/*
 *  Copyright 2017 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.extraction.component;

import java.util.Collections;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.cocoon.xml.AttributesImpl;
import org.apache.cocoon.xml.XMLUtils;
import org.xml.sax.ContentHandler;

import org.ametys.cms.repository.ModifiableDefaultContent;
import org.ametys.plugins.extraction.ExtractionConstants;
import org.ametys.plugins.extraction.execution.ExtractionExecutionContext;
import org.ametys.plugins.extraction.execution.ExtractionExecutionContextHierarchyElement;
import org.ametys.plugins.repository.AmetysObject;
import org.ametys.plugins.repository.AmetysObjectIterable;
import org.ametys.plugins.repository.TraversableAmetysObject;
import org.ametys.plugins.thesaurus.MicroThesaurus;
import org.ametys.plugins.thesaurus.Thesaurus;
import org.ametys.plugins.thesaurus.content.ThesaurusItemContentType;

/**
 * This class represents a thesaurus component of the extraction module
 */
public class ThesaurusExtractionComponent extends AbstractExtractionComponent
{
    private String _thesaurusName;
    private String _microThesaurusName;
    private int _maxLevel;
    
    private Thesaurus _thesaurus;
    private MicroThesaurus _microThesaurus;
    

    @Override
    public void configure(Configuration thesaurus) throws ConfigurationException
    {
        super.configure(thesaurus);
        _thesaurusName = thesaurus.getAttribute("thesaurusName");
        _microThesaurusName = thesaurus.getAttribute("microThesaurusName");
        _maxLevel = thesaurus.getAttributeAsInteger("max-level", -1);
    }

    @Override
    public void prepareComponentExecution(ExtractionExecutionContext context) throws Exception
    {
        super.prepareComponentExecution(context);
        _thesaurus = _thesaurusDAO.getThesaurusByName(_thesaurusName);
        if (null == _thesaurus)
        {
            throw new IllegalArgumentException(getLogsPrefix() + "thesaurus '" + _thesaurusName + "' does not exist");
        }
        
        _microThesaurus = _thesaurusDAO.getMicrothesaurusByName(_thesaurusName, _microThesaurusName);
        if (null == _microThesaurus)
        {
            throw new IllegalArgumentException(getLogsPrefix() + "microthesaurus '" + _microThesaurusName + "' does not exist in thesaurus '" + _thesaurusName + "'");
        }
    }
        
    @Override
    public void executeComponent(ContentHandler contentHandler, ExtractionExecutionContext context) throws Exception
    {
        AttributesImpl thesaurusAttributes = new AttributesImpl();
        thesaurusAttributes.addCDATAAttribute("thesaurusLabel", _thesaurus.getLabel());
        thesaurusAttributes.addCDATAAttribute("microThesaurusLabel", _microThesaurus.getLabel());
        XMLUtils.startElement(contentHandler, _tagName, thesaurusAttributes);
        
        AmetysObjectIterable<AmetysObject> children = _microThesaurus.getChildren();
        _processChildren(contentHandler, children, 1, context);
        
        XMLUtils.endElement(contentHandler, _tagName);
    }
    
    public Set<String> getContentTypes()
    {
        return new HashSet<>(Collections.singletonList(ThesaurusItemContentType.TERM_CONTENT_TYPE_ID));
    }

    private void _processChildren(ContentHandler contentHandler, AmetysObjectIterable<AmetysObject> children, int currentLevel, ExtractionExecutionContext context) throws Exception
    {
        int nbTermChildren = -1;
        int currentChildIndex = 0;
        if (getLogger().isDebugEnabled())
        {
            nbTermChildren = _getNbTermChildren(children);
        }
        
        for (AmetysObject child : children)
        {
            if (child instanceof ModifiableDefaultContent)
            {
                if (getLogger().isDebugEnabled())
                {
                    getLogger().debug(getLogsPrefix() + "executing term " + ++currentChildIndex + "/" + nbTermChildren + " at level " + currentLevel);
                }
                
                ModifiableDefaultContent term = (ModifiableDefaultContent) child;

                AttributesImpl attributes = new AttributesImpl();
                attributes.addCDATAAttribute("name", term.getTitle());
                XMLUtils.startElement(contentHandler, "term", attributes);

                if (_maxLevel < 0 || currentLevel < _maxLevel)
                {
                    ExtractionExecutionContextHierarchyElement currentContext = new ExtractionExecutionContextHierarchyElement(this, Collections.singleton(term), false);
                    executeSubComponents(contentHandler, context, currentContext);
                    _processChildren(contentHandler, term.getChildren(), currentLevel + 1, context);
                }
                else
                {
                    ExtractionExecutionContextHierarchyElement currentContext = new ExtractionExecutionContextHierarchyElement(this, Collections.singleton(term));
                    executeSubComponents(contentHandler, context, currentContext);
                }
                
                XMLUtils.endElement(contentHandler, "term");
            }
            else
            {
                _processChildren(contentHandler, ((TraversableAmetysObject) child).getChildren(), currentLevel, context);
            }
        }
    }
    
    private int _getNbTermChildren(AmetysObjectIterable<AmetysObject> children)
    {
        int nbTermChildren = 0;
        for (AmetysObject child : children)
        {
            if (child instanceof ModifiableDefaultContent)
            {
                nbTermChildren++;
            }
        }
        return nbTermChildren;
    }
    
    @Override
    public Map<String, Object> getComponentDetailsForTree()
    {
        Map<String, Object> details = super.getComponentDetailsForTree();
        details.put("tag", ExtractionConstants.THESAURUS_COMPONENT_TAG);
        
        @SuppressWarnings("unchecked")
        Map<String, Object> data = (Map<String, Object>) details.get("data");
        data.put("thesaurusName", this.getThesaurusName());
        data.put("microThesaurusName", this.getMicroThesaurusName());
        data.put("maxLevel", this.getMaxLevel());
        details.put("iconCls", "ametysicon-books");
        
        return details;
    }

    @Override
    protected String getDefaultTagName()
    {
        return "thesaurus";
    }

    @Override
    protected String getLogsPrefix()
    {
        return "Thesaurus component '" + _tagName + "': ";
    }

    /**
     * Retrieves the component thesaurus name
     * @return The thesaurus name
     */
    public String getThesaurusName()
    {
        return _thesaurusName;
    }

    /**
     * Set the thesaurus name
     * @param thesaurusName The thesaurus name to set
     */
    public void setThesaurusName(String thesaurusName)
    {
        _thesaurusName = thesaurusName;
    }

    /**
     * Retrieves the component microthesaurus name
     * @return The microthesaurus name
     */
    public String getMicroThesaurusName()
    {
        return _microThesaurusName;
    }

    /**
     * Set the microthesaurus name
     * @param thesaurusName The microthesaurus name to set
     */
    public void setMicroThesaurusName(String thesaurusName)
    {
        _microThesaurusName = thesaurusName;
    }

    /**
     * Retrieves the maximum level of specific terms to look at
     * @return The maximum level
     */
    public int getMaxLevel()
    {
        return _maxLevel;
    }

    /**
     * Set the maximum level of specific terms to look at
     * @param maxLevel The maximum level to set
     */
    public void setMaxLevel(int maxLevel)
    {
        _maxLevel = maxLevel;
    }
}