/**
 * @author Conlan Rios (conlan@gmail.com)
 * A midlet for retrieving stock quotes off the internet via Yahoo! finances.
 * Allows you to get quotes for a specific symbol, lookup a ticker, and save
 * commonly viewed symbols in a portfolio.
 */
import java.io.IOException;
import java.io.InputStream;
import java.util.Vector;

import javax.microedition.io.Connector;
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.Gauge;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.ImageItem;
import javax.microedition.lcdui.Item;
import javax.microedition.lcdui.ItemCommandListener;
import javax.microedition.lcdui.ItemStateListener;
import javax.microedition.lcdui.List;
import javax.microedition.lcdui.Screen;
import javax.microedition.lcdui.StringItem;
import javax.microedition.lcdui.TextField;
import javax.microedition.midlet.MIDlet;
import javax.microedition.rms.RecordEnumeration;
import javax.microedition.rms.RecordFilter;
import javax.microedition.rms.RecordStore;
import javax.microedition.rms.RecordStoreException;

public class StockMIDlet extends MIDlet implements ItemStateListener, 
	CommandListener, ItemCommandListener
{
	public StockMIDlet()
	{
		Image getQuotesImage = null;
		Image portfolioImage = null;
		Image symbolLookupImage = null;
		try
		{
			getQuotesImage = Image.createImage("/getQuotes.PNG");
			portfolioImage = Image.createImage("/myPortfolio.PNG");
			symbolLookupImage = Image.createImage("/symbolLookup.PNG");
		}
		catch (IOException ex)
		{
			ex.printStackTrace();
		}
		
		getQuotesImageItem = getImageItem(GET_QUOTES_TITLE, getQuotesImage);
		portfolioImageItem = getImageItem(MY_PORTFOLIO_TITLE, portfolioImage);
		symbolLookupImageItem = getImageItem(SYMBOL_LOOKUP_TITLE, symbolLookupImage);
		
		mainScreen = new Form(MIDLET_TITLE);
		
		mainScreen.append(getQuotesImageItem);
		mainScreen.append(symbolLookupImageItem);
		mainScreen.append(portfolioImageItem);
		
		mainScreen.setItemStateListener(this);
		mainScreen.setCommandListener(this);
		mainScreen.addCommand(cmdExit);
	}
	
	private ImageItem getImageItem(String text, Image image)
	{
		ImageItem item = new ImageItem(text, image, Item.LAYOUT_2, null);
		item.setDefaultCommand(cmdGo);
		item.setItemCommandListener(this);
		return item;
	}
	
	public void itemStateChanged(Item item)
	{
		if (item == getQuotesField)
			getQuotesField.setString(getQuotesField.getString().toUpperCase());
	}
	
	public void commandAction(Command c, Displayable d)
	{
		if (d == getQuotesScreen)
		{
			if ((c == cmdSearch) && (!getQuotesField.getString().trim().equals("")))
			{
				previousScreen = getQuotesScreen;
				new Thread(new GetQuoteRunner(getQuotesField.getString())).start();
				getQuotesField.setString(""); 
			}
			else if (c == cmdBack)
			{
				display.setCurrent(mainScreen);
				getQuotesField.setString("");
			}
		}
		else if (d == getQuotesResults)
		{
			if (c == cmdBack)
				display.setCurrent(previousScreen);
			else if (c == cmdSave)
			{
				String symbol = ((StringItem) getQuotesResults.get(0)).getText();
				saveToPortfolio(symbol);
				display.setCurrent(successfulSave, previousScreen);
			}
		}
		else if (d == symbolLookupScreen)
		{
			if ((c == cmdSearch) && (!symbolLookupField.getString().trim().equals("")))
			{
				previousScreen = symbolLookupScreen;
				new Thread(new SymbolLookupRunner(symbolLookupField.getString())).start();
				symbolLookupField.setString("");
			}
			if (c == cmdBack)
			{
				display.setCurrent(mainScreen);
				symbolLookupField.setString("");
			}
		}
		else if (d == symbolLookupResults)
		{
			if (c == cmdBack)
				display.setCurrent(symbolLookupScreen);
			else if (c == List.SELECT_COMMAND || c == cmdGo)
			{
				String element = results.elementAt(
						symbolLookupResults.getSelectedIndex()).toString();
				int index = element.indexOf(SymbolLookupRunner.SYMBOL_DELIMETER);
				String query = element.substring(0, index);
				previousScreen = symbolLookupResults;
				new Thread(new GetQuoteRunner(query)).start();
			}
		}
		else if (d == portfolioScreen)
		{
			if (c == cmdBack)
				display.setCurrent(mainScreen);
			else if (c == List.SELECT_COMMAND || c == cmdGo)
			{
				if (portfolioScreen.size() > 0)
				{
					String query = portfolioScreen.getString(
							portfolioScreen.getSelectedIndex());
					previousScreen = portfolioScreen;
					new Thread(new GetQuoteRunner(query)).start();
				}
			}
		}
		else if (d == waitingScreen)
		{
			setDisplayScreen(previousScreen, null, null);
		}
		else if (d == mainScreen)
		{
			if (c == cmdExit)
			{
				destroyApp(true);
				notifyDestroyed();
			}
		}
	}

