<?php

// exit if accessed directly
if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

// exit if we can't extend Attachments
if ( ! class_exists( 'Attachments' ) ) {
    exit;
}


/**
* Search Attachments metadata based on a number of parameters
*
* @since 3.4.1
*/
class AttachmentsSearch extends Attachments {

    public $results;

    /**
     * Facilitates searching for Attachments
     *
     * @since 3.3
     */
    function __construct( $query = null, $params = array() ) {
        parent::__construct();
        $this->apply_init_filters();

        $defaults = array(
                'attachment_id' => null,            // not searching for a single attachment ID
                'instance'      => 'attachments',   // default instance
                'post_type'     => null,            // search 'any' post type
                'post_id'       => null,            // searching all posts
                'post_status'   => 'publish',       // search only published posts
                'fields'        => null,            // search all fields
                'filetype'      => null,            // search all filetypes
            );

        $query  = is_null( $query ) ? null : sanitize_text_field( $query );
        $params = array_merge( $defaults, $params );

        // sanitize parameters
        $params['attachment_id']    = is_null( $params['attachment_id'] ) ? null : intval( $params['attachment_id'] );
        $params['instance']         = !is_string( $params['instance'] ) ? 'attachments' : sanitize_text_field( $params['instance'] );
        $params['post_type']        = is_null( $params['post_type'] ) ? 'any' : sanitize_text_field( $params['post_type'] );
        $params['post_id']          = is_null( $params['post_id'] ) ? null : intval( $params['post_id'] );

        $params['post_status']      = sanitize_text_field( $params['post_status'] );

        if( is_string( $params['fields'] ) ) {
            $params['fields']       = array( $params['fields'] );   // we always want an array
        }

        if( is_string( $params['filetype'] ) ) {
            $params['filetype']     = array( $params['filetype'] ); // we always want an array
        }

        // since we have an array for our fields, we need to loop through and sanitize
        for ( $i = 0; $i < count( $params['fields'] ); $i++ ) {
            $params['fields'][ $i ] = sanitize_text_field( $params['fields'][ $i ] );
        }

        // prepare our search args
        $args = array(
                'nopaging'      => true,
                'post_status'   => $params['post_status'],
                'meta_query'    => array(
                        array(
                                'key'       => parent::get_meta_key(),
                                'value'     => $query,
                                'compare'   => 'LIKE'
                            )
                    ),
            );

        // append any applicable parameters that got passed to the original method call
        if( $params['post_type'] ) {
            $args['post_type'] = $params['post_type'];
        }

        if( $params['post_id'] ) {
            $args['post__in'] = array( $params['post_id'] );    // avoid using 'p' or 'page_id'
        }

        // we haven't utilized all parameters yet because they're meta-value based so we need to
        // do some parsing on our end to validate the returned results

        $possible_posts         = new WP_Query( $args );
        $potential_attachments  = false;  // stores valid attachments as restrictions are added

        if ( $possible_posts->found_posts ) {
            // we have results from the reliminary search, we need to quantify them
            while ( $possible_posts->have_posts() ) {
                $possible_posts->next_post();
                $possible_post_ids[] = $possible_posts->post->ID;
            }

            // now that we have our possible post IDs we can grab all Attachments for all of those posts
            foreach ( $possible_post_ids as $possible_post_id ) {
                $possible_attachments = parent::get_attachments( $params['instance'], $possible_post_id );

                foreach ( $possible_attachments as $possible_attachment ) {
                    $potential_attachments[] = $possible_attachment;
                }
            }

        }

        // if there aren't even any potential attachments, we'll just short circuit
        if ( ! $potential_attachments ) {
            return;
        }

        // first we need to make sure that our query matches each attachment
        // we need to do this because the LIKE query returned the entire meta record,
        // not necessarily tied to any specific Attachment
        $total_potentials = count( $potential_attachments );
        for( $i = 0; $i < $total_potentials; $i++ ) {
            $valid = false;

            // if we need to limit our search to specific fields, we'll do that here
            if ( $params['fields'] ) {
                // we only want to check certain fields
                foreach ( $params['fields'] as $field ) {
                    if( isset( $potential_attachments[$i]->fields->$field ) ) {  // does the field exist?
                        if( empty( $query ) || strpos( strtolower( $potential_attachments[$i]->fields->$field ),
                                    strtolower( $query ) ) !== false ) { // does the value match?
                            if( is_null( $params['filetype'] ) || ( !is_null( $params['filetype'] ) && in_array( parent::get_mime_type( $potential_attachments[ $i ]->id ), $params['filetype'] ) ) ) {
                                $valid = true;
                            }
                        }
                    }
                }
            } else {
                // we want to check all fields
                if ( isset( $potential_attachments[$i]->fields ) ) {
                    foreach ( $potential_attachments[$i]->fields as $field_name => $field_value ) {
                        if ( empty( $query ) || strpos( strtolower( $field_value) , strtolower( $query ) ) !== false ) {
                            if ( is_null( $params['filetype'] ) || ( !is_null( $params['filetype'] ) && in_array( parent::get_mime_type( $potential_attachments[ $i ]->id ), $params['filetype'] ) ) ) {
                                $valid = true;
                            }
                        }
                    }
                }
            }

            if ( ! $valid ) {
                unset( $potential_attachments[ $i ] );
            }

            // now our potentials have been limited to each match the query based on any field
        }

        // limit to attachment ID if applicable
        if ( $params['attachment_id'] ) {
            foreach ( $potential_attachments as $key => $value ) {
                if ( $potential_attachments[ $key ]->id != $params['attachment_id'] ) {
                    unset( $potential_attachments[$key] );
                }
            }
        }

        $this->results = array_values( $potential_attachments );
    }
}