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wp-includes/class-wp-date-query.php

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<?php
/**
 * Class for generating SQL clauses that filter a primary query according to date.
 *
 * WP_Date_Query is a helper that allows primary query classes, such as WP_Query, to filter
 * their results by date columns, by generating `WHERE` subclauses to be attached to the
 * primary SQL query string.
 *
 * Attempting to filter by an invalid date value (eg month=13) will generate SQL that will
 * return no results. In these cases, a _doing_it_wrong() error notice is also thrown.
 * See WP_Date_Query::validate_date_values().
 *
 * @link https://developer.wordpress.org/reference/classes/wp_query/
 *
 * @since 3.7.0
 */
#[AllowDynamicProperties]
class WP_Date_Query {
    /**
     * Array of date queries.
     *
     * See WP_Date_Query::__construct() for information on date query arguments.
     *
     * @since 3.7.0
     * @var array
     */
    public $queries = array();

    /**
     * The default relation between top-level queries. Can be either 'AND' or 'OR'.
     *
     * @since 3.7.0
     * @var string
     */
    public $relation = 'AND';

    /**
     * The column to query against. Can be changed via the query arguments.
     *
     * @since 3.7.0
     * @var string
     */
    public $column = 'post_date';

    /**
     * The value comparison operator. Can be changed via the query arguments.
     *
     * @since 3.7.0
     * @var string
     */
    public $compare = '=';

    /**
     * Supported time-related parameter keys.
     *
     * @since 4.1.0
     * @var string[]
     */
    public $time_keys = array( 'after', 'before', 'year', 'month', 'monthnum', 'week', 'w', 'dayofyear', 'day', 'dayofweek', 'dayofweek_iso', 'hour', 'minute', 'second' );

    /**
     * Constructor.
     *
     * Time-related parameters that normally require integer values ('year', 'month', 'week', 'dayofyear', 'day',
     * 'dayofweek', 'dayofweek_iso', 'hour', 'minute', 'second') accept arrays of integers for some values of
     * 'compare'. When 'compare' is 'IN' or 'NOT IN', arrays are accepted; when 'compare' is 'BETWEEN' or 'NOT
     * BETWEEN', arrays of two valid values are required. See individual argument descriptions for accepted values.
     *
     * @since 3.7.0
     * @since 4.0.0 The $inclusive logic was updated to include all times within the date range.
     * @since 4.1.0 Introduced 'dayofweek_iso' time type parameter.
     *
     * @param array  $date_query {
     *     Array of date query clauses.
     *
     *     @type array ...$0 {
     *         @type string $column   Optional. The column to query against. If undefined, inherits the value of
     *                                the `$default_column` parameter. See WP_Date_Query::validate_column() and
     *                                the {@see 'date_query_valid_columns'} filter for the list of accepted values.
     *                                Default 'post_date'.
     *         @type string $compare  Optional. The comparison operator. Accepts '=', '!=', '>', '>=', '<', '<=',
     *                                'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN'. Default '='.
     *         @type string $relation Optional. The boolean relationship between the date queries. Accepts 'OR' or 'AND'.
     *                                Default 'OR'.
     *         @type array  ...$0 {
     *             Optional. An array of first-order clause parameters, or another fully-formed date query.
     *
     *             @type string|array $before {
     *                 Optional. Date to retrieve posts before. Accepts `strtotime()`-compatible string,
     *                 or array of 'year', 'month', 'day' values.
     *
     *                 @type string $year  The four-digit year. Default empty. Accepts any four-digit year.
     *                 @type string $month Optional when passing array.The month of the year.
     *                                     Default (string:empty)|(array:1). Accepts numbers 1-12.
     *                 @type string $day   Optional when passing array.The day of the month.
     *                                     Default (string:empty)|(array:1). Accepts numbers 1-31.
     *             }
     *             @type string|array $after {
     *                 Optional. Date to retrieve posts after. Accepts `strtotime()`-compatible string,
     *                 or array of 'year', 'month', 'day' values.
     *
     *                 @type string $year  The four-digit year. Accepts any four-digit year. Default empty.
     *                 @type string $month Optional when passing array. The month of the year. Accepts numbers 1-12.
     *                                     Default (string:empty)|(array:12).
     *                 @type string $day   Optional when passing array.The day of the month. Accepts numbers 1-31.
     *                                     Default (string:empty)|(array:last day of month).
     *             }
     *             @type string       $column        Optional. Used to add a clause comparing a column other than
     *                                               the column specified in the top-level `$column` parameter.
     *                                               See WP_Date_Query::validate_column() and
     *                                               the {@see 'date_query_valid_columns'} filter for the list
     *                                               of accepted values. Default is the value of top-level `$column`.
     *             @type string       $compare       Optional. The comparison operator. Accepts '=', '!=', '>', '>=',
     *                                               '<', '<=', 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN'. 'IN',
     *                                               'NOT IN', 'BETWEEN', and 'NOT BETWEEN'. Comparisons support
     *                                               arrays in some time-related parameters. Default '='.
     *             @type bool         $inclusive     Optional. Include results from dates specified in 'before' or
     *                                               'after'. Default false.
     *             @type int|int[]    $year          Optional. The four-digit year number. Accepts any four-digit year
     *                                               or an array of years if `$compare` supports it. Default empty.
     *             @type int|int[]    $month         Optional. The two-digit month number. Accepts numbers 1-12 or an
     *                                               array of valid numbers if `$compare` supports it. Default empty.
     *             @type int|int[]    $week          Optional. The week number of the year. Accepts numbers 0-53 or an
     *                                               array of valid numbers if `$compare` supports it. Default empty.
     *             @type int|int[]    $dayofyear     Optional. The day number of the year. Accepts numbers 1-366 or an
     *                                               array of valid numbers if `$compare` supports it.
     *             @type int|int[]    $day           Optional. The day of the month. Accepts numbers 1-31 or an array
     *                                               of valid numbers if `$compare` supports it. Default empty.
     *             @type int|int[]    $dayofweek     Optional. The day number of the week. Accepts numbers 1-7 (1 is
     *                                               Sunday) or an array of valid numbers if `$compare` supports it.
     *                                               Default empty.
     *             @type int|int[]    $dayofweek_iso Optional. The day number of the week (ISO). Accepts numbers 1-7
     *                                               (1 is Monday) or an array of valid numbers if `$compare` supports it.
     *                                               Default empty.
     *             @type int|int[]    $hour          Optional. The hour of the day. Accepts numbers 0-23 or an array
     *                                               of valid numbers if `$compare` supports it. Default empty.
     *             @type int|int[]    $minute        Optional. The minute of the hour. Accepts numbers 0-59 or an array
     *                                               of valid numbers if `$compare` supports it. Default empty.
     *             @type int|int[]    $second        Optional. The second of the minute. Accepts numbers 0-59 or an
     *                                               array of valid numbers if `$compare` supports it. Default empty.
     *         }
     *     }
     * }
     * @param string $default_column Optional. Default column to query against. See WP_Date_Query::validate_column()
     *                               and the {@see 'date_query_valid_columns'} filter for the list of accepted values.
     *                               Default 'post_date'.
     */
    public function __construct( $date_query, $default_column = 'post_date' ) {
        if ( empty( $date_query ) || ! is_array( $date_query ) ) {
            return;
        }

