/*******************************************************************************
 * Copyright (c) 2004 - 2006 University Of British Columbia and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     University Of British Columbia - initial API and implementation
 *******************************************************************************/

package org.eclipse.mylyn.internal.bugzilla.core;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.eclipse.mylyn.internal.tasks.core.RepositoryConfiguration;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

/**
 * Quick config rdf parser.
 * 
 * <pre>
 *  config.cgi?ctype=rdf
 * </pre>
 * 
 * Populates a <link>ProductConfiguration</link> data structure.
 * 
 * @author Rob Elves
 */
public class SaxConfigurationContentHandler extends DefaultHandler {

	private static final String ELEMENT_RESOLUTION = "resolution";

	private static final String ELEMENT_STATUS_OPEN = "status_open";

	private static final String ELEMENT_TARGET_MILESTONE = "target_milestone";

	private static final String ELEMENT_TARGET_MILESTONES = "target_milestones";

	private static final String ELEMENT_INSTALL_VERSION = "install_version";

	private static final String ATTRIBUTE_RDF_ABOUT = "rdf:about";

	private static final String ATTRIBUTE_RESOURCE = "resource";

	private static final String ELEMENT_VERSION = "version";

	private static final String ELEMENT_VERSIONS = "versions";

	private static final String ELEMENT_COMPONENT = "component";

	private static final String ELEMENT_COMPONENTS = "components";

	private static final String ELEMENT_NAME = "name";

	private static final String ELEMENT_PRODUCTS = "products";

	private static final String ELEMENT_SEVERITY = "severity";

	private static final String ELEMENT_PRIORITY = "priority";
	
	private static final String ELEMENT_KEYWORD = "keyword";

	private static final String ELEMENT_OP_SYS = "op_sys";

	private static final String ELEMENT_PLATFORM = "platform";

	private static final String ELEMENT_LI = "li";

	private static final String ELEMENT_STATUS = "status";

	private static final int EXPECTING_ROOT = 0;

	private static final int IN_INSTALL_VERSION = 1 << 1;

	private static final int IN_STATUS = 1 << 2;

	private static final int IN_PLATFORM = 1 << 3;

	private static final int IN_OP_SYS = 1 << 4;

	private static final int IN_PRIORITY = 1 << 5;

	private static final int IN_SEVERITY = 1 << 6;

	private static final int IN_PRODUCTS = 1 << 7;

	private static final int IN_COMPONENTS = 1 << 8;

	private static final int IN_VERSIONS = 1 << 9;

	private static final int IN_LI = 1 << 10;

	private static final int IN_LI_LI = 1 << 11;

	private static final int IN_NAME = 1 << 12;

	private static final int IN_COMPONENT = 1 << 13;

	private static final int IN_VERSION = 1 << 14;

	private static final int IN_TARGET_MILESTONES = 1 << 15;

	private static final int IN_TARGET_MILESTONE = 1 << 16;

	private static final int IN_STATUS_OPEN = 1 << 17;
	
	private static final int IN_RESOLUTION = 1 << 18;
	
	private static final int IN_KEYWORD = 1 << 19;

	private int state = EXPECTING_ROOT;

	private String currentProduct;

	private String about;

	private RepositoryConfiguration configuration = new RepositoryConfiguration(new BugzillaAttributeFactory());

	private Map<String, List<String>> components = new HashMap<String, List<String>>();

	private Map<String, List<String>> versions = new HashMap<String, List<String>>();

	private Map<String, List<String>> milestones = new HashMap<String, List<String>>();

	private Map<String, String> componentNames = new HashMap<String, String>();

	private Map<String, String> versionNames = new HashMap<String, String>();

	private Map<String, String> milestoneNames = new HashMap<String, String>();

	public RepositoryConfiguration getConfiguration() {
		return configuration;
	}

	@Override
	public void characters(char[] ch, int start, int length) throws SAXException {
		switch (state) {

