// AJAX Nominatim Call
// 16.04.2011
// Gerit Wissing

function GetXmlHttpObject() {
	try {
		// Firefox. Opera, Sarafi
		try {  // get firefox to do cross domain ajax 
			netscape.security.PrivilegeManager.enablePrivilege("UniversalBrowserRead");
			netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");
		} catch (err) {
			//alert("Error initializing XMLHttpRequest.\n"+err); // show error
		}
		xmlHttp = new XMLHttpRequest(); // instantiate it regardless of security
	}
	catch(err) {
		// Internet Explorer
		try {
			xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
		} catch(err) {
			xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
		}
	}
	return xmlHttp;
}

function ajax(url, callback, infotext) {
	var xmlhttp = GetXmlHttpObject();
	//alert(url);
	if (xmlhttp) {
		//alert('doit');
		xmlhttp.open("GET", url, true);
		xmlhttp.onreadystatechange=function(){
			//alert('readyState = ' + xmlhttp.readyState + ' / status = ' + xmlhttp.status);
			if ( xmlhttp.readyState == 4  ) {
				//alert(xmlhttp.responseText);
				callback(xmlhttp, infotext);
			}
		}
		xmlhttp.send(null);
	}
}

function nominatim(searchtext) {
	var url='./api/nominatim.php?q='+searchtext;
	ajax(url, nominatim_callback, infotext=searchtext);
}

function nominatim_callback(xmlHttp, infotext) {
	if ( xmlHttp.status == 0 ) {
		alert('"'+infotext+' not found.');
	} else if ( xmlHttp.status == 200 ) {
		if ( xmlHttp.responseXML.getElementsByTagName('place')[0] ) {   // is one place returned?
			addSearchResults(xmlHttp);
		} else {
			alert('"'+infotext+'" not found.');
		}
	}
}


// in addition to the CC-BY-SA of the wiki feel free to use the following source for any purpose without restrictions (PD)
// credits and additions appreciated: http://wiki.openstreetmap.org/wiki/User:Stephankn
 
function checkJOSM(version){
   alert(version.application + " uses protocol version " + version.protocolversion.major + "." + version.protocolversion.minor);
   // do something useful, maybe showing edit button
}

function getJOSMVersion() {
	var url = "http://127.0.0.1:8111/version";
	var useFallback = false;
	// currently FF3.5, Safari 4 and IE8 implement CORS
	if (XMLHttpRequest) {
	   var request = new XMLHttpRequest();
	   if ("withCredentials" in request) {
	      request.open('GET', url, true);
	      request.onreadystatechange = function(){
	         if (request.readyState != 4) {
	            return;
	         }
	         if (request.status == 200) {
	            checkJOSM(eval('(' + request.responseText + ')'));
	         }
	      };
	      request.send();
	   }
	   else if (XDomainRequest) {
	      var xdr = new XDomainRequest();
	      try {
	         xdr.open("get", url);
	         xdr.onload = function(){
	            checkJOSM(eval('(' + xdr.responseText + ')'));
	         };
	         xdr.send();
	      } catch (e) {
	         useFallback = true;
	      }
	   } else {
	      useFallback = true;
	   }
	}
	else {
	   // no XMLHttpRequest available
	   useFallback = true;
	}
	 
	if (useFallback) {
	   // Use legacy jsonp call
	   var s = document.createElement('script');
	   s.src = url + '?jsonp=checkJOSM';
	   s.type = 'text/javascript';
	 
	   if (document.getElementsByTagName('head').length > 0) {
	      document.getElementsByTagName('head')[0].appendChild(s);
	   }
	}
}

function josm_call() {
	left    = x2lon( map.getExtent().left   ).toFixed(5);
	right   = x2lon( map.getExtent().right  ).toFixed(5);
	// conflict with use of variable 'top' in internet explorer. (why?) use my_top instead. gw
	my_top    = y2lat( map.getExtent().top    ).toFixed(5);
	bottom  = y2lat( map.getExtent().bottom ).toFixed(5);
	baseUrl = 'http://127.0.0.1:8111/load_and_zoom?left='+left+'&right='+right+'&top='+my_top+'&bottom='+bottom;
	// IE 9 + localhost ajax GEHT NICHT, daher Fallback:
	//window.open (baseUrl);
	document.getElementById('josm_call_iframe').src=baseUrl;
}