package net.sourceforge.fenixedu.presentationTier.Action.manager;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import net.sourceforge.fenixedu.applicationTier.IUserView;
import net.sourceforge.fenixedu.dataTransferObject.research.result.ExecutionYearIntervalBean;
import net.sourceforge.fenixedu.domain.ExecutionYear;
import net.sourceforge.fenixedu.domain.Item;
import net.sourceforge.fenixedu.domain.Section;
import net.sourceforge.fenixedu.domain.contents.Content;
import net.sourceforge.fenixedu.domain.functionalities.FunctionalityContext;
import net.sourceforge.fenixedu.presentationTier.Action.base.FenixDispatchAction;
import net.sourceforge.fenixedu.presentationTier.Action.publico.ProtectedItem;
import net.sourceforge.fenixedu.presentationTier.Action.publico.SimpleFunctionalityContext;
import net.sourceforge.fenixedu.presentationTier.Action.utils.RequestUtils;

import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;

/**
 * Generic action to coordinate the visualization of a website.
 * 
 * 
 * @author cfgi
 */
public abstract class SiteVisualizationDA extends FenixDispatchAction {

    @Override
    public ActionForward execute(ActionMapping mapping, ActionForm actionForm, HttpServletRequest request,
	    HttpServletResponse response) throws Exception {
	String directLinkContext = getDirectLinkContext(request);
	if (directLinkContext != null) {
	    request.setAttribute("directLinkContext", directLinkContext);
	}

	setSectionBreadCrumbs(request);
	return super.execute(mapping, actionForm, request, response);
    }

    public ActionForward item(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response)
	    throws IOException {
	Item item = selectItem(request);

	if (item == null) {
	    return getSiteDefaultView(mapping, form, request, response);
	}

	IUserView userView = prepareUserView(request);
	FunctionalityContext context = prepareSectionContext(request);

	if (item.isAvailable(context)) {
	    return mapping.findForward("site-item");
	} else {
	    if (isAuthenticated(userView)) {
		return mapping.findForward("site-item-deny");
	    } else {
		return mapping.findForward("site-item-adviseLogin");
	    }
	}
    }

    public ActionForward section(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response)
	    throws IOException {
	Section section = selectSection(request);

	if (section == null) {
	    return getSiteDefaultView(mapping, form, request, response);
	}

	IUserView userView = prepareUserView(request);
	FunctionalityContext context = prepareSectionContext(request);

	if (section.isAvailable(context)) {
	    prepareProtectedItems(request, userView, section.getOrderedItems(), context);
	    return mapping.findForward("site-section");
	} else {
	    if (isAuthenticated(userView)) {
		return mapping.findForward("site-section-deny");
	    } else {
		return mapping.findForward("site-section-adviseLogin");
	    }
	}
    }

    public ActionForward itemWithLogin(ActionMapping mapping, ActionForm form, HttpServletRequest request,
	    HttpServletResponse response) throws IOException {
	IUserView userView = getUserView(request);

	if (!isAuthenticated(userView)) {
	    RequestUtils.sendLoginRedirect(request, response);
	    return null;
	} else {
	    return item(mapping, form, request, response);
	}
    }

    public ActionForward sectionWithLogin(ActionMapping mapping, ActionForm form, HttpServletRequest request,
	    HttpServletResponse response) throws IOException {
	IUserView userView = getUserView(request);

	if (!isAuthenticated(userView)) {
	    RequestUtils.sendLoginRedirect(request, response);
	    return null;
	} else {
	    return section(mapping, form, request, response);
	}
    }

    private void prepareProtectedItems(HttpServletRequest request, IUserView userView, Collection<Item> items,
	    FunctionalityContext context) {
	List<ProtectedItem> protectedItems = setupItems(request, context, items);

	if (!isAuthenticated(userView) && hasRestrictedItems(protectedItems)) {
	    request.setAttribute("hasRestrictedItems", true);
	}
    }

    private boolean hasRestrictedItems(List<ProtectedItem> protectedItems) {
	for (ProtectedItem item : protectedItems) {
	    if (!item.isAvailable()) {
		return true;
	    }
	}

	return false;
    }

    private List<ProtectedItem> setupItems(HttpServletRequest request, FunctionalityContext context, Collection<Item> items) {
	List<ProtectedItem> protectedItems = new ArrayList<ProtectedItem>();
	for (Item item : items) {
	    if (item.getVisible()) {
		protectedItems.add(new ProtectedItem(context, item));
	    }
	}

	request.setAttribute("protectedItems", protectedItems);
	return protectedItems;
    }

    private IUserView prepareUserView(HttpServletRequest request) {
	IUserView userView = getUserView(request);
	request.setAttribute("logged", isAuthenticated(userView));

	return userView;
    }

    private FunctionalityContext prepareSectionContext(HttpServletRequest request) {
	FunctionalityContext context = new SimpleFunctionalityContext(request);
	request.setAttribute("context", context);
	return context;
    }

    private boolean isAuthenticated(IUserView userView) {
	return userView != null;
    }

    protected Section selectSection(HttpServletRequest request) {
	return selectSection(request, getSection(request));
    }

    private Section selectSection(HttpServletRequest request, Section section) {
	if (section != null) {
	    request.setAttribute("section", section);

	    final Set<Section> selectedSections = new HashSet<Section>();
	    for (Section currentSection = section; currentSection != null; currentSection = currentSection.getSuperiorSection()) {
		selectedSections.add(currentSection);
	    }

	    request.setAttribute("selectedSections", selectedSections);
	}

	return section;
    }

    protected Item selectItem(HttpServletRequest request) {
	Item item = getItem(request);

	if (item != null) {
	    selectSection(request, item.getSection());
	    request.setAttribute("item", item);
	}

	return item;
    }

    private Item getItem(HttpServletRequest request) {
	String parameter = request.getParameter("itemID");

	if (parameter == null) {
	    return null;
	}

	Integer itemID = Integer.valueOf(parameter);
	return (Item) rootDomainObject.readContentByOID(itemID);
    }

    protected Section getSection(final HttpServletRequest request) {
	String parameter = request.getParameter("sectionID");

	if (parameter == null) {
	    return null;
	}

	final Content content = rootDomainObject.readContentByOID(Integer.valueOf(parameter));
	return content instanceof Section ? (Section) content : null;
    }

    protected void setSectionBreadCrumbs(HttpServletRequest request) {
	Section section = selectSection(request);
	Item item = selectItem(request);

	List<Section> sections = new ArrayList<Section>();

	if (section != null && item == null) {
	    section = section.getSuperiorSection();
	}

	while (section != null) {
	    sections.add(0, section);

	    section = section.getSuperiorSection();
	}

	request.setAttribute("sectionCrumbs", sections);
    }

    protected abstract ActionForward getSiteDefaultView(ActionMapping mapping, ActionForm form, HttpServletRequest request,
	    HttpServletResponse response);

    protected String getDirectLinkContext(HttpServletRequest request) {
	return null;
    }

    protected ExecutionYearIntervalBean generateSearchBean() {
	return new ExecutionYearIntervalBean(ExecutionYear.readCurrentExecutionYear().getPreviousExecutionYear(3), ExecutionYear
		.readCurrentExecutionYear());
    }
}