		case IN_PRODUCTS | IN_LI | IN_NAME:
			configuration.addProduct(String.copyValueOf(ch, start, length));
			currentProduct = String.copyValueOf(ch, start, length);
			break;
		case IN_COMPONENTS | IN_LI | IN_COMPONENT | IN_NAME:
			if (about != null) {
				String name = String.copyValueOf(ch, start, length);
				componentNames.put(about, name);
			}
			break;
		case IN_VERSIONS | IN_LI | IN_VERSION | IN_NAME:
			if (about != null) {
				String name = String.copyValueOf(ch, start, length);
				versionNames.put(about, name);
			}
			break;
		case IN_TARGET_MILESTONES | IN_LI | IN_TARGET_MILESTONE | IN_NAME:
			if (about != null) {
				String name = String.copyValueOf(ch, start, length);
				milestoneNames.put(about, name);
			}
			break;
		case IN_PLATFORM | IN_LI:
			configuration.addPlatform(String.copyValueOf(ch, start, length));
			break;
		case IN_OP_SYS | IN_LI:
			configuration.addAttributeValue(BugzillaReportElement.OP_SYS.getKeyString(), String.copyValueOf(ch, start, length));
			configuration.addOS(String.copyValueOf(ch, start, length));
			break;
		case IN_PRIORITY | IN_LI:
			configuration.addPriority(String.copyValueOf(ch, start, length));
			break;
		case IN_SEVERITY | IN_LI:
			configuration.addSeverity(String.copyValueOf(ch, start, length));
			break;
		case IN_INSTALL_VERSION:
			configuration.setInstallVersion(String.copyValueOf(ch, start, length));
			break;
		case IN_STATUS | IN_LI:
			configuration.addStatus(String.copyValueOf(ch, start, length));
			break;
		case IN_RESOLUTION | IN_LI:
			configuration.addResolution(String.copyValueOf(ch, start, length));
			break;
		case IN_KEYWORD | IN_LI:
			configuration.addAttributeValue(BugzillaReportElement.KEYWORDS.getKeyString(), String.copyValueOf(ch, start, length));
			configuration.addKeyword(String.copyValueOf(ch, start, length));
			break;
		case IN_STATUS_OPEN | IN_LI:
			configuration.addOpenStatusValue(String.copyValueOf(ch, start, length));
			break;
		}
	}

	@Override
	public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {

		if (localName.equals(ELEMENT_STATUS)) {
			state = state | IN_STATUS;
		} else if (localName.equals(ELEMENT_LI) && ((state & IN_LI) == IN_LI)) {
			state = state | IN_LI_LI;
			parseResource(attributes);
		} else if (localName.equals(ELEMENT_LI) && ((state & IN_LI) != IN_LI)) {
			state = state | IN_LI;
		} else if (localName.equals(ELEMENT_PLATFORM)) {
			state = state | IN_PLATFORM;
		} else if (localName.equals(ELEMENT_OP_SYS)) {
			state = state | IN_OP_SYS;
		} else if (localName.equals(ELEMENT_PRIORITY)) {
			state = state | IN_PRIORITY;
		} else if (localName.equals(ELEMENT_SEVERITY)) {
			state = state | IN_SEVERITY;
		} else if (localName.equals(ELEMENT_PRODUCTS)) {
			state = state | IN_PRODUCTS;
		} else if (localName.equals(ELEMENT_OP_SYS)) {
			state = state | IN_OP_SYS;
		} else if (localName.equals(ELEMENT_NAME)) {
			state = state | IN_NAME;
		} else if (localName.equals(ELEMENT_COMPONENTS)) {
			state = state | IN_COMPONENTS;
		} else if (localName.equals(ELEMENT_COMPONENT)) {
			state = state | IN_COMPONENT;
			parseResource(attributes);
		} else if (localName.equals(ELEMENT_VERSIONS)) {
			state = state | IN_VERSIONS;
		} else if (localName.equals(ELEMENT_VERSION)) {
			state = state | IN_VERSION;
			parseResource(attributes);
		} else if (localName.equals(ELEMENT_INSTALL_VERSION)) {
			state = state | IN_INSTALL_VERSION;
		} else if (localName.equals(ELEMENT_TARGET_MILESTONES)) {
			state = state | IN_TARGET_MILESTONES;
		} else if (localName.equals(ELEMENT_TARGET_MILESTONE)) {
			state = state | IN_TARGET_MILESTONE;
			parseResource(attributes);
		} else if (localName.equals(ELEMENT_STATUS_OPEN)) {
			state = state | IN_STATUS_OPEN;
		} else if (localName.equals(ELEMENT_RESOLUTION)) {
			state = state | IN_RESOLUTION;
		} else if (localName.equals(ELEMENT_KEYWORD)) {
			state = state | IN_KEYWORD;
		}

	}

	private void parseResource(Attributes attributes) {

		switch (state) {
		case IN_PRODUCTS | IN_LI | IN_COMPONENTS | IN_LI_LI:
			if (attributes != null) {
				String compURI = attributes.getValue(ATTRIBUTE_RESOURCE);
				if (compURI != null) {

					List<String> compURIs = components.get(currentProduct);
					if (compURIs == null) {
						compURIs = new ArrayList<String>();
						components.put(currentProduct, compURIs);
					}
					compURIs.add(compURI);

