/* *************************************************************************
 
 IT Mill Toolkit 

 Development of Browser User Interfaces Made Easy

 Copyright (C) 2000-2006 IT Mill Ltd
 
 *************************************************************************

 This product is distributed under commercial license that can be found
 from the product package on license.pdf. Use of this product might 
 require purchasing a commercial license from IT Mill Ltd. For guidelines 
 on usage, see licensing-guidelines.html

 *************************************************************************
 
 For more information, contact:
 
 IT Mill Ltd                           phone: +358 2 4802 7180
 Ruukinkatu 2-4                        fax:   +358 2 4802 7181
 20540, Turku                          email:  info@itmill.com
 Finland                               company www: www.itmill.com
 
 Primary source for information and releases: www.itmill.com

 ********************************************************************** */

package com.itmill.toolkit.terminal.web;

import com.itmill.toolkit.Application;
import com.itmill.toolkit.terminal.ThemeResource;
import com.itmill.toolkit.ui.FrameWindow;
import com.itmill.toolkit.ui.Window;

import java.text.DateFormatSymbols;
import java.util.Calendar;
import java.util.Collection;
import java.util.GregorianCalendar;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.Map;
import java.util.Vector;

import javax.servlet.http.HttpSession;

/**
 * This a function library that can be used from the theme XSL-files. It
 * provides easy access to current application, window, theme, webbrowser and
 * session. The internal threadlocal state must be maintained by the webadapter
 * in order to guarantee that it works.
 * 
 * @author IT Mill Ltd.
 * @version
 * @VERSION@
 * @since 3.0
 */

public class ThemeFunctionLibrary {

	static private final int APPLICATION = 0;

	static private final int WINDOW = 1;

	static private final int WEBBROWSER = 2;

	static private final int SESSION = 3;

	static private final int WEBADAPTERSERVLET = 4;

	static private final int THEME = 5;

	static private ThreadLocal state = new ThreadLocal();

	/**
	 * 
	 * @param application
	 * @param window
	 * @param webBrowser
	 * @param session
	 * @param webAdapterServlet
	 * @param theme
	 */
	static protected void setState(Application application, Window window,
			WebBrowser webBrowser, HttpSession session,
			ApplicationServlet webAdapterServlet, String theme) {
		state.set(new Object[] { application, window, webBrowser, session,
				webAdapterServlet, theme });
	}

	static protected void cleanState() {
		state.set(null);
	}

	/**
	 * Returns a reference to the application object associated with the session
	 * that the call came from.
	 */
	static public Application application() {
		try {
			return (Application) ((Object[]) state.get())[APPLICATION];
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Returns a reference to the current window object associated with the
	 * session that the call came from.
	 */
	static public Window window() {
		try {
			return (Window) ((Object[]) state.get())[WINDOW];
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Returns a reference to the browser object associated with the session
	 * that the call came from.
	 */
	static public WebBrowser browser() {
		try {
			return (WebBrowser) ((Object[]) state.get())[WEBBROWSER];
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Returns a reference to the current servlet http session object that is
	 * associated with the session that the call came from.
	 */
	static public HttpSession session() {
		try {
			return (HttpSession) ((Object[]) state.get())[SESSION];
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Returns a reference to the current theme name that is associated with the
	 * session that the call came from.
	 */
	static public String theme() {
		try {
			return (String) ((Object[]) state.get())[THEME];
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Returns an URI to the named resource from the named theme.
	 * 
	 * @param resource
	 * @param theme
	 */
	static public String resource(String resource, String theme) {
		try {
			return ((ApplicationServlet) ((Object[]) state.get())[WEBADAPTERSERVLET])
					.getResourceLocation(theme, new ThemeResource(resource));
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Returns an URI to the named resource.
	 * 
	 * @param resource
	 */
	static public String resource(String resource) {
		try {
			return ((ApplicationServlet) ((Object[]) state.get())[WEBADAPTERSERVLET])
					.getResourceLocation(theme(), new ThemeResource(resource));
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Generates the JavaScript for page that performs client-side combility
	 * checks.
	 */
	static public boolean probeClient() {
		return (browser().performClientCheck() && !browser()
				.isClientSideChecked());
	}