        if ( isset( $date_query['relation'] ) ) {
            $this->relation = $this->sanitize_relation( $date_query['relation'] );
        } else {
            $this->relation = 'AND';
        }

        // Support for passing time-based keys in the top level of the $date_query array.
        if ( ! isset( $date_query[0] ) ) {
            $date_query = array( $date_query );
        }

        if ( ! empty( $date_query['column'] ) ) {
            $date_query['column'] = esc_sql( $date_query['column'] );
        } else {
            $date_query['column'] = esc_sql( $default_column );
        }

        $this->column = $this->validate_column( $this->column );

        $this->compare = $this->get_compare( $date_query );

        $this->queries = $this->sanitize_query( $date_query );
    }

    /**
     * Recursive-friendly query sanitizer.
     *
     * Ensures that each query-level clause has a 'relation' key, and that
     * each first-order clause contains all the necessary keys from `$defaults`.
     *
     * @since 4.1.0
     *
     * @param array $queries
     * @param array $parent_query
     * @return array Sanitized queries.
     */
    public function sanitize_query( $queries, $parent_query = null ) {
        $cleaned_query = array();

        $defaults = array(
            'column'   => 'post_date',
            'compare'  => '=',
            'relation' => 'AND',
        );

        // Numeric keys should always have array values.
        foreach ( $queries as $qkey => $qvalue ) {
            if ( is_numeric( $qkey ) && ! is_array( $qvalue ) ) {
                unset( $queries[ $qkey ] );
            }
        }

        // Each query should have a value for each default key. Inherit from the parent when possible.
        foreach ( $defaults as $dkey => $dvalue ) {
            if ( isset( $queries[ $dkey ] ) ) {
                continue;
            }

            if ( isset( $parent_query[ $dkey ] ) ) {
                $queries[ $dkey ] = $parent_query[ $dkey ];
            } else {
                $queries[ $dkey ] = $dvalue;
            }
        }

