// VulcanizeDB
// Copyright © 2019 Vulcanize

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program 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 Affero General Public License for more details.

// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package fakes

import (
	"context"
	"errors"
	"github.com/ethereum/go-ethereum/statediff"
	"math/big"

	"github.com/ethereum/go-ethereum/core/types"
	"github.com/ethereum/go-ethereum/p2p"
	"github.com/ethereum/go-ethereum/rpc"
	. "github.com/onsi/gomega"

	"github.com/vulcanize/vulcanizedb/pkg/core"
	"github.com/vulcanize/vulcanizedb/pkg/eth/client"
)

type MockRPCClient struct {
	callContextErr      error
	ipcPath             string
	nodeType            core.NodeType
	passedContext       context.Context
	passedMethod        string
	passedResult        interface{}
	passedBatch         []client.BatchElem
	passedNamespace     string
	passedPayloadChan   chan statediff.Payload
	passedSubscribeArgs []interface{}
	lengthOfBatch       int
	returnPOAHeader     core.POAHeader
	returnPOAHeaders    []core.POAHeader
	returnPOWHeaders    []*types.Header
	supportedModules    map[string]string
}

func (client *MockRPCClient) Subscribe(namespace string, payloadChan interface{}, args ...interface{}) (*rpc.ClientSubscription, error) {
	client.passedNamespace = namespace

	passedPayloadChan, ok := payloadChan.(chan statediff.Payload)
	if !ok {
		return nil, errors.New("passed in channel is not of the correct type")
	}
	client.passedPayloadChan = passedPayloadChan

	for _, arg := range args {
		client.passedSubscribeArgs = append(client.passedSubscribeArgs, arg)
	}

	subscription := rpc.ClientSubscription{}
	return &subscription, nil
}

func (client *MockRPCClient) AssertSubscribeCalledWith(namespace string, payloadChan chan statediff.Payload, args []interface{}) {
	Expect(client.passedNamespace).To(Equal(namespace))
	Expect(client.passedPayloadChan).To(Equal(payloadChan))
	Expect(client.passedSubscribeArgs).To(Equal(args))
}

func NewMockRPCClient() *MockRPCClient {
	return &MockRPCClient{}
}

func (client *MockRPCClient) SetIpcPath(ipcPath string) {
	client.ipcPath = ipcPath
}

func (client *MockRPCClient) BatchCall(batch []client.BatchElem) error {
	client.passedBatch = batch
	client.passedMethod = batch[0].Method
	client.lengthOfBatch = len(batch)

	for _, batchElem := range batch {
		client.passedContext = context.Background()
		client.passedResult = &batchElem.Result
		client.passedMethod = batchElem.Method
		if p, ok := batchElem.Result.(*types.Header); ok {
			*p = types.Header{Number: big.NewInt(100)}
		}
		if p, ok := batchElem.Result.(*core.POAHeader); ok {

			*p = client.returnPOAHeader
		}
	}

	return nil
}

func (client *MockRPCClient) CallContext(ctx context.Context, result interface{}, method string, args ...interface{}) error {
	client.passedContext = ctx
	client.passedResult = result
	client.passedMethod = method
	switch method {
	case "admin_nodeInfo":
		if p, ok := result.(*p2p.NodeInfo); ok {
			p.ID = "enode://GethNode@172.17.0.1:30303"
			p.Name = "Geth/v1.7"
		}
	case "eth_getBlockByNumber":
		if p, ok := result.(*types.Header); ok {
			*p = types.Header{Number: big.NewInt(100)}
		}
		if p, ok := result.(*core.POAHeader); ok {

			*p = client.returnPOAHeader
		}
		if client.callContextErr != nil {
			return client.callContextErr
		}
	case "parity_versionInfo":
		if p, ok := result.(*core.ParityNodeInfo); ok {
			*p = core.ParityNodeInfo{
				Track: "",
				ParityVersion: core.ParityVersion{
					Major: 1,
					Minor: 2,
					Patch: 3,
				},
				Hash: "",
			}
		}
	case "parity_enode":
		if p, ok := result.(*string); ok {
			*p = "enode://ParityNode@172.17.0.1:30303"
		}
	case "net_version":
		if p, ok := result.(*string); ok {
			*p = "1234"
		}
	}
	return nil
}

func (client *MockRPCClient) IpcPath() string {
	return client.ipcPath
}

func (client *MockRPCClient) SupportedModules() (map[string]string, error) {
	return client.supportedModules, nil
}

func (client *MockRPCClient) SetSupporedModules(supportedModules map[string]string) {
	client.supportedModules = supportedModules
}

func (client *MockRPCClient) SetCallContextErr(err error) {
	client.callContextErr = err
}

func (client *MockRPCClient) SetReturnPOAHeader(header core.POAHeader) {
	client.returnPOAHeader = header
}

func (client *MockRPCClient) SetReturnPOWHeaders(headers []*types.Header) {
	client.returnPOWHeaders = headers
}

func (client *MockRPCClient) SetReturnPOAHeaders(headers []core.POAHeader) {
	client.returnPOAHeaders = headers
}

func (client *MockRPCClient) AssertCallContextCalledWith(ctx context.Context, result interface{}, method string) {
	Expect(client.passedContext).To(Equal(ctx))
	Expect(client.passedResult).To(BeAssignableToTypeOf(result))
	Expect(client.passedMethod).To(Equal(method))
}

func (client *MockRPCClient) AssertBatchCalledWith(method string, lengthOfBatch int) {
	Expect(client.lengthOfBatch).To(Equal(lengthOfBatch))
	for _, batch := range client.passedBatch {
		Expect(batch.Method).To(Equal(method))
	}
	Expect(client.passedMethod).To(Equal(method))
}