package keeper

import (
	"github.com/cosmos/cosmos-sdk/client"
	"github.com/cosmos/cosmos-sdk/codec"
	sdk "github.com/cosmos/cosmos-sdk/types"
	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
	supplyexported "github.com/cosmos/cosmos-sdk/x/supply/exported"

	abci "github.com/tendermint/tendermint/abci/types"

	"github.com/kava-labs/kava/x/hard/types"
)

// NewQuerier is the module level router for state queries
func NewQuerier(k Keeper) sdk.Querier {
	return func(ctx sdk.Context, path []string, req abci.RequestQuery) (res []byte, err error) {
		switch path[0] {
		case types.QueryGetParams:
			return queryGetParams(ctx, req, k)
		case types.QueryGetModuleAccounts:
			return queryGetModAccounts(ctx, req, k)
		case types.QueryGetDeposits:
			return queryGetDeposits(ctx, req, k)
		case types.QueryGetUnsyncedDeposits:
			return queryGetUnsyncedDeposits(ctx, req, k)
		case types.QueryGetTotalDeposited:
			return queryGetTotalDeposited(ctx, req, k)
		case types.QueryGetBorrows:
			return queryGetBorrows(ctx, req, k)
		case types.QueryGetUnsyncedBorrows:
			return queryGetUnsyncedBorrows(ctx, req, k)
		case types.QueryGetTotalBorrowed:
			return queryGetTotalBorrowed(ctx, req, k)
		case types.QueryGetInterestRate:
			return queryGetInterestRate(ctx, req, k)
		case types.QueryGetReserves:
			return queryGetReserves(ctx, req, k)
		case types.QueryGetInterestFactors:
			return queryGetInterestFactors(ctx, req, k)
		default:
			return nil, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "unknown %s query endpoint", types.ModuleName)
		}
	}
}

func queryGetParams(ctx sdk.Context, _ abci.RequestQuery, k Keeper) ([]byte, error) {
	// Get params
	params := k.GetParams(ctx)

	// Encode results
	bz, err := codec.MarshalJSONIndent(k.cdc, params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}
	return bz, nil
}

func queryGetModAccounts(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {

	var params types.QueryAccountParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}
	var accs []supplyexported.ModuleAccountI
	if len(params.Name) > 0 {
		acc := k.supplyKeeper.GetModuleAccount(ctx, params.Name)
		accs = append(accs, acc)
	} else {
		acc := k.supplyKeeper.GetModuleAccount(ctx, types.ModuleAccountName)
		accs = append(accs, acc)
	}

	bz, err := codec.MarshalJSONIndent(k.cdc, accs)

	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}

	return bz, nil
}

func queryGetDeposits(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {

	var params types.QueryDepositsParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}
	denom := len(params.Denom) > 0
	owner := len(params.Owner) > 0

	var deposits types.Deposits
	switch {
	case owner && denom:
		deposit, found := k.GetSyncedDeposit(ctx, params.Owner)
		if found {
			for _, coin := range deposit.Amount {
				if coin.Denom == params.Denom {
					deposits = append(deposits, deposit)
				}
			}
		}
	case owner:
		deposit, found := k.GetSyncedDeposit(ctx, params.Owner)
		if found {
			deposits = append(deposits, deposit)
		}
	case denom:
		k.IterateDeposits(ctx, func(deposit types.Deposit) (stop bool) {
			if deposit.Amount.AmountOf(params.Denom).IsPositive() {
				deposits = append(deposits, deposit)
			}
			return false
		})
	default:
		k.IterateDeposits(ctx, func(deposit types.Deposit) (stop bool) {
			deposits = append(deposits, deposit)
			return false
		})
	}

	var bz []byte

	// If owner param was specified then deposits array already contains the user's synced deposit
	if owner {
		bz, err = codec.MarshalJSONIndent(types.ModuleCdc, deposits)
		if err != nil {
			return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
		}
		return bz, nil
	}

