/*
 *  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.web.sitemap;

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.jcr.Node;
import javax.jcr.Property;
import javax.jcr.RepositoryException;
import javax.jcr.Value;

import org.apache.avalon.framework.component.Component;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.DefaultConfigurationBuilder;
import org.apache.avalon.framework.context.Context;
import org.apache.avalon.framework.context.ContextException;
import org.apache.avalon.framework.context.Contextualizable;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.avalon.framework.service.Serviceable;
import org.apache.cocoon.Constants;
import org.apache.cocoon.components.ContextHelper;
import org.apache.cocoon.environment.Request;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.ametys.core.right.RightManager;
import org.ametys.plugins.repository.AmetysObjectResolver;
import org.ametys.plugins.repository.UnknownAmetysObjectException;
import org.ametys.plugins.repository.data.holder.ModelLessDataHolder;
import org.ametys.plugins.repository.data.holder.group.Composite;
import org.ametys.plugins.repository.data.holder.group.Repeater;
import org.ametys.plugins.repository.jcr.JCRAmetysObject;
import org.ametys.plugins.repository.provider.RequestAttributeWorkspaceSelector;
import org.ametys.runtime.model.type.ElementType;
import org.ametys.web.repository.page.MetadataAwarePagesContainer;
import org.ametys.web.repository.page.Page;
import org.ametys.web.repository.page.Page.PageType;
import org.ametys.web.repository.page.PagesContainer;
import org.ametys.web.repository.site.Site;
import org.ametys.web.repository.sitemap.Sitemap;
import org.ametys.web.sitemap.SitemapIcon.Condition;

/**
 * Default implementation of {@link SitemapDecoratorsHandler}
 *
 */
public class DefaultSitemapDecoratorsHandler implements SitemapDecoratorsHandler, Serviceable, Contextualizable, Component
{
    private static Logger _logger = LoggerFactory.getLogger(DefaultSitemapDecoratorsHandler.class);
    
    /** The last time the file was loaded */
    protected Map<String, Long> _lastConfUpdate = new HashMap<>();
    
    private Map<String, List<SitemapIcon>> _icons = new HashMap<>();
    private Map<String, List<SitemapDecorator>> _decorators = new HashMap<>();
    
    private org.apache.cocoon.environment.Context _cocoonContext;
    private Context _context;

    private AmetysObjectResolver _resolver;

    private RightManager _rightManager; 
    
    @Override
    public void service(ServiceManager manager) throws ServiceException
    {
        _resolver = (AmetysObjectResolver) manager.lookup(AmetysObjectResolver.ROLE);
        _rightManager = (RightManager) manager.lookup(RightManager.ROLE);
    }
    
    @Override
    public List<SitemapIcon> getIcons(Site site)
    {
        String skinId = site.getSkinId();
        refreshValues(skinId);
        return _icons.get(skinId);
    }
    
    @Override
    public SitemapIcon getIcon(Page page)
    {
        String skinId = page.getSite().getSkinId();
        refreshValues(skinId);
        
        List<SitemapIcon> icons = _icons.get(skinId);
        for (SitemapIcon icon : icons)
        {
            if (_matches(icon, page))
            {
                return icon;
            }
        }
        
        return null;
    }
    
    @Override
    public List<SitemapDecorator> getDecorators (Site site)
    {
        String skinId = site.getSkinId();
        refreshValues(skinId);
        return _decorators.get(skinId);
    }
    
    @Override
    public List<SitemapDecorator> getDecorators(Sitemap sitemap)
    {
        String skinId = sitemap.getSite().getSkinId();
        refreshValues(skinId);
        
        List<SitemapDecorator> sitemapDecorators = new ArrayList<>();
        for (SitemapDecorator decorator : _decorators.get(skinId))
        {
            if (_matches(decorator, sitemap))
            {
                sitemapDecorators.add(decorator);
            }
        }
        return sitemapDecorators;
    }
    
    @Override
    public List<SitemapDecorator> getDecorators(Page page)
    {
        String skinId = page.getSite().getSkinId();
        refreshValues(skinId);
        
        List<SitemapDecorator> pageDecorators = new ArrayList<>();
        for (SitemapDecorator decorator : _decorators.get(skinId))
        {
            if (_matches(decorator, page))
            {
                pageDecorators.add(decorator);
            }
        }
        return pageDecorators;
    }
    
