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;
    }
}