package ibctesting

import (
	"fmt"

	ibctesting "github.com/cosmos/ibc-go/v3/testing"

	//	sdk "github.com/cosmos/cosmos-sdk/types"
	"github.com/stretchr/testify/require"

	clienttypes "github.com/cosmos/ibc-go/v3/modules/core/02-client/types"
	connectiontypes "github.com/cosmos/ibc-go/v3/modules/core/03-connection/types"
	channeltypes "github.com/cosmos/ibc-go/v3/modules/core/04-channel/types"
	commitmenttypes "github.com/cosmos/ibc-go/v3/modules/core/23-commitment/types"
	host "github.com/cosmos/ibc-go/v3/modules/core/24-host"
	"github.com/cosmos/ibc-go/v3/modules/core/exported"
	ibctmtypes "github.com/cosmos/ibc-go/v3/modules/light-clients/07-tendermint/types"
)

// Endpoint is a which represents a channel endpoint and its associated
// client and connections. It contains client, connection, and channel
// configuration parameters. Endpoint functions will utilize the parameters
// set in the configuration structs when executing IBC messages.
type Endpoint struct {
	Chain        *TestChain
	Counterparty *Endpoint
	ClientID     string
	ConnectionID string
	ChannelID    string

	ClientConfig     ibctesting.ClientConfig
	ConnectionConfig *ibctesting.ConnectionConfig
	ChannelConfig    *ibctesting.ChannelConfig
}

// NewEndpoint constructs a new endpoint without the counterparty.
// CONTRACT: the counterparty endpoint must be set by the caller.
func NewEndpoint(
	chain *TestChain, clientConfig ibctesting.ClientConfig,
	connectionConfig *ibctesting.ConnectionConfig, channelConfig *ibctesting.ChannelConfig,
) *Endpoint {
	return &Endpoint{
		Chain:            chain,
		ClientConfig:     clientConfig,
		ConnectionConfig: connectionConfig,
		ChannelConfig:    channelConfig,
	}
}

// NewDefaultEndpoint constructs a new endpoint using default values.
// CONTRACT: the counterparty endpoitn must be set by the caller.
func NewDefaultEndpoint(chain *TestChain) *Endpoint {
	return &Endpoint{
		Chain:            chain,
		ClientConfig:     ibctesting.NewTendermintConfig(),
		ConnectionConfig: ibctesting.NewConnectionConfig(),
		ChannelConfig:    ibctesting.NewChannelConfig(),
	}
}

// QueryProof queries proof associated with this endpoint using the lastest client state
// height on the counterparty chain.
func (endpoint *Endpoint) QueryProof(key []byte) ([]byte, clienttypes.Height) {
	// obtain the counterparty client representing the chain associated with the endpoint
	clientState := endpoint.Counterparty.Chain.GetClientState(endpoint.Counterparty.ClientID)

	// query proof on the counterparty using the latest height of the IBC client
	return endpoint.QueryProofAtHeight(key, clientState.GetLatestHeight().GetRevisionHeight())
}

// QueryProofAtHeight queries proof associated with this endpoint using the proof height
// providied
func (endpoint *Endpoint) QueryProofAtHeight(key []byte, height uint64) ([]byte, clienttypes.Height) {
	// query proof on the counterparty using the latest height of the IBC client
	return endpoint.Chain.QueryProofAtHeight(key, int64(height))
}

// CreateClient creates an IBC client on the endpoint. It will update the
// clientID for the endpoint if the message is successfully executed.
// NOTE: a solo machine client will be created with an empty diversifier.
func (endpoint *Endpoint) CreateClient() (err error) {
	// ensure counterparty has committed state
	endpoint.Chain.Coordinator.CommitBlock(endpoint.Counterparty.Chain)

	var (
		clientState    exported.ClientState
		consensusState exported.ConsensusState
	)

	switch endpoint.ClientConfig.GetClientType() {
	case exported.Tendermint:
		tmConfig, ok := endpoint.ClientConfig.(*ibctesting.TendermintConfig)
		require.True(endpoint.Chain.t, ok)

