converter.php

<?php

/** SETTINGS *************************************************************/

// Parse CLI arguments into the $_GET global.
if ( isset( $argv ) ) {
	parse_str( implode( '&', array_slice( $argv, 1 ) ), $_GET );
}

// Parse list from CLI parameters if available.
if ( ! empty( $_GET['url'] ) && ! empty( $_GET['name'] ) ) {
	$lists = [
		$_GET['name'] => $_GET['url']
	];

// Default lists.
} else {
	$lists = array(
		// Mobile Ads
		'AdguardMobileAds' => 'https://raw.githubusercontent.com/AdguardTeam/FiltersRegistry/master/filters/filter_11_Mobile/filter.txt',

		// Mobile Tracking + Spyware
		'AdguardMobileSpyware' => 'https://raw.githubusercontent.com/AdguardTeam/AdguardFilters/master/SpywareFilter/sections/mobile.txt',

		// Adguard DNS
		'AdguardDNS' => 'https://adguardteam.github.io/AdGuardSDNSFilter/Filters/filter.txt',

		// Adguard CNAME Ads
		'AdguardCNAMEAds' => 'https://raw.githubusercontent.com/AdguardTeam/cname-trackers/master/data/combined_disguised_ads.txt',

		// Adguard CNAME Clickthroughs
		'AdguardCNAMEClickthroughs' => 'https://raw.githubusercontent.com/AdguardTeam/cname-trackers/master/data/combined_disguised_clickthroughs.txt',

		// Adguard CNAME Microsites
		'AdguardCNAMEMicrosites' => 'https://raw.githubusercontent.com/AdguardTeam/cname-trackers/master/data/combined_disguised_microsites.txt',

		// Adguard CNAME Trackers
		'AdguardCNAME' => 'https://raw.githubusercontent.com/AdguardTeam/cname-trackers/master/data/combined_disguised_trackers.txt',

		// Adguard Tracking
		'AdguardTracking' => 'https://raw.githubusercontent.com/AdguardTeam/FiltersRegistry/master/filters/filter_3_Spyware/filter.txt',

		// EasyPrivacy Specific
		'EasyPrivacySpecific' => 'https://raw.githubusercontent.com/easylist/easylist/master/easyprivacy/easyprivacy_specific.txt',

		// EasyPrivacy Third-Party
		'EasyPrivacy3rdParty' => 'https://raw.githubusercontent.com/easylist/easylist/master/easyprivacy/easyprivacy_thirdparty.txt',
	);
}

/** PARSER ***************************************************************/

$idn_to_ascii = function_exists( 'idn_to_ascii' );

foreach ( $lists as $name => $list ) {
	echo "Converting {$name}...\n";

	// Fetch filter list and explode into an array.
	$lines = file_get_contents( $list );
	$lines = explode( "\n", $lines );

	// HOSTS header.
	$hosts  = "# {$name}\n";
	$hosts .= "#\n";
	$hosts .= "# Converted from - {$list}\n";
	$hosts .= "# Last converted - " . date( 'r' ) . "\n";
	$hosts .= "#\n\n";

	$domains = $exceptions = array();

	// Loop through each ad filter.
	foreach ( $lines as $filter ) {
		// Skip filter if matches the following:
		if ( false === strpos( $filter, '.' ) ) {
			continue;
		}
		if ( false !== strpos( $filter, '*' ) ) {
			continue;
		}
		if ( false !== strpos( $filter, '/' ) ) {
			continue;
		}
		if ( false !== strpos( $filter, '#' ) ) {
			continue;
		}
		if ( false !== strpos( $filter, ' ' ) ) {
			continue;
		}
		if ( false !== strpos( $filter, 'abp?' ) ) {
			continue;
		}

		// Skip Adguard HTML filtering syntax.
		if ( false !== strpos( $filter, '$$' ) || false !== strpos( $filter, '$@$' ) ) {
			continue;
		}

		// Skip domain rules.
		if ( false !== strpos( $filter, '$domain' ) || false !== strpos( $filter, ',domain' ) ) {
			continue;
		}

		// Skip third-party rules.
		if ( false !== strpos( $filter, '$third-party' ) || false !== strpos( $filter, ',third-party' ) ) {
			continue;
		}