    /**
     * Determines if page matches the decorator
     * @param icon the icon
     * @param sitemap the sitemap
     * @return true if the page matches the decorator
     */
    protected boolean _matches (SitemapIcon icon, Sitemap sitemap)
    {
        if (!_matchesMetadata(icon, sitemap))
        {
            return false;
        }
        
        if (!_matchesProperties (icon, sitemap))
        {
            return false;
        }
        
        if (!icon.getTags().isEmpty())
        {
            return false;
        }
        
        if (icon.isLive())
        {
            return false;
        }
        
        if (icon.getPageType() != null)
        {
            return false;
        }
        
        if (icon.isRestricted() && _rightManager.hasAnonymousReadAccess(sitemap))
        {
            return false;
        }
        
        return true;
    }
    
    /**
     * Determines if page matches the decorator
     * @param icon the icon
     * @param page the page to test
     * @return true if the page matches the decorator
     */
    protected boolean _matches (SitemapIcon icon, Page page)
    {
        PageType pageType = icon.getPageType();
        if (pageType != null && !page.getType().equals(pageType))
        {
            return false;
        }
        
        if (!_matchesTags (icon, page))
        {
            return false;
        }
        
        if (!_matchesMetadata(icon, page))
        {
            return false;
        }
        
        if (!_matchesProperties (icon, page))
        {
            return false;
        }
        
        if (icon.isLive())
        {
            Request request = ContextHelper.getRequest(_context);
            String currentWp = RequestAttributeWorkspaceSelector.getForcedWorkspace(request);
            
            try
            {
                RequestAttributeWorkspaceSelector.setForcedWorkspace(request, "live");
                _resolver.resolveById(page.getId());
            }
            catch (UnknownAmetysObjectException e)
            {
                return false;
            }
            finally
            {
                RequestAttributeWorkspaceSelector.setForcedWorkspace(request, currentWp);
            }
        }
        
        if (icon.isRestricted() && _rightManager.hasAnonymousReadAccess(page))
        {
            return false;
        }
        
        return true;
    }
    
    private boolean _matchesTags (SitemapIcon icon, Page page)
    {
        List<String> tags = icon.getTags();
        
        if (!tags.isEmpty())
        {
            Condition condition = icon.getTagsCondition();
            if (condition == Condition.AND)
            {
                return page.getTags().containsAll(tags);
            }
            else if (condition == Condition.OR)
            {
                for (String tagName : tags)
                {
                    if (page.getTags().contains(tagName))
                    {
                        return true;
                    }
                }
                return false;
            }
        }
        return true;
    }
    
    private boolean _matchesMetadata (SitemapIcon icon, MetadataAwarePagesContainer page)
    {
        Map<String, String> metadata = icon.getMetadata();
        if (!metadata.isEmpty())
        {
            Condition condition = icon.getMetadataCondition();
            if (condition == Condition.AND)
            {
                return _matchesAndData (metadata, page);
            }
            else if (condition == Condition.OR)
            {
                return _matchesOrData (metadata, page);
            }
        }
        return true;
    }
    
    private boolean _matchesProperties (SitemapIcon icon, PagesContainer page)
    {
        Map<String, String> properties = icon.getProperties();
        if (!properties.isEmpty())
        {
            Condition condition = icon.getMetadataCondition();
            if (condition == Condition.AND)
            {
                return _matchesAndProperties(properties, page);
            }
            else if (condition == Condition.OR)
            {
                return _matchesOrProperties(properties, page);
            }
        }
        return true;
    }
    
    private boolean _matchesAndProperties (Map<String, String> properties, PagesContainer page)
    {
        if (!(page instanceof JCRAmetysObject))
        {
            return properties.size() == 0;
        }
        
        JCRAmetysObject jcrPage = (JCRAmetysObject) page;
        Node node = jcrPage.getNode();
        
        try
        {
            for (String propertyName : properties.keySet())
            {
                String valueToTest = properties.get(propertyName);
                
                if (!node.hasProperty(propertyName))
                {
                    // property does not exits
                    return false;
                }
                
                Property property = node.getProperty(propertyName);
                if (property.getDefinition().isMultiple())
                {
                    Value[] values = property.getValues();
                    if (valueToTest.length() > 0 && values.length == 0)
                    {
                        // metadata exits but is empty
                        return false;
                    }
                    else if (valueToTest.length() > 0)
                    {
                        String[] results = new String[values.length];
                        for (int i = 0; i < values.length; i++)
                        {
                            Value value = values[i];
                            results[i] = value.getString();
                        }
                        