		height := endpoint.Counterparty.Chain.LastHeader.GetHeight().(clienttypes.Height)
		clientState = ibctmtypes.NewClientState(
			endpoint.Counterparty.Chain.ChainID, tmConfig.TrustLevel, tmConfig.TrustingPeriod, tmConfig.UnbondingPeriod, tmConfig.MaxClockDrift,
			height, commitmenttypes.GetSDKSpecs(), ibctesting.UpgradePath, tmConfig.AllowUpdateAfterExpiry, tmConfig.AllowUpdateAfterMisbehaviour,
		)
		consensusState = endpoint.Counterparty.Chain.LastHeader.ConsensusState()
	case exported.Solomachine:
		// TODO
		//		solo := NewSolomachine(chain.t, endpoint.Chain.Codec, clientID, "", 1)
		//		clientState = solo.ClientState()
		//		consensusState = solo.ConsensusState()

	default:
		err = fmt.Errorf("client type %s is not supported", endpoint.ClientConfig.GetClientType())
	}

	if err != nil {
		return err
	}

	msg, err := clienttypes.NewMsgCreateClient(
		clientState, consensusState, endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	require.NoError(endpoint.Chain.t, err)

	res, err := endpoint.Chain.SendMsgs(msg)
	if err != nil {
		return err
	}

	endpoint.ClientID, err = ibctesting.ParseClientIDFromEvents(res.GetEvents())
	require.NoError(endpoint.Chain.t, err)

	return nil
}

// UpdateClient updates the IBC client associated with the endpoint.
func (endpoint *Endpoint) UpdateClient() (err error) {
	// ensure counterparty has committed state
	endpoint.Chain.Coordinator.CommitBlock(endpoint.Counterparty.Chain)

	var header exported.Header

	switch endpoint.ClientConfig.GetClientType() {
	case exported.Tendermint:
		header, err = endpoint.Chain.ConstructUpdateTMClientHeader(endpoint.Counterparty.Chain, endpoint.ClientID)

	default:
		err = fmt.Errorf("client type %s is not supported", endpoint.ClientConfig.GetClientType())
	}

	if err != nil {
		return err
	}

	msg, err := clienttypes.NewMsgUpdateClient(
		endpoint.ClientID, header,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	require.NoError(endpoint.Chain.t, err)

	return endpoint.Chain.sendMsgs(msg)
}

// ConnOpenInit will construct and execute a MsgConnectionOpenInit on the associated endpoint.
func (endpoint *Endpoint) ConnOpenInit() error {
	msg := connectiontypes.NewMsgConnectionOpenInit(
		endpoint.ClientID,
		endpoint.Counterparty.ClientID,
		endpoint.Counterparty.Chain.GetPrefix(), ibctesting.DefaultOpenInitVersion, endpoint.ConnectionConfig.DelayPeriod,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	res, err := endpoint.Chain.SendMsgs(msg)
	if err != nil {
		return err
	}

	endpoint.ConnectionID, err = ibctesting.ParseConnectionIDFromEvents(res.GetEvents())
	require.NoError(endpoint.Chain.t, err)

	return nil
}

// ConnOpenTry will construct and execute a MsgConnectionOpenTry on the associated endpoint.
func (endpoint *Endpoint) ConnOpenTry() error {
	if err := endpoint.UpdateClient(); err != nil {
		return err
	}

	counterpartyClient, proofClient, proofConsensus, consensusHeight, proofInit, proofHeight := endpoint.QueryConnectionHandshakeProof()

	msg := connectiontypes.NewMsgConnectionOpenTry(
		"", endpoint.ClientID, // does not support handshake continuation
		endpoint.Counterparty.ConnectionID, endpoint.Counterparty.ClientID,
		counterpartyClient, endpoint.Counterparty.Chain.GetPrefix(), []*connectiontypes.Version{ibctesting.ConnectionVersion}, endpoint.ConnectionConfig.DelayPeriod,
		proofInit, proofClient, proofConsensus,
		proofHeight, consensusHeight,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	res, err := endpoint.Chain.SendMsgs(msg)
	if err != nil {
		return err
	}