        // Validate the dates passed in the query.
        if ( $this->is_first_order_clause( $queries ) ) {
            $this->validate_date_values( $queries );
        }

        // Sanitize the relation parameter.
        $queries['relation'] = $this->sanitize_relation( $queries['relation'] );

        foreach ( $queries as $key => $q ) {
            if ( ! is_array( $q ) || in_array( $key, $this->time_keys, true ) ) {
                // This is a first-order query. Trust the values and sanitize when building SQL.
                $cleaned_query[ $key ] = $q;
            } else {
                // Any array without a time key is another query, so we recurse.
                $cleaned_query[] = $this->sanitize_query( $q, $queries );
            }
        }

        return $cleaned_query;
    }

    /**
     * Determines whether this is a first-order clause.
     *
     * Checks to see if the current clause has any time-related keys.
     * If so, it's first-order.
     *
     * @since 4.1.0
     *
     * @param array $query Query clause.
     * @return bool True if this is a first-order clause.
     */
    protected function is_first_order_clause( $query ) {
        $time_keys = array_intersect( $this->time_keys, array_keys( $query ) );
        return ! empty( $time_keys );
    }

    /**
     * Determines and validates what comparison operator to use.
     *
     * @since 3.7.0
     *
     * @param array $query A date query or a date subquery.
     * @return string The comparison operator.
     */
    public function get_compare( $query ) {
        if ( ! empty( $query['compare'] )
            && in_array( $query['compare'], array( '=', '!=', '>', '>=', '<', '<=', 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN' ), true )
        ) {
            return strtoupper( $query['compare'] );
        }

        return $this->compare;
    }

    /**
     * Validates the given date_query values and triggers errors if something is not valid.
     *
     * Note that date queries with invalid date ranges are allowed to
     * continue (though of course no items will be found for impossible dates).
     * This method only generates debug notices for these cases.
     *
     * @since 4.1.0
     *
     * @param array $date_query The date_query array.
     * @return bool True if all values in the query are valid, false if one or more fail.
     */
    public function validate_date_values( $date_query = array() ) {
        if ( empty( $date_query ) ) {
            return false;
        }

        $valid = true;

        /*
         * Validate 'before' and 'after' up front, then let the
         * validation routine continue to be sure that all invalid
         * values generate errors too.
         */
        if ( array_key_exists( 'before', $date_query ) && is_array( $date_query['before'] ) ) {
            $valid = $this->validate_date_values( $date_query['before'] );
        }

        if ( array_key_exists( 'after', $date_query ) && is_array( $date_query['after'] ) ) {
            $valid = $this->validate_date_values( $date_query['after'] );
        }

        // Array containing all min-max checks.
        $min_max_checks = array();

        // Days per year.
        if ( array_key_exists( 'year', $date_query ) ) {
            /*
             * If a year exists in the date query, we can use it to get the days.
             * If multiple years are provided (as in a BETWEEN), use the first one.
             */
            if ( is_array( $date_query['year'] ) ) {
                $_year = reset( $date_query['year'] );
            } else {
                $_year = $date_query['year'];
            }

            $max_days_of_year = gmdate( 'z', mktime( 0, 0, 0, 12, 31, $_year ) ) + 1;
        } else {
            // Otherwise we use the max of 366 (leap-year).
            $max_days_of_year = 366;
        }

        $min_max_checks['dayofyear'] = array(
            'min' => 1,
            'max' => $max_days_of_year,
        );

        // Days per week.
        $min_max_checks['dayofweek'] = array(
            'min' => 1,
            'max' => 7,
        );

        // Days per week.
        $min_max_checks['dayofweek_iso'] = array(
            'min' => 1,
            'max' => 7,
        );

        // Months per year.
        $min_max_checks['month'] = array(
            'min' => 1,
            'max' => 12,
        );

        // Weeks per year.
        if ( isset( $_year ) ) {
            /*
             * If we have a specific year, use it to calculate number of weeks.
             * Note: the number of weeks in a year is the date in which Dec 28 appears.
             */
            $week_count = gmdate( 'W', mktime( 0, 0, 0, 12, 28, $_year ) );

        } else {
            // Otherwise set the week-count to a maximum of 53.
            $week_count = 53;
        }

        $min_max_checks['week'] = array(
            'min' => 1,
            'max' => $week_count,
        );

        // Days per month.
        $min_max_checks['day'] = array(
            'min' => 1,
            'max' => 31,
        );

        // Hours per day.
        $min_max_checks['hour'] = array(
            'min' => 0,
            'max' => 23,
        );

