-function updatelinks(lon,lat,zoom) {
- var links = new Array();
- links['viewanchor'] = '/index.html';
- //links['editanchor'] = 'edit.html';
- links['uploadanchor'] = '/traces';
- links['loginanchor'] = '/login.html';
- links['logoutanchor'] = '/logout.html';
- links['registeranchor'] = '/create-account.html';
-
- var node;
- var anchor;
- for (anchor in links) {
- node = document.getElementById(anchor);
- if (! node) { continue; }
- node.href = links[anchor] + "?lat=" + lat + "&lon=" + lon + "&zoom=" + zoom;
- }
-
- node = document.getElementById("editanchor");
- if (node) {
- if ( zoom >= 14) {
- node.href = '/edit.html?lat=' + lat + '&lon=' + lon + "&zoom=" + zoom;
- node.style.fontStyle = 'normal';
+/*
+ * Called as the user scrolls/zooms around to aniplate hrefs of the
+ * view tab and various other links
+ */
+function updatelinks(lon,lat,zoom,layers,minlon,minlat,maxlon,maxlat,objtype,objid) {
+ var decimals = Math.pow(10, Math.floor(zoom/3));
+ var node;
+
+ lat = Math.round(lat * decimals) / decimals;
+ lon = Math.round(lon * decimals) / decimals;
+
+ node = document.getElementById("permalinkanchor");
+ if (node) {
+ var args = getArgs(node.href);
+ args["lat"] = lat;
+ args["lon"] = lon;
+ args["zoom"] = zoom;
+ if (layers) {
+ args["layers"] = layers;
+ }
+ if (objtype && objid) {
+ args[objtype] = objid;
+ }
+ node.href = setArgs(node.href, args);
+ }
+
+ node = document.getElementById("viewanchor");
+ if (node) {
+ var args = getArgs(node.href);
+ args["lat"] = lat;
+ args["lon"] = lon;
+ args["zoom"] = zoom;
+ if (layers) {
+ args["layers"] = layers;
+ }
+ node.href = setArgs(node.href, args);
+ }
+
+ node = document.getElementById("exportanchor");
+ if (node) {
+ var args = getArgs(node.href);
+ args["lat"] = lat;
+ args["lon"] = lon;
+ args["zoom"] = zoom;
+ if (layers) {
+ args["layers"] = layers;
+ }
+ node.href = setArgs(node.href, args);
+ }
+
+ node = document.getElementById("editanchor");
+ if (node) {
+ if (zoom >= 13) {
+ var args = new Object();
+ args.lat = lat;
+ args.lon = lon;
+ args.zoom = zoom;
+ node.href = setArgs("/edit", args);
+ node.style.fontStyle = 'normal';
+ } else {
+ node.href = 'javascript:alert("zoom in to edit map");';
+ node.style.fontStyle = 'italic';
+ }
+ }
+
+ node = document.getElementById("historyanchor");
+ if (node) {
+ if (zoom >= 11) {
+ var args = new Object();
+ //set bbox param from 'extents' object
+ if (typeof minlon == "number" &&
+ typeof minlat == "number" &&
+ typeof maxlon == "number" &&
+ typeof maxlat == "number") {
+
+ minlon = Math.round(minlon * decimals) / decimals;
+ minlat = Math.round(minlat * decimals) / decimals;
+ maxlon = Math.round(maxlon * decimals) / decimals;
+ maxlat = Math.round(maxlat * decimals) / decimals;
+ args.bbox = minlon + "," + minlat + "," + maxlon + "," + maxlat;
+ }
+
+ node.href = setArgs("/history", args);
+ node.style.fontStyle = 'normal';
} else {
- node.href = 'javascript:alert("zoom in to edit map");';
- node.style.fontStyle = 'italic';
+ node.href = 'javascript:alert("zoom in to see editing history");';
+ node.style.fontStyle = 'italic';
+ }
+ }
+
+ node = document.getElementById("shortlinkanchor");
+ if (node) {
+ var args = getArgs(node.href);
+ var code = makeShortCode(lat, lon, zoom);
+ var prefix = shortlinkPrefix();
+
+ // Add ?{node,way,relation}=id to the arguments
+ if (objtype && objid) {
+ args[objtype] = objid;
+ }
+
+ // This is a hack to omit the default mapnik layer (B000FTF) from
+ // the shortlink. B000FTFT is then the "Object" layer which we get
+ // on /?{node,way,relation}=id
+ if (layers && (layers != "B000FTF") && (layers != "B000FTFT")) {
+ args["layers"] = layers;
+ }
+
+ // Here we're assuming that all parameters but ?layers= and
+ // ?{node,way,relation}= can be safely omitted from the shortlink
+ // which encodes lat/lon/zoom. If new URL parameters are added to
+ // the main slippy map this needs to be changed.