				}
			}
			break;
		case IN_PRODUCTS | IN_LI | IN_VERSIONS | IN_LI_LI:
			if (attributes != null) {
				String resourceURI = attributes.getValue(ATTRIBUTE_RESOURCE);
				if (resourceURI != null) {
					List<String> versionUris = versions.get(currentProduct);
					if (versionUris == null) {
						versionUris = new ArrayList<String>();
						versions.put(currentProduct, versionUris);
					}
					versionUris.add(resourceURI);
				}
			}
			break;
		case IN_PRODUCTS | IN_LI | IN_TARGET_MILESTONES | IN_LI_LI:
			if (attributes != null) {
				String resourceURI = attributes.getValue(ATTRIBUTE_RESOURCE);
				if (resourceURI != null) {
					List<String> milestoneUris = milestones.get(currentProduct);
					if (milestoneUris == null) {
						milestoneUris = new ArrayList<String>();
						milestones.put(currentProduct, milestoneUris);
					}
					milestoneUris.add(resourceURI);
				}
			}
			break;
		case IN_COMPONENTS | IN_LI | IN_COMPONENT:
			if (attributes != null) {
				about = attributes.getValue(ATTRIBUTE_RDF_ABOUT);
			}
			break;
		case IN_VERSIONS | IN_LI | IN_VERSION:
			if (attributes != null) {
				about = attributes.getValue(ATTRIBUTE_RDF_ABOUT);
			}
			break;

		case IN_TARGET_MILESTONES | IN_LI | IN_TARGET_MILESTONE:
			if (attributes != null) {
				about = attributes.getValue(ATTRIBUTE_RDF_ABOUT);
			}
			break;

		}
	}

	@Override
	public void endElement(String uri, String localName, String qName) throws SAXException {

		// KEEP: && ((state & IN_LI) == IN_LI)

		if (localName.equals(ELEMENT_STATUS)) {
			state = state & ~IN_STATUS;
		} else if (localName.equals(ELEMENT_LI) && ((state & IN_LI_LI) == IN_LI_LI)) {
			state = state & ~IN_LI_LI;
		} else if (localName.equals(ELEMENT_LI) && ((state & IN_LI_LI) != IN_LI_LI)) {
			state = state & ~IN_LI;
		} else if (localName.equals(ELEMENT_PLATFORM)) {
			state = state & ~IN_PLATFORM;
		} else if (localName.equals(ELEMENT_OP_SYS)) {
			state = state & ~IN_OP_SYS;
		} else if (localName.equals(ELEMENT_PRIORITY)) {
			state = state & ~IN_PRIORITY;
		} else if (localName.equals(ELEMENT_SEVERITY)) {
			state = state & ~IN_SEVERITY;
		} else if (localName.equals(ELEMENT_PRODUCTS)) {
			state = state & ~IN_PRODUCTS;
		} else if (localName.equals(ELEMENT_OP_SYS)) {
			state = state & ~IN_OP_SYS;
		} else if (localName.equals(ELEMENT_NAME)) {
			state = state & ~IN_NAME;
		} else if (localName.equals(ELEMENT_COMPONENTS)) {
			state = state & ~IN_COMPONENTS;
		} else if (localName.equals(ELEMENT_COMPONENT)) {
			state = state & ~IN_COMPONENT;
		} else if (localName.equals(ELEMENT_VERSION)) {
			state = state & ~IN_VERSION;
		} else if (localName.equals(ELEMENT_VERSIONS)) {
			state = state & ~IN_VERSIONS;
		} else if (localName.equals(ELEMENT_INSTALL_VERSION)) {
			state = state & ~IN_INSTALL_VERSION;
		} else if (localName.equals(ELEMENT_TARGET_MILESTONE)) {
			state = state & ~IN_TARGET_MILESTONE;
		} else if (localName.equals(ELEMENT_TARGET_MILESTONES)) {
			state = state & ~IN_TARGET_MILESTONES;
		} else if (localName.equals(ELEMENT_STATUS_OPEN)) {
			state = state & ~IN_STATUS_OPEN;
		} else if (localName.equals(ELEMENT_RESOLUTION)) {
			state = state & ~IN_RESOLUTION;
		} else if (localName.equals(ELEMENT_KEYWORD)) {
			state = state & ~IN_KEYWORD;
		}

	}

	@Override
	public void endDocument() throws SAXException {
  
		for (String product : components.keySet()) {
			List<String> componentURIs = components.get(product);
			for (String uri : componentURIs) {
				String realName = componentNames.get(uri);
				if (realName != null) {
					configuration.addComponent(product, realName);
				}
			} 
		} 

		for (String product : versions.keySet()) {
			List<String> versionURIs = versions.get(product);
			for (String uri : versionURIs) {
				String realName = versionNames.get(uri);
				if (realName != null) {
					configuration.addVersion(product, realName);
				}
			}

		}

		for (String product : milestones.keySet()) {
			List<String> milestoneURIs = milestones.get(product);
			for (String uri : milestoneURIs) {
				String realName = milestoneNames.get(uri);
				if (realName != null) {
					configuration.addTargetMilestone(product, realName);
				}
			}

		}
		super.endDocument();
	}
}