	/**
	 * Generates the JavaScript for page header that handles window refreshing,
	 * opening and closing.
	 * 
	 * Generates script that:
	 * <ul>
	 * <li>Requests that all windows that need repaint be reloaded</li>
	 * <li>Sets the window name</li>
	 * <li>Closes window if it is set to be closed </li>
	 * <ul>
	 * 
	 * @return
	 */
	static public String windowScript() {
		return generateWindowScript(
				window(),
				application(),
				(ApplicationServlet) ((Object[]) state.get())[WEBADAPTERSERVLET],
				browser());
	}

	/**
	 * 
	 * @param window
	 * @param app
	 * @param wa
	 * @param browser
	 * @return
	 */
	static protected String generateWindowScript(Window window,
			Application app, ApplicationServlet wa, WebBrowser browser) {

		StringBuffer script = new StringBuffer();
		LinkedList update = new LinkedList();

		// Adds all the windows needto update list
		Map dirtyWindows = wa != null ? wa.getDirtyWindows(app) : null;
		if (dirtyWindows != null)
			for (Iterator i = dirtyWindows.keySet().iterator(); i.hasNext();) {
				Window w = (Window) i.next();
				if (w != window) {
					if (w instanceof FrameWindow)
						update.addFirst(w);
					else
						update.addLast(w);
				}
			}

		// Removes all windows that are in frames, of such frame windows that
		// will be updated anyway
		Object[] u = update.toArray();
		if (u.length > 0 && (window != null && window instanceof FrameWindow))
			u[u.length - 1] = window;
		for (int i = 0; i < u.length; i++) {
			try {
				FrameWindow w = (FrameWindow) u[i];
				LinkedList framesets = new LinkedList();
				framesets.add(w.getFrameset());
				while (!framesets.isEmpty()) {
					FrameWindow.Frameset fs = (FrameWindow.Frameset) framesets
							.removeFirst();
					for (Iterator j = fs.getFrames().iterator(); j.hasNext();) {
						FrameWindow.Frame f = (FrameWindow.Frame) j.next();
						if (f instanceof FrameWindow.Frameset)
							framesets.add(f);
						else if (f.getWindow() != null) {
							update.remove(f.getWindow());
							wa.removeDirtyWindow(app, f.getWindow());
						}
					}
				}
			} catch (ClassCastException ignored) {
			}
		}

		// Sets window name
		if (window != null) {
			script.append("window.name = \"" + getWindowTargetName(app, window)
					+ "\";\n");
		}

		// Generates window updatescript
		for (Iterator i = update.iterator(); i.hasNext();) {
			Window w = (Window) i.next();
			script.append(getWindowRefreshScript(app, w, browser));

			wa.removeDirtyWindow(app, w);

			// Windows that are closed immediately are "painted" now
			if (w.getApplication() == null || !w.isVisible())
				w.requestRepaintRequests();
		}

		// Closes current window if it is not visible
		if (window == null || !window.isVisible())
			script.append("window.close();\n");

		return script.toString();
	}

	/**
	 * Returns an unique target name for a given window name.
	 * 
	 * @param application
	 * @param window
	 *            the Name of the window.
	 * @return An unique ID for window target.
	 */
	static public String getWindowTargetName(Application application,
			Window window) {
		try {
			return "" + application.hashCode() + "_" + window.getName();
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Returns an unique target name for current window.
	 * 
	 * @return An unique ID for window target.
	 */
	static public String getWindowTargetName() {
		return getWindowTargetName(application(), window());
	}

	/**
	 * Returns an unique target name for current window.
	 * 
	 * @param name
	 *            the name of the window.
	 * @return An unique ID for window target.
	 */
	static public String getWindowTargetName(String name) {
		Window w = application().getWindow(name);
		if (w != null)
			return getWindowTargetName(application(), w);
		else
			return name;
	}

