refactor: remove state API example

chain/events/state/state.go

@@ -1,57 +0,0 @@
-package state
-
-import (
-	"context"
-
-	"github.com/filecoin-project/lotus/chain/store"
-	"github.com/filecoin-project/specs-actors/actors/abi"
-
-	"github.com/filecoin-project/lotus/api"
-	"github.com/filecoin-project/lotus/chain/types"
-)
-
-type StateWatcher struct {
-}
-
-type WatcherAPI interface {
-	ChainNotify(context.Context) (<-chan []*api.HeadChange, error)
-}
-
-type UserData interface{}
-
-type DiffFunc func(ctx context.Context, oldState, newState *types.TipSet) (changed bool, user UserData, err error)
-
-type Callback func(ctx context.Context, oldState, newState *types.TipSet, events interface{})
-
-type RevertHandler func(ctx context.Context, ts *types.TipSet) error
-
-/*
-w := NewWatcher(api, OnActorChange(t04, OnDealStateChange(123)), cb)
-*/
-func NewWatcher(ctx context.Context, api WatcherAPI, d DiffFunc, apply Callback, revert RevertHandler, confidence, timeout abi.ChainEpoch) {
-	go func() {
-		notifs, err := api.ChainNotify(ctx)
-		if err != nil {
-			// bad
-			return
-		}
-
-		curTs := (<-notifs)[0].Val
-		d(ctx, curTs, curTs)
-
-		for {
-			select {
-			case update := <-notifs:
-				for i, change := range update {
-					switch change.Type {
-					case store.HCApply:
-						d(ctx, curTs, change.Val)
-					case store.HCRevert:
-
-					}
-				}
-			}
-		}
-
-	}()
-}