How to call gnosis-safe's changeThresold function from onchain contract which is owner of that safe

Question

I have one safe wallet and it's owner is one smart contract. I want to call safe transaction to this method changeThreshold by that owner contract ? One way i found is using execTransaction method because changeThreshold can be called only by safeTransactions.

1. So is this correct way ?
2. How to construct and this transactions including signature from it's owner contract(and all this should be done onchain).
3. How can i calculate gas related parameters like safeTxGas & baseGas inside owner contract ?

Answer 1

Hey if the owner is smart contract ensure that it supports eip-1271. When submitting txn should be called from the owner smart contract where toAddress -> safe, calldata -> execTransaction method. Incase of safeTxGas, baseGas parameters can be 0.