From d8838b67f83897a074bc910cc7acc413faeb565c Mon Sep 17 00:00:00 2001
From: Jason Lai <jasonlai256@gmail.com>
Date: Tue, 9 Oct 2012 22:38:17 +0800
Subject: [PATCH] dev the handler module continuing.

---
 pypw/handler.py | 63 ++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 55 insertions(+), 8 deletions(-)

diff --git a/pypw/handler.py b/pypw/handler.py
index 9e85f5f..f8b076c 100644
--- a/pypw/handler.py
+++ b/pypw/handler.py
@@ -13,7 +13,9 @@
 from Crypto import Random
 
 import os
+import json
 import logging
+import hashlib
 
 
 class Handler(object):
@@ -24,11 +26,16 @@ class Handler(object):
     def __init__(self):
         # Initialize Log
         self.log = logging.getLogger('pypw')
+        # Initialize the attributes of class
+        self.initialized = False
         self.filepath = ''
+        self.data = None
 
     def initialize(self, cipher, filepath=None):
         """
         validate the cipher and load the data from outside file.
+
+        :return: True if successfully initialize, else will be False
         """
         raise NotImplementedError
 
@@ -38,26 +45,66 @@ def write(self):
         """
         raise NotImplementedError
 
-    def add_item(group, item, value, update=False):
+    def add_record(group, record, value, update=False):
         raise NotImplementedError
 
     @property
-    def items(self):
+    def records(self):
         raise NotImplementedError
 
+    @classmethod
+    def figure_32Byte_key(cls, text):
+        sha = hashlib.sha256()
+        sha.update(text)
+        return sha.hexdigest()[::2]
+
 
 class AESHandler(Handler):
     """
     Hander use AES to encrypt/decrypt user infomations
     """
 
-    def __init__(self):
-        self.key = b''
+    def __init__(self):        
+        self.cipher = ''
+        self.data = None
+        super(AESHandler, self).__init__()
 
     def initialize(self, cipher, filepath='records.dat'):
-        if not os.path.existx(filepath):
-            self._init_struct()
-            return
+        self.filepath = filepath
+        self.cipher = self.figure_32Byte_key(cipher)
+        
+        # first initial the program
+        if not os.path.existx(self.filepath):
+            self._initial_data()
+            self.initialized = True
+            return self.initialized
+
+        # validate the cipher and load the data
+        with open(filepath, 'rb') as f:
+            ciphertext = f.read()
+        jsondata = self.decrypt(ciphertext, key)
+        try:
+            self.data = json.loads(jsondata)
+        except ValueError:
+            return self.initialized
+
+        if self.data['digest'] == self.cipher:
+            self.initialized = True
+
+        return self.initialized
+
+    def _initial_data(self):
+        pass
+
+    def write(self):
+        pass
+
+    def add_record(group, record, value, update=False):
+        pass
+
+    @property
+    def records(self):
+        pass
 
     @classmethod
     def encrypt(cls, plaintext, key):
@@ -71,4 +118,4 @@ def decrypt(cls, ciphertext, key):
         iv = Random.new().read(AES.block_size)
         cipher = AES.new(key, AES.MODE_CFB, iv)
         return cipher.decrypt(ciphertext)[AES.block_size:]
-        
+