	if endpoint.ConnectionID == "" {
		endpoint.ConnectionID, err = ibctesting.ParseConnectionIDFromEvents(res.GetEvents())
		require.NoError(endpoint.Chain.t, err)
	}

	return nil
}

// ConnOpenAck will construct and execute a MsgConnectionOpenAck on the associated endpoint.
func (endpoint *Endpoint) ConnOpenAck() error {
	if err := endpoint.UpdateClient(); err != nil {
		return err
	}

	counterpartyClient, proofClient, proofConsensus, consensusHeight, proofTry, proofHeight := endpoint.QueryConnectionHandshakeProof()

	msg := connectiontypes.NewMsgConnectionOpenAck(
		endpoint.ConnectionID, endpoint.Counterparty.ConnectionID, counterpartyClient, // testing doesn't use flexible selection
		proofTry, proofClient, proofConsensus,
		proofHeight, consensusHeight,
		ibctesting.ConnectionVersion,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	return endpoint.Chain.sendMsgs(msg)
}

// ConnOpenConfirm will construct and execute a MsgConnectionOpenConfirm on the associated endpoint.
func (endpoint *Endpoint) ConnOpenConfirm() error {
	if err := endpoint.UpdateClient(); err != nil {
		return err
	}

	connectionKey := host.ConnectionKey(endpoint.Counterparty.ConnectionID)
	proof, height := endpoint.Counterparty.Chain.QueryProof(connectionKey)

	msg := connectiontypes.NewMsgConnectionOpenConfirm(
		endpoint.ConnectionID,
		proof, height,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	return endpoint.Chain.sendMsgs(msg)
}

// QueryConnectionHandshakeProof returns all the proofs necessary to execute OpenTry or Open Ack of
// the connection handshakes. It returns the counterparty client state, proof of the counterparty
// client state, proof of the counterparty consensus state, the consensus state height, proof of
// the counterparty connection, and the proof height for all the proofs returned.
func (endpoint *Endpoint) QueryConnectionHandshakeProof() (
	clientState exported.ClientState, proofClient,
	proofConsensus []byte, consensusHeight clienttypes.Height,
	proofConnection []byte, proofHeight clienttypes.Height,
) {
	// obtain the client state on the counterparty chain
	clientState = endpoint.Counterparty.Chain.GetClientState(endpoint.Counterparty.ClientID)

	// query proof for the client state on the counterparty
	clientKey := host.FullClientStateKey(endpoint.Counterparty.ClientID)
	proofClient, proofHeight = endpoint.Counterparty.QueryProof(clientKey)

	consensusHeight = clientState.GetLatestHeight().(clienttypes.Height)

	// query proof for the consensus state on the counterparty
	consensusKey := host.FullConsensusStateKey(endpoint.Counterparty.ClientID, consensusHeight)
	proofConsensus, _ = endpoint.Counterparty.QueryProofAtHeight(consensusKey, proofHeight.GetRevisionHeight())

	// query proof for the connection on the counterparty
	connectionKey := host.ConnectionKey(endpoint.Counterparty.ConnectionID)
	proofConnection, _ = endpoint.Counterparty.QueryProofAtHeight(connectionKey, proofHeight.GetRevisionHeight())

	return
}

// ChanOpenInit will construct and execute a MsgChannelOpenInit on the associated endpoint.
func (endpoint *Endpoint) ChanOpenInit() error {
	msg := channeltypes.NewMsgChannelOpenInit(
		endpoint.ChannelConfig.PortID,
		endpoint.ChannelConfig.Version, endpoint.ChannelConfig.Order, []string{endpoint.ConnectionID},
		endpoint.Counterparty.ChannelConfig.PortID,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	res, err := endpoint.Chain.SendMsgs(msg)
	if err != nil {
		return err
	}

	endpoint.ChannelID, err = ibctesting.ParseChannelIDFromEvents(res.GetEvents())
	require.NoError(endpoint.Chain.t, err)

