package vm

import (
	"bytes"
	"math/big"
	"strconv"
	"testing"

	"github.com/ethereum/go-ethereum/ethutil"
	"github.com/ethereum/go-ethereum/state"
	"github.com/ethereum/go-ethereum/tests/helper"
)

type Account struct {
	Balance string
	Code    string
	Nonce   string
	Storage map[string]string
}

func StateObjectFromAccount(addr string, account Account) *state.StateObject {
	obj := state.NewStateObject(ethutil.Hex2Bytes(addr))
	obj.SetBalance(ethutil.Big(account.Balance))

	if ethutil.IsHex(account.Code) {
		account.Code = account.Code[2:]
	}
	obj.Code = ethutil.Hex2Bytes(account.Code)
	obj.Nonce = ethutil.Big(account.Nonce).Uint64()

	return obj
}

type Env struct {
	CurrentCoinbase   string
	CurrentDifficulty string
	CurrentGasLimit   string
	CurrentNumber     string
	CurrentTimestamp  interface{}
	PreviousHash      string
}

type VmTest struct {
	Callcreates interface{}
	//Env         map[string]string
	Env         Env
	Exec        map[string]string
	Transaction map[string]string
	Gas         string
	Out         string
	Post        map[string]Account
	Pre         map[string]Account
}

func RunVmTest(p string, t *testing.T) {
	tests := make(map[string]VmTest)
	helper.CreateFileTests(t, p, &tests)

	for name, test := range tests {
		state := state.New(helper.NewTrie())
		for addr, account := range test.Pre {
			obj := StateObjectFromAccount(addr, account)
			state.SetStateObject(obj)
		}

		// XXX Yeah, yeah...
		env := make(map[string]string)
		env["currentCoinbase"] = test.Env.CurrentCoinbase
		env["currentDifficulty"] = test.Env.CurrentDifficulty
		env["currentGasLimit"] = test.Env.CurrentGasLimit
		env["currentNumber"] = test.Env.CurrentNumber
		env["previousHash"] = test.Env.PreviousHash
		if n, ok := test.Env.CurrentTimestamp.(float64); ok {
			env["currentTimestamp"] = strconv.Itoa(int(n))
		} else {
			env["currentTimestamp"] = test.Env.CurrentTimestamp.(string)
		}

		var (
			ret []byte
			gas *big.Int
			err error
		)

		if len(test.Exec) > 0 {
			ret, gas, err = helper.RunVm(state, env, test.Exec)
		} else {
			ret, gas, err = helper.RunState(state, env, test.Transaction)
		}

		// When an error is returned it doesn't always mean the tests fails.
		// Have to come up with some conditional failing mechanism.
		if err != nil {
			helper.Log.Infoln(err)
		}

		rexp := helper.FromHex(test.Out)
		if bytes.Compare(rexp, ret) != 0 {
			t.Errorf("%s's return failed. Expected %x, got %x\n", name, rexp, ret)
		}

		if len(test.Gas) > 0 {
			gexp := ethutil.Big(test.Gas)
			if gexp.Cmp(gas) != 0 {
				t.Errorf("%s's gas failed. Expected %v, got %v\n", name, gexp, gas)
			}
		}

		for addr, account := range test.Post {
			obj := state.GetStateObject(helper.FromHex(addr))
			for addr, value := range account.Storage {
				v := obj.GetState(helper.FromHex(addr)).Bytes()
				vexp := helper.FromHex(value)

				if bytes.Compare(v, vexp) != 0 {
					t.Errorf("%s's : (%x: %s) storage failed. Expected %x, got %x (%v %v)\n", name, obj.Address()[0:4], addr, vexp, v, ethutil.BigD(vexp), ethutil.BigD(v))
				}
			}
		}
	}
}

// I've created a new function for each tests so it's easier to identify where the problem lies if any of them fail.
func TestVMArithmetic(t *testing.T) {
	const fn = "../files/vmtests/vmArithmeticTest.json"
	RunVmTest(fn, t)
}

func TestBitwiseLogicOperation(t *testing.T) {
	const fn = "../files/vmtests/vmBitwiseLogicOperationTest.json"
	RunVmTest(fn, t)
}

func TestBlockInfo(t *testing.T) {
	const fn = "../files/vmtests/vmBlockInfoTest.json"
	RunVmTest(fn, t)
}

func TestEnvironmentalInfo(t *testing.T) {
	const fn = "../files/vmtests/vmEnvironmentalInfoTest.json"
	RunVmTest(fn, t)
}

func TestFlowOperation(t *testing.T) {
	const fn = "../files/vmtests/vmIOandFlowOperationsTest.json"
	RunVmTest(fn, t)
}

func TestPushDupSwap(t *testing.T) {
	const fn = "../files/vmtests/vmPushDupSwapTest.json"
	RunVmTest(fn, t)
}

func TestVMSha3(t *testing.T) {
	const fn = "../files/vmtests/vmSha3Test.json"
	RunVmTest(fn, t)
}

func TestVm(t *testing.T) {
	const fn = "../files/vmtests/vmtests.json"
	RunVmTest(fn, t)
}

func TestStateSystemOperations(t *testing.T) {
	const fn = "../files/StateTests/stSystemOperationsTest.json"
	RunVmTest(fn, t)
}

func TestStatePreCompiledContracts(t *testing.T) {
	const fn = "../files/StateTests/stPreCompiledContracts.json"
	RunVmTest(fn, t)
}

func TestStateRecursiveCreate(t *testing.T) {
	const fn = "../files/StateTests/stRecursiveCreate.json"
	RunVmTest(fn, t)
}

func TestStateSpecialTest(t *testing.T) {
	const fn = "../files/StateTests/stSpecialTest.json"
	RunVmTest(fn, t)
}