class TimeInference {

	// This function replaces all Sentences that have a past sentence by their immediately past value:
	static applyTimePast(sc:SentenceContainer) : SentenceContainer
	{
		let newsc:SentenceContainer = new SentenceContainer();
		console.log("TimeInference.applyTimePast!");
		for(let s of sc.previousSentencesWithNoCurrentSentence) {
//			console.log("from previousSentencesWithNoCurrentSentence: " + s.sentence);
			// we have to use "addStateSentenceIfNew" here, since some of these might overwrite each other...
			newsc.addStateSentenceIfNew(s.sentence, s.provenance, s.activation, s.time);
		}

		for(let s of sc.plainSentenceList) {
			if (s.previousInTime == null) {
				newsc.addSentence(s.sentence, s.provenance, s.activation, s.time);
			} else {
//				console.log("from plainSentenceList.previousInTime: " + s.previousInTime.sentence);
				newsc.addSentence(s.previousInTime.sentence, s.previousInTime.provenance, s.previousInTime.activation, s.previousInTime.time);
			}
		}

		return newsc;
	}


	static timeMatch(current:number, start:number, end:number, timeTerm:Term) : boolean
	{
/*
		// TODO: 
	    <sort name="time.at" super="time,relation"/>
	    <sort name="time.subsequently" super="time.later,relation"/>
	    <sort name="time.today" super="time.now"/>
	    <sort name="time.yesterday" super="time.past"/>
	    <sort name="time.date" super="time"/>
*/
		if (timeTerm.functor.name == "time.past") {
			if (start < current) return true;
			return false;
		} else if (timeTerm.functor.name == "time.present" ||
			 	   timeTerm.functor.name == "time.now") {
			if (start <= current &&
				(end == null || end > current)) return true;
		} else if (timeTerm.functor.name == "time.future" ||
				   timeTerm.functor.name == "time.later") {
			if (end == null || end > current) return true;
		} else if (timeTerm.functor.name == "time.today") {
			let dayStart:number = Math.floor(current / (60*60*24)) * 60*60*24;
			let dayEnd:number = dayStart + 60*60*24;
			if (start < dayEnd &&
				(end == null || end >= dayStart)) return true;
		} else if (timeTerm.functor.name == "time.yesterday") {
			let dayStart:number = (Math.floor(current / (60*60*24)) - 1) * 60*60*24;
			let dayEnd:number = dayStart + 60*60*24;
			if (start < dayEnd &&
				(end == null || end >= dayStart)) return true;
		}
		return false;
	}
}