	return nil
}

// ChanOpenTry will construct and execute a MsgChannelOpenTry on the associated endpoint.
func (endpoint *Endpoint) ChanOpenTry() error {
	if err := endpoint.UpdateClient(); err != nil {
		return err
	}

	channelKey := host.ChannelKey(endpoint.Counterparty.ChannelConfig.PortID, endpoint.Counterparty.ChannelID)
	proof, height := endpoint.Counterparty.Chain.QueryProof(channelKey)

	msg := channeltypes.NewMsgChannelOpenTry(
		endpoint.ChannelConfig.PortID, "", // does not support handshake continuation
		endpoint.ChannelConfig.Version, endpoint.ChannelConfig.Order, []string{endpoint.ConnectionID},
		endpoint.Counterparty.ChannelConfig.PortID, endpoint.Counterparty.ChannelID, endpoint.Counterparty.ChannelConfig.Version,
		proof, height,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	res, err := endpoint.Chain.SendMsgs(msg)
	if err != nil {
		return err
	}

	if endpoint.ChannelID == "" {
		endpoint.ChannelID, err = ibctesting.ParseChannelIDFromEvents(res.GetEvents())
		require.NoError(endpoint.Chain.t, err)
	}

	return nil
}

// ChanOpenAck will construct and execute a MsgChannelOpenAck on the associated endpoint.
func (endpoint *Endpoint) ChanOpenAck() error {
	if err := endpoint.UpdateClient(); err != nil {
		return err
	}

	channelKey := host.ChannelKey(endpoint.Counterparty.ChannelConfig.PortID, endpoint.Counterparty.ChannelID)
	proof, height := endpoint.Counterparty.Chain.QueryProof(channelKey)

	msg := channeltypes.NewMsgChannelOpenAck(
		endpoint.ChannelConfig.PortID, endpoint.ChannelID,
		endpoint.Counterparty.ChannelID, endpoint.Counterparty.ChannelConfig.Version, // testing doesn't use flexible selection
		proof, height,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	return endpoint.Chain.sendMsgs(msg)
}

// ChanOpenConfirm will construct and execute a MsgChannelOpenConfirm on the associated endpoint.
func (endpoint *Endpoint) ChanOpenConfirm() error {
	if err := endpoint.UpdateClient(); err != nil {
		return err
	}

	channelKey := host.ChannelKey(endpoint.Counterparty.ChannelConfig.PortID, endpoint.Counterparty.ChannelID)
	proof, height := endpoint.Counterparty.Chain.QueryProof(channelKey)

	msg := channeltypes.NewMsgChannelOpenConfirm(
		endpoint.ChannelConfig.PortID, endpoint.ChannelID,
		proof, height,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	return endpoint.Chain.sendMsgs(msg)
}

// ChanCloseInit will construct and execute a MsgChannelCloseInit on the associated endpoint.
//
// NOTE: does not work with ibc-transfer module
func (endpoint *Endpoint) ChanCloseInit() error {
	msg := channeltypes.NewMsgChannelCloseInit(
		endpoint.ChannelConfig.PortID, endpoint.ChannelID,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	return endpoint.Chain.sendMsgs(msg)
}

// ChanCloseConfirm will construct and execute a NewMsgChannelCloseConfirm on the associated endpoint.
func (endpoint *Endpoint) ChanCloseConfirm() error {
	channelKey := host.ChannelKey(endpoint.Counterparty.ChannelConfig.PortID, endpoint.Counterparty.ChannelID)
	proof, proofHeight := endpoint.Counterparty.QueryProof(channelKey)

	msg := channeltypes.NewMsgChannelCloseConfirm(
		endpoint.ChannelConfig.PortID, endpoint.ChannelID,
		proof, proofHeight,
		endpoint.Chain.SenderAccount.GetAddress().String(),
	)
	return endpoint.Chain.sendMsgs(msg)
}

// SendPacket sends a packet through the channel keeper using the associated endpoint
// The counterparty client is updated so proofs can be sent to the counterparty chain.
func (endpoint *Endpoint) SendPacket(packet exported.PacketI) error {
	channelCap := endpoint.Chain.GetChannelCapability(packet.GetSourcePort(), packet.GetSourceChannel())