	// Otherwise we need to simulate syncing of each deposit
	var syncedDeposits types.Deposits
	for _, deposit := range deposits {
		syncedDeposit, _ := k.GetSyncedDeposit(ctx, deposit.Depositor)
		syncedDeposits = append(syncedDeposits, syncedDeposit)
	}

	start, end := client.Paginate(len(syncedDeposits), params.Page, params.Limit, 100)
	if start < 0 || end < 0 {
		syncedDeposits = types.Deposits{}
	} else {
		syncedDeposits = syncedDeposits[start:end]
	}

	bz, err = codec.MarshalJSONIndent(types.ModuleCdc, syncedDeposits)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}
	return bz, nil
}

func queryGetUnsyncedDeposits(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {

	var params types.QueryUnsyncedDepositsParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}
	denom := len(params.Denom) > 0
	owner := len(params.Owner) > 0

	var deposits types.Deposits
	switch {
	case owner && denom:
		deposit, found := k.GetDeposit(ctx, params.Owner)
		if found {
			for _, coin := range deposit.Amount {
				if coin.Denom == params.Denom {
					deposits = append(deposits, deposit)
				}
			}
		}
	case owner:
		deposit, found := k.GetDeposit(ctx, params.Owner)
		if found {
			deposits = append(deposits, deposit)
		}
	case denom:
		k.IterateDeposits(ctx, func(deposit types.Deposit) (stop bool) {
			if deposit.Amount.AmountOf(params.Denom).IsPositive() {
				deposits = append(deposits, deposit)
			}
			return false
		})
	default:
		k.IterateDeposits(ctx, func(deposit types.Deposit) (stop bool) {
			deposits = append(deposits, deposit)
			return false
		})
	}

	var bz []byte

	start, end := client.Paginate(len(deposits), params.Page, params.Limit, 100)
	if start < 0 || end < 0 {
		deposits = types.Deposits{}
	} else {
		deposits = deposits[start:end]
	}

	bz, err = codec.MarshalJSONIndent(types.ModuleCdc, deposits)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}
	return bz, nil
}

func queryGetBorrows(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {

	var params types.QueryBorrowsParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}
	denom := len(params.Denom) > 0
	owner := len(params.Owner) > 0

	var borrows types.Borrows
	switch {
	case owner && denom:
		borrow, found := k.GetSyncedBorrow(ctx, params.Owner)
		if found {
			for _, coin := range borrow.Amount {
				if coin.Denom == params.Denom {
					borrows = append(borrows, borrow)
				}
			}
		}
	case owner:
		borrow, found := k.GetSyncedBorrow(ctx, params.Owner)
		if found {
			borrows = append(borrows, borrow)
		}
	case denom:
		k.IterateBorrows(ctx, func(borrow types.Borrow) (stop bool) {
			if borrow.Amount.AmountOf(params.Denom).IsPositive() {
				borrows = append(borrows, borrow)
			}
			return false
		})
	default:
		k.IterateBorrows(ctx, func(borrow types.Borrow) (stop bool) {
			borrows = append(borrows, borrow)
			return false
		})
	}

	var bz []byte

	// If owner param was specified then borrows array already contains the user's synced borrow
	if owner {
		bz, err = codec.MarshalJSONIndent(types.ModuleCdc, borrows)
		if err != nil {
			return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
		}
		return bz, nil
	}