	public void commandAction(Command c, Item i)
	{
		if (i == getQuotesImageItem)
		{
			if (getQuotesScreen == null)
				setupQuoteLookup();
			if (waitingScreen == null)
				setupMiscScreens();
			
			display.setCurrent(getQuotesScreen);
		}
		else if (i == symbolLookupImageItem)
		{
			if (symbolLookupScreen == null)
				setupSymbolLookup();
			if (waitingScreen == null)
				setupMiscScreens();
			
			display.setCurrent(symbolLookupScreen);
		}
		else if (i == portfolioImageItem)
		{
			if (portfolioScreen == null)
				setupPortfolioScreen();
			if (waitingScreen == null)
				setupMiscScreens();
			loadMyPortfolio();
			display.setCurrent(portfolioScreen);
		}
	}
	
	protected void destroyApp(boolean arg0) {}

	protected void pauseApp() {}

	
	protected void startApp()
	{
		if (display == null)
			display = Display.getDisplay(this);
		
		display.setCurrent(mainScreen);
	}
	
	private void setupPortfolioScreen()
	{
		portfolioScreen = new List(MY_PORTFOLIO_TITLE, List.IMPLICIT);
		portfolioScreen.addCommand(cmdGo);
		portfolioScreen.addCommand(cmdBack);
		portfolioScreen.setCommandListener(this);
	}
	
	private void loadMyPortfolio()
	{
		portfolioScreen.deleteAll();
		RecordStore rs = null;
		RecordEnumeration re = null;
		try
		{
			try
			{
				rs = RecordStore.openRecordStore(RECORDSTORE_NAME, true);
				re = rs.enumerateRecords(null, null, false);
				while (re.hasNextElement())
				{
					String symbol = new String(re.nextRecord());
					portfolioScreen.append(symbol, null);
				}
			}
			finally
			{
				if (re != null) re.destroy();
				if (rs != null) rs.closeRecordStore();
			}
		}
		catch (RecordStoreException ex) 
		{
			ex.printStackTrace();
		}
	}
	
	/**
	 * Initiates the components for getting quotes.
	 */
	private void setupQuoteLookup()
	{
		getQuotesField = new TextField(null, "", QUERY_MAXLENGTH, TextField.ANY);
		
		getQuotesScreen = new Form(null);
		getQuotesScreen.append(getQuotesField);
		getQuotesScreen.addCommand(cmdBack);
		getQuotesScreen.addCommand(cmdSearch);
		
		getQuotesScreen.setItemStateListener(this);
		getQuotesScreen.setCommandListener(this);
		getQuotesScreen.setTitle(GET_QUOTES_TITLE);
	}
	
