package cli

import (
	"bufio"
	"encoding/hex"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"os"
	"strings"

	"github.com/filecoin-project/go-address"
	types "github.com/filecoin-project/lotus/chain/types"
	"github.com/filecoin-project/lotus/chain/wallet"
	"github.com/filecoin-project/specs-actors/actors/crypto"
	"golang.org/x/xerrors"

	"gopkg.in/urfave/cli.v2"
)

var walletCmd = &cli.Command{
	Name:  "wallet",
	Usage: "Manage wallet",
	Subcommands: []*cli.Command{
		walletNew,
		walletList,
		walletBalance,
		walletExport,
		walletImport,
		walletGetDefault,
		walletSetDefault,
		walletSign,
		walletVerify,
		walletDelete,
	},
}

var walletNew = &cli.Command{
	Name:      "new",
	Usage:     "Generate a new key of the given type",
	ArgsUsage: "[bls|secp256k1 (default secp256k1)]",
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		t := cctx.Args().First()
		if t == "" {
			t = "secp256k1"
		}

		nk, err := api.WalletNew(ctx, wallet.ActSigType(t))
		if err != nil {
			return err
		}

		fmt.Println(nk.String())

		return nil
	},
}

var walletList = &cli.Command{
	Name:  "list",
	Usage: "List wallet address",
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		addrs, err := api.WalletList(ctx)
		if err != nil {
			return err
		}

		for _, addr := range addrs {
			fmt.Println(addr.String())
		}
		return nil
	},
}

var walletBalance = &cli.Command{
	Name:      "balance",
	Usage:     "Get account balance",
	ArgsUsage: "[address]",
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		var addr address.Address
		if cctx.Args().First() != "" {
			addr, err = address.NewFromString(cctx.Args().First())
		} else {
			addr, err = api.WalletDefaultAddress(ctx)
		}
		if err != nil {
			return err
		}

		balance, err := api.WalletBalance(ctx, addr)
		if err != nil {
			return err
		}

		if balance.Equals(types.NewInt(0)) {
			fmt.Printf("%s (warning: may display 0 if chain sync in progress)\n", types.FIL(balance))
		} else {
			fmt.Printf("%s\n", types.FIL(balance))
		}

		return nil
	},
}

var walletGetDefault = &cli.Command{
	Name:  "default",
	Usage: "Get default wallet address",
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		addr, err := api.WalletDefaultAddress(ctx)
		if err != nil {
			return err
		}

		fmt.Printf("%s\n", addr.String())
		return nil
	},
}

var walletSetDefault = &cli.Command{
	Name:      "set-default",
	Usage:     "Set default wallet address",
	ArgsUsage: "[address]",
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		if !cctx.Args().Present() {
			return fmt.Errorf("must pass address to set as default")
		}

		addr, err := address.NewFromString(cctx.Args().First())
		if err != nil {
			return err
		}

		return api.WalletSetDefault(ctx, addr)
	},
}

var walletExport = &cli.Command{
	Name:      "export",
	Usage:     "export keys",
	ArgsUsage: "[address]",
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		if !cctx.Args().Present() {
			return fmt.Errorf("must specify key to export")
		}

		addr, err := address.NewFromString(cctx.Args().First())
		if err != nil {
			return err
		}

		ki, err := api.WalletExport(ctx, addr)
		if err != nil {
			return err
		}

		b, err := json.Marshal(ki)
		if err != nil {
			return err
		}

		fmt.Println(hex.EncodeToString(b))
		return nil
	},
}

var walletImport = &cli.Command{
	Name:      "import",
	Usage:     "import keys",
	ArgsUsage: "[<path> (optional, will read from stdin if omitted)]",
	Flags: []cli.Flag{
		&cli.StringFlag{
			Name:  "format",
			Usage: "specify input format for key",
			Value: "hex-lotus",
		},
	},
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		var inpdata []byte
		if !cctx.Args().Present() || cctx.Args().First() == "-" {
			reader := bufio.NewReader(os.Stdin)
			fmt.Print("Enter private key: ")
			indata, err := reader.ReadBytes('\n')
			if err != nil {
				return err
			}
			inpdata = indata

