    // Add original string value and mark as non-plural.
                    $plural = FALSE;
                    $form['strings'][$string->lid]['original'] = [
                        '#type' => 'item',
                        '#title' => $this->t('Source string (@language)', [
                            '@language' => $this->t('Built-in English'),
                        ]),
                        '#title_display' => 'invisible',
                        '#plain_text' => $source_array[0],
                        '#prefix' => '<span lang="en">',
                        '#suffix' => '</span>',
                    ];
                }
                else {
                    // Add original string value and mark as plural.
                    $plural = TRUE;
                    $original_singular = [
                        '#type' => 'item',
                        '#title' => $this->t('Singular form'),
                        '#plain_text' => $source_array[0],
                        '#prefix' => '<span class="visually-hidden">' . $this->t('Source string (@language)', [
                            '@language' => $this->t('Built-in English'),
                        ]) . '</span><span lang="en">',
                        '#suffix' => '</span>',
                    ];
                    $original_plural = [
                        '#type' => 'item',
                        '#title' => $this->t('Plural form'),
                        '#plain_text' => $source_array[1],
                        '#prefix' => '<span lang="en">',
                        '#suffix' => '</span>',
                    ];
                    $form['strings'][$string->lid]['original'] = [
                        $original_singular,
                        [
                            '#markup' => '<br>',
                        ],
                        $original_plural,
                    ];
                }
                if (!empty($string->context)) {
                    $form['strings'][$string->lid]['original'][] = [
                        '#type' => 'inline_template',
                        '#template' => '<br><small>{{ context_title }}: <span lang="en">{{ context }}</span></small>',
                        '#context' => [
                            'context_title' => $this->t('In Context'),
                            'context' => $string->context,
                        ],
                    ];
                }
                // Approximate the number of rows to use in the default textarea.
                $rows = min(ceil(str_word_count($source_array[0]) / 12), 10);
                if (!$plural) {
                    $form['strings'][$string->lid]['translations'][0] = [
                        '#type' => 'textarea',
                        '#title' => $this->t('Translated string (@language)', [
                            '@language' => $language_name,
                        ]),
                        '#title_display' => 'invisible',
                        '#rows' => $rows,
                        '#default_value' => $translation_array[0],
                        '#attributes' => [
                            'lang' => $langcode,
                        ],
                    ];
                }
                else {
                    // Add a textarea for each plural variant.
                    for ($i = 0; $i < $plurals; $i++) {
                        $form['strings'][$string->lid]['translations'][$i] = [
                            '#type' => 'textarea',
                            // @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'),
                            '#rows' => $rows,
                            '#default_value' => $translation_array[$i] ?? '',
                            '#attributes' => [
                                'lang' => $langcode,
                            ],
                            '#prefix' => $i == 0 ? '<span class="visually-hidden">' . $this->t('Translated string (@language)', [
                                '@language' => $language_name,
                            ]) . '</span>' : '',
                        ];
                    }
                    if ($plurals == 2) {
                        // Simplify interface text for the most common case.
                        $form['strings'][$string->lid]['translations'][1]['#title'] = $this->t('Plural form');
                    }
                }
            }
            if (count(Element::children($form['strings']))) {
                $form['actions'] = [
                    '#type' => 'actions',
                ];
                $form['actions']['submit'] = [
                    '#type' => 'submit',
                    '#value' => $this->t('Save translations'),
                ];
            }
        }
        $form['pager']['#type'] = 'pager';
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateForm(array &$form, FormStateInterface $form_state) {
        $langcode = $form_state->getValue('langcode');
        foreach ($form_state->getValue('strings') as $lid => $translations) {
            foreach ($translations['translations'] as $key => $value) {
                if (!locale_string_is_safe($value)) {
                    $form_state->setErrorByName("strings][{$lid}][translations][{$key}", $this->t('The submitted string contains disallowed HTML: %string', [
                        '%string' => $value,
                    ]));
                    $form_state->setErrorByName("translations][{$langcode}][{$key}", $this->t('The submitted string contains disallowed HTML: %string', [
                        '%string' => $value,
                    ]));
                    $this->logger('locale')
                        ->warning('Attempted submission of a translation string with disallowed HTML: %string', [
                        '%string' => $value,
                    ]);
                }
            }
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitForm(array &$form, FormStateInterface $form_state) {
        $langcode = $form_state->getValue('langcode');
        $updated = [];
        // Preload all translations for strings in the form.
        $lids = array_keys($form_state->getValue('strings'));
        $existing_translation_objects = [];
        foreach ($this->localeStorage
            ->getTranslations([
            'lid' => $lids,
            'language' => $langcode,
            'translated' => TRUE,
        ]) as $existing_translation_object) {
            $existing_translation_objects[$existing_translation_object->lid] = $existing_translation_object;
        }
        foreach ($form_state->getValue('strings') as $lid => $new_translation) {
            $existing_translation = isset($existing_translation_objects[$lid]);
            // Plural translations are saved in a delimited string. To be able to
            // compare the new strings with the existing strings a string in the same
            // format is created.
            $new_translation_string_delimited = implode(PoItem::DELIMITER, $new_translation['translations']);
            // Generate an imploded string without delimiter, to be able to run
            // empty() on it.
            $new_translation_string = implode('', $new_translation['translations']);
            $is_changed = FALSE;
            if ($existing_translation && $existing_translation_objects[$lid]->translation != $new_translation_string_delimited) {
                // If there is an existing translation in the DB and the new translation
                // is not the same as the existing one.
                $is_changed = TRUE;
            }
            elseif (!$existing_translation && !empty($new_translation_string)) {
                // Newly entered translation.
                $is_changed = TRUE;
            }
            if ($is_changed) {
                // Only update or insert if we have a value to use.
                $target = $existing_translation_objects[$lid] ?? $this->localeStorage
                    ->createTranslation([
                    'lid' => $lid,
                    'language' => $langcode,
                ]);
                $target->setPlurals($new_translation['translations'])
                    ->setCustomized()
                    ->save();
                $updated[] = $target->getId();
            }
            if (empty($new_translation_string) && isset($existing_translation_objects[$lid])) {
                // Empty new translation entered: remove existing entry from database.
                $existing_translation_objects[$lid]->delete();
                $updated[] = $lid;
            }
        }
        $this->messenger()
            ->addStatus($this->t('The strings have been saved.'));
        // Keep the user on the current pager page.
        $page = $this->getRequest()->query
            ->get('page');
        if (isset($page)) {
            $form_state->setRedirect('locale.translate_page', [], [
                'page' => $page,
            ]);
        }
        if ($updated) {
            // Clear cache and force refresh of JavaScript translations.
            _locale_refresh_translations([
                $langcode,
            ], $updated);
            _locale_refresh_configuration([
                $langcode,
            ], $updated);
        }
    }

}