Revert "remove css"

This reverts commit ad4780c.

index.js

@@ -1,7 +1,41 @@
 var fs = require('fs');
 var mimer = require('mimer');
+var sha1 = require('sha1');
 var through = require('through');
 
+function insertRequiresIntoCSS(data) {
+  var re = /require\(["'](.*?)["']\)/;
+  var pieces = data.split(re);
+  return pieces.map(function(piece, index) {
+    var isRequire = index % 2 === 1;
+    if (!isRequire) {
+      return JSON.stringify(piece);
+    } else {
+      return '"url(" + require(' + JSON.stringify(piece) + ') + ")"';
+    }
+  }).join(' + ');
+}
+
+function transformCSS(data) {
+  var code = '';
+  var nodeID = '__staticify_style__' + sha1(data);
+  code += 'var nodeID = ' + JSON.stringify(nodeID) + ';\n';
+  code += 'var code = ' + insertRequiresIntoCSS(data) + ';\n';
+  code += 'if (typeof window === \'undefined\') {\n';
+  code += '  var g = eval(\'global\');\n'; // bypass browserify global insertion
+  code += '  if (!g.__staticify_css) {\n';
+  code += '    g.__staticify_css = [];\n';
+  code += '  }\n';
+  code += '  g.__staticify_css.push({nodeID: nodeID, code: code});\n';
+  code += '} else if (!document.getElementById(nodeID)) {\n';
+  code += '  var node = document.createElement(\'style\');\n';
+  code += '  node.setAttribute(\'id\', nodeID);\n';
+  code += '  node.innerHTML = code;\n';
+  code += '  document.head.appendChild(node);\n';
+  code += '}\n';
+  return code;
+}
+
 function transformImage(data, filename) {
   var uri = 'data:' + mimer(filename) + ';base64,' + data;
   return 'module.exports = ' + JSON.stringify(uri) + ';\n';
@@ -20,6 +54,10 @@ function isImage(filename) {
   return hasExt(filename, ['.png', '.jpg', '.gif']);
 }
 
+function isCSS(filename) {
+  return hasExt(filename, ['.css', '.sass', '.scss', '.less']);
+}
+
 function transformer(func, args) {
   var buf = '';
   return through(
@@ -58,6 +96,8 @@ module.exports = function(filename) {
     return guardWrites(
       fs.createReadStream(filename, {encoding: 'base64'})
         .pipe(transformer(transformImage, [filename])))
+  } else if (isCSS(filename)) {
+    return transformer(transformCSS, [filename]);
   } else {
     return through();
   }

package.json

@@ -8,7 +8,8 @@
   },
   "dependencies": {
     "through": "~2.3.4",
-    "mimer": "*"
+    "mimer": "*",
+    "sha1": "*"
   },
   "peerDependencies": {
     "browserify": "2.x.x"