/*
 *  Copyright 2011 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.plugins.blog.repository;

import java.util.ArrayList;
import java.util.Collections;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;

import org.ametys.core.util.I18nUtils;
import org.ametys.plugins.blog.BlogCacheManager;
import org.ametys.plugins.explorer.resources.ResourceCollection;
import org.ametys.plugins.repository.AmetysObject;
import org.ametys.plugins.repository.AmetysObjectIterable;
import org.ametys.plugins.repository.AmetysObjectIterator;
import org.ametys.plugins.repository.AmetysObjectResolver;
import org.ametys.plugins.repository.AmetysRepositoryException;
import org.ametys.plugins.repository.CollectionIterable;
import org.ametys.plugins.repository.EmptyIterable;
import org.ametys.plugins.repository.UnknownAmetysObjectException;
import org.ametys.plugins.repository.metadata.CompositeMetadata;
import org.ametys.web.repository.page.Page;
import org.ametys.web.repository.page.PagesContainer;
import org.ametys.web.repository.page.UnknownZoneException;
import org.ametys.web.repository.page.Zone;
import org.ametys.web.repository.site.Site;
import org.ametys.web.repository.sitemap.Sitemap;
import org.ametys.web.site.SiteConfigurationExtensionPoint;
import org.ametys.web.skin.SkinsManager;

/**
 * Virtual page representing the Post list by year page.
 */
public class VirtualYearsPage implements Page
{
    
    /** The page name. */
    public static final String NAME = "years";
    
    private AmetysObjectResolver _resolver;
    private BlogCacheManager _cacheManager;
    private I18nUtils _i18nUtils;
    private String _i18nCatalogue;
    private SiteConfigurationExtensionPoint _siteConf;
    private PagesContainer _root;
    private String _title;
    private SkinsManager _skinsManager;
    
    /**
     * Constructor.
     * @param resolver the {@link AmetysObjectResolver}.
     * @param cacheManager the {@link BlogCacheManager}.
     * @param skinsManager the {@link SkinsManager}.
     * @param i18nCache the i18n utils
     * @param i18nCatalogue the i18n catalogue.
     * @param siteConf the site configuration
     * @param root the blog root page.
     * @param title the page's title.
     */
    public VirtualYearsPage(AmetysObjectResolver resolver, BlogCacheManager cacheManager, SkinsManager skinsManager,  I18nUtils i18nCache, String i18nCatalogue, SiteConfigurationExtensionPoint siteConf, String title, PagesContainer root)
    {
        _resolver = resolver;
        _cacheManager = cacheManager;
        _skinsManager = skinsManager;
        _i18nUtils = i18nCache;
        _i18nCatalogue = i18nCatalogue;
        _siteConf = siteConf;
        _root = root;
        _title = title;
    }
    
    @Override
    public int getDepth() throws AmetysRepositoryException
    {
        int depth = 0;
        if (_root instanceof Page)
        {
            depth = ((Page) _root).getDepth();
        }
        
        return depth + 1;
    }

    @Override
    public Set<String> getReferers() throws AmetysRepositoryException
    {
        return null;
    }

    @Override
    public ResourceCollection getRootAttachments() throws AmetysRepositoryException
    {
        return null;
    }

    @Override
    public String getTemplate() throws AmetysRepositoryException
    {
        return null;
    }

    @Override
    public String getTitle() throws AmetysRepositoryException
    {
        return _title;
    }
    
    @Override
    public String getLongTitle() throws AmetysRepositoryException
    {
        return _title;
    }

    @Override
    public PageType getType() throws AmetysRepositoryException
    {
        return PageType.NODE;
    }

    @Override
    public String getURL() throws AmetysRepositoryException
    {
        throw new UnsupportedOperationException("getURL not supported on virtual blog pages");
    }

    @Override
    public LinkType getURLType() throws AmetysRepositoryException
    {
        throw new UnsupportedOperationException("getURLType not supported on virtual blog pages");
    }

    @Override
    public Zone getZone(String name) throws UnknownZoneException, AmetysRepositoryException
    {
        throw new UnknownZoneException("There is no zone on the blog years page.");
    }

    @Override
    public AmetysObjectIterable< ? extends Zone> getZones() throws AmetysRepositoryException
    {
        return new EmptyIterable<>();
    }

    @Override
    public boolean hasZone(String name) throws AmetysRepositoryException
    {
        return false;
    }

    @Override
    public AmetysObjectIterable<? extends Page> getChildrenPages() throws AmetysRepositoryException
    {
        ArrayList<Page> children = new ArrayList<>();
        
