<?php
/**
* Did You Mean feature.
*
* @since 4.6.0
* @package elasticpress
*/
namespace ElasticPress\Feature\DidYouMean;
use ElasticPress\{Elasticsearch, Feature, FeatureRequirementsStatus, Features };
/**
* Did You Mean feature class.
*/
class DidYouMean extends Feature {
/**
* Initialize feature, setting it's config.
*/
public function __construct() {
$this->slug = 'did-you-mean';
$this->title = esc_html__( 'Did You Mean', 'elasticpress' );
$this->summary = '<p>' . __( '"Did You Mean" search feature provides alternative suggestions for misspelled or ambiguous search queries, enhancing search accuracy and user experience. To display suggestions in your theme, please follow <a href="https://elasticpress.zendesk.com/hc/en-us/articles/16673223107085-Did-You-Mean">this tutorial</a>.', 'elasticpress' ) . '</p>';
$this->docs_url = __( 'https://elasticpress.zendesk.com/hc/en-us/articles/16673223107085-Did-You-Mean', 'elasticpress' );
$this->requires_install_reindex = true;
$this->available_during_installation = true;
$this->default_settings = [
'search_behavior' => '0',
];
$this->requires_feature = 'search';
parent::__construct();
}
/**
* Setup search functionality.
*
* @return void
*/
public function setup() {
add_filter( 'ep_post_mapping', [ $this, 'add_mapping' ] );
add_filter( 'ep_post_formatted_args', [ $this, 'add_query_args' ], 10, 3 );
add_filter( 'ep_integrate_search_queries', [ $this, 'set_ep_suggestion' ], 10, 2 );
add_action( 'template_redirect', [ $this, 'automatically_redirect_user' ] );
add_action( 'ep_suggestions', [ $this, 'the_output' ] );
}
/**
* Output feature box long.
*
* @return void
*/
public function output_feature_box_long() {
?>
<p>
<?php
echo wp_kses_post(
sprintf(
/* translators: Tutorial URL */
__( '"Did You Mean" search feature provides alternative suggestions for misspelled or ambiguous search queries, enhancing search accuracy and user experience. To display suggestions in your theme, please follow <a href="%s">this tutorial</a>.', 'elasticpress' ),
'https://elasticpress.zendesk.com/hc/en-us/articles/16673223107085-Did-You-Mean'
)
);
?>
</p>
<?php
}
/**
* Add mapping.
*
* @param array $mapping Post mapping.
*/
public function add_mapping( $mapping ) : array {
// Shingle token filter.
$mapping['settings']['analysis']['filter']['shingle_filter'] = [
'type' => 'shingle',
'min_shingle_size' => 2,
'max_shingle_size' => 3,
];
// Custom analyzer.
$mapping['settings']['analysis']['analyzer']['trigram'] = [
'type' => 'custom',
'tokenizer' => 'standard',
'filter' => [
'lowercase',
'shingle_filter',
],
];
if ( version_compare( (string) Elasticsearch::factory()->get_elasticsearch_version(), '7.0', '<' ) ) {
$mapping['mappings']['post']['properties']['post_content']['fields'] = [
'shingle' => [
'type' => 'text',
'analyzer' => 'trigram',
],
];
} else {
$mapping['mappings']['properties']['post_content']['fields'] = [
'shingle' => [
'type' => 'text',
'analyzer' => 'trigram',
],
];
}
return $mapping;
}
/**
* Return the suggested search term.
*
* @param WP_Query $query WP_Query object
* @return string|false
*/
public function get_suggestion( $query = null ) {
global $wp_query;
$settings = $this->get_settings();
if ( empty( $settings['active'] ) ) {
return false;
}
if ( ! $query && $wp_query->is_main_query() && $wp_query->is_search() ) {
$query = $wp_query;
}
if ( ! is_a( $query, '\WP_Query' ) ) {
return false;
}
$term = $this->get_suggested_term( $query );
if ( empty( $term ) ) {
return false;
}
$html = sprintf( '<span class="ep-spell-suggestion">%s: <a href="%s">%s</a>?</span>', esc_html__( 'Did you mean', 'elasticpress' ), get_search_link( $term ), $term );
$html .= $this->get_alternatives_terms( $query );
$terms = $query->suggested_terms['options'] ?? [];
/**
* Filter the did you mean suggested HTML.
