package index

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

	"github.com/stretchr/testify/require"

	"github.com/filecoin-project/go-address"
	"github.com/filecoin-project/go-state-types/abi"

	"github.com/filecoin-project/lotus/chain/types"
)

func TestGC(t *testing.T) {
	ctx := context.Background()
	seed := time.Now().UnixNano()
	t.Logf("seed: %d", seed)
	rng := pseudo.New(pseudo.NewSource(seed))
	headHeight := abi.ChainEpoch(60)
	si, _, cs := setupWithHeadIndexed(t, headHeight, rng)
	t.Cleanup(func() { _ = si.Close() })

	si.gcRetentionEpochs = 20

	ev1 := fakeEvent(
		abi.ActorID(1),
		[]kv{
			{k: "type", v: []byte("approval")},
			{k: "signer", v: []byte("addr1")},
		},
		[]kv{
			{k: "amount", v: []byte("2988181")},
		},
	)

	ev2 := fakeEvent(
		abi.ActorID(2),
		[]kv{
			{k: "type", v: []byte("approval")},
			{k: "signer", v: []byte("addr2")},
		},
		[]kv{
			{k: "amount", v: []byte("2988181")},
		},
	)

	events := []types.Event{*ev1, *ev2}

	fm := fakeMessage(address.TestAddress, address.TestAddress)
	em1 := executedMessage{
		msg: fm,
		evs: events,
	}

	si.SetActorToDelegatedAddresFunc(func(ctx context.Context, emitter abi.ActorID, ts *types.TipSet) (address.Address, bool) {
		idAddr, err := address.NewIDAddress(uint64(emitter))
		if err != nil {
			return address.Undef, false
		}

		return idAddr, true
	})

	si.setExecutedMessagesLoaderFunc(func(ctx context.Context, cs ChainStore, msgTs, rctTs *types.TipSet) ([]executedMessage, error) {
		if msgTs.Height() == 1 {
			return []executedMessage{em1}, nil
		}
		return nil, nil
	})

	// Create a fake tipset at height 1
	fakeTipSet1 := fakeTipSet(t, rng, 1, nil)
	fakeTipSet2 := fakeTipSet(t, rng, 10, nil)
	fakeTipSet3 := fakeTipSet(t, rng, 50, nil)

	// Set the dummy chainstore to return this tipset for height 1
	cs.SetTipsetByHeightAndKey(1, fakeTipSet1.Key(), fakeTipSet1)  // empty DB
	cs.SetTipsetByHeightAndKey(10, fakeTipSet2.Key(), fakeTipSet2) // empty DB
	cs.SetTipsetByHeightAndKey(50, fakeTipSet3.Key(), fakeTipSet3) // empty DB
	cs.SetTipSetByCid(t, fakeTipSet1)
	cs.SetTipSetByCid(t, fakeTipSet2)
	cs.SetTipSetByCid(t, fakeTipSet3)

	cs.SetMessagesForTipset(fakeTipSet1, []types.ChainMsg{fm})

	// index tipset and events
	require.NoError(t, si.Apply(ctx, fakeTipSet1, fakeTipSet2))
	require.NoError(t, si.Apply(ctx, fakeTipSet2, fakeTipSet3))

	// getLogs works for height 1
	filter := &EventFilter{
		MinHeight: 1,
		MaxHeight: 1,
	}
	ces, err := si.GetEventsForFilter(ctx, filter)
	require.NoError(t, err)
	require.Len(t, ces, 2)

	si.gc(ctx)

	// getLogs does not work for height 1
	_, err = si.GetEventsForFilter(ctx, filter)
	require.Error(t, err)

	// Verify that the tipset at height 1 is removed
	var count int
	err = si.db.QueryRow("SELECT COUNT(*) FROM tipset_message WHERE height = 1").Scan(&count)
	require.NoError(t, err)
	require.Equal(t, 0, count)

	// Verify that the tipset at height 10 is not removed
	err = si.db.QueryRow("SELECT COUNT(*) FROM tipset_message WHERE height = 10").Scan(&count)
	require.NoError(t, err)
	require.Equal(t, 0, count)

	// Verify that the tipset at height 50 is not removed
	err = si.db.QueryRow("SELECT COUNT(*) FROM tipset_message WHERE height = 50").Scan(&count)
	require.NoError(t, err)
	require.Equal(t, 1, count)
}