	/* Static mapping for 0 to be sunday. */
	private static int[] weekdays = new int[] { Calendar.SUNDAY,
			Calendar.MONDAY, Calendar.TUESDAY, Calendar.WEDNESDAY,
			Calendar.THURSDAY, Calendar.FRIDAY, Calendar.SATURDAY };

	/**
	 * Returns the country and region code for current application locale.
	 * 
	 * @return the language Country code of the current application locale.
	 * @see Locale#getCountry()
	 */
	static public String getLocaleCountryId() {
		try {
			Application app = (Application) ((Object[]) state.get())[APPLICATION];
			return app.getLocale().getCountry();
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Returns the language code for current application locale.
	 * 
	 * @return the Language code for current application locale.
	 * @see Locale#getLanguage()
	 */
	static public String getLocaleLanguageId() {
		try {
			Application app = (Application) ((Object[]) state.get())[APPLICATION];
			return app.getLocale().getLanguage();
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Gets the name of first day of the week.
	 * 
	 * @return
	 */
	static public int getFirstDayOfWeek() {
		try {
			Application app = (Application) ((Object[]) state.get())[APPLICATION];
			Calendar cal = new GregorianCalendar(app.getLocale());
			int first = cal.getFirstDayOfWeek();
			for (int i = 0; i < 7; i++) {
				if (first == weekdays[i])
					return i;
			}
			return 0; // default to sunday
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Gets the name for week day.
	 * 
	 * @param dayOfWeek
	 *            the Number of week day. 0 sunday, 1 monday, ...
	 * @return the Name of week day in applications current locale.
	 */
	static public String getShortWeekday(int dayOfWeek) {
		try {
			Application app = (Application) ((Object[]) state.get())[APPLICATION];
			DateFormatSymbols df = new DateFormatSymbols(app.getLocale());
			return df.getShortWeekdays()[weekdays[dayOfWeek]];
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Gets the short name for month.
	 * 
	 * @param month
	 *            the Number of month. 0 is January, 1 is February, and so on.
	 * @return the Name of month in applications current locale.
	 */
	static public String getShortMonth(int month) {
		try {
			Application app = (Application) ((Object[]) state.get())[APPLICATION];
			DateFormatSymbols df = new DateFormatSymbols(app.getLocale());
			String monthName = df.getShortMonths()[month];
			return monthName;
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Gets the name for month.
	 * 
	 * @param month
	 *            the Number of month. 0 is January, 1 is February, and so on.
	 * @return the Name of month in applications current locale.
	 */
	static public String getMonth(int month) {
		try {
			Application app = (Application) ((Object[]) state.get())[APPLICATION];
			DateFormatSymbols df = new DateFormatSymbols(app.getLocale());
			String monthName = df.getMonths()[month];
			return monthName;
		} catch (NullPointerException e) {
			throw new IllegalStateException();
		}
	}

	/**
	 * Gets Form Action URL for the requested window.
	 * 
	 * <p>
	 * This returns the action for the window main form. This action can be set
	 * through WebApplicationContect setWindowFormAction method..
	 * </p>
	 * 
	 * @return the Form action for the current window.
	 */
	static public String getFormAction() {

		Window win = window();
		Application app = application();

		return ((WebApplicationContext) app.getContext())
				.getWindowFormAction(win);
	}

	/**
	 * Generates the links for CSS files to be included in html head.
	 * 
	 * @return
	 */
	static public String getCssLinksForHead() {
		ApplicationServlet as = (ApplicationServlet) ((Object[]) state.get())[WEBADAPTERSERVLET];
		Theme t = as.getThemeSource().getThemeByName(theme());

		// Also iterate parent themes
		Vector themes = new Vector();
		themes.add(t);
		while (t.getParent() != null) {
			String parentName = t.getParent();
			t = as.getThemeSource().getThemeByName(parentName);
			themes.add(t);
		}