        // Minutes per hour.
        $min_max_checks['minute'] = array(
            'min' => 0,
            'max' => 59,
        );

        // Seconds per minute.
        $min_max_checks['second'] = array(
            'min' => 0,
            'max' => 59,
        );

        // Concatenate and throw a notice for each invalid value.
        foreach ( $min_max_checks as $key => $check ) {
            if ( ! array_key_exists( $key, $date_query ) ) {
                continue;
            }

            // Throw a notice for each failing value.
            foreach ( (array) $date_query[ $key ] as $_value ) {
                $is_between = $_value >= $check['min'] && $_value <= $check['max'];

                if ( ! is_numeric( $_value ) || ! $is_between ) {
                    $error = sprintf(
                        /* translators: Date query invalid date message. 1: Invalid value, 2: Type of value, 3: Minimum valid value, 4: Maximum valid value. */
                        __( 'Invalid value %1$s for %2$s. Expected value should be between %3$s and %4$s.' ),
                        '<code>' . esc_html( $_value ) . '</code>',
                        '<code>' . esc_html( $key ) . '</code>',
                        '<code>' . esc_html( $check['min'] ) . '</code>',
                        '<code>' . esc_html( $check['max'] ) . '</code>'
                    );

                    _doing_it_wrong( __CLASS__, $error, '4.1.0' );

                    $valid = false;
                }
            }
        }

        // If we already have invalid date messages, don't bother running through checkdate().
        if ( ! $valid ) {
            return $valid;
        }

        $day_month_year_error_msg = '';

        $day_exists   = array_key_exists( 'day', $date_query ) && is_numeric( $date_query['day'] );
        $month_exists = array_key_exists( 'month', $date_query ) && is_numeric( $date_query['month'] );
        $year_exists  = array_key_exists( 'year', $date_query ) && is_numeric( $date_query['year'] );

        if ( $day_exists && $month_exists && $year_exists ) {
            // 1. Checking day, month, year combination.
            if ( ! wp_checkdate( $date_query['month'], $date_query['day'], $date_query['year'], sprintf( '%s-%s-%s', $date_query['year'], $date_query['month'], $date_query['day'] ) ) ) {
                $day_month_year_error_msg = sprintf(
                    /* translators: 1: Year, 2: Month, 3: Day of month. */
                    __( 'The following values do not describe a valid date: year %1$s, month %2$s, day %3$s.' ),
                    '<code>' . esc_html( $date_query['year'] ) . '</code>',
                    '<code>' . esc_html( $date_query['month'] ) . '</code>',
                    '<code>' . esc_html( $date_query['day'] ) . '</code>'
                );

                $valid = false;
            }
        } elseif ( $day_exists && $month_exists ) {
            /*
             * 2. checking day, month combination
             * We use 2012 because, as a leap year, it's the most permissive.
             */
            if ( ! wp_checkdate( $date_query['month'], $date_query['day'], 2012, sprintf( '2012-%s-%s', $date_query['month'], $date_query['day'] ) ) ) {
                $day_month_year_error_msg = sprintf(
                    /* translators: 1: Month, 2: Day of month. */
                    __( 'The following values do not describe a valid date: month %1$s, day %2$s.' ),
                    '<code>' . esc_html( $date_query['month'] ) . '</code>',
                    '<code>' . esc_html( $date_query['day'] ) . '</code>'
                );

                $valid = false;
            }
        }

        if ( ! empty( $day_month_year_error_msg ) ) {
            _doing_it_wrong( __CLASS__, $day_month_year_error_msg, '4.1.0' );
        }

        return $valid;
    }

    /**
     * Validates a column name parameter.
     *
     * Column names without a table prefix (like 'post_date') are checked against a list of
     * allowed and known tables, and then, if found, have a table prefix (such as 'wp_posts.')
     * prepended. Prefixed column names (such as 'wp_posts.post_date') bypass this allowed
     * check, and are only sanitized to remove illegal characters.
     *
     * @since 3.7.0
     *
     * @global wpdb $wpdb WordPress database abstraction object.
     *
     * @param string $column The user-supplied column name.
     * @return string A validated column name value.
     */
    public function validate_column( $column ) {
        global $wpdb;

        $valid_columns = array(
            'post_date',
            'post_date_gmt',
            'post_modified',
            'post_modified_gmt',
            'comment_date',
            'comment_date_gmt',
            'user_registered',
            'registered',
            'last_updated',
        );

