<?php
/**
 * Link and button rules.
 *
 * @package A11yMate
 */

namespace A11yMate\Rules\Server;

use A11yMate\Rules\Registry;
use A11yMate\Support\Html;

defined( 'ABSPATH' ) || exit;

/**
 * Names, vague text, new windows, files.
 */
class Links {

	/**
	 * Run the checks.
	 *
	 * @param Context $c Context.
	 * @return void
	 */
	public function run( Context $c ) {
		$phrases = Registry::phrases();
		$vague   = array_flip( $phrases['vague'] );
		$groups  = array();

		foreach ( $c->q( '//a[@href]' ) as $a ) {
			if ( 'true' === $a->getAttribute( 'aria-hidden' ) || Html::is_hidden( $a ) ) {
				continue;
			}
			$href = trim( $a->getAttribute( 'href' ) );
			$name = Html::accessible_name( $a, $c->xp );
			if ( '' === trim( $name ) ) {
				if ( $c->q( './/img', $a ) ) {
					continue; // Reported as a linked image with no name.
				}
				if ( '-1' === $a->getAttribute( 'tabindex' ) ) {
					continue;
				}
				$c->add( 'link-empty', $a );
				continue;
			}
			$norm = strtolower( trim( preg_replace( '/[^\p{L}\p{N}\s]+/u', '', $name ) ) );
			$norm = preg_replace( '/\s+/', ' ', $norm );
			if ( isset( $vague[ $norm ] ) ) {
				$c->add( 'link-vague', $a, array( 'text' => $name ) );
			} elseif ( '' !== $norm && 0 !== strpos( $href, '#' ) && 0 !== stripos( $href, 'javascript:' ) && 0 !== stripos( $href, 'mailto:' ) && 0 !== stripos( $href, 'tel:' ) ) {
				$groups[ $norm ][ Html::resolve( $href, $c->url ) ][] = $a;
			}

			if ( '_blank' === strtolower( $a->getAttribute( 'target' ) ) ) {
				$hint = strtolower( $name . ' ' . $a->getAttribute( 'title' ) . ' ' . $a->getAttribute( 'aria-label' ) );
				if ( ! preg_match( '/new (tab|window)|opens in|external/', $hint ) ) {
					$c->add( 'link-new-window', $a );
				}
			}

			$path = (string) wp_parse_url( $href, PHP_URL_PATH );
			$ext  = strtolower( pathinfo( $path, PATHINFO_EXTENSION ) );
			if ( '' !== $ext && in_array( $ext, $phrases['fileExtensions'], true ) && false === stripos( $name, $ext ) && ! preg_match( '/download|document|file/i', $name ) ) {
				$c->add( 'link-file-no-type', $a, array( 'extension' => $ext ) );
			}
		}

		foreach ( $groups as $text => $dests ) {
			if ( count( $dests ) < 2 ) {
				continue;
			}
			$n = 0;
			foreach ( $dests as $dest => $links ) {
				$c->add(
					'link-same-text-different-dest',
					$links[0],
					array(
						'text'         => $text,
						'destinations' => count( $dests ),
					)
				);
				if ( ++$n >= 4 ) {
					break;
				}
			}
		}

		foreach ( $c->q( "//button | //*[@role='button'] | //input[@type='button' or @type='submit' or @type='reset']" ) as $b ) {
			if ( 'true' === $b->getAttribute( 'aria-hidden' ) || Html::is_hidden( $b ) ) {
				continue;
			}
			if ( '' === trim( Html::accessible_name( $b, $c->xp ) ) ) {
				$c->add( 'button-empty', $b );
			}
		}
	}
}