+ if (args["layers"] || args[objtype]) {
+ node.href = setArgs(prefix + "/go/" + code, args);
+ } else {
+ node.href = prefix + "/go/" + code;
+ }
+ }
+}
+
+/*
+ * Get the URL prefix to use for a short link
+ */
+function shortlinkPrefix() {
+ if (window.location.hostname.match(/^www\.openstreetmap\.org/i)) {
+ return "http://osm.org";
+ } else {
+ return "";
+ }
+}
+
+/*
+ * Called to get the arguments from a URL as a hash.
+ */
+function getArgs(url) {
+ var args = new Object();
+ var querystart = url.indexOf("?");
+
+ if (querystart >= 0) {
+ var querystring = url.substring(querystart + 1);
+ var queryitems = querystring.split("&");
+
+ for (var i = 0; i < queryitems.length; i++) {
+ if (match = queryitems[i].match(/^(.*)=(.*)$/)) {
+ args[unescape(match[1])] = unescape(match[2]);
+ } else {
+ args[unescape(queryitems[i])] = null
+ }
+ }
+ }
+
+ return args;
+}
+
+/*
+ * Called to set the arguments on a URL from the given hash.
+ */
+function setArgs(url, args) {
+ var queryitems = new Array();
+
+ for (arg in args)
+ {
+ if (args[arg] == null) {
+ queryitems.push(escape(arg));
+ } else {
+ queryitems.push(escape(arg) + "=" + escape(args[arg]));
+ }
+ }
+
+ return url.replace(/\?.*$/, "") + "?" + queryitems.join("&");
+}
+
+/*
+ * Called to get a CSS property for an element.
+ */
+function getStyle(el, property) {
+ var style;
+
+ if (el.currentStyle) {
+ style = el.currentStyle[property];
+ } else if( window.getComputedStyle ) {
+ style = document.defaultView.getComputedStyle(el,null).getPropertyValue(property);
+ } else {
+ style = el.style[property];
+ }
+
+ return style;
+}
+
+/*
+ * Called to interpolate JavaScript variables in strings using a
+ * similar syntax to rails I18n string interpolation - the only
+ * difference is that [[foo]] is the placeholder syntax instead
+ * of {{foo}} which allows the same string to be processed by both
+ * rails and then later by javascript.
+ */
+function i18n(string, keys) {
+ for (var key in keys) {
+ var re_key = '\\[\\[' + key + '\\]\\]';
+ var re = new RegExp(re_key, "g");
+
+ string = string.replace(re, keys[key]);
+ }
+
+ return string;
+}
+
+function makeShortCode(lat, lon, zoom) {
+ char_array = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_@";
+ var x = Math.round((lon + 180.0) * ((1 << 30) / 90.0));
+ var y = Math.round((lat + 90.0) * ((1 << 30) / 45.0));
+ // hack around the fact that JS apparently only allows 53-bit integers?!?
+ // note that, although this reduces the accuracy of the process, it's fine for
+ // z18 so we don't need to care for now.
+ var c1 = 0, c2 = 0;
+ for (var i = 31; i > 16; --i) {
+ c1 = (c1 << 1) | ((x >> i) & 1);
+ c1 = (c1 << 1) | ((y >> i) & 1);
+ }
+ for (var i = 16; i > 1; --i) {
+ c2 = (c2 << 1) | ((x >> i) & 1);
+ c2 = (c2 << 1) | ((y >> i) & 1);
+ }
+ var str = "";
+ for (var i = 0; i < Math.ceil((zoom + 8) / 3.0) && i < 5; ++i) {
+ digit = (c1 >> (24 - 6 * i)) & 0x3f;
+ str += char_array.charAt(digit);
+ }
+ for (var i = 5; i < Math.ceil((zoom + 8) / 3.0); ++i) {
+ digit = (c2 >> (24 - 6 * (i - 5))) & 0x3f;
+ str += char_array.charAt(digit);
}
+ for (var i = 0; i < ((zoom + 8) % 3); ++i) {
+ str += "=";
}
+ return str;
}