        // Attempt to detect a table prefix.
        if ( ! str_contains( $column, '.' ) ) {
            /**
             * Filters the list of valid date query columns.
             *
             * @since 3.7.0
             * @since 4.1.0 Added 'user_registered' to the default recognized columns.
             * @since 4.6.0 Added 'registered' and 'last_updated' to the default recognized columns.
             *
             * @param string[] $valid_columns An array of valid date query columns. Defaults
             *                                are 'post_date', 'post_date_gmt', 'post_modified',
             *                                'post_modified_gmt', 'comment_date', 'comment_date_gmt',
             *                                'user_registered', 'registered', 'last_updated'.
             */
            if ( ! in_array( $column, apply_filters( 'date_query_valid_columns', $valid_columns ), true ) ) {
                $column = 'post_date';
            }

            $known_columns = array(
                $wpdb->posts    => array(
                    'post_date',
                    'post_date_gmt',
                    'post_modified',
                    'post_modified_gmt',
                ),
                $wpdb->comments => array(
                    'comment_date',
                    'comment_date_gmt',
                ),
                $wpdb->users    => array(
                    'user_registered',
                ),
                $wpdb->blogs    => array(
                    'registered',
                    'last_updated',
                ),
            );

            // If it's a known column name, add the appropriate table prefix.
            foreach ( $known_columns as $table_name => $table_columns ) {
                if ( in_array( $column, $table_columns, true ) ) {
                    $column = $table_name . '.' . $column;
                    break;
                }
            }
        }

        // Remove unsafe characters.
        return preg_replace( '/[^a-zA-Z0-9_$\.]/', '', $column );
    }

    /**
     * Generates WHERE clause to be appended to a main query.
     *
     * @since 3.7.0
     *
     * @return string MySQL WHERE clause.
     */
    public function get_sql() {
        $sql = $this->get_sql_clauses();

        $where = $sql['where'];

        /**
         * Filters the date query WHERE clause.
         *
         * @since 3.7.0
         *
         * @param string        $where WHERE clause of the date query.
         * @param WP_Date_Query $query The WP_Date_Query instance.
         */
        return apply_filters( 'get_date_sql', $where, $this );
    }

    /**
     * Generates SQL clauses to be appended to a main query.
     *
     * Called by the public WP_Date_Query::get_sql(), this method is abstracted
     * out to maintain parity with the other Query classes.
     *
     * @since 4.1.0
     *
     * @return string[] {
     *     Array containing JOIN and WHERE SQL clauses to append to the main query.
     *
     *     @type string $join  SQL fragment to append to the main JOIN clause.
     *     @type string $where SQL fragment to append to the main WHERE clause.
     * }
     */
    protected function get_sql_clauses() {
        $sql = $this->get_sql_for_query( $this->queries );

        if ( ! empty( $sql['where'] ) ) {
            $sql['where'] = ' AND ' . $sql['where'];
        }

        return $sql;
    }

    /**
     * Generates SQL clauses for a single query array.
     *
     * If nested subqueries are found, this method recurses the tree to
     * produce the properly nested SQL.
     *
     * @since 4.1.0
     *
     * @param array $query Query to parse.
     * @param int   $depth Optional. Number of tree levels deep we currently are.
     *                     Used to calculate indentation. Default 0.
     * @return array {
     *     Array containing JOIN and WHERE SQL clauses to append to a single query array.
     *
     *     @type string $join  SQL fragment to append to the main JOIN clause.
     *     @type string $where SQL fragment to append to the main WHERE clause.
     * }
     */
    protected function get_sql_for_query( $query, $depth = 0 ) {
        $sql_chunks = array(
            'join'  => array(),
            'where' => array(),
        );

        $sql = array(
            'join'  => '',
            'where' => '',
        );

        $indent = '';
        for ( $i = 0; $i < $depth; $i++ ) {
            $indent .= '  ';
        }

        foreach ( $query as $key => $clause ) {
            if ( 'relation' === $key ) {
                $relation = $query['relation'];
            } elseif ( is_array( $clause ) ) {

                // This is a first-order clause.
                if ( $this->is_first_order_clause( $clause ) ) {
                    $clause_sql = $this->get_sql_for_clause( $clause, $query );

                    $where_count = count( $clause_sql['where'] );
                    if ( ! $where_count ) {
                        $sql_chunks['where'][] = '';
                    } elseif ( 1 === $where_count ) {
                        $sql_chunks['where'][] = $clause_sql['where'][0];
                    } else {
                        $sql_chunks['where'][] = '( ' . implode( ' AND ', $clause_sql['where'] ) . ' )';
                    }

                    $sql_chunks['join'] = array_merge( $sql_chunks['join'], $clause_sql['join'] );
                    // This is a subquery, so we recurse.
                } else {
                    $clause_sql = $this->get_sql_for_query( $clause, $depth + 1 );