		// Skip ping rules.
		if ( false !== strpos( $filter, '$ping' ) || false !== strpos( $filter, ',ping' ) ) {
			continue;
		}

		// Skip redirect rules.
		if ( false !== strpos( $filter, '$redirect' ) || false !== strpos( $filter, ',redirect' ) ) {
			continue;
		}

		// Skip Adguard $app rules. See #43.
		if ( false !== strpos( $filter, '$app' ) || false !== strpos( $filter, ',app' ) ) {
			continue;
		}

		// Skip Adguard $cookie rules. See #43.
		if ( false !== strpos( $filter, '$cookie' ) || false !== strpos( $filter, ',cookie' ) ) {
			continue;
		}

		// Skip Adguard $referrerpolicy rules.
		if ( false !== strpos( $filter, '$referrerpolicy' ) || false !== strpos( $filter, ',referrerpolicy' ) ) {
			continue;
		}

		// Replace filter syntax with HOSTS syntax.
		// @todo Perhaps skip $image and $popup?
		$filter = str_replace( array( '||', '^', '$all', ',all', '$image', ',image', ',important', '$script', ',script', '$object', ',object', '$popup', ',popup', '$empty', '$object-subrequest', '$document', '$subdocument', ',subdocument', '$important', '$badfilter', ',badfilter', '$websocket', '$other' ), '', $filter );

		// Skip rules matching 'xmlhttprequest' for now.
		if ( false !== strpos( $filter, 'xmlhttprequest' ) ) {
			continue;
		}

		// Skip exclusion rules.
		if ( false !== strpos( $filter, '~' ) ) {
			continue;
		}

		// Trim whitespace.
		$filter = trim( $filter );

		// If starting or ending with '.', skip.
		if ( '.' === substr( $filter, 0, 1 ) || '.' === substr( $filter, -1 ) ) {
			continue;
		}

		// If starting with '-', skip.
		// https://github.com/r-a-y/mobile-hosts/issues/5
		if ( '-' === substr( $filter, 0, 1 ) || '_' === substr( $filter, 0, 1 ) ) {
			continue;
		}

		// If starting with '!', skip.
		if ( '!' === substr( $filter, 0, 1 ) ) {
			continue;
		}

		// If starting with '|', skip.
		if ( '|' === substr( $filter, 0, 1 ) ) {
			continue;
		}

		// If ending with '=', skip.
		if ( '=' === substr( $filter, -1 ) ) {
			continue;
		}

		// If contains a comma, skip.
		if ( false !== strpos( $filter, ',' ) ) {
			continue;
		}

		// Strip trailing |.
		if ( '|' === substr( $filter, -1 ) ) {
			$filter = str_replace( '|', '', $filter );
		}

		// Skip file extensions
		if ( '.jpg' === substr( $filter, -4 ) || '.gif' === substr( $filter, -4 ) ) {
			continue;
		}

		// Skip email tracker Adguard syntax. See #34.
		if ( false !== strpos( $filter, '%' ) ) {
			continue;
		}

		// Strip port numbers.
		if ( false !== strpos( $filter, ':' ) ) {
			$filter = substr( $filter, 0, strpos( $filter, ':' ) );
		}

		// Convert internationalized domain names to punycode.
		if ( $idn_to_ascii && preg_match( "//u", $filter ) ) {
			$filter = idn_to_ascii( $filter );
		}

		// If empty, skip.
		if( empty( $filter ) ) {
			continue;
		}

		// Save exception to parse later.
		if ( 0 === strpos( $filter, '@@' ) ) {
			$exceptions[] = '0.0.0.0 ' . str_replace( '@@', '', $filter );
			continue;
		}

		$domains[] = "0.0.0.0 {$filter}";
	}

	// Generate the hosts list.
	if ( ! empty( $domains ) ) {
		// Filter out duplicates.
		$domains = array_unique( $domains );

		// Remove exceptions.
		if ( ! empty( $exceptions ) ) {
			$domains = array_diff( $domains, $exceptions );
		}

		$hosts .= implode( "\n", $domains );
		unset( $domains );
	}

	// Output the file.
	file_put_contents( "{$name}.txt", $hosts );

	echo "{$name} converted to HOSTS file - see {$name}.txt\n";
}