	/**
	 * Initiates the components for misc use. (waiting, invalid erorrs, saving)
	 */
	private void setupMiscScreens()
	{
		waitingScreen = new Alert("Searching...");
		waitingScreen.setTimeout(Alert.FOREVER);
		waitingScreen.setIndicator(new Gauge(null, false, Gauge.INDEFINITE, 
				Gauge.CONTINUOUS_RUNNING));
		waitingScreen.addCommand(new Command("Cancel", Command.CANCEL, 1));
		waitingScreen.setCommandListener(this);
		
		invalidTickerScreen = new Alert("Invalid Symbol or Query", 
				"No results were found. Please try again.", null, AlertType.ERROR);
		
		successfulSave = new Alert("Saved to Portfolio",
				"Symbol saved to portfolio.", null, AlertType.CONFIRMATION);
	}

	private void setupSymbolLookup()
	{
		symbolLookupField = new TextField(null, "", SYMBOL_MAXLENGTH, TextField.ANY);
		
		symbolLookupScreen = new Form(SYMBOL_LOOKUP_TITLE);
		symbolLookupScreen.append(symbolLookupField);
		symbolLookupScreen.addCommand(cmdBack);
		symbolLookupScreen.addCommand(cmdSearch);
		
		symbolLookupScreen.setCommandListener(this);
		symbolLookupScreen.setTitle(SYMBOL_LOOKUP_TITLE);
	}
	
	/**
	 * Saves a commonly viewed symbol to the portfolio for easy access later.
	 */
	private void saveToPortfolio(String symbol)
	{
		RecordStore rs = null;
		RecordEnumeration re = null;
		try
		{
			try
			{
				rs = RecordStore.openRecordStore(RECORDSTORE_NAME, true);
				re = rs.enumerateRecords(new PortfolioFilter(symbol),
						null, false);
				// check if the symbol to be saved is already there
				if (re.hasNextElement())
					return;
				
				byte[] raw = symbol.getBytes();
				rs.addRecord(raw, 0, raw.length);
			}
			finally
			{
				if (re != null) re.destroy();
				if (rs != null) rs.closeRecordStore();
			}
		}
		catch (RecordStoreException ex)
		{
			ex.printStackTrace();
		}
	}
	
	/**
	 * Sets the current display. Synchronized so a user that decides to cancel
	 * a search doesn't have their display change when search is completed.
	 * @param setTo screen to set to
	 * @param conditionScreen null or screen that display has to have set as 
	 * current
	 */
	private synchronized void setDisplayScreen(Screen setTo, Screen conditionScreen,
			Alert optionalAlert)
	{
		if (conditionScreen != null)
		{
			if (display.getCurrent() != conditionScreen)
				return;
		}
		
		if (optionalAlert == null)
			display.setCurrent(setTo);
		else
			display.setCurrent(optionalAlert, setTo);
	}

	/**
	 * Used when searching for a specific symbol in the portfolio.
	 */
	private class PortfolioFilter implements RecordFilter
	{
		public PortfolioFilter(String toFilterFor)
		{
			toFilter = toFilterFor;
		}
		
		public boolean matches(byte[] raw)
		{
			String record = new String(raw);
			return record.equals(toFilter);
		}
		
		private String toFilter;
	}
	
	/**
	 * Runner class for retrieving quotes off the net via yahoo! finances
	 */
	private class GetQuoteRunner implements Runnable
	{
		public GetQuoteRunner(String aSymbol)
		{
			symbol = aSymbol;
			symbol = symbol.replace(' ', '+');
		}
		
		public void run()
		{
			display.setCurrent(waitingScreen);
			StringBuffer quote = new StringBuffer();
			InputStream is = null;
			try
			{
				try
				{
					int ch = 0;
					is = Connector.openDataInputStream(GETQUOTES_URL + 
							symbol + GETQUOTES_FORMAT);
					while ((ch = is.read()) != -1)
						quote.append((char) ch);
				}
				finally
				{
					if (is != null)
						is.close();
				}
			}
			catch (IOException ex)
			{
				ex.printStackTrace();
			}
			quoteInfo = new String(quote).trim();
			parseQuoteInfo();
		}
		
