class PreviewTest

class PreviewTest extends WebDriverTestBase {
    
    /**
     * Views used by this test.
     *
     * @var array
     */
    public static $testViews = [
        'test_preview',
        'test_pager_full_ajax',
        'test_mini_pager_ajax',
        'test_click_sort_ajax',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected static $modules = [
        'node',
        'views',
        'views_ui',
        'views_test_config',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected $defaultTheme = 'stark';
    
    /**
     * {@inheritdoc}
     */
    public function setUp() : void {
        parent::setUp();
        ViewTestData::createTestViews(self::class, [
            'views_test_config',
        ]);
        $this->enableViewsTestModule();
        $admin_user = $this->drupalCreateUser([
            'administer site configuration',
            'administer views',
            'administer nodes',
            'access content overview',
        ]);
        // Disable automatic live preview to make the sequence of calls clearer.
        \Drupal::configFactory()->getEditable('views.settings')
            ->set('ui.always_live_preview', FALSE)
            ->save();
        $this->drupalLogin($admin_user);
    }
    
    /**
     * Sets up the views_test_data.module.
     *
     * Because the schema of views_test_data.module is dependent on the test
     * using it, it cannot be enabled normally.
     */
    protected function enableViewsTestModule() {
        // Define the schema and views data variable before enabling the test module.
        \Drupal::state()->set('views_test_data_schema', $this->schemaDefinition());
        \Drupal::state()->set('views_test_data_views_data', $this->viewsData());
        \Drupal::service('module_installer')->install([
            'views_test_data',
        ]);
        $this->resetAll();
        $this->rebuildContainer();
        $this->container
            ->get('module_handler')
            ->reload();
        // Load the test dataset.
        $data_set = $this->dataSet();
        $query = Database::getConnection()->insert('views_test_data')
            ->fields(array_keys($data_set[0]));
        foreach ($data_set as $record) {
            $query->values($record);
        }
        $query->execute();
    }
    
    /**
     * Returns the schema definition.
     *
     * @internal
     */
    protected function schemaDefinition() {
        return ViewTestData::schemaDefinition();
    }
    
    /**
     * Returns the views data definition.
     */
    protected function viewsData() {
        return ViewTestData::viewsData();
    }
    
    /**
     * Returns a very simple test dataset.
     */
    protected function dataSet() {
        return ViewTestData::dataSet();
    }
    
    /**
     * Tests the taxonomy term preview AJAX.
     *
     * This tests a specific regression in the taxonomy term view preview.
     *
     * @see https://www.drupal.org/node/2452659
     */
    public function testTaxonomyAJAX() {
        \Drupal::service('module_installer')->install([
            'taxonomy',
        ]);
        $this->getPreviewAJAX('taxonomy_term', 'page_1', 0);
    }
    
    /**
     * Tests pagers in the preview form.
     */
    public function testPreviewWithPagersUI() {
        // Create 11 nodes and make sure that everyone is returned.
        $this->drupalCreateContentType([
            'type' => 'page',
        ]);
        for ($i = 0; $i < 11; $i++) {
            $this->drupalCreateNode();
        }
        // Test Full Pager.
        $this->getPreviewAJAX('test_pager_full_ajax', 'default', 5);
        // Test that the pager is present and rendered.
        $elements = $this->xpath('//ul[contains(@class, "pager__items")]/li');
        $this->assertNotEmpty($elements);
        // Verify elements and links to pages.
        // We expect to find 5 elements: current page == 1, links to pages 2 and
        // and 3, links to 'next >' and 'last >>' pages.
        $this->assertClass($elements[0], 'is-active', 'Element for current page has .is-active class.');
        $this->assertNotEmpty($elements[0]->find('css', 'a'), 'Element for current page has link.');
        $this->assertClass($elements[1], 'pager__item', 'Element for page 2 has .pager__item class.');
        $this->assertNotEmpty($elements[1]->find('css', 'a'), 'Link to page 2 found.');
        $this->assertClass($elements[2], 'pager__item', 'Element for page 3 has .pager__item class.');
        $this->assertNotEmpty($elements[2]->find('css', 'a'), 'Link to page 3 found.');
        $this->assertClass($elements[3], 'pager__item--next', 'Element for next page has .pager__item--next class.');
        $this->assertNotEmpty($elements[3]->find('css', 'a'), 'Link to next page found.');
        $this->assertClass($elements[4], 'pager__item--last', 'Element for last page has .pager__item--last class.');
        $this->assertNotEmpty($elements[4]->find('css', 'a'), 'Link to last page found.');
        // Navigate to next page.
        $element = $this->assertSession()
            ->elementExists('xpath', '//li[contains(@class, "pager__item--next")]/a');
        $this->clickPreviewLinkAJAX($element, 5);
        // Test that the pager is present and rendered.
        $elements = $this->xpath('//ul[contains(@class, "pager__items")]/li');
        $this->assertNotEmpty($elements);
        // Verify elements and links to pages.
        // We expect to find 7 elements: links to '<< first' and '< previous'
        // pages, link to page 1, current page == 2, link to page 3 and links
        // to 'next >' and 'last >>' pages.
        $this->assertClass($elements[0], 'pager__item--first', 'Element for first page has .pager__item--first class.');
        $this->assertNotEmpty($elements[0]->find('css', 'a'), 'Link to first page found.');
        $this->assertClass($elements[1], 'pager__item--previous', 'Element for previous page has .pager__item--previous class.');
        $this->assertNotEmpty($elements[1]->find('css', 'a'), 'Link to previous page found.');
        $this->assertClass($elements[2], 'pager__item', 'Element for page 1 has .pager__item class.');
        $this->assertNotEmpty($elements[2]->find('css', 'a'), 'Link to page 1 found.');
        $this->assertClass($elements[3], 'is-active', 'Element for current page has .is-active class.');
        $this->assertNotEmpty($elements[3]->find('css', 'a'), 'Element for current page has link.');
        $this->assertClass($elements[4], 'pager__item', 'Element for page 3 has .pager__item class.');
        $this->assertNotEmpty($elements[4]->find('css', 'a'), 'Link to page 3 found.');
        $this->assertClass($elements[5], 'pager__item--next', 'Element for next page has .pager__item--next class.');
        $this->assertNotEmpty($elements[5]->find('css', 'a'), 'Link to next page found.');
        $this->assertClass($elements[6], 'pager__item--last', 'Element for last page has .pager__item--last class.');
        $this->assertNotEmpty($elements[6]->find('css', 'a'), 'Link to last page found.');
        // Test Mini Pager.
        $this->getPreviewAJAX('test_mini_pager_ajax', 'default', 3);
        // Test that the pager is present and rendered.
        $elements = $this->xpath('//ul[contains(@class, "pager__items")]/li');
        $this->assertNotEmpty($elements);
        // Verify elements and links to pages.
        // We expect to find current pages element with no link, next page element
        // with a link, and not to find previous page element.
        $this->assertEquals('Page 1', trim($elements[0]->getHtml()), 'Element for current page is not a link.');
        $next_page_link = $elements[1]->find('css', 'a');
        $this->assertNotEmpty($next_page_link, 'Link to next page found.');
        $this->assertEquals('Go to next page', $next_page_link->getAttribute('title'));
        // Navigate to next page.
        $this->clickPreviewLinkAJAX($next_page_link, 3);
        // Test that the pager is present and rendered.
        $elements = $this->xpath('//ul[contains(@class, "pager__items")]/li');
        $this->assertNotEmpty($elements);
        // Verify elements and links to pages.
        // We expect to find 3 elements: previous page with a link, current
        // page with no link, and next page with a link.
        $previous_page_link = $elements[0]->find('css', 'a');
        $this->assertNotEmpty($previous_page_link, 'Link to previous page found.');
        $this->assertEquals('Go to previous page', $previous_page_link->getAttribute('title'));
        $this->assertEquals('Page 2', trim($elements[1]->getHtml()), 'Element for current page is not a link.');
        $next_page_link = $elements[2]->find('css', 'a');
        $this->assertNotEmpty($next_page_link, 'Link to next page found.');
        $this->assertEquals('Go to next page', $next_page_link->getAttribute('title'));
    }
    
