package keeper import ( "fmt" "time" sdk "github.com/cosmos/cosmos-sdk/types" "github.com/cosmos/cosmos-sdk/x/supply" "github.com/kava-labs/kava/x/auction/types" ) // StartSurplusAuction starts a new surplus (forward) auction. func (k Keeper) StartSurplusAuction(ctx sdk.Context, seller string, lot sdk.Coin, bidDenom string) (uint64, sdk.Error) { auction := types.NewSurplusAuction( seller, lot, bidDenom, ctx.BlockTime().Add(k.GetParams(ctx).MaxAuctionDuration)) err := k.supplyKeeper.SendCoinsFromModuleToModule(ctx, seller, types.ModuleName, sdk.NewCoins(lot)) if err != nil { return 0, err } auctionID, err := k.StoreNewAuction(ctx, auction) if err != nil { return 0, err } return auctionID, nil } // StartDebtAuction starts a new debt (reverse) auction. func (k Keeper) StartDebtAuction(ctx sdk.Context, buyer string, bid sdk.Coin, initialLot sdk.Coin) (uint64, sdk.Error) { auction := types.NewDebtAuction( buyer, bid, initialLot, ctx.BlockTime().Add(k.GetParams(ctx).MaxAuctionDuration)) // This auction type mints coins at close. Need to check module account has minting privileges to avoid potential err in endblocker. macc := k.supplyKeeper.GetModuleAccount(ctx, buyer) if !macc.HasPermission(supply.Minter) { return 0, sdk.ErrInternal("module does not have minting permissions") } auctionID, err := k.StoreNewAuction(ctx, auction) if err != nil { return 0, err } return auctionID, nil } // StartCollateralAuction starts a new collateral (2-phase) auction. func (k Keeper) StartCollateralAuction(ctx sdk.Context, seller string, lot sdk.Coin, maxBid sdk.Coin, lotReturnAddrs []sdk.AccAddress, lotReturnWeights []sdk.Int) (uint64, sdk.Error) { weightedAddresses, err := types.NewWeightedAddresses(lotReturnAddrs, lotReturnWeights) if err != nil { return 0, err } auction := types.NewCollateralAuction(seller, lot, ctx.BlockTime().Add(types.DefaultMaxAuctionDuration), maxBid, weightedAddresses) err = k.supplyKeeper.SendCoinsFromModuleToModule(ctx, seller, types.ModuleName, sdk.NewCoins(lot)) if err != nil { return 0, err } auctionID, err := k.StoreNewAuction(ctx, auction) if err != nil { return 0, err } return auctionID, nil } // PlaceBid places a bid on any auction. func (k Keeper) PlaceBid(ctx sdk.Context, auctionID uint64, bidder sdk.AccAddress, newAmount sdk.Coin) sdk.Error { auction, found := k.GetAuction(ctx, auctionID) if !found { return sdk.ErrInternal("auction doesn't exist") } // validation common to all auctions if ctx.BlockTime().After(auction.GetEndTime()) { return sdk.ErrInternal("auction has closed") } // move coins and return updated auction var err sdk.Error var updatedAuction types.Auction switch a := auction.(type) { case types.SurplusAuction: if updatedAuction, err = k.PlaceBidSurplus(ctx, a, bidder, newAmount); err != nil { return err } case types.DebtAuction: if updatedAuction, err = k.PlaceBidDebt(ctx, a, bidder, newAmount); err != nil { return err } case types.CollateralAuction: if !a.IsReversePhase() { updatedAuction, err = k.PlaceForwardBidCollateral(ctx, a, bidder, newAmount) } else { updatedAuction, err = k.PlaceReverseBidCollateral(ctx, a, bidder, newAmount) } if err != nil { return err } default: panic(fmt.Sprintf("unrecognized auction type: %T", auction)) } k.SetAuction(ctx, updatedAuction) return nil } // PlaceBidSurplus places a forward bid on a surplus auction, moving coins and returning the updated auction. func (k Keeper) PlaceBidSurplus(ctx sdk.Context, a types.SurplusAuction, bidder sdk.AccAddress, bid sdk.Coin) (types.SurplusAuction, sdk.Error) { // Validate new bid if bid.Denom != a.Bid.Denom { return a, sdk.ErrInternal("bid denom doesn't match auction") } if !a.Bid.IsLT(bid) { return a, sdk.ErrInternal("bid not greater than last bid") } // New bidder pays back old bidder // Catch edge cases of a bidder replacing their own bid, and the amount being zero (sending zero coins produces meaningless send events). if !bidder.Equals(a.Bidder) && !a.Bid.IsZero() { err := k.supplyKeeper.SendCoinsFromAccountToModule(ctx, bidder, types.ModuleName, sdk.NewCoins(a.Bid)) if err != nil { return a, err } err = k.supplyKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, a.Bidder, sdk.NewCoins(a.Bid)) if err != nil { return a, err } } // Increase in bid is burned err := k.supplyKeeper.SendCoinsFromAccountToModule(ctx, bidder, a.Initiator, sdk.NewCoins(bid.Sub(a.Bid))) if err != nil { return a, err } err = k.supplyKeeper.BurnCoins(ctx, a.Initiator, sdk.NewCoins(bid.Sub(a.Bid))) if err != nil { return a, err } // Update Auction a.Bidder = bidder a.Bid = bid a.EndTime = earliestTime(ctx.BlockTime().Add(k.GetParams(ctx).BidDuration), a.MaxEndTime) // increment timeout return a, nil } // PlaceForwardBidCollateral places a forward bid on a collateral auction, moving coins and returning the updated auction. func (k Keeper) PlaceForwardBidCollateral(ctx sdk.Context, a types.CollateralAuction, bidder sdk.AccAddress, bid sdk.Coin) (types.CollateralAuction, sdk.Error) { // Validate new bid if bid.Denom != a.Bid.Denom { return a, sdk.ErrInternal("bid denom doesn't match auction") } if a.IsReversePhase() { return a, sdk.ErrInternal("auction is not in forward phase") } if !a.Bid.IsLT(bid) { return a, sdk.ErrInternal("auction in forward phase, new bid not higher than last bid") } if a.MaxBid.IsLT(bid) { return a, sdk.ErrInternal("bid higher than max bid") } // New bidder pays back old bidder // Catch edge cases of a bidder replacing their own bid, and the amount being zero (sending zero coins produces meaningless send events). if !bidder.Equals(a.Bidder) && !a.Bid.IsZero() { err := k.supplyKeeper.SendCoinsFromAccountToModule(ctx, bidder, types.ModuleName, sdk.NewCoins(a.Bid)) if err != nil { return a, err } err = k.supplyKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, a.Bidder, sdk.NewCoins(a.Bid)) if err != nil { return a, err } } // Increase in bid sent to auction initiator err := k.supplyKeeper.SendCoinsFromAccountToModule(ctx, bidder, a.Initiator, sdk.NewCoins(bid.Sub(a.Bid))) if err != nil { return a, err } // Update Auction a.Bidder = bidder a.Bid = bid a.EndTime = earliestTime(ctx.BlockTime().Add(k.GetParams(ctx).BidDuration), a.MaxEndTime) // increment timeout return a, nil } // PlaceReverseBidCollateral places a reverse bid on a collateral auction, moving coins and returning the updated auction. func (k Keeper) PlaceReverseBidCollateral(ctx sdk.Context, a types.CollateralAuction, bidder sdk.AccAddress, lot sdk.Coin) (types.CollateralAuction, sdk.Error) { // Validate new bid if lot.Denom != a.Lot.Denom { return a, sdk.ErrInternal("lot denom doesn't match auction") } if !a.IsReversePhase() { return a, sdk.ErrInternal("auction not in reverse phase") } if lot.IsNegative() { return a, sdk.ErrInternal("can't bid negative amount") } if !lot.IsLT(a.Lot) { return a, sdk.ErrInternal("auction in reverse phase, new bid not less than previous amount") } // New bidder pays back old bidder // Catch edge cases of a bidder replacing their own bid if !bidder.Equals(a.Bidder) { err := k.supplyKeeper.SendCoinsFromAccountToModule(ctx, bidder, types.ModuleName, sdk.NewCoins(a.Bid)) if err != nil { return a, err } err = k.supplyKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, a.Bidder, sdk.NewCoins(a.Bid)) if err != nil { return a, err } } // Decrease in lot is sent to weighted addresses (normally the CDP depositors) // TODO paying out rateably to cdp depositors is vulnerable to errors compounding over multiple bids - check this can't be gamed. lotPayouts, err := splitCoinIntoWeightedBuckets(a.Lot.Sub(lot), a.LotReturns.Weights) if err != nil { return a, err } for i, payout := range lotPayouts { err = k.supplyKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, a.LotReturns.Addresses[i], sdk.NewCoins(payout)) if err != nil { return a, err } } // Update Auction a.Bidder = bidder a.Lot = lot a.EndTime = earliestTime(ctx.BlockTime().Add(k.GetParams(ctx).BidDuration), a.MaxEndTime) // increment timeout return a, nil } // PlaceBidDebt places a reverse bid on a debt auction, moving coins and returning the updated auction. func (k Keeper) PlaceBidDebt(ctx sdk.Context, a types.DebtAuction, bidder sdk.AccAddress, lot sdk.Coin) (types.DebtAuction, sdk.Error) { // Validate new