                    $sql_chunks['where'][] = $clause_sql['where'];
                    $sql_chunks['join'][]  = $clause_sql['join'];
                }
            }
        }

        // Filter to remove empties.
        $sql_chunks['join']  = array_filter( $sql_chunks['join'] );
        $sql_chunks['where'] = array_filter( $sql_chunks['where'] );

        if ( empty( $relation ) ) {
            $relation = 'AND';
        }

        // Filter duplicate JOIN clauses and combine into a single string.
        if ( ! empty( $sql_chunks['join'] ) ) {
            $sql['join'] = implode( ' ', array_unique( $sql_chunks['join'] ) );
        }

        // Generate a single WHERE clause with proper brackets and indentation.
        if ( ! empty( $sql_chunks['where'] ) ) {
            $sql['where'] = '( ' . "\n  " . $indent . implode( ' ' . "\n  " . $indent . $relation . ' ' . "\n  " . $indent, $sql_chunks['where'] ) . "\n" . $indent . ')';
        }

        return $sql;
    }

    /**
     * Turns a single date clause into pieces for a WHERE clause.
     *
     * A wrapper for get_sql_for_clause(), included here for backward
     * compatibility while retaining the naming convention across Query classes.
     *
     * @since 3.7.0
     *
     * @param array $query Date query arguments.
     * @return array {
     *     Array containing JOIN and WHERE SQL clauses to append to the main query.
     *
     *     @type string[] $join  Array of SQL fragments to append to the main JOIN clause.
     *     @type string[] $where Array of SQL fragments to append to the main WHERE clause.
     * }
     */
    protected function get_sql_for_subquery( $query ) {
        return $this->get_sql_for_clause( $query, '' );
    }

    /**
     * Turns a first-order date query into SQL for a WHERE clause.
     *
     * @since 4.1.0
     *
     * @global wpdb $wpdb WordPress database abstraction object.
     *
     * @param array $query        Date query clause.
     * @param array $parent_query Parent query of the current date query.
     * @return array {
     *     Array containing JOIN and WHERE SQL clauses to append to the main query.
     *
     *     @type string[] $join  Array of SQL fragments to append to the main JOIN clause.
     *     @type string[] $where Array of SQL fragments to append to the main WHERE clause.
     * }
     */
    protected function get_sql_for_clause( $query, $parent_query ) {
        global $wpdb;

        // The sub-parts of a $where part.
        $where_parts = array();

        $column = ( ! empty( $query['column'] ) ) ? esc_sql( $query['column'] ) : $this->column;

        $column = $this->validate_column( $column );

        $compare = $this->get_compare( $query );

        $inclusive = ! empty( $query['inclusive'] );

        // Assign greater- and less-than values.
        $lt = '<';
        $gt = '>';

        if ( $inclusive ) {
            $lt .= '=';
            $gt .= '=';
        }

        // Range queries.
        if ( ! empty( $query['after'] ) ) {
            $where_parts[] = $wpdb->prepare( "$column $gt %s", $this->build_mysql_datetime( $query['after'], ! $inclusive ) );
        }
        if ( ! empty( $query['before'] ) ) {
            $where_parts[] = $wpdb->prepare( "$column $lt %s", $this->build_mysql_datetime( $query['before'], $inclusive ) );
        }
        // Specific value queries.

        $date_units = array(
            'YEAR'           => array( 'year' ),
            'MONTH'          => array( 'month', 'monthnum' ),
            '_wp_mysql_week' => array( 'week', 'w' ),
            'DAYOFYEAR'      => array( 'dayofyear' ),
            'DAYOFMONTH'     => array( 'day' ),
            'DAYOFWEEK'      => array( 'dayofweek' ),
            'WEEKDAY'        => array( 'dayofweek_iso' ),
        );

        // Check of the possible date units and add them to the query.
        foreach ( $date_units as $sql_part => $query_parts ) {
            foreach ( $query_parts as $query_part ) {
                if ( isset( $query[ $query_part ] ) ) {
                    $value = $this->build_value( $compare, $query[ $query_part ] );
                    if ( $value ) {
                        switch ( $sql_part ) {
                            case '_wp_mysql_week':
                                $where_parts[] = _wp_mysql_week( $column ) . " $compare $value";
                                break;
                            case 'WEEKDAY':
                                $where_parts[] = "$sql_part( $column ) + 1 $compare $value";
                                break;
                            default:
                                $where_parts[] = "$sql_part( $column ) $compare $value";
                        }

