<?php
/**
 * Term matching with aliases. "Sala Ziemi", "MTP Sala Ziemi" and
 * "sala ziemi poznań" can all point to the same venue.
 *
 * @package BeariusCalendar
 */

defined( 'ABSPATH' ) || exit;

/**
 * Normalizes a name for comparison.
 *
 * @param string $name Name.
 * @return string
 */
function bcal_normalize_name( $name ) {
	$name = remove_accents( wp_strip_all_tags( (string) $name ) );
	$name = function_exists( 'mb_strtolower' ) ? mb_strtolower( $name ) : strtolower( $name );
	$name = preg_replace( '/[^a-z0-9]+/', ' ', $name );
	return trim( preg_replace( '/\s+/', ' ', (string) $name ) );
}

/**
 * Stores aliases for a term.
 *
 * @param int    $term_id Term ID.
 * @param string $raw     Comma or newline separated aliases.
 */
function bcal_save_aliases( $term_id, $raw ) {
	$raw = sanitize_textarea_field( (string) $raw );
	update_term_meta( $term_id, 'bcal_aliases', $raw );
	delete_term_meta( $term_id, 'bcal_alias_norm' );

	$seen = array();
	foreach ( preg_split( '/[,\n\r]+/', $raw ) as $alias ) {
		$norm = bcal_normalize_name( $alias );
		if ( '' !== $norm && ! isset( $seen[ $norm ] ) ) {
			add_term_meta( $term_id, 'bcal_alias_norm', $norm );
			$seen[ $norm ] = true;
		}
	}
}

/**
 * Finds or creates a term by name, checking names, slugs and aliases.
 *
 * @param string $taxonomy Taxonomy.
 * @param string $name     Name.
 * @param bool   $create   Create when missing.
 * @return int Term ID or 0.
 */
function bcal_resolve_term( $taxonomy, $name, $create = true ) {
	$name = trim( wp_strip_all_tags( (string) $name ) );
	if ( '' === $name ) {
		return 0;
	}

	$term = get_term_by( 'name', $name, $taxonomy );
	if ( $term ) {
		return (int) $term->term_id;
	}

	$term = get_term_by( 'slug', sanitize_title( $name ), $taxonomy );
	if ( $term ) {
		return (int) $term->term_id;
	}

	$norm = bcal_normalize_name( $name );
	if ( '' !== $norm ) {
		$found = get_terms(
			array(
				'taxonomy'   => $taxonomy,
				'hide_empty' => false,
				'number'     => 1,
				'fields'     => 'ids',
				'meta_key'   => 'bcal_alias_norm', // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_key
				'meta_value' => $norm, // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_value
			)
		);
		if ( ! is_wp_error( $found ) && $found ) {
			return (int) $found[0];
		}
	}

	if ( ! $create ) {
		return 0;
	}

	$result = wp_insert_term( $name, $taxonomy );
	if ( is_wp_error( $result ) ) {
		$existing = $result->get_error_data( 'term_exists' );
		return $existing ? (int) $existing : 0;
	}

	return (int) $result['term_id'];
}

/**
 * Converts a comma separated list of slugs or IDs to term IDs.
 *
 * @param string|array $value    Slugs or IDs.
 * @param string       $taxonomy Taxonomy.
 * @return array
 */
function bcal_terms_to_ids( $value, $taxonomy ) {
	$items = is_array( $value ) ? $value : explode( ',', (string) $value );
	$ids   = array();

	foreach ( $items as $item ) {
		$item = trim( (string) $item );
		if ( '' === $item ) {
			continue;
		}
		if ( ctype_digit( $item ) ) {
			$ids[] = (int) $item;
			continue;
		}
		$term = get_term_by( 'slug', sanitize_title( $item ), $taxonomy );
		if ( $term ) {
			$ids[] = (int) $term->term_id;
		}
	}

	return array_values( array_unique( $ids ) );
}