package org.greenstone.gatherer.collection;
/**
 *#########################################################################
 *
 * A component of the Gatherer application, part of the Greenstone digital
 * library suite from the New Zealand Digital Library Project at the
 * University of Waikato, New Zealand.
 *
 * <BR><BR>
 *
 * Author: John Thompson, Greenstone Digital Library, University of Waikato
 *
 * <BR><BR>
 *
 * Copyright (C) 1999 New Zealand Digital Library Project
 *
 * <BR><BR>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * <BR><BR>
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * <BR><BR>
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *########################################################################
 */
import java.io.*;
import java.util.*;
import javax.swing.*;
import javax.swing.tree.*;
import org.greenstone.gatherer.Gatherer;
import org.greenstone.gatherer.cdm.CollectionDesignManager;
import org.greenstone.gatherer.collection.BuildOptions;
import org.greenstone.gatherer.collection.CollectionManager;
import org.greenstone.gatherer.file.FileNode;
import org.greenstone.gatherer.msm.ElementWrapper;
import org.greenstone.gatherer.msm.GDMManager;
import org.greenstone.gatherer.msm.MetadataSetManager;
import org.greenstone.gatherer.msm.MSMUtils;
import org.greenstone.gatherer.util.Utility;
import org.w3c.dom.*;
/** Collection provides a common collection point for all the information about a certain collection build session. It keeps a record of several other managers that actually handle the content of the collection, such as metadata sets and metadata itself.
 * @author John Thompson, Greenstone Digital Library, University of Waikato
 * @version 2.3c
 */
public class Collection {
    /** A reference to the BuildOptions. */
    public BuildOptions build_options;
    /** A reference to the Collection Design Manager. */
    public CollectionDesignManager cdm;
    /** A reference to the Greenstone Directory Metadata Manager. */
    public GDMManager gdm;
    /** A reference to the Metadata Set Manager. */
    public MetadataSetManager msm;
    /** <i>true</i> if the currently loaded collection has been saved since the last significant change, <i>false</i> otherwise. */
    private boolean saved = false;
    /** The collectio configuration file for this collection. */
    private CollectionConfiguration collect_cfg;
    /** The document around which this collection class is based. */
    private Document document;
    /** The file the collection is in (the file may not actually exist, such in the case of a legacy collection)! */
    private File file;
    /** The name of the argument element. */
    static final private String ARGUMENT = "Argument";
    /** The name of the build element. */
    static final private String BUILD = "Build";
    /** The name of the built attribute. */
    static final private String BUILT = "built";
    /** The name of the build config element. */
    static final private String BUILD_CONFIG = "BuildConfig";
    /** The name of the collection xml template. */
    static final private String COLLECTION_XML_TEMPLATE = "xml/template.col";
    /** The name of the directory mappings element. */
    static final private String DIRECTORY_MAPPINGS = "DirectoryMappings";
    /** The name of the file attribute. */
    static final private String FILE = "file";
    /** The name of the import element. */
    static final private String IMPORT = "Import";
    /** The name of the imported attribute. */
    static final private String IMPORTED = "imported";
    /** The name of the mapping element. */
    static final private String MAPPING = "Mapping";
    /** The name of the name attribute. */
    static final private String NAME = "name";
    /** The name of the true value. */
    static final private String TRUE = "true";
    /** Constructor. */
    public Collection(File collection_xml) {
	this.file = collection_xml;
	// Try to load this collections details.
	document = Utility.parse(collection_xml, false);
	// If that fails load the default settings for a collection.
	if(document == null) {
	    document = Utility.parse(COLLECTION_XML_TEMPLATE, true);
	}
	// Point the Configuration class at our gatherer config arguments.
	Gatherer.config.setCollectionConfiguration(document);
	// We also attempt to parse the collection configuration file.
	collect_cfg = new CollectionConfiguration(new File(collection_xml.getParentFile(), Utility.CONFIG_DIR));
	// Finally create all of the child managers that are directly dependant on a collection
	build_options = new BuildOptions(getBuildValues(), getImportValues());		  
    }
    /** Add a special directory mapping. */
    public boolean addDirectoryMapping(String name, File file) {
	boolean result = false;
	try {
	    Element document_element = document.getDocumentElement();
	    Element directory_mappings_element = (Element) MSMUtils.getNodeFromNamed(document_element, DIRECTORY_MAPPINGS);
				// Ensure the name isn't already in use.
	    boolean found = false;
	    NodeList mappings = directory_mappings_element.getElementsByTagName(MAPPING);
	    for(int i = 0; !found && i < mappings.getLength(); i++) {
		Element mapping_element = (Element) mappings.item(i);
		if(mapping_element.getAttribute(NAME).equalsIgnoreCase(name)) {
		    found = true;
		}
		mapping_element = null;
	    }
	    // Otherwise add the mapping.
	    if(!found) {
		Element mapping_element = document.createElement(MAPPING);
		mapping_element.setAttribute(NAME, name);
		mapping_element.setAttribute(FILE, file.toString());
		directory_mappings_element.appendChild(mapping_element);
		result = true;
		mapping_element = null;
	    }
	    mappings = null;
	    directory_mappings_element = null;
	    document_element = null;
	    saved = false;
	}
	catch (Exception error) {
	    Gatherer.printStackTrace(error);
	}
	return result;
    }

