package main

import (
	"encoding/json"
	"fmt"
	"io/ioutil"

	"github.com/google/uuid"
	"github.com/mitchellh/go-homedir"
	"github.com/urfave/cli/v2"
	"golang.org/x/xerrors"

	"github.com/filecoin-project/go-address"
	"github.com/filecoin-project/specs-actors/actors/abi"
	"github.com/filecoin-project/specs-actors/actors/abi/big"

	"github.com/filecoin-project/lotus/build"
	genesis2 "github.com/filecoin-project/lotus/chain/gen/genesis"
	"github.com/filecoin-project/lotus/genesis"
)

var genesisCmd = &cli.Command{
	Name:        "genesis",
	Description: "manipulate lotus genesis template",
	Subcommands: []*cli.Command{
		genesisNewCmd,
		genesisAddMinerCmd,
		genesisAddMsigsCmd,
	},
}

var genesisNewCmd = &cli.Command{
	Name:        "new",
	Description: "create new genesis template",
	Flags: []cli.Flag{
		&cli.StringFlag{
			Name: "network-name",
		},
	},
	Action: func(cctx *cli.Context) error {
		if !cctx.Args().Present() {
			return xerrors.New("seed genesis new [genesis.json]")
		}

		out := genesis.Template{
			Accounts:    []genesis.Actor{},
			Miners:      []genesis.Miner{},
			NetworkName: cctx.String("network-name"),
		}
		if out.NetworkName == "" {
			out.NetworkName = "localnet-" + uuid.New().String()
		}

		genb, err := json.MarshalIndent(&out, "", "  ")
		if err != nil {
			return err
		}

		genf, err := homedir.Expand(cctx.Args().First())
		if err != nil {
			return err
		}

		if err := ioutil.WriteFile(genf, genb, 0644); err != nil {
			return err
		}

		return nil
	},
}

var genesisAddMinerCmd = &cli.Command{
	Name:        "add-miner",
	Description: "add genesis miner",
	Flags:       []cli.Flag{},
	Action: func(cctx *cli.Context) error {
		if cctx.Args().Len() != 2 {
			return xerrors.New("seed genesis add-miner [genesis.json] [preseal.json]")
		}

		genf, err := homedir.Expand(cctx.Args().First())
		if err != nil {
			return err
		}

		var template genesis.Template
		genb, err := ioutil.ReadFile(genf)
		if err != nil {
			return xerrors.Errorf("read genesis template: %w", err)
		}

		if err := json.Unmarshal(genb, &template); err != nil {
			return xerrors.Errorf("unmarshal genesis template: %w", err)
		}

		minf, err := homedir.Expand(cctx.Args().Get(1))
		if err != nil {
			return xerrors.Errorf("expand preseal file path: %w", err)
		}
		miners := map[string]genesis.Miner{}
		minb, err := ioutil.ReadFile(minf)
		if err != nil {
			return xerrors.Errorf("read preseal file: %w", err)
		}
		if err := json.Unmarshal(minb, &miners); err != nil {
			return xerrors.Errorf("unmarshal miner info: %w", err)
		}

		for mn, miner := range miners {
			log.Infof("Adding miner %s to genesis template", mn)
			{
				id := uint64(genesis2.MinerStart) + uint64(len(template.Miners))
				maddr, err := address.NewFromString(mn)
				if err != nil {
					return xerrors.Errorf("parsing miner address: %w", err)
				}
				mid, err := address.IDFromAddress(maddr)
				if err != nil {
					return xerrors.Errorf("getting miner id from address: %w", err)
				}
				if mid != id {
					return xerrors.Errorf("tried to set miner t0%d as t0%d", mid, id)
				}
			}

			template.Miners = append(template.Miners, miner)
			log.Infof("Giving %s some initial balance", miner.Owner)
			template.Accounts = append(template.Accounts, genesis.Actor{
				Type:    genesis.TAccount,
				Balance: big.Mul(big.NewInt(50_000_000), big.NewInt(int64(build.FilecoinPrecision))),
				Meta:    (&genesis.AccountMeta{Owner: miner.Owner}).ActorMeta(),
			})
		}

		genb, err = json.MarshalIndent(&template, "", "  ")
		if err != nil {
			return err
		}

		if err := ioutil.WriteFile(genf, genb, 0644); err != nil {
			return err
		}

		return nil
	},
}

type GenAccountEntry struct {
	ID          string
	CustodianID int
	M           int
	N           int
	Addresses   []address.Address
	Type        string
	Sig1        string
	Sig2        string
}

var genesisAddMsigsCmd = &cli.Command{
	Name: "add-msigs",
	Action: func(cctx *cli.Context) error {
		if cctx.Args().Len() < 2 {
			return fmt.Errorf("must specify template file and csv file with accounts")
		}

		genf, err := homedir.Expand(cctx.Args().First())
		if err != nil {
			return err
		}

		var template genesis.Template
		b, err := ioutil.ReadFile(genf)
		if err != nil {
			return xerrors.Errorf("read genesis template: %w", err)
		}

		if err := json.Unmarshal(b, &template); err != nil {
			return xerrors.Errorf("unmarshal genesis template: %w", err)
		}

		var entries []GenAccountEntry
		// TODO: parse that csv

		for i, e := range entries {
			if len(e.Addresses) != e.N {
				return fmt.Errorf("entry %d had mismatch between 'N' and number of addresses", i)
			}

			msig := &genesis.MultisigMeta{
				Signers:         e.Addresses,
				Threshold:       e.M,
				VestingDuration: 0, // TODO
				VestingStart:    0, // TODO
			}

			act := genesis.Actor{
				Type:    genesis.TMultisig,
				Balance: abi.NewTokenAmount(0), // TODO
				Meta:    msig.ActorMeta(),
			}

			template.Accounts = append(template.Accounts, act)

		}

		b, err = json.MarshalIndent(&template, "", "  ")
		if err != nil {
			return err
		}

		if err := ioutil.WriteFile(genf, b, 0644); err != nil {
			return err
		}
		return nil
	},
}