	// no need to send message, acting as a module
	err := endpoint.Chain.App.GetIBCKeeper().ChannelKeeper.SendPacket(endpoint.Chain.GetContext(), channelCap, packet)
	if err != nil {
		return err
	}

	// commit changes since no message was sent
	endpoint.Chain.Coordinator.CommitBlock(endpoint.Chain)

	return endpoint.Counterparty.UpdateClient()
}

// RecvPacket receives a packet on the associated endpoint.
// The counterparty client is updated.
func (endpoint *Endpoint) RecvPacket(packet channeltypes.Packet) error {
	// get proof of packet commitment on source
	packetKey := host.PacketCommitmentKey(packet.GetSourcePort(), packet.GetSourceChannel(), packet.GetSequence())
	proof, proofHeight := endpoint.Counterparty.Chain.QueryProof(packetKey)

	recvMsg := channeltypes.NewMsgRecvPacket(packet, proof, proofHeight, endpoint.Chain.SenderAccount.GetAddress().String())

	// receive on counterparty and update source client
	if err := endpoint.Chain.sendMsgs(recvMsg); err != nil {
		return err
	}

	return endpoint.Counterparty.UpdateClient()
}

// WriteAcknowledgement writes an acknowledgement on the channel associated with the endpoint.
// The counterparty client is updated.
func (endpoint *Endpoint) WriteAcknowledgement(ack exported.Acknowledgement, packet exported.PacketI) error {
	channelCap := endpoint.Chain.GetChannelCapability(packet.GetDestPort(), packet.GetDestChannel())

	// no need to send message, acting as a handler
	err := endpoint.Chain.App.GetIBCKeeper().ChannelKeeper.WriteAcknowledgement(endpoint.Chain.GetContext(), channelCap, packet, ack)
	if err != nil {
		return err
	}

	// commit changes since no message was sent
	endpoint.Chain.Coordinator.CommitBlock(endpoint.Chain)

	return endpoint.Counterparty.UpdateClient()
}

// AcknowledgePacket sends a MsgAcknowledgement to the channel associated with the endpoint.
func (endpoint *Endpoint) AcknowledgePacket(packet channeltypes.Packet, ack []byte) error {
	// get proof of acknowledgement on counterparty
	packetKey := host.PacketAcknowledgementKey(packet.GetDestPort(), packet.GetDestChannel(), packet.GetSequence())
	proof, proofHeight := endpoint.Counterparty.QueryProof(packetKey)

	ackMsg := channeltypes.NewMsgAcknowledgement(packet, ack, proof, proofHeight, endpoint.Chain.SenderAccount.GetAddress().String())

	return endpoint.Chain.sendMsgs(ackMsg)
}

// TimeoutPacket sends a MsgTimeout to the channel associated with the endpoint.
func (endpoint *Endpoint) TimeoutPacket(packet channeltypes.Packet) error {
	// get proof for timeout based on channel order
	var packetKey []byte

	switch endpoint.ChannelConfig.Order {
	case channeltypes.ORDERED:
		packetKey = host.NextSequenceRecvKey(packet.GetDestPort(), packet.GetDestChannel())
	case channeltypes.UNORDERED:
		packetKey = host.PacketReceiptKey(packet.GetDestPort(), packet.GetDestChannel(), packet.GetSequence())
	default:
		return fmt.Errorf("unsupported order type %s", endpoint.ChannelConfig.Order)
	}

	proof, proofHeight := endpoint.Counterparty.QueryProof(packetKey)
	nextSeqRecv, found := endpoint.Counterparty.Chain.App.GetIBCKeeper().ChannelKeeper.GetNextSequenceRecv(endpoint.Counterparty.Chain.GetContext(), endpoint.ChannelConfig.PortID, endpoint.ChannelID)
	require.True(endpoint.Chain.t, found)

	timeoutMsg := channeltypes.NewMsgTimeout(
		packet, nextSeqRecv,
		proof, proofHeight, endpoint.Chain.SenderAccount.GetAddress().String(),
	)