    /** Destructor. 
     * @see org.greenstone.gatherer.collection.CollectionModel */
    public void destroy() {
	cdm.destroy();
	gdm.destroy();
	msm.destroy();
	Gatherer.config.setCollectionConfiguration(null);
	cdm = null;
	document = null;
	gdm = null;
	msm = null;
    }
    /** Determine whether this collection has been successfully built in the past.
     * @return <i>true</i> if the collection has been built, <i>false</i> otherwise.
     */
    public boolean getBuilt() {
	return get(BUILT);
    }

    /** Determine the number of documents and folders in this collection. */
    public int getCount() {
	return getCount((TreeNode)Gatherer.c_man.getRecordSet().getRoot(), true, true);
    }

    /** Calculates the number of documents in this collection. */
    public int getDocumentCount() {
	return getCount((TreeNode)Gatherer.c_man.getRecordSet().getRoot(), false, true);
    }
    /** Retrieve the description of this collection.
     * @return The description as a <strong>String</strong>.
     */
    public String getDescription() {
	return collect_cfg.getDescription();
    }
    /** Retrieve a specific directory mapping associated with this collection.
     * @param name The name of the mapping to retrieve as a <strong>String</strong>.
     * @return The <strong>File</strong> this name maps to, or <i>null</i> if no such mapping.
     */
    public File getDirectoryMapping(String name) {
	File result = null;
	try {
	    Element document_element = document.getDocumentElement();
	    Element directory_mappings_element = (Element) MSMUtils.getNodeFromNamed(document_element, DIRECTORY_MAPPINGS);
				// Ensure the name isn't already in use.
	    boolean found = false;
	    NodeList mappings = directory_mappings_element.getElementsByTagName(MAPPING);
	    for(int i = 0; !found && i < mappings.getLength(); i++) {
		Element mapping_element = (Element) mappings.item(i);
		if(mapping_element.getAttribute(NAME).equalsIgnoreCase(name)) {
		    result = new File(MSMUtils.getValue(mapping_element));
		    found = true;
		}
		mapping_element = null;
	    }
	    mappings = null;
	    directory_mappings_element = null;
	    document_element = null;
	}
	catch(Exception error) {
	    Gatherer.printStackTrace(error);
	}
	return result;
    }
    /** Retrieve the special directory mappings associated with this collection.
     * @return A <strong>HashMap</strong> containing mappings from names to directories.
     */
    public HashMap getDirectoryMappings() {
	HashMap special_directories = new HashMap();
	try {
	    Element document_element = document.getDocumentElement();
	    Element directory_mappings_element = (Element) MSMUtils.getNodeFromNamed(document_element, DIRECTORY_MAPPINGS);
				// Ensure the name isn't already in use.
	    boolean found = false;
	    NodeList mappings = directory_mappings_element.getElementsByTagName(MAPPING);
	    for(int i = 0; !found && i < mappings.getLength(); i++) {
		Element mapping_element = (Element) mappings.item(i);
		String name = mapping_element.getAttribute(NAME);
		File file = new File(mapping_element.getAttribute(FILE));
		special_directories.put(name, file);
		file = null;
		name = null;
		mapping_element = null;
	    }
	    mappings = null;
	    directory_mappings_element = null;
	    document_element = null;
	}
	catch(Exception error) {
	    Gatherer.printStackTrace(error);
	}		  
	return special_directories;
    }
    /** Retrieve the authors email for this collection.
     * @return The email as a <strong>String</strong>.
     */
    public String getEmail() {
	return collect_cfg.getCreator();
    }
    /** Counts the number of folders used in the current record set. */
    public int getFolderCount() {
	return getCount((TreeNode)Gatherer.c_man.getRecordSet().getRoot(), true, false);
    }
    /** Determine if this collection has had an import action run upon it since the last major change.
     * @return <i>true</i> if an import has occured, <i>false</i> otherwise.
     */
    public boolean getImported() {
	return get(IMPORTED);
    }
