package opencm.domain.service;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import java.util.Stack;

import opencm.domain.interfaces.ConsultaRepository;
import opencm.domain.model.Consulta;
import opencm.domain.model.HorarioAtendimento;

import org.joda.time.Interval;

public final class AgendamentoService {

	private ConsultaRepository consultaRepository;
	
	public AgendamentoService(ConsultaRepository consultaRepository) {
		this.consultaRepository = consultaRepository;
	}

	private List<Interval> consultaIntervals(List<Consulta> consultas) {
		List<Interval> result = new ArrayList<Interval>();
		
		for (Consulta consulta : consultas) {
			result.add(new Interval(consulta.getInicio(), consulta.getDuracao()));			
		}
		
		return mergeIntervals(result);
	}
	
	private List<Interval> atendimentoIntervals(List<HorarioAtendimento> horarios) {
		List<Interval> result = new ArrayList<Interval>();
		
		for (HorarioAtendimento horario : horarios) {
			result.add(new Interval(horario.getHoraInicial().toDateTimeToday(), horario.getHoraFinal().toDateTimeToday()));
		}
		
		return mergeIntervals(result);
	}
	
	private List<Interval> mergeIntervals(List<Interval> intervals) {
		List<Interval> sortedIntervals = new ArrayList<Interval>(intervals);
		
		Collections.sort(sortedIntervals, new Comparator<Interval>() { public int compare(Interval a, Interval b) {
				return a.getStart().compareTo(b.getStart());
		}});
		
		Iterator<Interval> sortedIntervalsIt = sortedIntervals.iterator();
		
		Stack<Interval> mergedIntervals = new Stack<Interval>();
		
		while (sortedIntervalsIt.hasNext()) {
			Interval current = sortedIntervalsIt.next();
			
			if (!mergedIntervals.empty() && current.abuts(mergedIntervals.peek())) {
				mergedIntervals.push(new Interval(mergedIntervals.pop().getStart(), current.getEnd()));
			} else {
				mergedIntervals.push(current);
			}
		}

		return mergedIntervals;
	}
}