package simulation_test

import (
	"math/rand"
	"testing"
	"time"

	"github.com/stretchr/testify/require"
	abci "github.com/tendermint/tendermint/abci/types"

	"github.com/cosmos/cosmos-sdk/simapp"
	simappparams "github.com/cosmos/cosmos-sdk/simapp/params"
	sdk "github.com/cosmos/cosmos-sdk/types"
	simtypes "github.com/cosmos/cosmos-sdk/types/simulation"
	distrtypes "github.com/cosmos/cosmos-sdk/x/distribution/types"
	minttypes "github.com/cosmos/cosmos-sdk/x/mint/types"
	"github.com/cosmos/cosmos-sdk/x/slashing/simulation"
	"github.com/cosmos/cosmos-sdk/x/slashing/types"
	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"
)

// TestWeightedOperations tests the weights of the operations.
func TestWeightedOperations(t *testing.T) {
	app, ctx := createTestApp(false)
	ctx.WithChainID("test-chain")

	cdc := app.LegacyAmino()
	appParams := make(simtypes.AppParams)

	s := rand.NewSource(1)
	r := rand.New(s)
	accs := simtypes.RandomAccounts(r, 3)

	expected := []struct {
		weight     int
		opMsgRoute string
		opMsgName  string
	}{{simappparams.DefaultWeightMsgUnjail, types.ModuleName, types.TypeMsgUnjail}}

	weightesOps := simulation.WeightedOperations(appParams, cdc, app.AccountKeeper, app.BankKeeper, app.SlashingKeeper, app.StakingKeeper)
	for i, w := range weightesOps {
		operationMsg, _, _ := w.Op()(r, app.BaseApp, ctx, accs, ctx.ChainID())
		// the following checks are very much dependent from the ordering of the output given
		// by WeightedOperations. if the ordering in WeightedOperations changes some tests
		// will fail
		require.Equal(t, expected[i].weight, w.Weight(), "weight should be the same")
		require.Equal(t, expected[i].opMsgRoute, operationMsg.Route, "route should be the same")
		require.Equal(t, expected[i].opMsgName, operationMsg.Name, "operation Msg name should be the same")
	}
}

// TestSimulateMsgUnjail tests the normal scenario of a valid message of type types.MsgUnjail.
// Abonormal scenarios, where the message is created by an errors, are not tested here.
func TestSimulateMsgUnjail(t *testing.T) {
	app, ctx := createTestApp(false)
	blockTime := time.Now().UTC()
	ctx = ctx.WithBlockTime(blockTime)

	// setup 3 accounts
	s := rand.NewSource(1)
	r := rand.New(s)
	accounts := getTestingAccounts(t, r, app, ctx, 3)

	// setup accounts[0] as validator0
	validator0 := getTestingValidator0(t, app, ctx, accounts)

	// setup validator0 by consensus address
	app.StakingKeeper.SetValidatorByConsAddr(ctx, validator0)
	val0ConsAddress := sdk.ConsAddress(validator0.GetConsPubKey().Address())
	info := types.NewValidatorSigningInfo(val0ConsAddress, int64(4), int64(3),
		time.Unix(2, 0), false, int64(10))
	app.SlashingKeeper.SetValidatorSigningInfo(ctx, val0ConsAddress, info)

	// put validator0 in jail
	app.StakingKeeper.Jail(ctx, val0ConsAddress)

	// setup self delegation
	delTokens := sdk.TokensFromConsensusPower(2)
	validator0, issuedShares := validator0.AddTokensFromDel(delTokens)
	val0AccAddress := sdk.AccAddress(validator0.OperatorAddress.Bytes())
	selfDelegation := stakingtypes.NewDelegation(val0AccAddress, validator0.OperatorAddress, issuedShares)
	app.StakingKeeper.SetDelegation(ctx, selfDelegation)
	app.DistrKeeper.SetDelegatorStartingInfo(ctx, validator0.OperatorAddress, val0AccAddress, distrtypes.NewDelegatorStartingInfo(2, sdk.OneDec(), 200))

	// begin a new block
	app.BeginBlock(abci.RequestBeginBlock{Header: abci.Header{Height: app.LastBlockHeight() + 1, AppHash: app.LastCommitID().Hash, Time: blockTime}})

	// execute operation
	op := simulation.SimulateMsgUnjail(app.AccountKeeper, app.BankKeeper, app.SlashingKeeper, app.StakingKeeper)
	operationMsg, futureOperations, err := op(r, app.BaseApp, ctx, accounts, "")
	require.NoError(t, err)

	var msg types.MsgUnjail
	types.ModuleCdc.UnmarshalJSON(operationMsg.Msg, &msg)

	require.True(t, operationMsg.OK)
	require.Equal(t, types.TypeMsgUnjail, msg.Type())
	require.Equal(t, "cosmosvaloper1tnh2q55v8wyygtt9srz5safamzdengsn9dsd7z", msg.GetValidatorAddr().String())
	require.Len(t, futureOperations, 0)
}

// returns context and an app with updated mint keeper
func createTestApp(isCheckTx bool) (*simapp.SimApp, sdk.Context) {
	app := simapp.Setup(isCheckTx)

	ctx := app.BaseApp.NewContext(isCheckTx, abci.Header{})
	app.MintKeeper.SetParams(ctx, minttypes.DefaultParams())
	app.MintKeeper.SetMinter(ctx, minttypes.DefaultInitialMinter())

	return app, ctx
}

func getTestingAccounts(t *testing.T, r *rand.Rand, app *simapp.SimApp, ctx sdk.Context, n int) []simtypes.Account {
	accounts := simtypes.RandomAccounts(r, n)

	initAmt := sdk.TokensFromConsensusPower(200)
	initCoins := sdk.NewCoins(sdk.NewCoin(sdk.DefaultBondDenom, initAmt))

	// add coins to the accounts
	for _, account := range accounts {
		acc := app.AccountKeeper.NewAccountWithAddress(ctx, account.Address)
		app.AccountKeeper.SetAccount(ctx, acc)
		err := app.BankKeeper.SetBalances(ctx, account.Address, initCoins)
		require.NoError(t, err)
	}

	return accounts
}

func getTestingValidator0(t *testing.T, app *simapp.SimApp, ctx sdk.Context, accounts []simtypes.Account) stakingtypes.Validator {
	commission0 := stakingtypes.NewCommission(sdk.ZeroDec(), sdk.OneDec(), sdk.OneDec())
	return getTestingValidator(t, app, ctx, accounts, commission0, 0)
}

func getTestingValidator(t *testing.T, app *simapp.SimApp, ctx sdk.Context, accounts []simtypes.Account, commission stakingtypes.Commission, n int) stakingtypes.Validator {
	account := accounts[n]
	valPubKey := account.PubKey
	valAddr := sdk.ValAddress(account.PubKey.Address().Bytes())
	validator := stakingtypes.NewValidator(valAddr, valPubKey, stakingtypes.Description{})
	validator, err := validator.SetInitialCommission(commission)
	require.NoError(t, err)

	validator.DelegatorShares = sdk.NewDec(100)
	validator.Tokens = sdk.NewInt(1000000)

	app.StakingKeeper.SetValidator(ctx, validator)

	return validator
}