package timer import ( "github.com/nspcc-dev/neo-go/pkg/interop" "github.com/nspcc-dev/neo-go/pkg/interop/binary" "github.com/nspcc-dev/neo-go/pkg/interop/contract" "github.com/nspcc-dev/neo-go/pkg/interop/runtime" "github.com/nspcc-dev/neo-go/pkg/interop/storage" "github.com/nspcc-dev/neo-go/pkg/interop/util" ) const defaultTicks = 3 const mgmtKey = "mgmt" var ( // ctx holds storage context for contract methods ctx storage.Context // Check if the invoker of the contract is the specified owner owner = util.FromAddress("NULwe3UAHckN2fzNdcVg31tDiaYtMDwANt") // ticksKey is a storage key for ticks counter ticksKey = []byte("ticks") ) func init() { ctx = storage.GetContext() } func _deploy(isUpdate bool) { if isUpdate { ticksLeft := storage.Get(ctx, ticksKey).(int) + 1 storage.Put(ctx, ticksKey, ticksLeft) runtime.Log("One more tick is added.") return } sh := runtime.GetCallingScriptHash() storage.Put(ctx, mgmtKey, sh) storage.Put(ctx, ticksKey, defaultTicks) i := binary.Itoa(defaultTicks, 10) runtime.Log("Timer set to " + i + " ticks.") } // Migrate migrates the contract. func Migrate(script []byte, manifest []byte) bool { if !runtime.CheckWitness(owner) { runtime.Log("Only owner is allowed to update the contract.") return false } mgmt := storage.Get(ctx, mgmtKey).(interop.Hash160) contract.Call(mgmt, "update", script, manifest) runtime.Log("Contract updated.") return true } // Tick decrement ticks count and checks whether the timer is fired. func Tick() bool { runtime.Log("Tick-tock.") ticksLeft := storage.Get(ctx, ticksKey) ticksLeft = ticksLeft.(int) - 1 if ticksLeft == 0 { runtime.Log("Fired!") return contract.Call(runtime.GetExecutingScriptHash(), "selfDestroy").(bool) } storage.Put(ctx, ticksKey, ticksLeft) i := binary.Itoa(ticksLeft.(int), 10) runtime.Log(i + " ticks left.") return true } // SelfDestroy destroys the contract. func SelfDestroy() bool { if !(runtime.CheckWitness(owner) || runtime.CheckWitness(runtime.GetExecutingScriptHash())) { runtime.Log("Only owner or the contract itself are allowed to destroy the contract.") return false } mgmt := storage.Get(ctx, mgmtKey).(interop.Hash160) contract.Call(mgmt, "destroy") runtime.Log("Destroyed.") return true }