Change parsing format to use AST via RedBaron

Moved away from using manual parsing. Source is parsed using RedBaron to make the FST. Some import formats not yet implemented, and still some bugs to work out. However, the current script works well for the two cases in the file comments.

scripts/flaskext_migrate.py

@@ -5,10 +5,41 @@ from redbaron import RedBaron
 import sys
 
 
-with open("test.py", "r") as source_code:
-    red = RedBaron(source_code.read())
+def read_source(input_file):
+    with open(input_file, "r") as source_code:
+        red = RedBaron(source_code.read())
+    return red
 
-print red.dumps()
 
-# with open("code.py", "w") as source_code:
-#     source_code.write(red.dumps())
+def write_source(red, input_file):
+    with open(input_file, "w") as source_code:
+        source_code.write(red.dumps())
+
+
+def fix_imports(red):
+    from_imports = red.find_all("FromImport")
+    for x in range(len(from_imports)):
+        values = from_imports[x].value
+        if (values[0].value == 'flask') and (values[1].value == 'ext'):
+            # Case 1
+            if len(from_imports[x].value) == 3:
+                package = values[2].value
+                modules = from_imports[x].modules()
+                r = "{}," * len(modules)
+                print modules
+                from_imports[x].replace("from flask_%s import %s"
+                                        % (package, r.format(*modules)[:-1]))
+            # Case 2
+            else:
+                module = from_imports[x].modules()[0]
+                from_imports[x].replace("import flask_%s as %s"
+                                        % (module, module))
+
+    return red
+
+
+if __name__ == "__main__":
+    input_file = sys.argv[1]
+    ast = read_source(input_file)
+    new_ast = fix_imports(ast)
+    write_source(new_ast, input_file)