From 82165d4c57773f2568c606d557728b972dc75b64 Mon Sep 17 00:00:00 2001
From: Daniel De Castro <daniel.decastro@firstdigitalfinance.com>
Date: Thu, 5 Nov 2020 22:12:59 +0800
Subject: [PATCH 1/2] feat: add display method, refactor

---
 blockchain.py | 67 ++++++++++++++++++++++++++++++++-------------------
 1 file changed, 42 insertions(+), 25 deletions(-)

diff --git a/blockchain.py b/blockchain.py
index 7a51b9d..90a13fa 100644
--- a/blockchain.py
+++ b/blockchain.py
@@ -1,14 +1,14 @@
-import datetime
+from datetime import datetime
 import hashlib
 
 class Block:
-    blockNo = 0
+    block_no = 0
     data = None
     next = None
     hash = None
     nonce = 0
     previous_hash = 0x0
-    timestamp = datetime.datetime.now()
+    timestamp = datetime.now()
 
     def __init__(self, data):
         self.data = data
@@ -16,48 +16,65 @@ def __init__(self, data):
     def hash(self):
         h = hashlib.sha256()
         h.update(
-        str(self.nonce).encode('utf-8') +
-        str(self.data).encode('utf-8') +
-        str(self.previous_hash).encode('utf-8') +
-        str(self.timestamp).encode('utf-8') +
-        str(self.blockNo).encode('utf-8')
+            str(self.nonce).encode('utf-8') +
+            str(self.data).encode('utf-8') +
+            str(self.previous_hash).encode('utf-8') +
+            str(self.timestamp).encode('utf-8') +
+            str(self.block_no).encode('utf-8')
         )
         return h.hexdigest()
 
-    def __str__(self):
-        return "Block Hash: " + str(self.hash()) + "\nBlockNo: " + str(self.blockNo) + "\nBlock Data: " + str(self.data) + "\nHashes: " + str(self.nonce) + "\n--------------"
+    def __repr__(self):
+        return (
+            f'Block Hash: {str(self.hash())}\n'
+            f'Block #: {self.block_no}\n'
+            f'Block Data: {self.data}\n'
+            f'Hashes: {self.nonce}\n'
+        )
 
-class Blockchain:
 
-    diff = 20
-    maxNonce = 2**32
-    target = 2 ** (256-diff)
+class Blockchain:
+    difficulty = 10
+    max_nonce = 2**32
+    target = 2 ** (256-difficulty)
 
     block = Block("Genesis")
     dummy = head = block
 
     def add(self, block):
-
         block.previous_hash = self.block.hash()
-        block.blockNo = self.block.blockNo + 1
-
+        block.block_no = self.block.block_no + 1
         self.block.next = block
         self.block = self.block.next
 
     def mine(self, block):
-        for n in range(self.maxNonce):
+        for _ in range(self.max_nonce):
             if int(block.hash(), 16) <= self.target:
                 self.add(block)
-                print(block)
                 break
             else:
                 block.nonce += 1
+    
+    def show(self):
+        if not self.head:
+            self.head = self.block
+        while self.head:
+            print(self.head)
+            self.head = self.head.next
+        
 
-blockchain = Blockchain()
+def _main():
+    blockchain = Blockchain()
+    # miningg
+    for n in range(10):
+        blockchain.mine(Block(f"Block {n+1}"))
+        blockchain.show()
+    #adding
+    blockchain.add(Block('added block'))
+    blockchain.show()
+    blockchain.add(Block('added block2'))
+    blockchain.show()
 
-for n in range(10):
-    blockchain.mine(Block("Block " + str(n+1)))
 
-while blockchain.head != None:
-    print(blockchain.head)
-    blockchain.head = blockchain.head.next
+if __name__ == "__main__":
+    _main()

From c0ddb0640a979d983af6335ceb65b41244e03a2d Mon Sep 17 00:00:00 2001
From: Daniel De Castro <daniel.decastro@firstdigitalfinance.com>
Date: Thu, 5 Nov 2020 22:13:52 +0800
Subject: [PATCH 2/2] style: remove whitespace

---
 blockchain.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/blockchain.py b/blockchain.py
index 90a13fa..f77b7ba 100644
--- a/blockchain.py
+++ b/blockchain.py
@@ -54,14 +54,14 @@ def mine(self, block):
                 break
             else:
                 block.nonce += 1
-    
+
     def show(self):
         if not self.head:
             self.head = self.block
         while self.head:
             print(self.head)
             self.head = self.head.next
-        
+
 
 def _main():
     blockchain = Blockchain()