*
* @since 4.6.0
* @hook ep_suggestion_html
* @param {string} $html The HTML output.
* @param {array} $terms All suggested terms.
* @param {WP_Query} $query The WP_Query object.
* @return {string} New HTML output
*/
return apply_filters( 'ep_suggestion_html', $html, $terms, $query );
}
/**
* If needed set the `suggest` to ES query clause.
*
* @param array $formatted_args Formatted Elasticsearch query.
* @param array $args WP_Query arguments
* @param array $wp_query WP_Query object
*/
public function add_query_args( $formatted_args, $args, $wp_query ) : array {
$search_analyzer = [
'phrase' => [
'field' => 'post_content.shingle',
'max_errors' => 2,
'direct_generator' => [
[
'field' => 'post_content.shingle',
],
],
],
];
/**
* Filter the search analyzer use for the did you mean feature.
*
* @since 4.6.0
* @hook ep_search_suggestion_analyzer
* @param {array} $search_analyzer Search analyzer
* @param {array} $formatted_args Formatted Elasticsearch query
* @param {array} $args WP_Query arguments
* @param {WP_Query} $wp_query WP_Query object
* @return {array} New search analyzer
*/
$search_analyzer = apply_filters( 'ep_search_suggestion_analyzer', $search_analyzer, $formatted_args, $args, $wp_query );
if ( ! empty( $args['s'] ) ) {
$formatted_args['suggest'] = array(
'text' => $args['s'],
'ep_suggestion' => $search_analyzer,
);
}
return $formatted_args;
}
/**
* Set the ep_suggestion flag to true if the query is a search query.
*
* @param bool $enabled Whether to enable the search queries integration.
* @param WP_Query $query The WP_Query object.
*/
public function set_ep_suggestion( $enabled, $query ) : bool {
if ( $query->is_search() && ! empty( $query->query_vars['s'] ) ) {
$query->set( 'ep_suggestion', true );
}
return $enabled;
}
/**
* Returns requirements status of feature
*
* Requires the search feature to be activated
*/
public function requirements_status() : FeatureRequirementsStatus {
return new FeatureRequirementsStatus( 1 );
}
/**
* Display feature settings.
*
* @return void
*/
public function output_feature_box_settings() {
$settings = $this->get_settings();
?>
<div class="field">
<div class="field-name status"><?php esc_html_e( 'Search behavior when no result is found', 'elasticpress' ); ?></div>
<div class="input-wrap">
<label><input name="settings[search_behavior]" type="radio" <?php checked( ! (bool) $settings['search_behavior'] ); ?> value="0"><?php esc_html_e( 'Display the top suggestion', 'elasticpress' ); ?></label><br>
<label><input name="settings[search_behavior]" type="radio" <?php checked( $settings['search_behavior'], 'list' ); ?> value="list"><?php esc_html_e( 'Display all the suggestions', 'elasticpress' ); ?></label><br>
<label><input name="settings[search_behavior]" type="radio" <?php checked( $settings['search_behavior'], 'redirect' ); ?> value="redirect"><?php esc_html_e( 'Automatically redirect the user to the top suggestion', 'elasticpress' ); ?></label><br>
</div>
</div>
<?php
}
/**
* Returns the list of other suggestions
*
* @param WP_Query $query WP_Query object
* @return string|false
*/
protected function get_alternatives_terms( $query ) {
global $wp_query;
if ( ! $query && $wp_query->is_main_query() && $wp_query->is_search() ) {
$query = $wp_query;
}
if ( ! is_a( $query, '\WP_Query' ) ) {
return false;
}
$settings = $this->get_settings();
// If there are posts, we don't need to show the list of suggestions.
