package net.sourceforge.fenixedu.presentationTier.Action;

import java.util.ArrayList;
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.Filtro.exception.FenixFilterException;
import net.sourceforge.fenixedu.applicationTier.Servico.exceptions.FenixServiceException;
import net.sourceforge.fenixedu.dataTransferObject.SearchDSpaceBean;
import net.sourceforge.fenixedu.dataTransferObject.SearchDSpaceBean.SearchElement;
import net.sourceforge.fenixedu.domain.DomainObject;
import net.sourceforge.fenixedu.domain.File;
import net.sourceforge.fenixedu.presentationTier.Action.base.FenixDispatchAction;

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

import pt.ist.fenixWebFramework.renderers.components.state.IViewState;
import pt.ist.fenixWebFramework.renderers.utils.RenderUtils;
import pt.utl.ist.fenix.tools.file.FileDescriptor;
import pt.utl.ist.fenix.tools.file.FileManagerFactory;
import pt.utl.ist.fenix.tools.file.FileSearchResult;
import pt.utl.ist.fenix.tools.file.VirtualPath;
import pt.utl.ist.fenix.tools.file.FileSearchCriteria.SearchField;
import pt.utl.ist.fenix.tools.file.FilesetMetadataQuery.ConjunctionType;

public abstract class SearchDSpaceGeneralAction extends FenixDispatchAction {

    protected ActionForward prepareSearch(ActionMapping mapping, ActionForm form, HttpServletRequest request,
	    HttpServletResponse response, String forwardTo) throws FenixFilterException, FenixServiceException {

	SearchDSpaceBean bean = createNewBean();
	bean.addSearchElement();
	request.setAttribute("bean", bean);
	return mapping.findForward(forwardTo);
    }

    protected ActionForward addNewSearchCriteria(ActionMapping mapping, ActionForm form, HttpServletRequest request,
	    HttpServletResponse response, String forwardTo) throws FenixFilterException, FenixServiceException {

	SearchDSpaceBean bean = getBean(request);
	String addIndex = request.getParameter("addIndex");
	if (addIndex == null) {
	    bean.addSearchElement();
	} else {
	    bean.addSearchElement(Integer.valueOf(addIndex));
	}
	request.setAttribute("bean", bean);
	request.setAttribute("pageNumber", bean.getPage());
	request.setAttribute("numberOfPages", bean.getNumberOfPages());
	return mapping.findForward(forwardTo);
    }

    protected ActionForward removeSearchCriteria(ActionMapping mapping, ActionForm form, HttpServletRequest request,
	    HttpServletResponse response, String forwardTo) throws FenixFilterException, FenixServiceException {

	SearchDSpaceBean bean = getBean(request);
	String removeIndex = request.getParameter("removeIndex");
	bean.removeSearchElement(Integer.valueOf(removeIndex));

	request.setAttribute("bean", bean);
	request.setAttribute("pageNumber", bean.getPage());
	request.setAttribute("numberOfPages", bean.getNumberOfPages());
	return mapping.findForward(forwardTo);
    }

    protected SearchDSpaceBean getBean(HttpServletRequest request) {
	SearchDSpaceBean bean;
	IViewState viewState = RenderUtils.getViewState("search");
	if (viewState == null) {
	    bean = reconstructBeanFromRequest(request);
	} else {
	    bean = (SearchDSpaceBean) viewState.getMetaObject().getObject();
	    RenderUtils.invalidateViewState();
	}
	return bean;
    }

    protected ActionForward moveIndex(ActionMapping mapping, ActionForm form, HttpServletRequest request,
	    HttpServletResponse response, String forwardTo) throws FenixFilterException, FenixServiceException {

	SearchDSpaceBean bean = reconstructBeanFromRequest(request);

	FileSearchResult searchResults = getSearchResults(request, bean, getSearchPath(request));
	putResearchResultsInBean(bean, searchResults.getSearchResults());

	request.setAttribute("bean", bean);
	return mapping.findForward(forwardTo);

    }

    protected ActionForward searchContent(ActionMapping mapping, ActionForm form, HttpServletRequest request,
	    HttpServletResponse response, String forwardTo) throws FenixFilterException, FenixServiceException {
	IViewState viewState = RenderUtils.getViewState("search");
	if (viewState == null) {
	    return prepareSearch(mapping, form, request, response, forwardTo);
	}
	SearchDSpaceBean bean = (SearchDSpaceBean) viewState.getMetaObject().getObject();
	FileSearchResult searchResults = getSearchResults(request, bean, getSearchPath(request));
	putResearchResultsInBean(bean, searchResults.getSearchResults());

	request.setAttribute("bean", bean);
	return mapping.findForward(forwardTo);
    }

    protected FileSearchResult getSearchResults(HttpServletRequest request, SearchDSpaceBean bean, VirtualPath restrictTo) {
	String index = request.getParameter("pageNumber");
	Integer start = (index == null) ? 1 : Integer.valueOf(index);
	Integer searchOffset = (start - 1) * bean.getPageSize();
	FileSearchResult searchResults = FileManagerFactory.getFactoryInstance().getFileManager().searchFiles(
		bean.getSearchCriteria(searchOffset), restrictTo);
	request.setAttribute("pageNumber", start);
	bean.setPage(start);
	bean.setTotalItems(searchResults.getTotalElements());
	int numberOfPages = searchResults.getTotalElements() / searchResults.getPageSize();
	numberOfPages += (searchResults.getTotalElements() % searchResults.getPageSize() != 0) ? 1 : 0;
	request.setAttribute("numberOfPages", numberOfPages);
	bean.setNumberOfPages(numberOfPages);
	return searchResults;
    }

    protected FileSearchResult getSearchResults(HttpServletRequest request, SearchDSpaceBean bean) {
	return getSearchResults(request, bean, null);
    }

    protected VirtualPath getSearchPath(HttpServletRequest request) {
	return null;
    }

    protected SearchDSpaceBean createNewBean() {
	return new SearchDSpaceBean();
    }

    protected void putResearchResultsInBean(SearchDSpaceBean bean, List<FileDescriptor> searchResults) {
	Set<File> researchResults = new HashSet<File>();
	for (FileDescriptor descriptor : searchResults) {
	    File documentFile = File.readByExternalStorageIdentification(descriptor.getUniqueId());
	    researchResults.add(documentFile);
	}
	bean.setResults(new ArrayList<DomainObject>(researchResults));
    }

    protected SearchDSpaceBean reconstructBeanFromRequest(HttpServletRequest request) {
	SearchDSpaceBean bean = createNewBean();

	String values[] = request.getParameterValues("criteria");
	for (int i = 0; i < values.length; i++) {
	    String fields[] = values[i].split(":");
	    bean.addSearchElement(new SearchElement(SearchField.valueOf(fields[1]), ((fields.length == 2) ? "" : fields[2]),
		    ConjunctionType.valueOf(fields[0])));
	}

	return bean;
    }

}