    /** Retrieve the short name for this collection. 
     * @return The name as a <strong>String</strong>.
     */
    public String getName() {
	return file.getParentFile().getName();
    }
    /** Determine if this collection has been saved since the last major change.
     * @return <i>true</i> if it has been saved recently, <i>false</i> otherwise.
     */
    public boolean getSaved() {
	return saved;
    }
    /** Retrieve the title of this collection.
     * @return The title as a <strong>String</strong>.
     */
    public String getTitle() {
	return collect_cfg.getName();
    }
    /** Remove a previously defined special directory mapping.
     * @param name The name of the mapping to remove as a <strong>String</strong>.
     * @return The <strong>File</strong> of the mapping removed.
     */
    public File removeDirectoryMapping(String name) {
	File file = null;
	try {
	    Element document_element = document.getDocumentElement();
	    Element directory_mappings_element = (Element) MSMUtils.getNodeFromNamed(document_element, DIRECTORY_MAPPINGS);
				// Ensure the name isn't already in use.
	    boolean found = false;
	    NodeList mappings = directory_mappings_element.getElementsByTagName(MAPPING);
	    for(int i = 0; !found && i < mappings.getLength(); i++) {
		Element mapping_element = (Element) mappings.item(i);
		if(mapping_element.getAttribute(NAME).equalsIgnoreCase(name)) {
		    file = new File(MSMUtils.getValue(mapping_element));
		    directory_mappings_element.removeChild(mapping_element);
		    found = true;
		}
		mapping_element = null;
	    }
	    mappings = null;
	    directory_mappings_element = null;
	    document_element = null;
	    saved = false;
	}
	catch(Exception error) {
	    Gatherer.printStackTrace(error);
	}	
	return file;
    }
    /** Save this xml document to the given file. */
    public void save() {
	Utility.export(document, file);
    }
    /** Set the value of built to the given value.
     * @param value The new value for built, <i>true</i> if the collection has been built successfully, <i>false</i> otherwise.
     */
    public void setBuilt(boolean value) {
	set(BUILT, value);
	saved = false;
    }
    /** Set the value of imported to the given value.
     * @param value The new value for imported, <i>true</i> if the collection has been imported successfully, <i>false</i> otherwise.
     */
    public void setImported(boolean value) {
	set(IMPORTED, value);
	saved = false;
    }
    /** Set the value of saved to the given value.
     * @param value The new value for saved, <i>true</i> if the collection has been saved recently, <i>false</i> otherwise.
     */
    public void setSaved(boolean value) {
	saved = value;
    }
    /** Set the value of title to the given value.
     * @param title The new <strong>String</strong> title.
     */
    public void setTitle(String title) {
	collect_cfg.setName(title);
    }
    /** Method called to return a textual representation of a class, which in this case is the collections title.
     * @return A <strong>String</strong> containing the collections title.
     */
    public String toString() {
	return collect_cfg.getName();
    }
    /** Get the value of a collection argument. */
    private boolean get(String name) {
	boolean result = false;
	try {
	    Element document_element = document.getDocumentElement();
	    NodeList arguments = document_element.getElementsByTagName(ARGUMENT);
	    boolean found = false;
	    for(int i = 0; !found && i < arguments.getLength(); i++) {
		Element argument_element = (Element) arguments.item(i);
		if(argument_element.getParentNode() == document_element) {
		    if(argument_element.getAttribute(NAME).equalsIgnoreCase(BUILT)) {
			String value = MSMUtils.getValue(argument_element);
			if(value.equalsIgnoreCase(TRUE)) {
			    result = true;
			}
			found = true;
			value = null;
		    }
		}
		argument_element = null;
	    }
	    arguments = null;
	    document_element = null;
	}
	catch (Exception error) {
	    Gatherer.printStackTrace(error);
	}
	return result;
    }

