package org.eclipse.stem.utility.generators;

/*******************************************************************************
 * Copyright (c) 2006 IBM Corporation 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: IBM Corporation - initial API and implementation
 ******************************************************************************/

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

/**
 * STEM II Data Migration/Generation Utilities -- This is a utility class that
 * extracts the population data from the STEM I data files as a simple text file
 * that will be used in STEM II. The population data extracted is used during
 * generation of STEM II properties files.
 * 
 * Add the following values to the run configuration:
 * 
 * C:\stemII\org.eclipse.stem.utility\dataMigration\input\ISO3166-1\ISO3166_1_en.txt
 * C:\stemII\org.eclipse.stem.utility\dataMigration\input\migration\country_names.txt
 * C:\stemII\org.eclipse.stem.utility\dataMigration\input\AreaPopulationData\
 * 
 */

public class PopulationDataMigrator {

	/**
	 * Our source files for ISO 3166-1 codes and for the list of target
	 * countries.
	 */

	private String isoFile = null;

	private String targetFile = null;

	private String outputDir = null;

	String populationList = null;

	/**
	 * List for ISO 3166-1 codes and target countries.
	 */

	List targetList = null;

	List codeList = null;

	/**
	 * A map containing tuples of the form (location,area)
	 */
	Map populationMap = null;

	Map nameMap = null;

	/**
	 * Constructor
	 * 
	 * @param isoFile -
	 *            data file with the ISO3166-1 ALPHA_2 and ALPHA_3 codes.
	 * @param targetFile -
	 *            data file where we find a list of countries for generation of
	 *            their corresponding area.properties files.
	 * @param outputDir -
	 *            the output directory for the files generated.
	 */
	public PopulationDataMigrator(String isoFile, String targetFile,
			String outputDir) {
		this.isoFile = isoFile;
		this.targetFile = targetFile;
		this.outputDir = outputDir;
		populationMap = new HashMap();
		nameMap = new HashMap();
	}

	/**
	 * This method sets up and runs this generator.
	 * 
	 */
	public void run() {
		// Read and keep in memory a list of the countries we want.
		targetList = GenUtils.populateList(targetFile);

		// Read and keep in memory a list of the ISO3166-1 ALPHA2, ALPHA3, and
		// numeric codes.
		codeList = GenUtils.populateList(isoFile);

		// Now, process each item in the target list.
		process();

	}

	/**
	 * Method that loads the XML file containing the tests for this actor.
	 * 
	 * @param fileName
	 *            the XML test file
	 * 
	 * @throws FileNotFoundException
	 * @throws IOException
	 * 
	 * @return the root element of the XML document.
	 * 
	 */
	protected Element loadXML(String fileName) {

		Document doc = null;
		DocumentBuilder docBuilder = null;

		try {
			DocumentBuilderFactory factory = DocumentBuilderFactory
					.newInstance();
			// XML document builder
			docBuilder = factory.newDocumentBuilder();
			doc = docBuilder.newDocument();
			// Load XML file
			File xmlFile = new File(fileName);
			String filePath = xmlFile.getAbsolutePath();
			UtilLogger.logInformation("File path = " + filePath); //$NON-NLS-1$
			doc = docBuilder.parse(filePath);
		} catch (ParserConfigurationException pce) {
			System.out
					.println("LoadXML():  Error configuring xml document builder " //$NON-NLS-1$
							+ pce.getMessage());
		} catch (SAXException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

		// Return the root of this XML document
		return doc.getDocumentElement();
	}

	/**
	 * Read all arguments in a dataset, one by one.
	 * 
	 * @param file
	 *            a filename
	 * 
	 * @param level
	 *            adminstrative level
	 * 
	 * @throws FileNotFoundException
	 * @throws IOException
	 * 
	 * @return a map with tuples (Key=ID,Value=Populations)
	 * 
	 * 
	 */
	protected Map extractPopulationData(String file, int level) {

		Map<String, String> pMap = new HashMap<String, String>();