                        break;
                    }
                }
            }
        }

        if ( isset( $query['hour'] ) || isset( $query['minute'] ) || isset( $query['second'] ) ) {
            // Avoid notices.
            foreach ( array( 'hour', 'minute', 'second' ) as $unit ) {
                if ( ! isset( $query[ $unit ] ) ) {
                    $query[ $unit ] = null;
                }
            }

            $time_query = $this->build_time_query( $column, $compare, $query['hour'], $query['minute'], $query['second'] );
            if ( $time_query ) {
                $where_parts[] = $time_query;
            }
        }

        /*
         * Return an array of 'join' and 'where' for compatibility
         * with other query classes.
         */
        return array(
            'where' => $where_parts,
            'join'  => array(),
        );
    }

    /**
     * Builds and validates a value string based on the comparison operator.
     *
     * @since 3.7.0
     *
     * @param string       $compare The compare operator to use.
     * @param string|array $value   The value.
     * @return string|false|int The value to be used in SQL or false on error.
     */
    public function build_value( $compare, $value ) {
        if ( ! isset( $value ) ) {
            return false;
        }

        switch ( $compare ) {
            case 'IN':
            case 'NOT IN':
                $value = (array) $value;

                // Remove non-numeric values.
                $value = array_filter( $value, 'is_numeric' );

                if ( empty( $value ) ) {
                    return false;
                }

                return '(' . implode( ',', array_map( 'intval', $value ) ) . ')';

            case 'BETWEEN':
            case 'NOT BETWEEN':
                if ( ! is_array( $value ) || 2 !== count( $value ) ) {
                    $value = array( $value, $value );
                } else {
                    $value = array_values( $value );
                }

                // If either value is non-numeric, bail.
                foreach ( $value as $v ) {
                    if ( ! is_numeric( $v ) ) {
                        return false;
                    }
                }

                $value = array_map( 'intval', $value );

                return $value[0] . ' AND ' . $value[1];

            default:
                if ( ! is_numeric( $value ) ) {
                    return false;
                }

                return (int) $value;
        }
    }

    /**
     * Builds a MySQL format date/time based on some query parameters.
     *
     * You can pass an array of values (year, month, etc.) with missing parameter values being defaulted to
     * either the maximum or minimum values (controlled by the $default_to parameter). Alternatively you can
     * pass a string that will be passed to date_create().
     *
     * @since 3.7.0
     *
     * @param string|array $datetime       An array of parameters or a strtotime() string.
     * @param bool         $default_to_max Whether to round up incomplete dates. Supported by values
     *                                     of $datetime that are arrays, or string values that are a
     *                                     subset of MySQL date format ('Y', 'Y-m', 'Y-m-d', 'Y-m-d H:i').
     *                                     Default: false.
     * @return string|false A MySQL format date/time or false on failure.
     */
    public function build_mysql_datetime( $datetime, $default_to_max = false ) {
        if ( ! is_array( $datetime ) ) {

            /*
             * Try to parse some common date formats, so we can detect
             * the level of precision and support the 'inclusive' parameter.
             */
            if ( preg_match( '/^(\d{4})$/', $datetime, $matches ) ) {
                // Y
                $datetime = array(
                    'year' => (int) $matches[1],
                );

            } elseif ( preg_match( '/^(\d{4})\-(\d{2})$/', $datetime, $matches ) ) {
                // Y-m
                $datetime = array(
                    'year'  => (int) $matches[1],
                    'month' => (int) $matches[2],
                );

            } elseif ( preg_match( '/^(\d{4})\-(\d{2})\-(\d{2})$/', $datetime, $matches ) ) {
                // Y-m-d
                $datetime = array(
                    'year'  => (int) $matches[1],
                    'month' => (int) $matches[2],
                    'day'   => (int) $matches[3],
                );

            } elseif ( preg_match( '/^(\d{4})\-(\d{2})\-(\d{2}) (\d{2}):(\d{2})$/', $datetime, $matches ) ) {
                // Y-m-d H:i
                $datetime = array(
                    'year'   => (int) $matches[1],
                    'month'  => (int) $matches[2],
                    'day'    => (int) $matches[3],
                    'hour'   => (int) $matches[4],
                    'minute' => (int) $matches[5],
                );
            }

            // If no match is found, we don't support default_to_max.
            if ( ! is_array( $datetime ) ) {
                $wp_timezone = wp_timezone();

                // Assume local timezone if not provided.
                $dt = date_create( $datetime, $wp_timezone );

                if ( false === $dt ) {
                    return gmdate( 'Y-m-d H:i:s', false );
                }

                return $dt->setTimezone( $wp_timezone )->format( 'Y-m-d H:i:s' );
            }
        }

