<?php

use WP_CLI\CommandWithMeta;
use WP_CLI\Fetchers\Post as PostFetcher;

/**
 * Adds, updates, deletes, and lists post custom fields.
 *
 * ## EXAMPLES
 *
 *     # Set post meta
 *     $ wp post meta set 123 _wp_page_template about.php
 *     Success: Updated custom field '_wp_page_template'.
 *
 *     # Get post meta
 *     $ wp post meta get 123 _wp_page_template
 *     about.php
 *
 *     # Update post meta
 *     $ wp post meta update 123 _wp_page_template contact.php
 *     Success: Updated custom field '_wp_page_template'.
 *
 *     # Delete post meta
 *     $ wp post meta delete 123 _wp_page_template
 *     Success: Deleted custom field.
 */
class Post_Meta_Command extends CommandWithMeta {
    protected $meta_type = 'post';

    /**
     * Check that the post ID exists
     *
     * @param int
     */
    protected function check_object_id( $object_id ) {
        $fetcher = new PostFetcher();
        $post    = $fetcher->get_check( $object_id );
        return $post->ID;
    }

    /**
     * Wrapper method for add_metadata that can be overridden in sub classes.
     *
     * @param int    $object_id  ID of the object the metadata is for.
     * @param string $meta_key   Metadata key to use.
     * @param mixed  $meta_value Metadata value. Must be serializable if
     *                           non-scalar.
     * @param bool   $unique     Optional, default is false. Whether the
     *                           specified metadata key should be unique for the
     *                           object. If true, and the object already has a
     *                           value for the specified metadata key, no change
     *                           will be made.
     *
     * @return int|false The meta ID on success, false on failure.
     */
    protected function add_metadata( $object_id, $meta_key, $meta_value, $unique = false ) {
        return add_post_meta( $object_id, $meta_key, $meta_value, $unique );
    }

    /**
     * Wrapper method for update_metadata that can be overridden in sub classes.
     *
     * @param int    $object_id  ID of the object the metadata is for.
     * @param string $meta_key   Metadata key to use.
     * @param mixed  $meta_value Metadata value. Must be serializable if
     *                           non-scalar.
     * @param mixed  $prev_value Optional. If specified, only update existing
     *                           metadata entries with the specified value.
     *                           Otherwise, update all entries.
     *
     * @return int|bool Meta ID if the key didn't exist, true on successful
     *                  update, false on failure.
     */
    protected function update_metadata( $object_id, $meta_key, $meta_value, $prev_value = '' ) {
        return update_post_meta( $object_id, $meta_key, $meta_value, $prev_value );
    }

    /**
     * Wrapper method for get_metadata that can be overridden in sub classes.
     *
     * @param int    $object_id ID of the object the metadata is for.
     * @param string $meta_key  Optional. Metadata key. If not specified,
     *                          retrieve all metadata for the specified object.
     * @param bool   $single    Optional, default is false. If true, return only
     *                          the first value of the specified meta_key. This
     *                          parameter has no effect if meta_key is not
     *                          specified.
     *
     * @return mixed Single metadata value, or array of values.
     */
    protected function get_metadata( $object_id, $meta_key = '', $single = false ) {
        return get_post_meta( $object_id, $meta_key, $single );
    }

    /**
     * Wrapper method for delete_metadata that can be overridden in sub classes.
     *
     * @param int    $object_id  ID of the object metadata is for
     * @param string $meta_key   Metadata key
     * @param mixed  $meta_value  Optional. Metadata value. Must be serializable
     *                            if non-scalar. If specified, only delete
     *                            metadata entries with this value. Otherwise,
     *                            delete all entries with the specified meta_key.
     *                            Pass `null, `false`, or an empty string to skip
     *                            this check. For backward compatibility, it is
     *                            not possible to pass an empty string to delete
     *                            those entries with an empty string for a value.
     *
     * @return bool True on successful delete, false on failure.
     */
    protected function delete_metadata( $object_id, $meta_key, $meta_value = '' ) {
        return delete_post_meta( $object_id, $meta_key, $meta_value );
    }

    /**
     * Cleans up duplicate post meta values on a post.
     *
     * ## OPTIONS
     *
     * <id>
     * : ID of the post to clean.
     *
     * <key>
     * : Meta key to clean up.
     *
     * ## EXAMPLES
     *
     *     # Delete duplicate post meta.
     *     wp post meta clean-duplicates 1234 enclosure
     *     Success: Cleaned up duplicate 'enclosure' meta values.
     *
     * @subcommand clean-duplicates
     */
    public function clean_duplicates( $args, $assoc_args ) {
        global $wpdb;

        list( $post_id, $key ) = $args;

        $metas = $wpdb->get_results(
            $wpdb->prepare(
                "SELECT * FROM {$wpdb->postmeta} WHERE meta_key=%s AND post_id=%d",
                $key,
                $post_id
            )
        );

        if ( empty( $metas ) ) {
            WP_CLI::error( sprintf( 'No meta values found for \'%s\'.', $key ) );
        }

        $uniq_metas = array();
        $dupe_metas = array();
        foreach ( $metas as $meta ) {
            if ( ! isset( $uniq_metas[ $meta->meta_value ] ) ) {
                $uniq_metas[ $meta->meta_value ] = (int) $meta->meta_id;
            } else {
                $dupe_metas[] = (int) $meta->meta_id;
            }
        }

        if ( count( $dupe_metas ) ) {
            WP_CLI::confirm(
                sprintf(
                    'Are you sure you want to delete %d duplicate meta values and keep %d valid meta value?',
                    count( $dupe_metas ),
                    count( $uniq_metas )
                )
            );
            foreach ( $dupe_metas as $meta_id ) {
                delete_metadata_by_mid( 'post', $meta_id );
                WP_CLI::log( sprintf( 'Deleted meta id %d.', $meta_id ) );
            }
            WP_CLI::success( sprintf( 'Cleaned up duplicate \'%s\' meta values.', $key ) );
        } else {
            WP_CLI::success(
                sprintf(
                    'Nothing to clean up: found %d valid meta value and %d duplicates.',
                    count( $uniq_metas ),
                    count( $dupe_metas )
                )
            );
        }
    }
}