		Element root = loadXML(file);
		// get all the elements
		NodeList nl = root.getElementsByTagName("*"); //$NON-NLS-1$

		for (int i = 0; i < nl.getLength(); i++) {
			Element el = (Element) nl.item(i);
			String name = el.getAttribute("locationId").toUpperCase(); //$NON-NLS-1$
			String population = el.getAttribute("population"); //$NON-NLS-1$
			// String density = el.getAttribute("population_density");
			// //$NON-NLS-1$
			pMap.put(name, population);

		}

		return pMap;
	}

	// protected String extractPopulationData(String file, int level) {
	//
	// String populationList = null;
	//
	// Map<String, String> populationMap = new HashMap<String, String>();
	//
	// Element root = loadXML(file);
	// // get all the elements
	// NodeList nl = root.getElementsByTagName("*"); //$NON-NLS-1$
	//
	// for (int i = 0; i < nl.getLength(); i++) {
	// Element el = (Element) nl.item(i);
	// String name = el.getAttribute("locationId").toUpperCase(); //$NON-NLS-1$
	// String population = el.getAttribute("population"); //$NON-NLS-1$
	// String density = el.getAttribute("population_density"); //$NON-NLS-1$
	// // Store (concatenate)
	// if (populationList == null) {
	// populationList = name + ":" + String.valueOf(level) + ":" //$NON-NLS-1$
	// //$NON-NLS-2$
	// + population + ":" + density + "\n"; //$NON-NLS-1$ //$NON-NLS-2$
	// } else {
	// populationList += name + ":" + String.valueOf(level) + ":" //$NON-NLS-1$
	// //$NON-NLS-2$
	// + population + ":" + density + "\n"; //$NON-NLS-1$ //$NON-NLS-2$
	// }
	// }
	//
	// return populationList;
	// }

	/**
	 * Read all arguments in a dataset, one by one.
	 * 
	 * @param the
	 *            filename
	 * 
	 * @throws FileNotFoundException
	 * @throws IOException
	 * 
	 * @return a map with tuples (Key=ID,Value=Name)
	 * 
	 */
	protected Map extractNameData(String file) {

		Map<String, String> nameMap = new HashMap<String, String>();

		Element root = loadXML(file);
		// get all the elements
		NodeList nl = root.getElementsByTagName("*"); //$NON-NLS-1$

		for (int i = 0; i < nl.getLength(); i++) {
			Element regions = (Element) nl.item(i);
			NodeList locations = regions.getElementsByTagName("location"); //$NON-NLS-1$
			for (int j = 0; j < locations.getLength(); j++) {
				Element el = (Element) locations.item(j);
				String id = el.getAttribute("id").toUpperCase(); //$NON-NLS-1$
				String name = el.getAttribute("name").toUpperCase(); //$NON-NLS-1$

				// Store both values for later lookup. Use uppercase.
				nameMap.put(id, name);
			}
		}

		return nameMap;
	}

	/**
	 * Find all matches between locations and form a new tuple with the location
	 * name and area value for each location.
	 * 
	 * @param m1
	 *            A map containing tuples of the form (location,population)
	 * @param m2
	 *            A map containing tuples of the form (location,name)
	 * @param level
	 *            The administrative level
	 * 
	 * s@return A tuple of the form (name:area)
	 */
	protected String match(Map m1, Map m2, int level) {

		String result = null;
		Set keys = m1.keySet();
		Iterator it1 = keys.iterator();

		while (it1.hasNext()) {

			String key = (String) it1.next();

			if (m2.containsKey(key)) { // To be more strict, change this to
				// m2.equals(key)
				if (result == null) {

					if (((String) m2.get(key)).startsWith(":")) { //$NON-NLS-1$
						UtilLogger.logInformation("" //$NON-NLS-1$
								+ m2.get(key));
					}

					result = m2.get(key) + ":" + String.valueOf(level) + ":" //$NON-NLS-1$ //$NON-NLS-2$
							+ m1.get(key) + "\n"; //$NON-NLS-1$
				} else {
					result += m2.get(key) + ":" + String.valueOf(level) + ":" //$NON-NLS-1$ //$NON-NLS-2$
							+ m1.get(key) + "\n"; //$NON-NLS-1$
				}
			}
		}
		return result;
	}

