package stmgr_test

import (
	"context"
	"fmt"
	"io"
	"testing"

	"github.com/filecoin-project/go-address"
	"github.com/filecoin-project/lotus/build"
	"github.com/filecoin-project/lotus/chain/actors"
	"github.com/filecoin-project/lotus/chain/actors/aerrors"
	"github.com/filecoin-project/lotus/chain/gen"
	"github.com/filecoin-project/lotus/chain/state"
	"github.com/filecoin-project/lotus/chain/stmgr"
	. "github.com/filecoin-project/lotus/chain/stmgr"
	"github.com/filecoin-project/lotus/chain/types"
	"github.com/filecoin-project/lotus/chain/vm"

	"github.com/ipfs/go-cid"
	hamt "github.com/ipfs/go-hamt-ipld"
	blockstore "github.com/ipfs/go-ipfs-blockstore"
	logging "github.com/ipfs/go-log"
	mh "github.com/multiformats/go-multihash"
	cbg "github.com/whyrusleeping/cbor-gen"
)

func init() {
	build.SectorSizes = []uint64{1024}
	build.MinimumMinerPower = 1024
}

const testForkHeight = 40

type testActor struct {
}

type testActorState struct {
	HasUpgraded uint64
}

func (tas *testActorState) MarshalCBOR(w io.Writer) error {
	return cbg.CborWriteHeader(w, cbg.MajUnsignedInt, tas.HasUpgraded)
}

func (tas *testActorState) UnmarshalCBOR(r io.Reader) error {
	t, v, err := cbg.CborReadHeader(r)
	if err != nil {
		return err
	}
	if t != cbg.MajUnsignedInt {
		return fmt.Errorf("wrong type in test actor state")
	}
	tas.HasUpgraded = v
	return nil
}

func (ta *testActor) Exports() []interface{} {
	return []interface{}{
		1: ta.Constructor,
		2: ta.TestMethod,
	}
}

func (ta *testActor) Constructor(act *types.Actor, vmctx types.VMContext, params *struct{}) ([]byte, aerrors.ActorError) {
	c, err := vmctx.Storage().Put(&testActorState{11})
	if err != nil {
		return nil, err
	}

	fmt.Println("NEW ACTOR ADDRESS IS: ", vmctx.Message().To.String())

	return nil, vmctx.Storage().Commit(actors.EmptyCBOR, c)
}

func (ta *testActor) TestMethod(act *types.Actor, vmctx types.VMContext, params *struct{}) ([]byte, aerrors.ActorError) {
	var st testActorState
	if err := vmctx.Storage().Get(vmctx.Storage().GetHead(), &st); err != nil {
		return nil, err
	}

	if vmctx.BlockHeight() > testForkHeight {
		if st.HasUpgraded != 55 {
			return nil, aerrors.Fatal("fork updating applied in wrong order")
		}
	} else {
		if st.HasUpgraded != 11 {
			return nil, aerrors.Fatal("fork updating happened too early")
		}
	}

	return nil, nil
}

func TestForkHeightTriggers(t *testing.T) {
	logging.SetAllLoggers(logging.LevelInfo)

	ctx := context.TODO()

	cg, err := gen.NewGenerator()
	if err != nil {
		t.Fatal(err)
	}

	sm := NewStateManager(cg.ChainStore())

	inv := vm.NewInvoker()

	pref := cid.NewPrefixV1(cid.Raw, mh.IDENTITY)
	actcid, err := pref.Sum([]byte("testactor"))
	if err != nil {
		t.Fatal(err)
	}

	actors.BuiltInActors[actcid] = true

	// predicting the address here... may break if other assumptions change
	taddr, err := address.NewIDAddress(1000)
	if err != nil {
		t.Fatal(err)
	}

	stmgr.ForksAtHeight[testForkHeight] = func(ctx context.Context, sm *StateManager, pstate cid.Cid) (cid.Cid, error) {
		cst := hamt.CSTFromBstore(sm.ChainStore().Blockstore())
		st, err := state.LoadStateTree(cst, pstate)
		if err != nil {
			return cid.Undef, err
		}

		act, err := st.GetActor(taddr)
		if err != nil {
			return cid.Undef, err
		}

		var tas testActorState
		if err := cst.Get(ctx, act.Head, &tas); err != nil {
			return cid.Undef, err
		}

		tas.HasUpgraded = 55

		ns, err := cst.Put(ctx, &tas)
		if err != nil {
			return cid.Undef, err
		}

		act.Head = ns

		if err := st.SetActor(taddr, act); err != nil {
			return cid.Undef, err
		}

		return st.Flush(ctx)
	}

	inv.Register(actcid, &testActor{}, &testActorState{})
	sm.SetVMConstructor(func(c cid.Cid, h uint64, r vm.Rand, a address.Address, b blockstore.Blockstore, s *types.VMSyscalls) (*vm.VM, error) {
		nvm, err := vm.NewVM(c, h, r, a, b, s)
		if err != nil {
			return nil, err
		}
		nvm.SetInvoker(inv)
		return nvm, nil
	})

	cg.SetStateManager(sm)

	var msgs []*types.SignedMessage

	enc, err := actors.SerializeParams(&actors.ExecParams{Code: actcid})
	if err != nil {
		t.Fatal(err)
	}

	m := &types.Message{
		From:     cg.Banker(),
		To:       actors.InitAddress,
		Method:   actors.IAMethods.Exec,
		Params:   enc,
		GasLimit: types.NewInt(10000),
		GasPrice: types.NewInt(0),
	}
	sig, err := cg.Wallet().Sign(ctx, cg.Banker(), m.Cid().Bytes())
	if err != nil {
		t.Fatal(err)
	}
	msgs = append(msgs, &types.SignedMessage{
		Signature: *sig,
		Message:   *m,
	})

	nonce := uint64(1)
	cg.GetMessages = func(cg *gen.ChainGen) ([]*types.SignedMessage, error) {
		if len(msgs) > 0 {
			fmt.Println("added construct method")
			m := msgs
			msgs = nil
			return m, nil
		}

		m := &types.Message{
			From:     cg.Banker(),
			To:       taddr,
			Method:   2,
			Params:   nil,
			Nonce:    nonce,
			GasLimit: types.NewInt(10000),
			GasPrice: types.NewInt(0),
		}
		nonce++

		sig, err := cg.Wallet().Sign(ctx, cg.Banker(), m.Cid().Bytes())
		if err != nil {
			return nil, err
		}

		return []*types.SignedMessage{
			&types.SignedMessage{
				Signature: *sig,
				Message:   *m,
			},
		}, nil
	}

	for i := 0; i < 50; i++ {
		_, err = cg.NextTipSet()
		if err != nil {
			t.Fatal(err)
		}
	}
}