// Copyright 2021 Evmos Foundation
// This file is part of Evmos' Ethermint library.
//
// The Ethermint library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The Ethermint library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the Ethermint library. If not, see https://github.com/evmos/ethermint/blob/main/LICENSE
package main

import (
	"encoding/json"
	"errors"
	"fmt"

	"github.com/ethereum/go-ethereum/common"
	"github.com/spf13/cobra"

	"github.com/cosmos/cosmos-sdk/client"
	"github.com/cosmos/cosmos-sdk/client/flags"
	"github.com/cosmos/cosmos-sdk/server"
	sdk "github.com/cosmos/cosmos-sdk/types"
	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
	authvesting "github.com/cosmos/cosmos-sdk/x/auth/vesting/types"
	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
	"github.com/cosmos/cosmos-sdk/x/genutil"
	genutiltypes "github.com/cosmos/cosmos-sdk/x/genutil/types"

	"github.com/evmos/ethermint/crypto/hd"
	ethermint "github.com/evmos/ethermint/types"
	evmtypes "github.com/evmos/ethermint/x/evm/types"
)

const (
	flagVestingStart = "vesting-start-time"
	flagVestingEnd   = "vesting-end-time"
	flagVestingAmt   = "vesting-amount"
)

// AddGenesisAccountCmd returns add-genesis-account cobra Command.
func AddGenesisAccountCmd(defaultNodeHome string) *cobra.Command {
	cmd := &cobra.Command{
		Use:   "add-genesis-account ADDRESS_OR_KEY_NAME COIN...",
		Short: "Add a genesis account to genesis.json",
		Long: `Add a genesis account to genesis.json. The provided account must specify
the account address or key name and a list of initial coins. If a key name is given,
the address will be looked up in the local Keybase. The list of initial tokens must
contain valid denominations. Accounts may optionally be supplied with vesting parameters.
`,
		Args: cobra.ExactArgs(2),
		RunE: func(cmd *cobra.Command, args []string) error {
			clientCtx := client.GetClientContextFromCmd(cmd).WithKeyringOptions(hd.EthSecp256k1Option())
			clientCtx, err := client.ReadPersistentCommandFlags(clientCtx, cmd.Flags())
			if err != nil {
				return err
			}

			serverCtx := server.GetServerContextFromCmd(cmd)
			config := serverCtx.Config

			config.SetRoot(clientCtx.HomeDir)

			kr := clientCtx.Keyring
			addr, err := sdk.AccAddressFromBech32(args[0])
			if err != nil {
				info, err := kr.Key(args[0])
				if err != nil {
					return fmt.Errorf("failed to get address from Keyring: %w", err)
				}

				addr, err = info.GetAddress()
				if err != nil {
					return err
				}
			}

			coins, err := sdk.ParseCoinsNormalized(args[1])
			if err != nil {
				return fmt.Errorf("failed to parse coins: %w", err)
			}

			vestingStart, err := cmd.Flags().GetInt64(flagVestingStart)
			if err != nil {
				return err
			}
			vestingEnd, err := cmd.Flags().GetInt64(flagVestingEnd)
			if err != nil {
				return err
			}
			vestingAmtStr, err := cmd.Flags().GetString(flagVestingAmt)
			if err != nil {
				return err
			}

			vestingAmt, err := sdk.ParseCoinsNormalized(vestingAmtStr)
			if err != nil {
				return fmt.Errorf("failed to parse vesting amount: %w", err)
			}

			// create concrete account type based on input parameters
			var genAccount authtypes.GenesisAccount

			balances := banktypes.Balance{Address: addr.String(), Coins: coins.Sort()}
			baseAccount := authtypes.NewBaseAccount(addr, nil, 0, 0)

			if !vestingAmt.IsZero() {
				baseVestingAccount := authvesting.NewBaseVestingAccount(baseAccount, vestingAmt.Sort(), vestingEnd)

				if (balances.Coins.IsZero() && !baseVestingAccount.OriginalVesting.IsZero()) ||
					baseVestingAccount.OriginalVesting.IsAnyGT(balances.Coins) {
					return errors.New("vesting amount cannot be greater than total amount")
				}

				switch {
				case vestingStart != 0 && vestingEnd != 0:
					genAccount = authvesting.NewContinuousVestingAccountRaw(baseVestingAccount, vestingStart)

				case vestingEnd != 0:
					genAccount = authvesting.NewDelayedVestingAccountRaw(baseVestingAccount)

				default:
					return errors.New("invalid vesting parameters; must supply start and end time or end time")
				}
			} else {
				genAccount = &ethermint.EthAccount{
					BaseAccount: baseAccount,
					CodeHash:    common.BytesToHash(evmtypes.EmptyCodeHash).Hex(),
				}
			}

			if err := genAccount.Validate(); err != nil {
				return fmt.Errorf("failed to validate new genesis account: %w", err)
			}

			genFile := config.GenesisFile()
			appState, genDoc, err := genutiltypes.GenesisStateFromGenFile(genFile)
			if err != nil {
				return fmt.Errorf("failed to unmarshal genesis state: %w", err)
			}

			authGenState := authtypes.GetGenesisStateFromAppState(clientCtx.Codec, appState)

			accs, err := authtypes.UnpackAccounts(authGenState.Accounts)
			if err != nil {
				return fmt.Errorf("failed to get accounts from any: %w", err)
			}

			if accs.Contains(addr) {
				return fmt.Errorf("cannot add account at existing address %s", addr)
			}

			// Add the new account to the set of genesis accounts and sanitize the
			// accounts afterwards.
			accs = append(accs, genAccount)
			accs = authtypes.SanitizeGenesisAccounts(accs)

			genAccs, err := authtypes.PackAccounts(accs)
			if err != nil {
				return fmt.Errorf("failed to convert accounts into any's: %w", err)
			}
			authGenState.Accounts = genAccs

			authGenStateBz, err := clientCtx.Codec.MarshalJSON(&authGenState)
			if err != nil {
				return fmt.Errorf("failed to marshal auth genesis state: %w", err)
			}

			appState[authtypes.ModuleName] = authGenStateBz

			bankGenState := banktypes.GetGenesisStateFromAppState(clientCtx.Codec, appState)
			bankGenState.Balances = append(bankGenState.Balances, balances)
			bankGenState.Balances = banktypes.SanitizeGenesisBalances(bankGenState.Balances)
			bankGenState.Supply = bankGenState.Supply.Add(balances.Coins...)

			bankGenStateBz, err := clientCtx.Codec.MarshalJSON(bankGenState)
			if err != nil {
				return fmt.Errorf("failed to marshal bank genesis state: %w", err)
			}

			appState[banktypes.ModuleName] = bankGenStateBz

			appStateJSON, err := json.Marshal(appState)
			if err != nil {
				return fmt.Errorf("failed to marshal application genesis state: %w", err)
			}

			genDoc.AppState = appStateJSON
			return genutil.ExportGenesisFile(genDoc, genFile)
		},
	}

	cmd.Flags().String(flags.FlagHome, defaultNodeHome, "The application home directory")
	cmd.Flags().String(flags.FlagKeyringBackend, flags.DefaultKeyringBackend, "Select keyring's backend (os|file|kwallet|pass|test)")
	cmd.Flags().String(flagVestingAmt, "", "amount of coins for vesting accounts")
	cmd.Flags().Int64(flagVestingStart, 0, "schedule start time (unix epoch) for vesting accounts")
	cmd.Flags().Int64(flagVestingEnd, 0, "schedule end time (unix epoch) for vesting accounts")
	flags.AddQueryFlagsToCmd(cmd)

	return cmd
}