		/** 
		 * Parses the string returned by the 'get quotes' and puts it in the
		 * correct format. 
		 */ 
		private void parseQuoteInfo()
		{
			if (getQuotesResults == null)
			{
				getQuotesResults = new Form(null);
				getQuotesResults.addCommand(cmdBack);
				getQuotesResults.addCommand(cmdSave);
				getQuotesResults.setCommandListener(StockMIDlet.this);
				try
				{
					upImage = Image.createImage("/up.PNG");
					downImage = Image.createImage("/down.PNG");
				}
				catch (IOException ex)
				{
					ex.printStackTrace();
				}
			}

			String quoteNameString = getStringFromQuoteInfo(true);
			String lastTradeString = getStringFromQuoteInfo(false);
			String dateString = getStringFromQuoteInfo(true);
			
			// check for valid symbol
			if (dateString.equals("N/A"))
			{
				setDisplayScreen(previousScreen, waitingScreen, 
						invalidTickerScreen);
				return;
			}
			
			String tradeTimeString = getStringFromQuoteInfo(true);
			String changeString = getStringFromQuoteInfo(false);
		
			getQuotesResults.setTitle(quoteNameString + " Summary");
			getQuotesResults.deleteAll();		
			
			getQuotesResults.append(getStringItem("Name", quoteNameString, true));
			getQuotesResults.append(getStringItem("Date", dateString, true));
			getQuotesResults.append(getStringItem("Change", changeString, false));
			
			double changeDouble = Double.parseDouble(changeString);
			ImageItem imageItem = new ImageItem(null, null, 
					Item.LAYOUT_2 | Item.LAYOUT_NEWLINE_AFTER, null);
			getQuotesResults.append(imageItem);
			if (changeDouble > 0)
				imageItem.setImage(upImage);
			else
				imageItem.setImage(downImage);
			
			getQuotesResults.append(getStringItem("Last Trade", lastTradeString, true));
			getQuotesResults.append(getStringItem("Trade Time", tradeTimeString, true));
			
			setDisplayScreen(getQuotesResults, waitingScreen, null);
		}
		
		private String getStringFromQuoteInfo(boolean enclosedInParentheses)
		{
			commaIndex = nextCommaIndex + 1;
			nextCommaIndex = quoteInfo.indexOf(",", commaIndex);
			if (enclosedInParentheses)
				return quoteInfo.substring(commaIndex + 1, nextCommaIndex - 1);
			else
				return quoteInfo.substring(commaIndex, nextCommaIndex);
			
		}
		
		private StringItem getStringItem(String title, String text, boolean newLine)
		{
			StringItem si = new StringItem(title, text);
			if (newLine)
				si.setLayout(Item.LAYOUT_2 | Item.LAYOUT_NEWLINE_AFTER);
			else
				si.setLayout(Item.LAYOUT_2);
			return si;
		}
		
		private int commaIndex = 0;
		private int nextCommaIndex = -1;
		private String quoteInfo;
		private String symbol;
	}
	
	/**
	 * Runner class for looking up symbols off the net.
	 */
	
	private class SymbolLookupRunner implements Runnable
	{
		public SymbolLookupRunner(String aQuery)
		{
			query = aQuery;
			query = query.replace(' ', '+');
		}
		
		public void run()
		{
			display.setCurrent(waitingScreen);
			StringBuffer input = new StringBuffer();
			InputStream is = null;
			try
			{
				try
				{
					int ch = 0;
					is = Connector.openDataInputStream(SYMBOL_LOOKUP_URL +
							query);
					while ((ch = is.read()) != -1)
						input.append((char) ch);
				}
				finally
				{
					if (is != null)
						is.close();
				}
			}
			catch (IOException ex)
			{
				ex.printStackTrace();
			}
			parseSearchResults(input.toString());
		}
		