	return endpoint.Chain.sendMsgs(timeoutMsg)
}

// SetChannelClosed sets a channel state to CLOSED.
func (endpoint *Endpoint) SetChannelClosed() error {
	channel := endpoint.GetChannel()

	channel.State = channeltypes.CLOSED
	endpoint.Chain.App.GetIBCKeeper().ChannelKeeper.SetChannel(endpoint.Chain.GetContext(), endpoint.ChannelConfig.PortID, endpoint.ChannelID, channel)

	endpoint.Chain.Coordinator.CommitBlock(endpoint.Chain)

	return endpoint.Counterparty.UpdateClient()
}

// GetClientState retrieves the Client State for this endpoint. The
// client state is expected to exist otherwise testing will fail.
func (endpoint *Endpoint) GetClientState() exported.ClientState {
	return endpoint.Chain.GetClientState(endpoint.ClientID)
}

// SetClientState sets the client state for this endpoint.
func (endpoint *Endpoint) SetClientState(clientState exported.ClientState) {
	endpoint.Chain.App.GetIBCKeeper().ClientKeeper.SetClientState(endpoint.Chain.GetContext(), endpoint.ClientID, clientState)
}

// GetConsensusState retrieves the Consensus State for this endpoint at the provided height.
// The consensus state is expected to exist otherwise testing will fail.
func (endpoint *Endpoint) GetConsensusState(height exported.Height) exported.ConsensusState {
	consensusState, found := endpoint.Chain.GetConsensusState(endpoint.ClientID, height)
	require.True(endpoint.Chain.t, found)

	return consensusState
}

// SetConsensusState sets the consensus state for this endpoint.
func (endpoint *Endpoint) SetConsensusState(consensusState exported.ConsensusState, height exported.Height) {
	endpoint.Chain.App.GetIBCKeeper().ClientKeeper.SetClientConsensusState(endpoint.Chain.GetContext(), endpoint.ClientID, height, consensusState)
}

// GetConnection retrieves an IBC Connection for the endpoint. The
// connection is expected to exist otherwise testing will fail.
func (endpoint *Endpoint) GetConnection() connectiontypes.ConnectionEnd {
	connection, found := endpoint.Chain.App.GetIBCKeeper().ConnectionKeeper.GetConnection(endpoint.Chain.GetContext(), endpoint.ConnectionID)
	require.True(endpoint.Chain.t, found)

	return connection
}

// SetConnection sets the connection for this endpoint.
func (endpoint *Endpoint) SetConnection(connection connectiontypes.ConnectionEnd) {
	endpoint.Chain.App.GetIBCKeeper().ConnectionKeeper.SetConnection(endpoint.Chain.GetContext(), endpoint.ConnectionID, connection)
}

// GetChannel retrieves an IBC Channel for the endpoint. The channel
// is expected to exist otherwise testing will fail.
func (endpoint *Endpoint) GetChannel() channeltypes.Channel {
	channel, found := endpoint.Chain.App.GetIBCKeeper().ChannelKeeper.GetChannel(endpoint.Chain.GetContext(), endpoint.ChannelConfig.PortID, endpoint.ChannelID)
	require.True(endpoint.Chain.t, found)

	return channel
}

// SetChannel sets the channel for this endpoint.
func (endpoint *Endpoint) SetChannel(channel channeltypes.Channel) {
	endpoint.Chain.App.GetIBCKeeper().ChannelKeeper.SetChannel(endpoint.Chain.GetContext(), endpoint.ChannelConfig.PortID, endpoint.ChannelID, channel)
}

// QueryClientStateProof performs and abci query for a client stat associated
// with this endpoint and returns the ClientState along with the proof.
func (endpoint *Endpoint) QueryClientStateProof() (exported.ClientState, []byte) {
	// retrieve client state to provide proof for
	clientState := endpoint.GetClientState()

	clientKey := host.FullClientStateKey(endpoint.ClientID)
	proofClient, _ := endpoint.QueryProof(clientKey)

	return clientState, proofClient
}