        $datetime = array_map( 'absint', $datetime );

        if ( ! isset( $datetime['year'] ) ) {
            $datetime['year'] = current_time( 'Y' );
        }

        if ( ! isset( $datetime['month'] ) ) {
            $datetime['month'] = ( $default_to_max ) ? 12 : 1;
        }

        if ( ! isset( $datetime['day'] ) ) {
            $datetime['day'] = ( $default_to_max ) ? (int) gmdate( 't', mktime( 0, 0, 0, $datetime['month'], 1, $datetime['year'] ) ) : 1;
        }

        if ( ! isset( $datetime['hour'] ) ) {
            $datetime['hour'] = ( $default_to_max ) ? 23 : 0;
        }

        if ( ! isset( $datetime['minute'] ) ) {
            $datetime['minute'] = ( $default_to_max ) ? 59 : 0;
        }

        if ( ! isset( $datetime['second'] ) ) {
            $datetime['second'] = ( $default_to_max ) ? 59 : 0;
        }

        return sprintf( '%04d-%02d-%02d %02d:%02d:%02d', $datetime['year'], $datetime['month'], $datetime['day'], $datetime['hour'], $datetime['minute'], $datetime['second'] );
    }

    /**
     * Builds a query string for comparing time values (hour, minute, second).
     *
     * If just hour, minute, or second is set than a normal comparison will be done.
     * However if multiple values are passed, a pseudo-decimal time will be created
     * in order to be able to accurately compare against.
     *
     * @since 3.7.0
     *
     * @global wpdb $wpdb WordPress database abstraction object.
     *
     * @param string   $column  The column to query against. Needs to be pre-validated!
     * @param string   $compare The comparison operator. Needs to be pre-validated!
     * @param int|null $hour    Optional. An hour value (0-23).
     * @param int|null $minute  Optional. A minute value (0-59).
     * @param int|null $second  Optional. A second value (0-59).
     * @return string|false A query part or false on failure.
     */
    public function build_time_query( $column, $compare, $hour = null, $minute = null, $second = null ) {
        global $wpdb;

        // Have to have at least one.
        if ( ! isset( $hour ) && ! isset( $minute ) && ! isset( $second ) ) {
            return false;
        }

        // Complex combined queries aren't supported for multi-value queries.
        if ( in_array( $compare, array( 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN' ), true ) ) {
            $return = array();

            $value = $this->build_value( $compare, $hour );
            if ( false !== $value ) {
                $return[] = "HOUR( $column ) $compare $value";
            }

            $value = $this->build_value( $compare, $minute );
            if ( false !== $value ) {
                $return[] = "MINUTE( $column ) $compare $value";
            }

            $value = $this->build_value( $compare, $second );
            if ( false !== $value ) {
                $return[] = "SECOND( $column ) $compare $value";
            }

            return implode( ' AND ', $return );
        }

        // Cases where just one unit is set.
        if ( isset( $hour ) && ! isset( $minute ) && ! isset( $second ) ) {
            $value = $this->build_value( $compare, $hour );
            if ( false !== $value ) {
                return "HOUR( $column ) $compare $value";
            }
        } elseif ( ! isset( $hour ) && isset( $minute ) && ! isset( $second ) ) {
            $value = $this->build_value( $compare, $minute );
            if ( false !== $value ) {
                return "MINUTE( $column ) $compare $value";
            }
        } elseif ( ! isset( $hour ) && ! isset( $minute ) && isset( $second ) ) {
            $value = $this->build_value( $compare, $second );
            if ( false !== $value ) {
                return "SECOND( $column ) $compare $value";
            }
        }

        // Single units were already handled. Since hour & second isn't allowed, minute must to be set.
        if ( ! isset( $minute ) ) {
            return false;
        }

        $format = '';
        $time   = '';

        // Hour.
        if ( null !== $hour ) {
            $format .= '%H.';
            $time   .= sprintf( '%02d', $hour ) . '.';
        } else {
            $format .= '0.';
            $time   .= '0.';
        }

        // Minute.
        $format .= '%i';
        $time   .= sprintf( '%02d', $minute );

        if ( isset( $second ) ) {
            $format .= '%s';
            $time   .= sprintf( '%02d', $second );
        }

        return $wpdb->prepare( "DATE_FORMAT( $column, %s ) $compare %f", $format, $time );
    }

    /**
     * Sanitizes a 'relation' operator.
     *
     * @since 6.0.3
     *
     * @param string $relation Raw relation key from the query argument.
     * @return string Sanitized relation. Either 'AND' or 'OR'.
     */
    public function sanitize_relation( $relation ) {
        if ( 'OR' === strtoupper( $relation ) ) {
            return 'OR';
        } else {
            return 'AND';
        }
    }
}