package commands

import (
	"encoding/hex"
	"fmt"

	"github.com/spf13/cobra"
	"github.com/spf13/viper"

	"github.com/cosmos/cosmos-sdk/client/context"
	sdk "github.com/cosmos/cosmos-sdk/types"
	"github.com/cosmos/cosmos-sdk/wire"
	authcmd "github.com/cosmos/cosmos-sdk/x/auth/commands"
	"github.com/cosmos/cosmos-sdk/x/bank"
)

const (
	flagTo     = "to"
	flagAmount = "amount"
)

// SendTxCommand will create a send tx and sign it with the given key
func SendTxCmd(cdc *wire.Codec) *cobra.Command {
	cmd := &cobra.Command{
		Use:   "send",
		Short: "Create and sign a send tx",
		RunE: func(cmd *cobra.Command, args []string) error {
			ctx := context.NewCoreContextFromViper().WithDecoder(authcmd.GetAccountDecoder(cdc))

			// get the from/to address
			from, err := ctx.GetFromAddress()
			if err != nil {
				return err
			}

			toStr := viper.GetString(flagTo)
			bz, err := hex.DecodeString(toStr)
			if err != nil {
				return err
			}
			to := sdk.Address(bz)

			// parse coins
			amount := viper.GetString(flagAmount)
			coins, err := sdk.ParseCoins(amount)
			if err != nil {
				return err
			}

			// build and sign the transaction, then broadcast to Tendermint
			msg := BuildMsg(from, to, coins)
			res, err := ctx.EnsureSignBuildBroadcast(ctx.FromAddressName, msg, cdc)
			if err != nil {
				return err
			}
			fmt.Printf("Committed at block %d. Hash: %s\n", res.Height, res.Hash.String())
			return nil
		},
	}

	cmd.Flags().String(flagTo, "", "Address to send coins")
	cmd.Flags().String(flagAmount, "", "Amount of coins to send")
	return cmd
}

// build the sendTx msg
func BuildMsg(from sdk.Address, to sdk.Address, coins sdk.Coins) sdk.Msg {
	input := bank.NewInput(from, coins)
	output := bank.NewOutput(to, coins)
	msg := bank.NewMsgSend([]bank.Input{input}, []bank.Output{output})
	return msg
}