		// Generates links
		StringBuffer links = new StringBuffer();
		for (int k = themes.size() - 1; k >= 0; k--) {
			Collection allFiles = ((Theme) themes.get(k)).getFileNames(
					browser(), Theme.MODE_HTML);
			for (Iterator i = allFiles.iterator(); i.hasNext();) {
				String file = (String) i.next();
				if (file.endsWith(".css")) {
					links
							.append("<LINK REL=\"STYLESHEET\" TYPE=\"text/css\" HREF=\""
									+ resource(file) + "\"/>\n");
				}
			}
		}

		return links.toString();
	}

	/**
	 * Generates the links for JavaScript files to be included in html head.
	 * 
	 * @return
	 */
	static public String getJavaScriptLinksForHead() {
		ApplicationServlet as = (ApplicationServlet) ((Object[]) state.get())[WEBADAPTERSERVLET];
		Theme t = as.getThemeSource().getThemeByName(theme());

		// Also iterate parent themes
		Vector themes = new Vector();
		themes.add(t);
		while (t.getParent() != null) {
			String parentName = t.getParent();
			t = as.getThemeSource().getThemeByName(parentName);
			themes.add(t);
		}

		// Generates links
		StringBuffer links = new StringBuffer();
		for (int k = themes.size() - 1; k >= 0; k--) {
			Collection allFiles = ((Theme) themes.get(k)).getFileNames(
					browser(), Theme.MODE_HTML);
			for (Iterator i = allFiles.iterator(); i.hasNext();) {
				String file = (String) i.next();
				if (file.endsWith(".js")) {
					links.append("<SCRIPT LANGUAGE=\"Javascript\" SRC=\""
							+ resource(file) + "\"></SCRIPT>\n");
				}
			}
		}

		return links.toString();
	}

	/**
	 * Generates the JavaScript for updating given window.
	 * 
	 * @param application
	 * @param window
	 * @param browser
	 * @return
	 */
	static protected String getWindowRefreshScript(Application application,
			Window window, WebBrowser browser) {

		if (application == null)
			return "";

		if (window == null)
			return "";

		if (window == null)
			return "";

		// If window is closed or hidden
		if (window.getApplication() == null || !window.isVisible())
			return "win = window.open(\"\",\""
					+ getWindowTargetName(application, window) + "\");\n  "
					+ "if (win != null) { win.close(); }\n";

		String url = window.getURL().toString();

		String features = "dependent=yes,";
		int width = window.getWidth();
		int height = window.getHeight();
		if (width >= 0)
			features += "width=" + width;
		if (height >= 0)
			features += ((features.length() > 0) ? "," : "") + "height="
					+ height;
		switch (window.getBorder()) {
		case Window.BORDER_NONE:
			features += ((features.length() > 0) ? "," : "")
					+ "toolbar=0,location=0,menubar=0,status=0,resizable=1,scrollbars="
					+ (window.isScrollable() ? "1" : "0");
			break;
		case Window.BORDER_MINIMAL:
			features += ((features.length() > 0) ? "," : "")
					+ "toolbar=1,location=0,menubar=0,status=1,resizable=1,scrollbars="
					+ (window.isScrollable() ? "1" : "0");
			break;
		case Window.BORDER_DEFAULT:
			features += ((features.length() > 0) ? "," : "")
					+ "toolbar=1,location=1,menubar=1,status=1,resizable=1,scrollbars="
					+ (window.isScrollable() ? "1" : "0");
			break;
		}

		String script = "win = window.open(\"\",\""
				+ getWindowTargetName(application, window) + "\",\"" + features
				+ "\");\n" + "if (win != null) {" + "var form = null;";

		if (browser != null
				&& (browser.getJavaScriptVersion().supports(
						WebBrowser.JAVASCRIPT_1_5) || browser
						.getJavaScriptVersion()
						.supports(WebBrowser.JSCRIPT_1_0))) {
			script += "try { form = win.document.forms[\"itmill\"]; if (typeof form == 'undefined') form = win.document.forms[\"millstone\"];"
					+ "} catch (e) { form = null;}";
		} else {
			script += "form = win.document.forms[\"itmill\"]; if (typeof form == 'undefined') form = win.document.forms[\"millstone\"];";
		}

		script += "if (form != null) {" + "form.submit();"
				+ "} else {win.location.href = \"" + url + "\";}}";

		return script;
	}
}