		} else {
			fdata, err := ioutil.ReadFile(cctx.Args().First())
			if err != nil {
				return err
			}
			inpdata = fdata
		}

		var ki types.KeyInfo
		switch cctx.String("format") {
		case "hex-lotus":
			data, err := hex.DecodeString(strings.TrimSpace(string(inpdata)))
			if err != nil {
				return err
			}

			if err := json.Unmarshal(data, &ki); err != nil {
				return err
			}
		case "json-lotus":
			if err := json.Unmarshal(inpdata, &ki); err != nil {
				return err
			}
		case "gfc-json":
			var f struct {
				KeyInfo []struct {
					PrivateKey []byte
					SigType    int
				}
			}
			if err := json.Unmarshal(inpdata, &f); err != nil {
				return xerrors.Errorf("failed to parse go-filecoin key: %s", err)
			}

			gk := f.KeyInfo[0]
			ki.PrivateKey = gk.PrivateKey
			switch gk.SigType {
			case 1:
				ki.Type = wallet.KTSecp256k1
			case 2:
				ki.Type = wallet.KTBLS
			default:
				return fmt.Errorf("unrecognized key type: %d", gk.SigType)
			}
		default:
			return fmt.Errorf("unrecognized format: %s", cctx.String("format"))
		}

		addr, err := api.WalletImport(ctx, &ki)
		if err != nil {
			return err
		}

		fmt.Printf("imported key %s successfully!\n", addr)
		return nil
	},
}

var walletSign = &cli.Command{
	Name:      "sign",
	Usage:     "sign a message",
	ArgsUsage: "<signing address> <hexMessage>",
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		if !cctx.Args().Present() || cctx.NArg() != 2 {
			return fmt.Errorf("must specify signing address and message to sign")
		}

		addr, err := address.NewFromString(cctx.Args().First())

		if err != nil {
			return err
		}

		msg, err := hex.DecodeString(cctx.Args().Get(1))

		if err != nil {
			return err
		}

		sig, err := api.WalletSign(ctx, addr, msg)

		if err != nil {
			return err
		}

		sigBytes := append([]byte{byte(sig.Type)}, sig.Data...)

		fmt.Println(hex.EncodeToString(sigBytes))
		return nil
	},
}

var walletVerify = &cli.Command{
	Name:      "verify",
	Usage:     "verify the signature of a message",
	ArgsUsage: "<signing address> <hexMessage> <signature>",
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		if !cctx.Args().Present() || cctx.NArg() != 3 {
			return fmt.Errorf("must specify signing address, message, and signature to verify")
		}

		addr, err := address.NewFromString(cctx.Args().First())

		if err != nil {
			return err
		}

		msg, err := hex.DecodeString(cctx.Args().Get(1))

		if err != nil {
			return err
		}

		sigBytes, err := hex.DecodeString(cctx.Args().Get(2))

		if err != nil {
			return err
		}

		var sig crypto.Signature
		if err := sig.UnmarshalBinary(sigBytes); err != nil {
			return err
		}

		if api.WalletVerify(ctx, addr, msg, &sig) {
			fmt.Println("valid")
			return nil
		} else {
			fmt.Println("invalid")
			return NewCliError("CLI Verify called with invalid signature")
		}
	},
}

var walletDelete = &cli.Command{
	Name:      "delete",
	Usage:     "Delete an account from the wallet",
	ArgsUsage: "<address> ",
	Action: func(cctx *cli.Context) error {
		api, closer, err := GetFullNodeAPI(cctx)
		if err != nil {
			return err
		}
		defer closer()
		ctx := ReqContext(cctx)

		if !cctx.Args().Present() || cctx.NArg() != 1 {
			return fmt.Errorf("must specify address to delete")
		}

		addr, err := address.NewFromString(cctx.Args().First())
		if err != nil {
			return err
		}

		return api.WalletDelete(ctx, addr)
	},
}