Create yield_farming.py

src/defi/yield_farming.py

@@ -0,0 +1,87 @@
+import time
+from collections import defaultdict
+
+class Token:
+    def __init__(self, name, symbol, total_supply):
+        self.name = name
+        self.symbol = symbol
+        self.total_supply = total_supply
+        self.balances = defaultdict(int)
+
+    def transfer(self, from_address, to_address, amount):
+        if self.balances[from_address] < amount:
+            raise ValueError("Insufficient balance")
+        self.balances[from_address] -= amount
+        self.balances[to_address] += amount
+
+    def mint(self, to_address, amount):
+        self.balances[to_address] += amount
+        self.total_supply += amount
+
+class YieldFarming:
+    def __init__(self, token, reward_token):
+        self.token = token
+        self.reward_token = reward_token
+        self.stakers = {}
+        self.total_staked = 0
+        self.reward_rate = 0.01  # 1% reward per block
+        self.last_update_time = time.time()
+
+    def stake(self, amount, user):
+        if amount <= 0:
+            raise ValueError("Amount must be greater than 0")
+        self.token.transfer(user, self, amount)
+        if user not in self.stakers:
+            self.stakers[user] = {'amount': 0, 'reward_debt': 0}
+        self.stakers[user]['amount'] += amount
+        self.total_staked += amount
+        print(f"{user} has staked {amount} {self.token.symbol}.")
+
+    def withdraw(self, amount, user):
+        if user not in self.stakers or self.stakers[user]['amount'] < amount:
+            raise ValueError("Insufficient staked amount")
+        self.update_rewards(user)
+        self.stakers[user]['amount'] -= amount
+        self.total_staked -= amount
+        self.token.transfer(self, user, amount)
+        print(f"{user} has withdrawn {amount} {self.token.symbol}.")
+
+    def claim_rewards(self, user):
+        self.update_rewards(user)
+        reward = self.stakers[user]['reward_debt']
+        if reward > 0:
+            self.reward_token.mint(user, reward)
+            self.stakers[user]['reward_debt'] = 0
+            print(f"{user} has claimed {reward} {self.reward_token.symbol} as rewards.")
+
+    def update_rewards(self, user):
+        if user in self.stakers:
+            time_passed = time.time() - self.last_update_time
+            reward = (self.stakers[user]['amount'] * self.reward_rate * time_passed)
+            self.stakers[user]['reward_debt'] += reward
+            self.last_update_time = time.time()
+
+# Example usage
+if __name__ == "__main__":
+    # Create tokens
+    token_a = Token("TokenA", "TKA", 1000000)
+    reward_token = Token("RewardToken", "RWT", 1000000)
+
+    # Mint some tokens for the user
+    token_a.mint("user_address", 10000)
+    reward_token.mint("farming_contract", 100000)  # Mint rewards for the contract
+
+    # Create a yield farming contract
+    yield_farming = YieldFarming(token_a, reward_token)
+
+    # User stakes tokens
+    yield_farming.stake(1000, "user_address")
+
+    # Simulate time passing
+    time.sleep(2)  # Simulate 2 seconds passing
+
+    # User claims rewards
+    yield_farming.claim_rewards("user_address")
+
+    # User withdraws staked tokens
+    yield_farming.withdraw(500, "user_address")