Hard code osm.org into the shortcode permalink.

[rails.git] / public / javascripts / site.js

diff --git a/public/javascripts/site.js b/public/javascripts/site.js
index ae38ecb6a53914239c903a252ba9aa4d83c13d57..aefd9c8b68fd2044119c255b6048f8698c41ca18 100644 (file)
--- a/public/javascripts/site.js
+++ b/public/javascripts/site.js
@@ -1,5 +1,7 @@
-//Called as the user scrolls/zooms around.
-//Maniplate hrefs of the view tab and various other links
+/*
+ * 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) {
   var decimals = Math.pow(10, Math.floor(zoom/3));
   var node;
 function updatelinks(lon,lat,zoom,layers,minlon,minlat,maxlon,maxlat) {
   var decimals = Math.pow(10, Math.floor(zoom/3));
   var node;


@@ -45,7 +47,7 @@ function updatelinks(lon,lat,zoom,layers,minlon,minlat,maxlon,maxlat) {
 
   node = document.getElementById("editanchor");
   if (node) {
 
   node = document.getElementById("editanchor");
   if (node) {

-    if (zoom >= 11) {
+    if (zoom >= 13) {

       var args = new Object();
       args.lat = lat;
       args.lon = lon;
       var args = new Object();
       args.lat = lat;
       args.lon = lon;


@@ -82,6 +84,20 @@ function updatelinks(lon,lat,zoom,layers,minlon,minlat,maxlon,maxlat) {
       node.style.fontStyle = 'italic';
     }
   }
       node.style.fontStyle = 'italic';
     }
   }

+
+  node = document.getElementById("shortlinkanchor");
+  if (node) {
+    var args = getArgs(node.href);
+    var code = makeShortCode(lat, lon, zoom);
+    // little hack. may the gods of hardcoding please forgive me, or 
+    // show me the Right way to do it.
+    if (layers && (layers != "B000FTF")) {
+      args["layers"] = layers;
+      node.href = setArgs("http://osm.org/go/" + code, args);
+    } else {
+      node.href = "http://osm.org/go/" + code;
+    }
+  }

 }
 
 function getArgs(url) {
 }
 
 function getArgs(url) {


@@ -104,6 +120,9 @@ function getArgs(url) {
   return args;
 }
 
   return args;
 }
 

+/*
+ * Called to set the arguments on a URL from the given hash.
+ */

 function setArgs(url, args) {
    var queryitems = new Array();
 
 function setArgs(url, args) {
    var queryitems = new Array();
 


@@ -119,6 +138,9 @@ function setArgs(url, args) {
    return url.replace(/\?.*$/, "") + "?" + queryitems.join("&");
 }
 
    return url.replace(/\?.*$/, "") + "?" + queryitems.join("&");
 }
 

+/*
+ * Called to get the arguments from a URL as a hash.
+ */

 function getStyle(el, property) {
   var style;
 
 function getStyle(el, property) {
   var style;
 


@@ -132,3 +154,52 @@ function getStyle(el, property) {
 
   return style;
 }
 
   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;
+}