	/**
	 * Process our global list of countries.
	 * 
	 */
	public void process() {

		PrintWriter outputFile = null;

		// Admin levels for each country
		// TO DO: fix these hardcoded variables. Should be set via parameters.
		final String populationPath = "C:\\EclipseProjects\\workspace2\\GreenScreen\\InstallTemplate\\Populations\\"; //$NON-NLS-1$
		final String namePath = "C:\\EclipseProjects\\workspace2\\GreenScreen\\InstallTemplate\\Maps\\"; //$NON-NLS-1$

		final int LEVELS = 1;

		for (int i = 0; i < targetList.size(); i++) {

			// Get the next country in the list.
			String country = ((String) targetList.get(i)).trim();

			// Get the ISO3166-1 info for this country
			ISOCode1 isoCode = GenUtils.getISOCode(country, codeList);

			if (isoCode == null) {
				UtilLogger.logInformation("iso code is null for " + country); //$NON-NLS-1$
				continue;
			}

			UtilLogger.logInformation("Country is :  " + country + " code = " //$NON-NLS-1$ //$NON-NLS-2$
					+ isoCode.getName());

			// Open output file
			if (outputFile == null) {
				String fileName = outputDir;
				fileName += isoCode.getName() + "_POPULATION.txt"; //$NON-NLS-1$
				outputFile = GenUtils.openWriter(fileName);
			}

			for (int j = 0; j <= LEVELS; j++) {

				// Open the population file
				String populationFile = populationPath;
				populationFile += isoCode.getAlpha3() + "_Human_" + j + ".xml"; //$NON-NLS-1$ //$NON-NLS-2$
				BufferedReader populationReader = GenUtils
						.openReader(populationFile);
				if (populationReader == null) {
					System.out
							.println("File not found for : " + populationFile); //$NON-NLS-1$
					continue;
				}

				// Open the names file
				String nameFile = namePath;
				nameFile += isoCode.getAlpha3() + "_Names_" + j + ".xml"; //$NON-NLS-1$ //$NON-NLS-2$
				BufferedReader nameReader = GenUtils.openReader(nameFile);
				if (nameReader == null) {
					UtilLogger.logInformation("File not found for : " + nameFile); //$NON-NLS-1$
					continue;
				}

				// Load the XML area and names documents and extract the data we
				// need
				try {
					// populationList = extractPopulationData(populationFile,
					// j);
					populationMap = extractPopulationData(populationFile, j);
					nameMap = extractNameData(nameFile);
					// now do the matchings
					String tuple = match(populationMap, nameMap, j);

					// write match to output file
					// outputFile.write(populationList.toString());
					outputFile.write(tuple);

					// Close the resources
					populationReader.close();
					nameReader.close();
					populationReader = null;
					nameReader = null;
					populationFile = null;
					nameFile = null;

					// Run garbage collection
					//System.gc();

				} catch (IOException e) {
					e.printStackTrace();
					continue;
				}
			} // for j

			if (outputFile != null) {
				outputFile.close();
				outputFile = null;
			}
		}
	}

	/**
	 * Main execution entry point.
	 * 
	 * @param args
	 */
	public static void main(String[] args) {
		final int ISO_FILE = 0;
		final int COUNTRY_FILE = 1;
		final int OUTPUT_DIR = 2;
		final int PARAMS = 3;

		if (args.length < PARAMS) {
			UtilLogger.logInformation("--Wrong arguments--"); //$NON-NLS-1$
			System.out
					.println("\tTo run, please provide the following arguments : "); //$NON-NLS-1$
			UtilLogger.logInformation("\t\t ISO 3166-1 file"); //$NON-NLS-1$						
			UtilLogger.logInformation("\t\t Target countries file"); //$NON-NLS-1$			
			UtilLogger.logInformation("\t\t Output directory"); //$NON-NLS-1$								
			return;
		}

		PopulationDataMigrator migrator = new PopulationDataMigrator(
				args[ISO_FILE], args[COUNTRY_FILE], args[OUTPUT_DIR]);
		migrator.run();
	}

}