    /** Method to retrieve the current build options associated with this Collection. */
    private Element getBuildValues() {
	Element build_values_element = null;
	try {
	    Element document_element = document.getDocumentElement();
	    Element build_config_element = (Element) MSMUtils.getNodeFromNamed(document_element, BUILD_CONFIG);
	    build_values_element = (Element) MSMUtils.getNodeFromNamed(build_config_element, BUILD);
	    build_config_element = null;
	    document_element = null;
	}
	catch (Exception error) {
	    Gatherer.printStackTrace(error);
	}
	return build_values_element;
    }

    /** Count either documents or folders, depending on the state of the given boolean. */
    private int getCount(TreeNode node, boolean count_folders, boolean count_files) {
	int count = 0;
	File file = ((FileNode)node).getFile();
	if(file.isFile() && count_files) {
	    count++;
	}
	else if(file.isDirectory() && count_folders) {
	    count++;
	}
	for(int i = 0; i < node.getChildCount(); i++) {
	    count = count + getCount(node.getChildAt(i), count_folders, count_files);
	}
	return count;
    }

    /** Method to retrieve the current import options associated with this Collection. */
    public Element getImportValues() {
	Element import_values_element = null;
	try {
	    Element document_element = document.getDocumentElement();
	    Element build_config_element = (Element) MSMUtils.getNodeFromNamed(document_element, BUILD_CONFIG);
	    import_values_element = (Element) MSMUtils.getNodeFromNamed(build_config_element, IMPORT);
	    build_config_element = null;
	    document_element = null;
	}
	catch (Exception error) {
	    Gatherer.printStackTrace(error);
	}
	return import_values_element;
    }

    /** Set the value of a collection argument. */
    private void set(String name, boolean value) {
	try {
	    Element document_element = document.getDocumentElement();
	    NodeList arguments = document_element.getElementsByTagName(ARGUMENT);
	    boolean found = false;
	    for(int i = 0; !found && i < arguments.getLength(); i++) {
		Element argument_element = (Element) arguments.item(i);
		if(argument_element.getParentNode() == document_element) {
		    if(argument_element.getAttribute(NAME).equalsIgnoreCase(BUILT)) {
			// Strip any current value nodes.
			while(argument_element.hasChildNodes()) {
			    argument_element.removeChild(argument_element.getFirstChild());
			}
			// Append new value
			argument_element.appendChild(document.createTextNode(value ? "true" : "false"));
		    }
		}
		argument_element = null;
	    }
	    arguments = null;
	    document_element = null;
	}
	catch (Exception error) {
	    Gatherer.printStackTrace(error);
	}
    }
}