package distribution

import (
	"fmt"

	sdk "github.com/cosmos/cosmos-sdk/types"
	"github.com/cosmos/cosmos-sdk/x/distribution/keeper"
	"github.com/cosmos/cosmos-sdk/x/distribution/tags"
	"github.com/cosmos/cosmos-sdk/x/distribution/types"
)

func NewHandler(k keeper.Keeper) sdk.Handler {
	return func(ctx sdk.Context, msg sdk.Msg) sdk.Result {
		// NOTE msg already has validate basic run
		switch msg := msg.(type) {
		case types.MsgSetWithdrawAddress:
			return handleMsgModifyWithdrawAddress(ctx, msg, k)

		case types.MsgWithdrawDelegatorReward:
			return handleMsgWithdrawDelegatorReward(ctx, msg, k)

		case types.MsgWithdrawValidatorCommission:
			return handleMsgWithdrawValidatorCommission(ctx, msg, k)

		default:
			errMsg := fmt.Sprintf("unrecognized distribution message type: %T", msg)
			return sdk.ErrUnknownRequest(errMsg).Result()
		}
	}
}

// These functions assume everything has been authenticated (ValidateBasic passed, and signatures checked)

func handleMsgModifyWithdrawAddress(ctx sdk.Context, msg types.MsgSetWithdrawAddress, k keeper.Keeper) sdk.Result {

	err := k.SetWithdrawAddr(ctx, msg.DelegatorAddress, msg.WithdrawAddress)
	if err != nil {
		return err.Result()
	}

	resTags := sdk.NewTags(
		tags.Category, tags.TxCategory,
		tags.Sender, msg.DelegatorAddress.String(),
	)
	return sdk.Result{
		Tags: resTags,
	}
}

func handleMsgWithdrawDelegatorReward(ctx sdk.Context, msg types.MsgWithdrawDelegatorReward, k keeper.Keeper) sdk.Result {
	rewards, err := k.WithdrawDelegationRewards(ctx, msg.DelegatorAddress, msg.ValidatorAddress)
	if err != nil {
		return err.Result()
	}

	return sdk.Result{
		Tags: sdk.NewTags(
			tags.Rewards, rewards.String(),
			tags.Category, tags.TxCategory,
			tags.Sender, msg.DelegatorAddress.String(),
			tags.Validator, msg.ValidatorAddress.String(),
		),
	}
}

func handleMsgWithdrawValidatorCommission(ctx sdk.Context, msg types.MsgWithdrawValidatorCommission, k keeper.Keeper) sdk.Result {
	commission, err := k.WithdrawValidatorCommission(ctx, msg.ValidatorAddress)
	if err != nil {
		return err.Result()
	}

	return sdk.Result{
		Tags: sdk.NewTags(
			tags.Commission, commission.String(),
			tags.Category, tags.TxCategory,
			tags.Sender, msg.ValidatorAddress.String(),
		),
	}
}