package net.sourceforge.fenixedu.domain.system;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Collections;
import java.util.Comparator;
import java.util.Set;
import java.util.SortedSet;

import net.sourceforge.fenixedu.domain.RootDomainObject;
import net.sourceforge.fenixedu.domain.exceptions.DomainException;
import net.sourceforge.fenixedu.domain.util.FactoryExecutor;
import net.sourceforge.fenixedu.util.ByteArray;

import org.joda.time.DateTime;
import org.joda.time.Period;

import pt.utl.ist.fenix.tools.util.CollectionUtils;

public class CronScriptState extends CronScriptState_Base {

    public static final Comparator<CronScriptState> COMPARATOR_BY_ABSOLUTE_EXECUTION_ORDER = new Comparator<CronScriptState>() {

	@Override
	public int compare(CronScriptState o1, CronScriptState o2) {
	    return o1.getAbsoluteExecutionOrder().compareTo(o2.getAbsoluteExecutionOrder());
	}

    };

    public static final Comparator<CronScriptState> COMPARATOR_BY_CRON_SCRIPT_CLASSNAME = new Comparator<CronScriptState>() {

	@Override
	public int compare(CronScriptState o1, CronScriptState o2) {
	    return o1.getCronScriptClassname().compareTo(o2.getCronScriptClassname());
	}

    };

    private transient Class cronScriptClass = null;

    public static class RunNowExecutor implements FactoryExecutor {

	private final CronScriptState cronScriptState;

	public RunNowExecutor(final CronScriptState cronScriptState) {
	    this.cronScriptState = cronScriptState;
	}

	@Override
	public Object execute() {
	    cronScriptState.setRunNow(Boolean.TRUE);
	    return null;
	}

    }

    public CronScriptState(final Class cronScriptClass, final Period invocationPeriod, final WhenToSendEmail whenToSendEmail,
	    final String emails) {
	super();
	setRootDomainObject(RootDomainObject.getInstance());
	setCronScriptClassname(cronScriptClass.getName());
	this.cronScriptClass = cronScriptClass;
	// TODO : set absoluteExecutionOrder
	setRegistrationDate(new DateTime());
	setActive(Boolean.TRUE);
	setIsCurrentlyRunning(Boolean.FALSE);
	setInvocationPeriod(invocationPeriod);
	setRunNow(Boolean.FALSE);
    }

    public void serializeContext(final Serializable context) {
	ByteArray byteArray;
	if (context != null) {
	    final ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
	    try {
		final ObjectOutputStream objectOutputStream = new ObjectOutputStream(byteArrayOutputStream);
		objectOutputStream.writeObject(context);
		objectOutputStream.close();
		byteArray = new ByteArray(byteArrayOutputStream.toByteArray());
	    } catch (final Exception exception) {
		byteArray = null;
	    }
	} else {
	    byteArray = null;
	}
	setContext(byteArray);
    }

    public Serializable deserializeContext() throws IOException, ClassNotFoundException {
	if (getContext() == null) {
	    return null;
	}
	final byte[] byteArray = getContext().getBytes();
	final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(byteArray);
	final ObjectInputStream objectInputStream = new ObjectInputStream(byteArrayInputStream);
	final Serializable context = (Serializable) objectInputStream.readObject();
	objectInputStream.close();
	return context;
    }

    public Class getCronScriptClass() throws ClassNotFoundException {
	if (cronScriptClass == null) {
	    cronScriptClass = Class.forName(getCronScriptClassname());
	}
	return cronScriptClass;
    }

    public CronScriptInvocation getLastCronScriptInvocation() {
	final Set<CronScriptInvocation> invocationSet = getCronScriptInvocationsSet();
	return invocationSet.isEmpty() ? null : Collections.max(invocationSet, CronScriptInvocation.COMPARATOR_BY_START_TIME);
    }

    public boolean shouldBeRunNow() {
	if (getActive().booleanValue()) {
	    final Period invocationPeriod = getInvocationPeriod();
	    final CronScriptInvocation lastCronScriptInvocation = getLastCronScriptInvocation();
	    final Boolean runNow = getRunNow();
	    return lastCronScriptInvocation == null || (runNow != null && runNow.booleanValue())
		    || lastCronScriptInvocation.hasReachedNextInvocationTime(invocationPeriod);
	}
	return false;
    }

    public String getInvocationPeriodString() {
	if (getInvocationPeriod().getMinutes() > 0)
	    return "every " + getInvocationPeriod().getMinutes() + " minutes";
	if (getInvocationPeriod().getHours() > 0)
	    return "every " + getInvocationPeriod().getHours() + " hours";
	if (getInvocationPeriod().getDays() > 0)
	    return "every " + getInvocationPeriod().getDays() + " days";
	if (getInvocationPeriod().getWeeks() > 0)
	    return "every " + getInvocationPeriod().getWeeks() + " weeks";
	if (getInvocationPeriod().getMonths() > 0)
	    return "every " + getInvocationPeriod().getMonths() + " months";
	if (getInvocationPeriod().getYears() > 0)
	    return "every " + getInvocationPeriod().getYears() + " years";
	throw new DomainException("error.unknown.period.type");
    }

    public DateTime getLastInvocationStartTime() {
	final CronScriptInvocation lastCronScriptInvocation = getLastCronScriptInvocation();
	return lastCronScriptInvocation == null ? null : lastCronScriptInvocation.getStartTime();
    }

    public DateTime getLastInvocationEndTime() {
	final CronScriptInvocation lastCronScriptInvocation = getLastCronScriptInvocation();
	return lastCronScriptInvocation == null ? null : lastCronScriptInvocation.getEndTime();
    }

    public Boolean getSuccessful() {
	final CronScriptInvocation lastCronScriptInvocation = getLastCronScriptInvocation();
	return lastCronScriptInvocation == null ? null : lastCronScriptInvocation.getSuccessful();
    }

    public DateTime getNextExpectedInvocationTime() {
	final CronScriptInvocation lastCronScriptInvocation = getLastCronScriptInvocation();
	return lastCronScriptInvocation == null ? null : lastCronScriptInvocation.getStartTime().plus(getInvocationPeriod());
    }

    public SortedSet<CronScriptInvocation> getCronScriptInvocationsSetSortedByInvocationStartTime() {
	return CollectionUtils.constructSortedSet(getCronScriptInvocationsSet(), CronScriptInvocation.COMPARATOR_BY_START_TIME);
    }

}