var b2g_host = 'b5togb.hkedcity.net';
var sp_host = 'ssp.proj.hkedcity.net';

function change_lang(lang, parameters) {
	var chi_url = "";
	var eng_url = "";
	var filename = gup("file");
	filename = filename.substring(filename.lastIndexOf("/") + 1);

	tc_url = 'ht'+'tp://' + sp_host + '/chi/' + filename + '?' + parameters;
	sc_url = 'ht'+'tp://' + b2g_host + '/gate/gb/' + sp_host + '/chi/' + filename + '?' + parameters;
	en_url = 'ht'+'tp://' + sp_host + '/eng/' + filename + '?' + parameters;

	if (window.location.hostname == b2g_host) {
		sc_url = tc_url;
	}

	if (lang == 'en') {
		self.location.href = en_url;
	}
	else if (lang == 'sc') {
		self.location.href = sc_url;
	}
	else {
		self.location.href = tc_url;
	}
}

function gup(name) {
	name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
	var regexS = "[\\?&]"+name+"=([^&#]*)";
	var regex = new RegExp( regexS );
	var results = regex.exec( window.location.href );
	if (results == null) {
		return "";
	}
	else {
		return results[1];
	}
}