define_tag(
	'assets',
	-namespace='cache_',
	-req='in', -type='array',
	-opt='target', -type='string',
	-opt='usecache', -type='boolean',
	-opt='refresh', -type='boolean',
	-opt='minify', -type='boolean',
	-opt='compress', -type='boolean',
	-priority='replace',
	-encodenone,
	-description='Concatenates, minifies, and compresses JS and CSS files and returns a link to the resulting file(s).'
);
	local('srcfiles') = #in;

	local(
		'out' 		= string,
		'cacheid'	= string,
		'cachepath'	= string,
		'tempdata'	= string,
		'cachetype'	= #srcfiles->first->split('.')->last
	);
	
	local('defaults') = array(
		'target'	= '/site/' + (#cachetype == 'js' ? 'scripts' | 'styles') + '/cache/',
		'usecache'	= true,
		'refresh'	= false,
		'minify'	= true,
		'compress'	= true
	);
	
	iterate(#defaults, local('i'));
		!local_defined(#i->first) ? local(#i->first) = #i->second;
	/iterate;

	// if caching is on	
	if(#usecache);		
		// generate unique path for the cached file per the given list of source files
		local('token') = string;
		
		iterate(#srcfiles, local('i'));
			local('d') = file_moddate(#i);
			#token += #i + #d;
		/iterate;
					
		#cacheid = encrypt_hmac(
			-token=#token,
			-password=server_name,
			-digest='md5',
			-cram		
		);
		
		!#target->endswith('/') ? #target += '/';
		#cachepath = #target + #cacheid + '.' + #cachetype;

		// if refresh command is given or cached file is not found
		if(#refresh || !file_exists(#cachepath));
			// concatenate source files into cached file
			iterate(#srcfiles, local('i'));
				local('src') = (#cachetype == 'css' ? css_normalizeurls(#i) | string(include_raw(#i)));
				#tempdata += #src + '\n\n';
			/iterate;
							
			// if using minification
			if(#minify);				
				// compress/pack/minify cached file (YUI can handle both js and css)
				file_write(#cachepath, #tempdata, -fileoverwrite);
				#tempdata = yui_compress(server_webroot + #cachepath);
				#cachepath->replace('.' + #cachetype,'-min.' + #cachetype);
			/if;
			
			if(#compress);
				// gzip result
				#tempdata = compress_gzip(#tempdata);
				#cachepath += '.gz';
			/if;
			
			// write cached file to disk
			file_write(#cachepath, #tempdata, -fileoverwrite);
		/if;
		
		// make sure cachepath is correct even when not refreshing
		#minify && #cachepath !>> '-min' ? #cachepath->replace('.' + #cachetype,'-min.' + #cachetype);
		#compress && !#cachepath->endswith('.gz') ? #cachepath += '.gz';
		
		// generate link to cached file
		if(#cachetype == 'js');
			#out += '\n';
		else;
			#out += '\n';
		/if;
	
	// else just generate separate links for the individual source files
	else;	
		iterate(#srcfiles, local('i'));
			if(#cachetype == 'js');
				#out += '\n';
			else(#cachetype == 'css');
				#out += '\n';
			/if;
		/iterate;
	/if;
	
	return(#out);
/define_tag;