add todo.triggered to indicate should be set to todo

pttodo/todo.go

@@ -1,8 +1,16 @@
 package pttodo
 
+import "time"
+
 type Todo struct {
 	Todo     string
 	Detail   string   `yaml:",omitempty"`
 	TS       TS       `yaml:",omitempty"`
 	Schedule Schedule `yaml:",omitempty"`
 }
+
+func (todo Todo) Triggered() bool {
+	last := todo.TS
+	next, err := todo.Schedule.Next(last.time())
+	return err == nil && time.Now().After(next)
+}