                        List<String> asList = Arrays.asList(results);
                        String[] valuesToTest = valueToTest.split(",");
                        for (String val : valuesToTest)
                        {
                            if (!asList.contains(val))
                            {
                                // values do not contain all test values
                                return false;
                            }
                        }
                    }
                }
                else
                {
                    String value = property.getValue().getString();
                    if (valueToTest.length() > 0 && !valueToTest.equals(value))
                    {
                        // value is not equals to test value
                        return false;
                    }
                }
            }
        }
        catch (RepositoryException e)
        {
            _logger.error("An error occurred while testing properties", e);
            return false;
        }
        return true;
    }
    
    private boolean _matchesOrProperties (Map<String, String> properties, PagesContainer page)
    {
        if (!(page instanceof JCRAmetysObject))
        {
            return properties.size() == 0;
        }
        
        JCRAmetysObject jcrPage = (JCRAmetysObject) page;
        Node node = jcrPage.getNode();
        
        try
        {
            for (String propertyName : properties.keySet())
            {
                String valueToTest = properties.get(propertyName);
                
                if (node.hasProperty(propertyName))
                {
                    Property property = node.getProperty(propertyName);
                    if (property.getDefinition().isMultiple())
                    {
                        Value[] values = property.getValues();
                        if (valueToTest.length() == 0 && values.length > 0)
                        {
                            // multiple metadata exists and is not empty
                            return true; 
                        }
                        else if (valueToTest.length() != 0)
                        {
                            String[] results = new String[values.length];
                            for (int i = 0; i < values.length; i++)
                            {
                                Value value = values[i];
                                results[i] = value.getString();
                            }
                            
                            List<String> asList = Arrays.asList(results);
                            String[] valuesToTest = valueToTest.split(",");
                            boolean findAll = true;
                            for (String val : valuesToTest)
                            {
                                if (!asList.contains(val))
                                {
                                    findAll = false;
                                }
                            }
                            if (findAll)
                            {
                                // values contain all test values
                                return true;
                            }
                        }
                    }
                    else
                    {
                        String value = property.getString();
                        if (valueToTest.length() == 0 || valueToTest.equals(value))
                        {
                            // value is equals to test value
                            return true;
                        }
                    }
                }
            }
        }
        catch (RepositoryException e)
        {
            _logger.error("An error occurred while testing properties", e);
            return false;
        }
        
        return false;
    }
    
    @SuppressWarnings("unchecked")
    boolean _matchesAndData (Map<String, String> data, ModelLessDataHolder dataHolder)
    {
        for (String dataPath : data.keySet())
        {
            if (!dataHolder.hasValue(dataPath))
            {
                // data does not exits
                return false;
            }
            
            Object value = dataHolder.getValue(dataPath);
            
            if (value instanceof Composite)
            {
                if (((Composite) value).getDataNames().isEmpty())
                {
                    // the composite data is empty
                    return false;
                }
            }
            else if (value instanceof Repeater)
            {
                if (((Repeater) value).getSize() <= 0)
                {
                    // the repeater is empty
                    return false;
                }
            }
            else if (dataHolder.isMultiple(dataPath))
            {
                String valueToTest = data.get(dataPath);
                if (!valueToTest.isEmpty() && Array.getLength(value) == 0)
                {
                    // data exits but is empty
                    return false;
                }
                else if (!valueToTest.isEmpty())
                {
                    ElementType type = (ElementType) dataHolder.getType(dataPath);
                    if (!_findAllValuesInMultipleData(valueToTest, value, type))
                    {
                        // value does not contain all test values
                        return false;
                    }
                }
            }
            else
            {
                String valueToTest = data.get(dataPath);
                ElementType type = (ElementType) dataHolder.getType(dataPath);
                if (!valueToTest.isEmpty() && !valueToTest.equals(type.toString(value)))
                {
                    // value is not equals to test value
                    return false;
                }
            }
        }
        
        // All data have matched
        return true;
    }
    
    boolean _matchesOrData (Map<String, String> data, ModelLessDataHolder dataHolder)
    {
        for (String dataPath : data.keySet())
        {
            if (_matchesOrData(dataPath, data, dataHolder))
            {
                return true;
            }
        }
        
        return false;
    }
    
    @SuppressWarnings("unchecked")
    private boolean _matchesOrData (String dataPath, Map<String, String> data, ModelLessDataHolder dataHolder)
    {
        if (!dataHolder.hasValue(dataPath))
        {
            // data does not exists
            return false;
        }
        
