package org.greenstone.gatherer.metadata;


import java.io.*;
import java.util.*;
import javax.swing.tree.*;


/** This class represents all the metadata values for one metadata element */
public class MetadataValueTreeModel
    extends DefaultTreeModel
{
    public MetadataValueTreeModel(MetadataElement metadata_element)
    {
	// The root node of the value tree is the MetadataElement it represents
	super(new MetadataValueTreeNode(metadata_element));
    }


    public MetadataValueTreeNode addMetadataValue(String metadata_value)
    {
	return addMetadataValueInternal((MetadataValueTreeNode) root, metadata_value);
    }


    private MetadataValueTreeNode addMetadataValueInternal(MetadataValueTreeNode parent_metadata_value_tree_node, String metadata_value_remaining)
    {
	// Split the metadata value into a hierarchy
	int split_point = metadata_value_remaining.indexOf(MetadataValueTreeNode.METADATA_VALUE_TREE_NODE_HIERARCHY_TOKEN);
	String metadata_value = ((split_point == -1) ? metadata_value_remaining : metadata_value_remaining.substring(0, split_point));
	metadata_value_remaining = ((split_point == -1) ? "" : metadata_value_remaining.substring(split_point + 1));

	// Add the value into the tree in the correct place (sorted)
	MetadataValueTreeNode metadata_value_tree_node = null;
	for (int i = 0; i < parent_metadata_value_tree_node.getChildCount(); i++) {
	    MetadataValueTreeNode child_metadata_value_tree_node = (MetadataValueTreeNode) parent_metadata_value_tree_node.getChildAt(i);
	    int c = metadata_value.compareTo(child_metadata_value_tree_node.getValue());

	    // Insert node before existing value
	    if (c < 0) {
		metadata_value_tree_node = new MetadataValueTreeNode(metadata_value);
		insertNodeInto(metadata_value_tree_node, parent_metadata_value_tree_node, i);
		break;
	    }

	    // Node already exists (don't add again)
	    if (c == 0) {
		metadata_value_tree_node = child_metadata_value_tree_node;
		break;
	    }
	}

	// If no node has been added yet, it must go at the end of the list
	if (metadata_value_tree_node == null) {
	    metadata_value_tree_node = new MetadataValueTreeNode(metadata_value);
	    insertNodeInto(metadata_value_tree_node, parent_metadata_value_tree_node, parent_metadata_value_tree_node.getChildCount());
	}

	// If there is some of the metadata value remaining, add that hierarchically
	if (!metadata_value_remaining.equals("")) {
	    metadata_value_tree_node = addMetadataValueInternal(metadata_value_tree_node, metadata_value_remaining);
	}

	return metadata_value_tree_node;
    }


    public MetadataValueTreeNode getMetadataValueTreeNode(String metadata_value)
    {
	return getMetadataValueTreeNodeInternal((MetadataValueTreeNode) root, metadata_value);
    }


    private MetadataValueTreeNode getMetadataValueTreeNodeInternal(MetadataValueTreeNode parent_metadata_value_tree_node, String metadata_value_remaining)
    {
	// Split the metadata value into a hierarchy
	int split_point = metadata_value_remaining.indexOf(MetadataValueTreeNode.METADATA_VALUE_TREE_NODE_HIERARCHY_TOKEN);
	String metadata_value = ((split_point == -1) ? metadata_value_remaining : metadata_value_remaining.substring(0, split_point));
	metadata_value_remaining = ((split_point == -1) ? "" : metadata_value_remaining.substring(split_point + 1));

	// Find the value in the tree in the correct place (sorted)
	MetadataValueTreeNode metadata_value_tree_node = null;
	for (int i = 0; i < parent_metadata_value_tree_node.getChildCount(); i++) {
	    MetadataValueTreeNode child_metadata_value_tree_node = (MetadataValueTreeNode) parent_metadata_value_tree_node.getChildAt(i);
	    int c = metadata_value.compareTo(child_metadata_value_tree_node.getValue());

	    // Node doesn't exist in the tree
	    if (c < 0) {
		return null;
	    }
	 
	    // Node exists
	    if (c == 0) {
		metadata_value_tree_node = child_metadata_value_tree_node;
		break;
	    }
	}

	// If no node has been found, it doesn't exist
	if (metadata_value_tree_node == null) {
	    return null;
	}

	// If there is some of the metadata value remaining, find that recursively
	if (!metadata_value_remaining.equals("")) {
	    metadata_value_tree_node = getMetadataValueTreeNodeInternal(metadata_value_tree_node, metadata_value_remaining);
	}

	return metadata_value_tree_node;
    }


    public void writeHierarchyFile(File hierarchy_file)
    {
	try {
	    // Write the value tree out to a hierarchy file, for the Hierarchy classifier
	    FileOutputStream file_output_stream = new FileOutputStream(hierarchy_file);
	    OutputStreamWriter output_stream_writer = new OutputStreamWriter(file_output_stream, "UTF-8");
	    BufferedWriter buffered_writer = new BufferedWriter(output_stream_writer);

	    writeHierarchyFileInternal((MetadataValueTreeNode) root, "", buffered_writer);

	    buffered_writer.flush();
	    buffered_writer.close();
	}
	catch (Exception ex) {
	    ex.printStackTrace();
	}
    }


    private void writeHierarchyFileInternal(MetadataValueTreeNode parent_metadata_value_tree_node, String index, BufferedWriter buffered_writer)
	throws Exception
    {
	// Perform a depth-first traversal of the value tree, writing the metadata values out to the hfile
	for (int i = 0; i < parent_metadata_value_tree_node.getChildCount(); i++) {
	    MetadataValueTreeNode child_metadata_value_tree_node = (MetadataValueTreeNode) parent_metadata_value_tree_node.getChildAt(i);
	    String metadata_value_full = child_metadata_value_tree_node.getFullValue();
	    String index_string = (index.equals("") ? "" + (i + 1) : index + "." + (i + 1));
	    String metadata_value = child_metadata_value_tree_node.getValue();
	    String hierarchy_string = "\"" + metadata_value_full + "\"\t" + index_string + "\t\"" + metadata_value + "\"\n";
	    buffered_writer.write(hierarchy_string, 0, hierarchy_string.length());

	    // Apply recursively
	    writeHierarchyFileInternal(child_metadata_value_tree_node, index_string, buffered_writer);
	}
    }
}