adding css file generation

index.js

@@ -1,9 +1,38 @@
 'use strict';
 
-var resolveSassPaths = require('./lib/resolve-sass-paths');
+var resolveSassPaths =  require('./lib/resolve-sass-paths')
+ , scss              =  require('./lib/scss')
+ , os                =  require('os')
+ , path              =  require('path')
+ , fs                =  require('fs')
+ ;
 
-exports = module.exports = function (root, cb) {
+var tmpdir = os.tmpDir();
+var genImportsPath = path.join(tmpdir, 'sass-resolve-generated-imports.scss');
 
+/**
+ * Resolves paths to all .scss files from the current package and its dependencies.
+ * The location of these sass files is indicated in the "sass" field inside packags.json.
+ * It then generates the css file including all the rules found in the resolved .scss files.
+ * Additionally it generates a .css.map file to enable sass source maps. 
+ *
+ * NOTE: at this point sass 3.3 is still not officially released, but required to get sourcemaps.
+ * 
+ * @name sassResolve
+ * @function
+ * @param root {String} path to the current package
+ * @param cssFile {String} path at which the resulting css file should be saved, the .css.map file is saved right next to it
+ * @param cb {Function} called back with an error or null when the css file was successfully generated.
+ */
+exports = module.exports = function (root, cssFile, cb) {
+  imports(root, function (err, src) {
+    if (err) return cb(err);
+    // the imports contain absolute paths, so it doesn't matter where the import file ends up
+    fs.writeFile(genImportsPath, src, 'utf8', function (err) {
+      if (err) return cb(err);
+      scss(genImportsPath, cssFile, cb);
+    });
+  });  
 }
 
 /**
@@ -26,7 +55,7 @@ exports.paths = resolveSassPaths;
  * @param root {String} full path to the project whose sass files to resolve
  * @param cb {Function} called back with imports for the .scss files or an error if one occurred
  */
-exports.imports = function (root, cb) {
+var imports = exports.imports = function (root, cb) {
   resolveSassPaths(root, function (err, scssFiles) {
     if (err) return cb(err);
     var imports = scssFiles.map(function (f) {
@@ -37,3 +66,15 @@ exports.imports = function (root, cb) {
   });
 }
 
+// Test
+if (!module.parent) {
+  var cssFile = path.join(__dirname, 'test', 'fixtures', 'imports.css');
+  exports(
+      path.join(__dirname, 'test', 'fixtures')
+    , cssFile 
+    , function (err) {
+        if (err) return console.error(err);
+        var css = fs.readFileSync(cssFile, 'utf8');
+        console.log(css);
+      });
+}