contract WithdrawalContract

state = { .richest  : Address = 0,
          .mostSent : Uint    = 0,
          .pendingWithdrawals : Map Address => Uint = [] }

fun becomeRichest() returns (Bool) =
    if (@call.value > @state.mostSent) then
        let totalAmount:Uint = pendingWithdrawals[@state.richest] + @call.value in
            {.state = @state[ .pendingWithdrawals = @state.pendingWithdrawals[@state.richest] = @call.value,
                             .richest = @call.sender,
                             .mostSent = @call.value],
             .return = true}
     else
         {.return = false}


fun withdraw()
    let amount:Uint = @state.pendingWithdrawals[@call.sender] in
        { .state = @state[ @state.pendingWithdrawals[@call.sender] = 0],
          .transactions = spend_tx(amount, @call.sender)
        }