feat: buffer for transfer gas

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "mining-cli"
-version = "1.3.4"
+version = "1.3.5"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

src/services/balance_transfer.rs

@@ -21,18 +21,26 @@ pub async fn balance_transfer(
     let signer = get_provider_with_signer(provider, deposit_private_key);
     let deposit_address = get_address_from_private_key(deposit_private_key);
     let balance = provider.get_balance(deposit_address).await?;
-    // todo: use estimate gas
-    let gas_limit = U256::from(10000);
-    let gas_price = U256::from(provider.get_gas_price().await?);
 
-    if balance < gas_price * gas_limit {
+    // Estimate gas and fees to avoid under-budgeting and leave room for gas bumps.
+    let estimate_request = TransactionRequest::default().to(to_address);
+    let estimated_gas = provider.estimate_gas(estimate_request).await?;
+    let fee_estimation = signer.estimate_eip1559_fees().await?;
+    let gas_limit = U256::from(estimated_gas);
+    let max_fee_per_gas = U256::from(fee_estimation.max_fee_per_gas);
+    let gas_budget = gas_limit * max_fee_per_gas * U256::from(2u64);
+
+    if balance <= gas_budget {
         print_warning("Insufficient balance to transfer");
         return Ok(());
     }
-    let transfer_amount = balance - gas_price * gas_limit;
+    let transfer_amount = balance - gas_budget;
     let tx_request = TransactionRequest::default()
         .to(to_address)
-        .value(transfer_amount);
+        .value(transfer_amount)
+        .gas_limit(estimated_gas)
+        .max_fee_per_gas(fee_estimation.max_fee_per_gas)
+        .max_priority_fee_per_gas(fee_estimation.max_priority_fee_per_gas);
     send_transaction_with_gas_bump(
         provider,
         signer,