if ( 'list' !== $settings['search_behavior'] || $query->found_posts ) {
return false;
}
$options = $query->suggested_terms['options'] ?? [];
array_shift( $options );
if ( empty( $options ) ) {
return '';
}
$html = '<div class="ep-spell-suggestions">';
$html .= esc_html__( 'Other suggestions:', 'elasticpress' );
$html .= '<ul class="ep-suggestions-list">';
foreach ( $options as $option ) {
$html .= sprintf( '<li><a href="%s">%s</a></li>', get_search_link( $option['text'] ), $option['text'] );
}
$html .= '</ul>';
$html .= '</div>';
return $html;
}
/**
* Returns the top suggested term
*
* @param WP_Query $query WP_Query object
* @return string|bool
*/
public function get_suggested_term( $query ) {
$options = $query->suggested_terms['options'] ?? [];
return ! empty( $options ) ? $options[0]['text'] : false;
}
/**
* Redirect user to suggested search term if no results found and search_behavior is set to redirect.
*
* @return void
*/
public function automatically_redirect_user() {
global $wp_query;
if ( ! $wp_query->is_main_query() || ! $wp_query->is_search() ) {
return;
}
if ( $wp_query->found_posts ) {
return;
}
$settings = $this->get_settings();
if ( 'redirect' !== $settings['search_behavior'] ) {
return;
}
$term = $this->get_suggested_term( $wp_query );
if ( empty( $term ) ) {
return;
}
$url = get_search_link( $term );
$url = add_query_arg(
[
'ep_suggestion_original_term' => $wp_query->query_vars['s'],
],
$url
);
wp_safe_redirect( $url );
exit;
}
/**
* Return a message to the user when the original search term has no results and the user is redirected to the suggested term.
*
* @param WP_Query $query WP_Query object
*
* @return string|void
*/
public function get_original_search_term( $query = null ) {
global $wp_query;
$settings = $this->get_settings();
if ( empty( $settings['active'] ) ) {
return false;
}
if ( ! $query && $wp_query->is_main_query() && $wp_query->is_search() ) {
$query = $wp_query;
}
if ( ! is_a( $query, '\WP_Query' ) ) {
return;
}
if ( ! isset( $_GET['ep_suggestion_original_term'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended
return;
}
$settings = $this->get_settings();
if ( 'redirect' !== $settings['search_behavior'] ) {
return;
}
$original_term = sanitize_text_field( wp_unslash( $_GET['ep_suggestion_original_term'] ) ); // phpcs:ignore WordPress.Security.NonceVerification.Recommended
$html = sprintf(
'<div class="ep-original-search-term-message">
<span class="result">%s</span><strong>%s</strong>
<br/>
<span class="no-result">%s</span><strong>%s</strong>
</div>',
esc_html__( 'Showing results for: ', 'elasticpress' ),
esc_html( $query->query_vars['s'] ),
esc_html__( 'No results for: ', 'elasticpress' ),
esc_html( $original_term )
);
/**
* Filter the HTML output for the original search term.
*
* @since 4.6.0
* @hook ep_suggestion_original_search_term_html
* @param {string} $html HTML output
* @param {string} $search_term Suggested search term
* @param {string} $original_term Original search term
* @param {WP_Query} $query WP_Query object
* @return {string} New HTML output
*/
return apply_filters( 'ep_suggestion_original_search_term_html', $html, $query->query_vars['s'], $original_term, $query );
}
/**
* Returns the suggestion
*
* @param WP_Query $query WP_Query object
* @return void
*/
public function the_output( $query = null ) {
$html = $this->get_original_search_term( $query );
$html .= $this->get_suggestion( $query );
echo wp_kses_post( $html );
}
/**
* Set the `settings_schema` attribute
*
* @since 5.0.0
*/
protected function set_settings_schema() {
$this->settings_schema = [
[
'default' => '0',
'key' => 'search_behavior',
'label' => __( 'Search behavior when no result is found', 'elasticpress' ),
'options' => [
[
'label' => __( 'Display the top suggestion', 'elasticpress' ),
'value' => '0',
],
[
'label' => __( 'Display all the suggestions', 'elasticpress' ),
'value' => 'list',
],
[
'label' => __( 'Automatically redirect the user to the top suggestion', 'elasticpress' ),
'value' => 'redirect',
],
],
'type' => 'radio',
],
];
}
}