/*
 *  Copyright 2010 Anyware Services
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package org.ametys.web.clientsideelement;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.ametys.core.ui.Callable;
import org.ametys.plugins.repository.AmetysObjectIterable;
import org.ametys.plugins.repository.AmetysRepositoryException;
import org.ametys.plugins.repository.UnknownAmetysObjectException;
import org.ametys.runtime.i18n.I18nizableText;
import org.ametys.web.repository.page.Page;
import org.ametys.web.repository.page.Page.LinkType;
import org.ametys.web.repository.page.Page.PageType;

/**
 * Page live UI item
 */
public class PreviewPageClientSideElement extends AbstractPageClientSideElement
{
    /**
     * Get the preview status of given pages
     * @param pageIds The page id
     * @return the result
     */
    @Callable
    public Map<String, Object> getStatus (List<String> pageIds)
    {
        Map<String, Object> results = new HashMap<>();
        
        results.put("invalid-pages", new ArrayList<Map<String, Object>>());
        results.put("allright-pages", new ArrayList<Map<String, Object>>());
        
        for (String pageId : pageIds)
        {
            Page page = _resolver.resolveById(pageId);

            Map<String, Object> pageParams = getPageDefaultParameters(page);
            
            if (_isPreviewable(page))
            {
                pageParams.put("description", getAllRightPageDescription(page));
                
                @SuppressWarnings("unchecked")
                List<Map<String, Object>> allrightPages = (List<Map<String, Object>>) results.get("allright-pages");
                allrightPages.add(pageParams);
            }
            else
            {
                pageParams.put("description", _getInvalidPageDescription(page));
                
                @SuppressWarnings("unchecked")
                List<Map<String, Object>> invalidPages = (List<Map<String, Object>>) results.get("invalid-pages");
                invalidPages.add(pageParams);
            }
        }
        
        return results;
    }
    
    /**
     * Get i18n description for invalid page
     * @param page The page
     * @return The {@link I18nizableText} description
     */
    private I18nizableText _getInvalidPageDescription (Page page)
    {
        List<String> i18nParameters = new ArrayList<>();
        i18nParameters.add(page.getTitle());
        
        I18nizableText ed = (I18nizableText) this._script.getParameters().get("invalid-page-description");
        return  new I18nizableText(ed.getCatalogue(), ed.getKey(), i18nParameters);
    }
    

    /**
     * Determine if this page is previewable
     * @param page The page to look at
     * @return true if the page can be previewed
     */
    private boolean _isPreviewable(Page page)
    {
        // Check for infinitive loop redirection
        ArrayList<String> pagesSequence = new ArrayList<>();
        pagesSequence.add(page.getId());
        if (_isInfiniteRedirection (page, pagesSequence))
        {
            getLogger().error("An infinite loop redirection was detected for page '" + page.getPathInSitemap() + "'");
            return false;
        }
        
        if (page.getType() == PageType.LINK && LinkType.PAGE.equals(page.getURLType()))
        {
            return _isPageExist(page.getURL()) && _isPreviewable((Page) _resolver.resolveById(page.getURL()));
        }
        
        if (page.getType() != PageType.NODE)
        {
            return true;
        }
        else
        {
            for (Page subPage : page.getChildrenPages())
            {
                if (_isPreviewable(subPage))
                {
                    return true;
                }
            }
        }
        return false;
    }
    
    private boolean _isPageExist (String id)
    {
        try
        {
            _resolver.resolveById(id);
            return true;
        }
        catch (UnknownAmetysObjectException e)
        {
            return false;
        }
    }
    
    private boolean _isInfiniteRedirection (Page page, List<String> pagesSequence)
    {
        Page redirectPage = _getPageRedirection (page);
        if (redirectPage == null)
        {
            return false;
        }
        
        if (pagesSequence.contains(redirectPage.getId()))
        {
            return true;
        }
        
        pagesSequence.add(redirectPage.getId());
        return _isInfiniteRedirection (redirectPage, pagesSequence);
    }
    
    private Page _getPageRedirection (Page page)
    {
        if (PageType.LINK.equals(page.getType()) && LinkType.PAGE.equals(page.getURLType()))
        {
            try
            {
                String pageId = page.getURL();
                return _resolver.resolveById(pageId);
            }
            catch (AmetysRepositoryException e)
            {
                return null;
            }
        }
        else if (PageType.NODE.equals(page.getType()))
        {
            AmetysObjectIterable<? extends Page> childPages = page.getChildrenPages();
            Iterator<? extends Page> it = childPages.iterator();
            if (it.hasNext())
            {
                return it.next();
            }
        }
        
        return null;
    }
}