bid if lot.Denom != a.Lot.Denom { return a, sdk.ErrInternal("lot denom doesn't match auction") } if lot.IsNegative() { return a, sdk.ErrInternal("lot less than 0") } if !lot.IsLT(a.Lot) { return a, sdk.ErrInternal("lot not smaller than last lot") } // New bidder pays back old bidder // Catch edge cases of a bidder replacing their own bid if !bidder.Equals(a.Bidder) { err := k.supplyKeeper.SendCoinsFromAccountToModule(ctx, bidder, types.ModuleName, sdk.NewCoins(a.Bid)) if err != nil { return a, err } err = k.supplyKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, a.Bidder, sdk.NewCoins(a.Bid)) if err != nil { return a, err } } // Update Auction a.Bidder = bidder a.Lot = lot a.EndTime = earliestTime(ctx.BlockTime().Add(k.GetParams(ctx).BidDuration), a.MaxEndTime) // increment timeout return a, nil } // CloseAuction closes an auction and distributes funds to the highest bidder. func (k Keeper) CloseAuction(ctx sdk.Context, auctionID uint64) sdk.Error { auction, found := k.GetAuction(ctx, auctionID) if !found { return sdk.ErrInternal("auction doesn't exist") } if ctx.BlockTime().Before(auction.GetEndTime()) { return sdk.ErrInternal(fmt.Sprintf("auction can't be closed as curent block time (%v) is under auction end time (%v)", ctx.BlockTime(), auction.GetEndTime())) } // payout to the last bidder switch auc := auction.(type) { case types.SurplusAuction: if err := k.PayoutSurplusAuction(ctx, auc); err != nil { return err } case types.DebtAuction: if err := k.PayoutDebtAuction(ctx, auc); err != nil { return err } case types.CollateralAuction: if err := k.PayoutCollateralAuction(ctx, auc); err != nil { return err } default: panic("unrecognized auction type") } k.DeleteAuction(ctx, auctionID) return nil } // PayoutDebtAuction pays out the proceeds for a debt auction, first minting the coins. func (k Keeper) PayoutDebtAuction(ctx sdk.Context, a types.DebtAuction) sdk.Error { err := k.supplyKeeper.MintCoins(ctx, a.Initiator, sdk.NewCoins(a.Lot)) if err != nil { return err } err = k.supplyKeeper.SendCoinsFromModuleToAccount(ctx, a.Initiator, a.Bidder, sdk.NewCoins(a.Lot)) if err != nil { return err } return nil } // PayoutSurplusAuction pays out the proceeds for a surplus auction. func (k Keeper) PayoutSurplusAuction(ctx sdk.Context, a types.SurplusAuction) sdk.Error { err := k.supplyKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, a.Bidder, sdk.NewCoins(a.Lot)) if err != nil { return err } return nil } // PayoutCollateralAuction pays out the proceeds for a collateral auction. func (k Keeper) PayoutCollateralAuction(ctx sdk.Context, a types.CollateralAuction) sdk.Error { err := k.supplyKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, a.Bidder, sdk.NewCoins(a.Lot)) if err != nil { return err } return nil } // CloseExpiredAuctions finds all auctions that are past (or at) their ending times and closes them, paying out to the highest bidder. func (k Keeper) CloseExpiredAuctions(ctx sdk.Context) sdk.Error { var expiredAuctions []uint64 k.IterateAuctionsByTime(ctx, ctx.BlockTime(), func(id uint64) bool { expiredAuctions = append(expiredAuctions, id) return false }) // Note: iteration and auction closing are in separate loops as db should not be modified during iteration // TODO is this correct? gov modifies during iteration for _, id := range expiredAuctions { if err := k.CloseAuction(ctx, id); err != nil { return err } } return nil } // earliestTime returns the earliest of two times. func earliestTime(t1, t2 time.Time) time.Time { if t1.Before(t2) { return t1 } else { return t2 // also returned if times are equal } } // splitCoinIntoWeightedBuckets divides up some amount of coins according to some weights. func splitCoinIntoWeightedBuckets(coin sdk.Coin, buckets []sdk.Int) ([]sdk.Coin, sdk.Error) { for _, bucket := range buckets { if bucket.IsNegative() { return nil, sdk.ErrInternal("cannot split coin into bucket with negative weight") } } amounts := splitIntIntoWeightedBuckets(coin.Amount, buckets) result := make([]sdk.Coin, len(amounts)) for i, a := range amounts { result[i] = sdk.NewCoin(coin.Denom, a) } return result, nil }