	// Otherwise we need to simulate syncing of each borrow
	var syncedBorrows types.Borrows
	for _, borrow := range borrows {
		syncedBorrow, _ := k.GetSyncedBorrow(ctx, borrow.Borrower)
		syncedBorrows = append(syncedBorrows, syncedBorrow)
	}

	start, end := client.Paginate(len(syncedBorrows), params.Page, params.Limit, 100)
	if start < 0 || end < 0 {
		syncedBorrows = types.Borrows{}
	} else {
		syncedBorrows = syncedBorrows[start:end]
	}

	bz, err = codec.MarshalJSONIndent(types.ModuleCdc, syncedBorrows)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}
	return bz, nil
}

func queryGetUnsyncedBorrows(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {

	var params types.QueryUnsyncedBorrowsParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}
	denom := len(params.Denom) > 0
	owner := len(params.Owner) > 0

	var borrows types.Borrows
	switch {
	case owner && denom:
		borrow, found := k.GetBorrow(ctx, params.Owner)
		if found {
			for _, coin := range borrow.Amount {
				if coin.Denom == params.Denom {
					borrows = append(borrows, borrow)
				}
			}
		}
	case owner:
		borrow, found := k.GetBorrow(ctx, params.Owner)
		if found {
			borrows = append(borrows, borrow)
		}
	case denom:
		k.IterateBorrows(ctx, func(borrow types.Borrow) (stop bool) {
			if borrow.Amount.AmountOf(params.Denom).IsPositive() {
				borrows = append(borrows, borrow)
			}
			return false
		})
	default:
		k.IterateBorrows(ctx, func(borrow types.Borrow) (stop bool) {
			borrows = append(borrows, borrow)
			return false
		})
	}

	var bz []byte

	start, end := client.Paginate(len(borrows), params.Page, params.Limit, 100)
	if start < 0 || end < 0 {
		borrows = types.Borrows{}
	} else {
		borrows = borrows[start:end]
	}

	bz, err = codec.MarshalJSONIndent(types.ModuleCdc, borrows)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}
	return bz, nil
}

func queryGetTotalBorrowed(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {
	var params types.QueryTotalBorrowedParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}

	borrowedCoins, found := k.GetBorrowedCoins(ctx)
	if !found {
		return nil, types.ErrBorrowedCoinsNotFound
	}

	// If user specified a denom only return coins of that denom type
	if len(params.Denom) > 0 {
		borrowedCoins = sdk.NewCoins(sdk.NewCoin(params.Denom, borrowedCoins.AmountOf(params.Denom)))
	}

	bz, err := codec.MarshalJSONIndent(types.ModuleCdc, borrowedCoins)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}

	return bz, nil
}

func queryGetTotalDeposited(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {
	var params types.QueryTotalDepositedParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}

	suppliedCoins, found := k.GetSuppliedCoins(ctx)
	if !found {
		return nil, types.ErrSuppliedCoinsNotFound
	}

	// If user specified a denom only return coins of that denom type
	if len(params.Denom) > 0 {
		suppliedCoins = sdk.NewCoins(sdk.NewCoin(params.Denom, suppliedCoins.AmountOf(params.Denom)))
	}

	bz, err := codec.MarshalJSONIndent(types.ModuleCdc, suppliedCoins)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}

	return bz, nil
}

func queryGetInterestRate(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {
	var params types.QueryInterestRateParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}

	var moneyMarketInterestRates types.MoneyMarketInterestRates
	var moneyMarkets types.MoneyMarkets
	if len(params.Denom) > 0 {
		moneyMarket, found := k.GetMoneyMarket(ctx, params.Denom)
		if !found {
			return nil, types.ErrMoneyMarketNotFound
		}
		moneyMarkets = append(moneyMarkets, moneyMarket)
	} else {
		moneyMarkets = k.GetAllMoneyMarkets(ctx)
	}

	// Calculate the borrow and supply APY interest rates for each money market
	for _, moneyMarket := range moneyMarkets {
		denom := moneyMarket.Denom
		cash := k.supplyKeeper.GetModuleAccount(ctx, types.ModuleName).GetCoins().AmountOf(denom)

		borrowed := sdk.NewCoin(denom, sdk.ZeroInt())
		borrowedCoins, foundBorrowedCoins := k.GetBorrowedCoins(ctx)
		if foundBorrowedCoins {
			borrowed = sdk.NewCoin(denom, borrowedCoins.AmountOf(denom))
		}

		reserves, foundReserves := k.GetTotalReserves(ctx)
		if !foundReserves {
			reserves = sdk.NewCoins()
		}

