// Copyright 2018 Vulcanize
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package every_block_test

import (
	"github.com/ethereum/go-ethereum/ethclient"
	"github.com/ethereum/go-ethereum/rpc"
	. "github.com/onsi/ginkgo"
	. "github.com/onsi/gomega"
	"github.com/vulcanize/vulcanizedb/examples/constants"
	"github.com/vulcanize/vulcanizedb/examples/erc20_watcher/every_block"
	"github.com/vulcanize/vulcanizedb/examples/mocks"
	"github.com/vulcanize/vulcanizedb/pkg/geth"
	"github.com/vulcanize/vulcanizedb/pkg/geth/client"
	rpc2 "github.com/vulcanize/vulcanizedb/pkg/geth/converters/rpc"
	"github.com/vulcanize/vulcanizedb/pkg/geth/node"
	"math/big"
)

var _ = Describe("ERC20 Fetcher", func() {
	blockNumber := int64(5502914)
	infuraIPC := "https://mainnet.infura.io/J5Vd2fRtGsw0zZ0Ov3BL"
	var errorFetcher every_block.Fetcher
	var realFetcher every_block.Fetcher
	var testFetcher every_block.Fetcher
	var fakeBlockchain *mocks.Blockchain
	var testAbi string
	var testContractAddress string

	BeforeEach(func() {
		rpcClient, err := rpc.Dial(infuraIPC)
		Expect(err).NotTo(HaveOccurred())
		ethClient := ethclient.NewClient(rpcClient)
		blockChainClient := client.NewClient(ethClient)
		clientWrapper := node.ClientWrapper{
			ContextCaller: rpcClient,
			IPCPath:       infuraIPC,
		}
		node := node.MakeNode(clientWrapper)
		transactionConverter := rpc2.NewRpcTransactionConverter(ethClient)
		realBlockChain := geth.NewBlockChain(blockChainClient, node, transactionConverter)
		realFetcher = every_block.NewFetcher(realBlockChain)
		fakeBlockchain = &mocks.Blockchain{}
		testFetcher = every_block.NewFetcher(fakeBlockchain)
		testAbi = "testAbi"
		testContractAddress = "testContractAddress"

		errorBlockchain := &mocks.FailureBlockchain{}
		errorFetcher = every_block.NewFetcher(errorBlockchain)
	})

	Describe("FetchSupplyOf", func() {
		It("fetches data from the blockchain with the correct arguments", func() {
			_, err := testFetcher.FetchSupplyOf(testAbi, testContractAddress, blockNumber)

			Expect(err).NotTo(HaveOccurred())
			Expect(fakeBlockchain.FetchedAbi).To(Equal(testAbi))
			Expect(fakeBlockchain.FetchedContractAddress).To(Equal(testContractAddress))
			Expect(fakeBlockchain.FetchedMethod).To(Equal("totalSupply"))
			Expect(fakeBlockchain.FetchedMethodArg).To(BeNil())
			expectedResult := big.Int{}
			expected := &expectedResult
			Expect(fakeBlockchain.FetchedResult).To(Equal(&expected))
			Expect(fakeBlockchain.FetchedBlockNumber).To(Equal(blockNumber))
		})

		It("fetches a token's total supply at the given block height", func() {
			result, err := realFetcher.FetchSupplyOf(constants.DaiAbiString, constants.DaiContractAddress, blockNumber)

			Expect(err).NotTo(HaveOccurred())
			expectedResult := big.Int{}
			expectedResult.SetString("27647235749155415536952630", 10)
			Expect(result).To(Equal(expectedResult))
		})

		It("returns an error if the call to the blockchain fails", func() {
			result, err := errorFetcher.FetchSupplyOf("", "", 0)

			Expect(result.String()).To(Equal("0"))
			Expect(err).To(HaveOccurred())
			Expect(err.Error()).To(ContainSubstring("totalSupply"))
			Expect(err.Error()).To(ContainSubstring(mocks.TestError.Error()))
		})
	})
})