[ Bug ] [ Fees ] Agent fees is paid by agent and not the user.

Allen-Muhani commented 2 years ago

What is happening:

Agent accepts the request
Amount stated PLUS the agent fee (5 cents) is withdrawn from agents wallet and sent to escrow (5 cents too many).
After both, user and agent, confirm the M-PESA Payment, the 0.05 cUSD agent fee is sent back from the Wakala escrow contract to the agent wallet.
Meaning: The agent first pays too much, then gets it back. And he does not earn anything.

What should happen:

Agent accepts request
Amount stated (not plus the agent fee) is withdrawn from agents wallet and sent to the escrow contract.
both, agent and user, confirm M-PESA payment.
amount from escrow is sent to users wallet.
there is no explicit payment of 0.05 cUSD

Scenario 1: User Request cUSD Top up.

User posts request of 500 KSH
Fee for user = 0.05 cUSD (agent fee) + 0.04 cUSD (Wakala fee) = 0.09 cUSD
Amount the user will receive = (500 / 115) cUSD - 0.09 cUSD = 4.35 cUSD - 0.09 cUSD = 4.26 cUSD
Agent accepts request
money withdrawn from agent wallet to escrow = 4.26 cUSD (separate transaction: wallet to escrow contract)
money withdrawn from agent wallet to Kukuza treasury = 0.04 cUSD (separate transaction: wallet to kukuza treasury
Total withdrawn: 4.30 cUSD
4.30 cUSD is 5 cents less than 4.35 cUSD (500 / 115), because the agent retains the 5 cent agent fee

Scenario 2: User Requests cUSD Withdrawal

Agent accepts request
Agent receives: (500 / 115)- Wakala fee = 4.35 - 0.04 = 4.31 cUSD
Agent sends via M-PESA: 4.35 cUSD - wakala fee - agent fee = 500 KSH - 0.09 cUSD = 500 KSH - 10.35 KSH = 489.65 KSH
User post request to withdraw 500 KSH
Fee for user = 0.05 cUSD (agent fee) + 0.04 cUSD (Wakala fee) = 0.09 cUSD
amount withdrawn from user wallet to escrow: (500/115) - wakala fee = 4.35 - 0.04 = 4.31 cUSD
amount withdrawn from user wallet to treasury: 0.04 cUSD Wakala fee
Check: total withdrawn: 4.35 cUSD
M-PESA amount the user will receive: (500 / 115) cUSD - 0.09 cUSD = 4.35 cUSD - 0.09 cUSD = 4.26 cUSD

4.26 * 115 = 489.9

Allen-Muhani commented 2 years ago

@steffenkrogmann Implementation on the smart contract is done and tested

Allen-Muhani commented 2 years ago

Kukuza / sargo-smart-contracts