0g-chain/x/hard/keeper/repay.go
Denali Marsh 4e6f6d1e9c
Incentive/Hard rebase to master (#773)
* spike: incentive/types

* spike: incentive/types tests

* spike: incentive/types/expected_keepers.go

* spike: incentive/keeper

* spike: incentive/keeper tests

* spike: incentive/sims and incentive/sims tests

* spike: incentive/module

* spike: incentive/module tests

* spike: hard/types

* spike: hard/types hooks

* spike: hard/types

* spike: hard/keeper basics

* spike: hard/keeper hooks

* integrate hard/keeper/borrow.go

* integrate hard/keeper/deposit.go

* integrate hard/keeper/liquidation.go

* integrate hard/keeper/withdraw.go

* integrate hard/keeper/repay.go

* spike: hard/sims

* spike: hard/sims tests

* spike: hard/client

* spike: hard/module

* integrate app.go

* spike: x/hard/keeper compile tests

* incentive/keeper test clean up

* validate usdx incentive types in genesis

* refactoring & fix deposit test

* fix liquidaton tests

* fix incentive tests for hard supply rewards

* fix hard genesis tests

* update incentive genesis state and params

* update cdp rewards accumulation

* update app init order and begin blocker order

Co-authored-by: karzak <kjydavis3@gmail.com>
2021-01-21 14:52:09 +01:00

111 lines
2.9 KiB
Go

package keeper
import (
sdk "github.com/cosmos/cosmos-sdk/types"
sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
"github.com/kava-labs/kava/x/hard/types"
)
// Repay borrowed funds
func (k Keeper) Repay(ctx sdk.Context, sender sdk.AccAddress, coins sdk.Coins) error {
// Get current stored LTV based on stored borrows/deposits
prevLtv, err := k.GetStoreLTV(ctx, sender)
if err != nil {
return err
}
// Check borrow exists here to avoid duplicating store read in ValidateRepay
borrow, found := k.GetBorrow(ctx, sender)
if !found {
return types.ErrBorrowNotFound
}
// Call incentive hook
k.BeforeBorrowModified(ctx, borrow)
// Sync borrow interest so loan is up-to-date
k.SyncBorrowInterest(ctx, sender)
// Validate requested repay
err = k.ValidateRepay(ctx, sender, coins)
if err != nil {
return err
}
payment, err := k.CalculatePaymentAmount(borrow.Amount, coins)
if err != nil {
return err
}
// Sends coins from user to Hard module account
err = k.supplyKeeper.SendCoinsFromAccountToModule(ctx, sender, types.ModuleAccountName, payment)
if err != nil {
return err
}
// Update user's borrow in store
borrow.Amount = borrow.Amount.Sub(payment)
// Calculate the new Loan-to-Value ratio of Deposit-to-Borrow
deposit, foundDeposit := k.GetDeposit(ctx, sender)
if !foundDeposit {
return types.ErrDepositNotFound
}
newLtv, err := k.CalculateLtv(ctx, deposit, borrow)
if err != nil {
return err
}
k.UpdateBorrowAndLtvIndex(ctx, borrow, newLtv, prevLtv)
// Update total borrowed amount
k.DecrementBorrowedCoins(ctx, payment)
// Call incentive hook
if !borrow.Amount.Empty() {
k.AfterBorrowModified(ctx, borrow)
}
ctx.EventManager().EmitEvent(
sdk.NewEvent(
types.EventTypeHardRepay,
sdk.NewAttribute(types.AttributeKeySender, sender.String()),
sdk.NewAttribute(types.AttributeKeyRepayCoins, payment.String()),
),
)
return nil
}
// ValidateRepay validates a requested loan repay
func (k Keeper) ValidateRepay(ctx sdk.Context, sender sdk.AccAddress, coins sdk.Coins) error {
senderAcc := k.accountKeeper.GetAccount(ctx, sender)
senderCoins := senderAcc.SpendableCoins(ctx.BlockTime())
for _, coin := range coins {
if senderCoins.AmountOf(coin.Denom).LT(coin.Amount) {
return sdkerrors.Wrapf(types.ErrInsufficientBalanceForRepay, "account can only repay up to %s%s", senderCoins.AmountOf(coin.Denom), coin.Denom)
}
}
return nil
}
// CalculatePaymentAmount prevents overpayment when repaying borrowed coins
func (k Keeper) CalculatePaymentAmount(owed sdk.Coins, payment sdk.Coins) (sdk.Coins, error) {
repayment := sdk.Coins{}
if !payment.DenomsSubsetOf(owed) {
return repayment, types.ErrInvalidRepaymentDenom
}
for _, coin := range payment {
if coin.Amount.GT(owed.AmountOf(coin.Denom)) {
repayment = append(repayment, sdk.NewCoin(coin.Denom, owed.AmountOf(coin.Denom)))
} else {
repayment = append(repayment, coin)
}
}
return repayment, nil
}