package keeper

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"math/big"
	"strconv"

	"colinear/x/colinearcore/memdb"
	"colinear/x/colinearcore/types"

	sdk "github.com/cosmos/cosmos-sdk/types"
)

func (k msgServer) NewAuction(goCtx context.Context, msg *types.MsgNewAuction) (*types.MsgNewAuctionResponse, error) {
	ctx := sdk.UnwrapSDKContext(goCtx)

	next, found := k.Keeper.GetNextAuction(ctx)
	if !found {
		return nil, errors.New("unable to get next auction index")
	}
	index := strconv.FormatUint(next.AuctionId, 10)

	auctionLen := msg.LeaseEnd - uint64(ctx.BlockTime().Unix())

	// check that submitted denom is allowed
	for _, denom := range k.GetParams(ctx).AllowedAuctionDenoms {
		if msg.Denom == denom {
			goto found
		}
	}
	return nil, fmt.Errorf("denom %s is not allowed; must be in %v", msg.Denom, k.GetParams(ctx).AllowedAuctionDenoms)
found:

	if uint32(auctionLen) < k.GetParams(ctx).MinLeasePeriod {
		return nil, fmt.Errorf(
			"Auction length %d is below min lease period of %d",
			auctionLen,
			k.GetParams(ctx).MinLeasePeriod,
		)
	}

	if uint32(auctionLen) > k.GetParams(ctx).MaxLeasePeriod {
		return nil, fmt.Errorf(
			"Auction length %d is above max lease period of %d",
			auctionLen,
			k.GetParams(ctx).MaxLeasePeriod,
		)
	}

	senderAddr, err := sdk.AccAddressFromBech32(msg.Creator)
	if err != nil {
		return nil, fmt.Errorf("sender address `%s` format invalid (bech32 required)", msg.Creator)
	}

	if uint32(len(msg.VerifiedProviders)) > k.GetParams(ctx).MaxVerifiedProviders {
		return nil, fmt.Errorf("must submit no more than %d verified providers (got %d)", k.GetParams(ctx).MaxVerifiedProviders, len(msg.VerifiedProviders))
	}

	bech32Len := len("colinear") + 39
	for i, provider := range msg.VerifiedProviders {
		if len(provider) > bech32Len {
			return nil, fmt.Errorf("verified provider address %s (#%d) must be no longer than a colinear bech32 address (%d)", provider, i, bech32Len)
		}
	}

	if msg.VerifiedProviders != nil {
		memdb.AuctionDB.SetVerifiedProviders(index, msg.VerifiedProviders)
	} else {
		memdb.AuctionDB.SetVerifiedProviders(index, []string{})
	}

	auction := types.Auction{
		Index:       index,
		Name:        msg.Name,
		Description: msg.Description,
		// best bid -> null
		// Best:        new(types.Bid),
		Deadline: uint64(ctx.BlockHeight()) + uint64(k.GetParams(ctx).AuctionTime),
		Denom:    msg.Denom,
		Owner:    msg.Creator,
		Ceiling:  msg.Ceiling,
		// lease start -> null
		// instead, initialize when auction is finalized
		// LeaseStart: uint64(ctx.BlockTime().Unix()),
		LeaseEnd: msg.LeaseEnd,
		// remaining payout -> null
		// Remaining:  "0",
		Gpus:      msg.Gpus,
		CpuArch:   msg.CpuArch,
		CpuCores:  msg.CpuCores,
		MemMb:     msg.MemMb,
		StorageGb: msg.StorageGb,
	}

	// validate hardware
	if err := k.ValidateAuctionHardware(ctx, auction); err != nil {
		return nil, err
	}

	spendable := k.bank.SpendableCoins(ctx, senderAddr)
	// if balance does not exceed or equal proposed auction ceiling...
	ceiling := new(big.Int)
	ceiling.SetString(auction.Ceiling, 10)
	if spendable.AmountOf(auction.Denom).BigInt().Cmp(ceiling) == -1 {
		return nil, fmt.Errorf("not enough balance to set ceiling %s%s", msg.Ceiling, auction.Denom)
	}

	coins := sdk.NewCoins(sdk.Coin{
		Amount: sdk.NewIntFromBigInt(ceiling),
		Denom:  auction.Denom,
	})

	if err := k.Keeper.bank.SendCoinsFromAccountToModule(ctx, senderAddr, types.ModuleName, coins); err != nil {
		return nil, fmt.Errorf("failed to transfer %s%s", auction.Ceiling, auction.Denom)
	}

	k.Keeper.SetAuction(ctx, auction)
	next.AuctionId++

	k.Keeper.SetNextAuction(ctx, types.NextAuction{AuctionId: next.AuctionId})

	gpuList, err := json.Marshal(msg.Gpus)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal gpu list %v", msg.Gpus)
	}

	ctx.EventManager().EmitEvent(
		sdk.NewEvent(
			types.AuctionCreatedEventType,
			sdk.NewAttribute(types.AuctionCreatedIndex, auction.Index),
			sdk.NewAttribute(types.AuctionCreatedEventCreator, msg.Creator),
			sdk.NewAttribute(types.AuctionCreatedCeiling, msg.Ceiling),
			sdk.NewAttribute(types.AuctionCreatedCpuCores, msg.CpuArch.String()),
			sdk.NewAttribute(types.AuctionCreatedCpuArch, msg.CpuArch.String()),
			sdk.NewAttribute(types.AuctionCreatedGpus, string(gpuList)),
			sdk.NewAttribute(types.AuctionCreatedMemMb, fmt.Sprint(msg.MemMb)),
			sdk.NewAttribute(types.AuctionCreatedStorage, fmt.Sprint(msg.StorageGb)),
		),
	)

	return &types.MsgNewAuctionResponse{
		AuctionId: strconv.FormatUint(next.AuctionId, 10),
	}, nil
}

func (k *Keeper) ValidateAuctionHardware(ctx sdk.Context, a types.Auction) error {

	if a.Gpus == nil {
		return errors.New("GPU list not found")
	}

	// move these to module params later
	if len(a.Gpus) == 0 || len(a.Gpus) > 20 {
		return fmt.Errorf("must order between 1 and 20 GPUs (got %d)", len(a.Gpus))
	}

	for _, gpu := range a.Gpus {
		if _, ok := k.GetParams(ctx).GpuModels[gpu]; !ok {
			return fmt.Errorf("GPU model %s invalid", gpu)
		}
	}

	// move these to module params later
	if a.CpuCores < 1 || a.CpuCores > 12 {
		return fmt.Errorf("CPU Cores must be between 1 and 12 (got %d)", a.CpuCores)
	}

	// move these to module params later
	if a.StorageGb < 25 || a.StorageGb > 2000 {
		return fmt.Errorf("storage must be between 25GB and 2TB (got %dGB)", a.StorageGb)
	}

	return nil
}