        Object value = dataHolder.getValue(dataPath);
        
        if (value instanceof Composite)
        {
            if (!((Composite) value).getDataNames().isEmpty())
            {
                // composite data is not empty, the condition matched
                return true;
            }
        }
        else if (value instanceof Repeater)
        {
            if (((Repeater) value).getSize() > 0)
            {
                // repeater data is not empty, the condition matched
                return true;
            }
        }
        else if (dataHolder.isMultiple(dataPath))
        {
            String valueToTest = data.get(dataPath);
            if (valueToTest.isEmpty() && Array.getLength(value) > 0)
            {
                // multiple metadata exists and is not empty
                return true;
            }
            else if (!valueToTest.isEmpty())
            {
                ElementType type = (ElementType) dataHolder.getType(dataPath);
                if (_findAllValuesInMultipleData(valueToTest, value, type))
                {
                    // values contain all test values
                    return true;
                }
            }
        }
        else
        {
            String valueToTest = data.get(dataPath);
            ElementType type = (ElementType) dataHolder.getType(dataPath);
            if (valueToTest.isEmpty() || valueToTest.equals(type.toString(value)))
            {
                // value is equals to test value
                return true;
            }
        }
        
        return false;
    }
    
    private boolean _findAllValuesInMultipleData(String valueToTest, Object valueFromDataHolder, ElementType type)
    {
        List<String> valuesFromDataHolderAsString = new ArrayList<>();
        for (int i = 0; i < Array.getLength(valueFromDataHolder); i++)
        {
            @SuppressWarnings("unchecked")
            String valueAsString = type.toString(Array.get(valueFromDataHolder, i));
            valuesFromDataHolderAsString.add(valueAsString);
        }
        
        String[] valuesToTest = valueToTest.split(",");
        for (String value : valuesToTest)
        {
            if (!valuesFromDataHolderAsString.contains(value))
            {
                return false;
            }
        }
        
        return true;
    }
    
    @Override
    public void contextualize(Context context) throws ContextException
    {
        _cocoonContext = (org.apache.cocoon.environment.Context) context.get(Constants.CONTEXT_ENVIRONMENT_CONTEXT);
        _context = context;
    }
    
    /**
     * Refresh the configuration values
     * @param skinId the skin name
     */
    public void refreshValues(String skinId)
    {
        File configurationFile = null;

        try
        {
            configurationFile = new File (_cocoonContext.getRealPath("/skins/" + skinId + "/conf/sitemap-icons.xml"));
            if (!configurationFile.exists())
            {
                configurationFile = new File (_cocoonContext.getRealPath("/WEB-INF/param/sitemap-icons.xml"));
            }
            
            if (configurationFile.exists())
            {
                long lastConfUpdate = _lastConfUpdate.containsKey(skinId) ? _lastConfUpdate.get(skinId) : 0;
                if (lastConfUpdate == 0 || lastConfUpdate < configurationFile.lastModified())
                {
                    List<SitemapDecorator> decorators = new ArrayList<>();
                    List<SitemapIcon> icons = new ArrayList<>();
                    
                    try  (InputStream is = new FileInputStream(configurationFile))
                    {
                        Configuration configuration = new DefaultConfigurationBuilder().build(is);
                        
                        Configuration[] iconsConf = configuration.getChild("icons").getChildren("icon");
                        for (Configuration iconConf : iconsConf)
                        {
                            SitemapIcon icon = new SitemapIcon();
                            icon.configure(iconConf);
                            icons.add(icon);
                        }
                        
                        Configuration[] decoratorsConf = configuration.getChild("decorators").getChildren("decorator");
                        for (Configuration decoratorConf : decoratorsConf)
                        {
                            SitemapDecorator decorator = new SitemapDecorator();
                            decorator.configure(decoratorConf);
                            decorators.add(decorator);
                        }
                    }
                    
                    _lastConfUpdate.put(skinId, configurationFile.lastModified());
                    _icons.put(skinId, icons);
                    _decorators.put(skinId, decorators);
                }
            }
            else
            {
                _decorators.put(skinId, new ArrayList<SitemapDecorator>());
                _icons.put(skinId, new ArrayList<SitemapIcon>());
            }
        }
        catch (Exception e)
        {
            if (_logger.isWarnEnabled())
            {
                _logger.warn("Cannot read the configuration file params/sitemap-icons.xml. Continue as if file was not existing", e);
                _decorators.put(skinId, new ArrayList<SitemapDecorator>());
                _icons.put(skinId, new ArrayList<SitemapIcon>());
            }
        }
    }

}