        SortedSet<Integer> years = new TreeSet<>(Collections.reverseOrder());
        years.addAll(_cacheManager.getYears(getSiteName(), getSitemapName()));
        
        for (Integer year : years)
        {
            VirtualYearPage page = new VirtualYearPage(_resolver, _cacheManager, _skinsManager, _i18nUtils, _i18nCatalogue, _siteConf, year, Integer.toString(year), _root);
            
            children.add(page);
        }
        
        return new CollectionIterable<>(children);
    }

    @Override
    public AmetysObjectIterable< ? extends Page> getChildrenPages(boolean includeInvisiblePages) throws AmetysRepositoryException
    {
        return getChildrenPages();
    }
    
    @Override
    public Page getChildPageAt(int index) throws UnknownAmetysObjectException, AmetysRepositoryException
    {
        if (index < 0)
        {
            throw new AmetysRepositoryException("Child page index cannot be negative");
        }
        
        AmetysObjectIterable< ? extends Page> childPages = getChildrenPages();
        AmetysObjectIterator< ? extends Page> it = childPages.iterator();
        
        try
        {
            it.skip(index);
            return it.next();
        }
        catch (NoSuchElementException e)
        {
            throw new UnknownAmetysObjectException("There's no child page at index " + index + " for page " + this.getId());
        }
    }
    
    @Override
    public String getPathInSitemap() throws AmetysRepositoryException
    {
        StringBuilder path = new StringBuilder(_root.getPathInSitemap());
        if (path.length() > 0)
        {
            path.append('/');
        }
        path.append(NAME);
        
        return path.toString();
    }

    @Override
    public Site getSite() throws AmetysRepositoryException
    {
        return _root.getSite();
    }

    @Override
    public String getSiteName() throws AmetysRepositoryException
    {
        return _root.getSiteName();
    }

    @Override
    public Sitemap getSitemap() throws AmetysRepositoryException
    {
        return _root.getSitemap();
    }

    @Override
    public String getSitemapName() throws AmetysRepositoryException
    {
        return _root.getSitemapName();
    }

    @SuppressWarnings("unchecked")
    @Override
    public <A extends AmetysObject> A getChild(String path) throws AmetysRepositoryException, UnknownAmetysObjectException
    {
        if (path.isEmpty())
        {
            throw new AmetysRepositoryException("Path must be non empty");
        }
        
        int slashPos = path.indexOf('/');
        
        String childName = slashPos == -1 ? path : path.substring(0, slashPos);
        
        int year;
        try
        {
            year = Integer.parseInt(childName);
        }
        catch (NumberFormatException e)
        {
            throw new AmetysRepositoryException(childName + " is not a valid year.", e);
        }
        
        VirtualYearPage page = new VirtualYearPage(_resolver, _cacheManager, _skinsManager, _i18nUtils, _i18nCatalogue, _siteConf, year, childName, _root);
        
        if (slashPos == -1)
        {
            return (A) page;
        }
        else
        {
            return (A) page.getChild(path.substring(slashPos + 1));
        }
    }

    @SuppressWarnings("unchecked")
    @Override
    public AmetysObjectIterable<? extends AmetysObject> getChildren() throws AmetysRepositoryException
    {
        return getChildrenPages();
    }

    @Override
    public boolean hasChild(String name) throws AmetysRepositoryException
    {
        try
        {
            int year = Integer.parseInt(name);
            
            return _cacheManager.hasYear(getSiteName(), getSitemapName(), year);
        }
        catch (NumberFormatException e)
        {
            // Ignore.
        }
        
        return false;
    }
    
    @Override
    public String getId() throws AmetysRepositoryException
    {
        return "blog-category://" + NAME + "?rootId=" + _root.getId();
    }
    
    @Override
    public String getName() throws AmetysRepositoryException
    {
        return NAME;
    }
    
    @SuppressWarnings("unchecked")
    @Override
    public PagesContainer getParent() throws AmetysRepositoryException
    {
        return _root;
    }

    @Override
    public String getParentPath() throws AmetysRepositoryException
    {
        return _root.getPath();
    }

    @Override
    public String getPath() throws AmetysRepositoryException
    {
        StringBuilder buff = new StringBuilder(getParentPath());
        if (!getParentPath().isEmpty())
        {
            buff.append('/');
        }
        buff.append(NAME);
        
        return buff.toString();
    }

    @Override
    public CompositeMetadata getMetadataHolder()
    {
        return new StaticCompositeMetadata();
    }

    @Override
    public Set<String> getTags() throws AmetysRepositoryException
    {
        return Collections.emptySet();
    }
    
    @Override
    public boolean isVisible() throws AmetysRepositoryException
    {
        return true;
    }
}