    /**
     * Tests the link to sort in the preview form.
     */
    public function testPreviewSortLink() {
        // Get the preview.
        $this->getPreviewAJAX('test_click_sort_ajax', 'page_1', 0);
        // Test that the header label is present.
        $element = $this->assertSession()
            ->elementExists('xpath', '//th[contains(@class, "views-field views-field-name")]/a');
        // Verify link.
        $this->assertSession()
            ->linkByHrefExists('preview/page_1?_wrapper_format=drupal_ajax&order=name&sort=desc', 0, 'The output URL is as expected.');
        // Click link to sort.
        $element->click();
        $sort_link = $this->assertSession()
            ->waitForElement('xpath', '//th[contains(@class, \'views-field views-field-name is-active\')]/a');
        $this->assertNotEmpty($sort_link);
        // Verify link.
        $this->assertSession()
            ->linkByHrefExists('preview/page_1?_wrapper_format=drupal_ajax&order=name&sort=asc', 0, 'The output URL is as expected.');
    }
    
    /**
     * Get the preview form and force an AJAX preview update.
     *
     * @param string $view_name
     *   The view to test.
     * @param string $panel_id
     *   The view panel to test.
     * @param int $row_count
     *   The expected number of rows in the preview.
     */
    protected function getPreviewAJAX($view_name, $panel_id, $row_count) {
        $this->drupalGet('admin/structure/views/view/' . $view_name . '/edit/' . $panel_id);
        $this->getSession()
            ->getPage()
            ->pressButton('Update preview');
        $this->assertSession()
            ->assertWaitOnAjaxRequest();
        $this->assertPreviewAJAX($row_count);
    }
    
    /**
     * Click on a preview link.
     *
     * @param \Behat\Mink\Element\NodeElement $element
     *   The element to click.
     * @param int $row_count
     *   The expected number of rows in the preview.
     */
    protected function clickPreviewLinkAJAX(NodeElement $element, $row_count) {
        $element->click();
        $this->assertSession()
            ->assertWaitOnAjaxRequest();
        $this->assertPreviewAJAX($row_count);
    }
    
    /**
     * Assert that the preview contains expected data.
     *
     * @param int $row_count
     *   The expected number of rows in the preview.
     *
     * @internal
     */
    protected function assertPreviewAJAX(int $row_count) : void {
        $elements = $this->getSession()
            ->getPage()
            ->findAll('css', '#views-live-preview .views-row');
        $this->assertCount($row_count, $elements, 'Expected items found on page.');
    }
    
    /**
     * Asserts that an element has a given class.
     *
     * @param \Behat\Mink\Element\NodeElement $element
     *   The element to test.
     * @param string $class
     *   The class to assert.
     * @param string $message
     *   (optional) A verbose message to output.
     *
     * @internal
     */
    protected function assertClass(NodeElement $element, string $class, string $message = '') : void {
        if (!isset($message)) {
            $message = "Class .{$class} found.";
        }
        $this->assertStringContainsString($class, $element->getAttribute('class'), $message);
    }

}