		private void parseSearchResults(String input)
		{
			StringBuffer symbol = new StringBuffer();
			if (results == null)
				results = new Vector();
			else
				results.removeAllElements();
			int curIndex = 0;
			int from = 0;
			while ((curIndex = input.indexOf(SYMBOL_LOOKUP_PATTERN, from)) != -1)
			{
				boolean inCarot = true;
				boolean stop = false;
				int i = curIndex + SYMBOL_LOOKUP_PATTERN.length();
				int phrases = 0;
				while (!stop)
				{
					i ++;
					char ch = input.charAt(i);
					if (inCarot)
					{
						if (ch == OUT_CAROT_CHAR)
							inCarot = false;
					}
					else
					{
						if (ch == IN_CAROT_CHAR)
							inCarot = true;
						else
						{
							symbol.append(ch);
							if (input.charAt(i + 1) == IN_CAROT_CHAR)
							{
								phrases ++;
								if (phrases == MAX_SYMBOL_PHRASES)
									stop = true;
								else
									symbol.append(SYMBOL_DELIMETER);
							}
						}
					}
				}
				results.addElement(symbol.toString());
				// clear the string buffer for next time
				symbol.delete(0, symbol.length());
				curIndex ++;
				from = curIndex;
			}
			resolveSearchResults();
		}
		
		private void resolveSearchResults()
		{
			if (results.size() > 0)
			{
				// remove the last element, which is 'view all symbols'
				results.removeElementAt(results.size() - 1);
				
				if (symbolLookupResults == null)
				{
					symbolLookupResults = new List("Search Results", List.IMPLICIT);
					symbolLookupResults.addCommand(cmdBack);
					symbolLookupResults.addCommand(cmdGo);
					symbolLookupResults.setCommandListener(StockMIDlet.this);
				}
				
				symbolLookupResults.deleteAll();
				
				int size = results.size();
				for (int i = 0; i < size; i++)
				{
					String result = results.elementAt(i).toString();
					int index = result.indexOf(SYMBOL_DELIMETER) + 
						SYMBOL_DELIMETER.length();
					String finalResult = result.substring(index, result.length());
					symbolLookupResults.append(finalResult, null);
				}
				
				setDisplayScreen(symbolLookupResults, waitingScreen, null);
			}
			else
			{
				setDisplayScreen(symbolLookupScreen, waitingScreen, 
						invalidTickerScreen);
			}
		}
		
		public static final String SYMBOL_DELIMETER = "|_|";
		
		private String query;
		
		private final int MAX_SYMBOL_PHRASES = 2;
		private final char IN_CAROT_CHAR = '<';
		private final char OUT_CAROT_CHAR = '>';
	}
	
	private Alert waitingScreen;
	private Alert successfulSave;
	private Alert invalidTickerScreen;
	
	private Display display;
	
	private Form mainScreen;
	private Form getQuotesScreen;
	private Form getQuotesResults;
	private Form symbolLookupScreen;
	
	private Image upImage;
	private Image downImage;
	private ImageItem getQuotesImageItem;
	private ImageItem symbolLookupImageItem;
	private ImageItem portfolioImageItem;
	
	private List symbolLookupResults;
	private List portfolioScreen;
	
	private TextField getQuotesField;
	private TextField symbolLookupField;

	private Screen previousScreen;
	
	private Vector results;
	
	private final Command cmdGo = new Command("Go", Command.SCREEN, 1);
	private final Command cmdBack = new Command("Back", Command.BACK, 1);
	private final Command cmdExit = new Command("Quit", Command.EXIT, 1);
	private final Command cmdSave = new Command("Save", Command.SCREEN, 1);
	private final Command cmdSearch = new Command("Lookup", Command.SCREEN, 1);
	
	private final int SYMBOL_MAXLENGTH = 24;
	private final int QUERY_MAXLENGTH = 12;
	
	private final String MIDLET_TITLE = "Stock MIDlet";
	private final String GET_QUOTES_TITLE = "Get Quotes";
	private final String SYMBOL_LOOKUP_TITLE = "Lookup Symbol";
	private final String MY_PORTFOLIO_TITLE = "My Portfolio";
	
	private final String RECORDSTORE_NAME = "Portfolio";
	private final String GETQUOTES_URL = "http://download.finance.yahoo.com/d/quotes.csv?s=";
	private final String GETQUOTES_FORMAT = "&f=sl1d1t1c1ohgv&e=.csv";
	private final String SYMBOL_LOOKUP_URL = "http://finance.yahoo.com/lookup?s=";
	private final String SYMBOL_LOOKUP_PATTERN = "a href=\"/q?s=";
}