		// CalculateBorrowRate calculates the current interest rate based on utilization (the fraction of supply that has been borrowed)
		borrowAPY, err := CalculateBorrowRate(moneyMarket.InterestRateModel, sdk.NewDecFromInt(cash), sdk.NewDecFromInt(borrowed.Amount), sdk.NewDecFromInt(reserves.AmountOf(denom)))
		if err != nil {
			return nil, err
		}

		utilRatio := CalculateUtilizationRatio(sdk.NewDecFromInt(cash), sdk.NewDecFromInt(borrowed.Amount), sdk.NewDecFromInt(reserves.AmountOf(denom)))
		fullSupplyAPY := borrowAPY.Mul(utilRatio)
		realSupplyAPY := fullSupplyAPY.Mul(sdk.OneDec().Sub(moneyMarket.ReserveFactor))

		moneyMarketInterestRate := types.MoneyMarketInterestRate{
			Denom:              denom,
			SupplyInterestRate: realSupplyAPY,
			BorrowInterestRate: borrowAPY,
		}

		moneyMarketInterestRates = append(moneyMarketInterestRates, moneyMarketInterestRate)
	}

	bz, err := codec.MarshalJSONIndent(types.ModuleCdc, moneyMarketInterestRates)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}

	return bz, nil
}

func queryGetReserves(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {
	var params types.QueryReservesParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}

	reserveCoins, found := k.GetTotalReserves(ctx)
	if !found {
		reserveCoins = sdk.Coins{}
	}

	// If user specified a denom only return coins of that denom type
	if len(params.Denom) > 0 {
		reserveCoins = sdk.NewCoins(sdk.NewCoin(params.Denom, reserveCoins.AmountOf(params.Denom)))
	}

	bz, err := codec.MarshalJSONIndent(types.ModuleCdc, reserveCoins)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}

	return bz, nil
}

func queryGetInterestFactors(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {
	var params types.QueryInterestFactorsParams
	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
	}

	var interestFactors types.InterestFactors
	if len(params.Denom) > 0 {
		// Fetch supply/borrow interest factors for a single denom
		interestFactor := types.InterestFactor{}
		interestFactor.Denom = params.Denom
		supplyInterestFactor, found := k.GetSupplyInterestFactor(ctx, params.Denom)
		if found {
			interestFactor.SupplyInterestFactor = supplyInterestFactor
		}
		borrowInterestFactor, found := k.GetBorrowInterestFactor(ctx, params.Denom)
		if found {
			interestFactor.BorrowInterestFactor = borrowInterestFactor
		}
		interestFactors = append(interestFactors, interestFactor)
	} else {
		interestFactorMap := make(map[string]types.InterestFactor)
		// Populate mapping with supply interest factors
		k.IterateSupplyInterestFactors(ctx, func(denom string, factor sdk.Dec) (stop bool) {
			interestFactor := types.InterestFactor{Denom: denom, SupplyInterestFactor: factor}
			interestFactorMap[denom] = interestFactor
			return false
		})
		// Populate mapping with borrow interest factors
		k.IterateBorrowInterestFactors(ctx, func(denom string, factor sdk.Dec) (stop bool) {
			interestFactor, ok := interestFactorMap[denom]
			if !ok {
				newInterestFactor := types.InterestFactor{Denom: denom, BorrowInterestFactor: factor}
				interestFactorMap[denom] = newInterestFactor
			} else {
				interestFactor.BorrowInterestFactor = factor
				interestFactorMap[denom] = interestFactor
			}
			return false
		})
		// Translate mapping to slice
		for _, val := range interestFactorMap {
			interestFactors = append(interestFactors, val)
		}
	}

	bz, err := codec.MarshalJSONIndent(types.ModuleCdc, interestFactors)
	if err != nil {
		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
	}

	return bz, nil
}