vaadin-framework/src/com/itmill/toolkit/terminal/gwt/client/ApplicationConnection.java

package com.itmill.toolkit.terminal.gwt.client;

import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Vector;

import com.google.gwt.http.client.Request;
import com.google.gwt.http.client.RequestBuilder;
import com.google.gwt.http.client.RequestCallback;
import com.google.gwt.http.client.RequestException;
import com.google.gwt.http.client.Response;
import com.google.gwt.json.client.JSONArray;
import com.google.gwt.json.client.JSONObject;
import com.google.gwt.json.client.JSONParser;
import com.google.gwt.json.client.JSONString;
import com.google.gwt.json.client.JSONValue;
import com.google.gwt.user.client.ui.FocusListener;
import com.google.gwt.user.client.ui.FocusWidget;
import com.google.gwt.user.client.ui.HasFocus;
import com.google.gwt.user.client.ui.HasWidgets;
import com.google.gwt.user.client.ui.Widget;
import com.itmill.toolkit.terminal.gwt.client.ui.ContextMenu;
import com.itmill.toolkit.terminal.gwt.client.ui.IView;

/**
 * Entry point classes define <code>onModuleLoad()</code>.
 */
public class ApplicationConnection implements FocusListener {

	private String appUri;

	private HashMap resourcesMap = new HashMap();

	private static Console console;

	private Vector pendingVariables = new Vector();

	private HashMap idToPaintable = new HashMap();

	private HashMap paintableToId = new HashMap();

	private final WidgetSet widgetSet;

	private ContextMenu contextMenu = null;

	private IView view;

	public ApplicationConnection(WidgetSet widgetSet) {
		this.widgetSet = widgetSet;
		appUri = getAppUri();

		if (isDebugMode()) {
			console = new DebugConsole();
		} else {
			console = new NullConsole();
		}

		makeUidlRequest("repaintAll=1");
		
		// TODO remove hardcoded id name
		view = new IView("itmtk-ajax-window");

	}

	public static Console getConsole() {
		return console;
	}

	private native static boolean isDebugMode() /*-{
	 var uri = $wnd.location;
	 var re = /debug[^\/]*$/;
	 return re.test(uri);
	 }-*/;

	public native String getAppUri()/*-{
	 return $wnd.itmtk.appUri;
	 }-*/;

	private native String getPathInfo()/*-{
	 return $wnd.itmtk.pathInfo;
	 }-*/;

	private void makeUidlRequest(String requestData) {
		console.log("Making UIDL Request with params: " + requestData);
		RequestBuilder rb = new RequestBuilder(RequestBuilder.POST, appUri
				+ "/UIDL" + getPathInfo());
		rb.setHeader("Content-Type",
				"application/x-www-form-urlencoded; charset=utf-8");
		try {
			rb.sendRequest(requestData, new RequestCallback() {
				public void onError(Request request, Throwable exception) {
					// TODO Better reporting to user
					console.error("Got error");
				}

				public void onResponseReceived(Request request,
						Response response) {
					handleReceivedJSONMessage(response);
				}

			});

		} catch (RequestException e) {
			// TODO Better reporting to user
			console.error(e.getMessage());
		}
	}

	private void handleReceivedJSONMessage(Response response) {
		Date start = new Date();
		String jsonText = response.getText().substring(3) + "}";
		JSONValue json;
		try {
			json = JSONParser.parse(jsonText);
		} catch (com.google.gwt.json.client.JSONException e) {
			console.log(e.getMessage() + " - Original JSON-text:");
			console.log(jsonText);
			return;
		}
		// Handle redirect
		JSONObject redirect = (JSONObject) ((JSONObject) json).get("redirect");
		if (redirect != null) {
			JSONString url = (JSONString) redirect.get("url");
			if (url != null) {
				console.log("redirecting to " + url.stringValue());
				redirect(url.stringValue());
				return;
			}
		}

		// Store resources
		JSONObject resources = (JSONObject) ((JSONObject) json)
				.get("resources");
		for (Iterator i = resources.keySet().iterator(); i.hasNext();) {
			String key = (String) i.next();
			resourcesMap.put(key, ((JSONString) resources.get(key))
					.stringValue());
		}

		// Store locale data
		if (((JSONObject) json).containsKey("locales")) {
			JSONArray l = (JSONArray) ((JSONObject) json).get("locales");
			for (int i = 0; i < l.size(); i++)
				LocaleService.addLocale((JSONObject) l.get(i));
		}

		// Process changes
		JSONArray changes = (JSONArray) ((JSONObject) json).get("changes");
		for (int i = 0; i < changes.size(); i++) {
			try {
				UIDL change = new UIDL((JSONArray) changes.get(i));
				try {
					console.dirUIDL(change);
				} catch (Exception e) {
					console.log(e.getMessage());
					// TODO: dir doesn't work in any browser although it should
					// work (works in hosted mode)
					// it partially did at some part but now broken.
				}
				UIDL uidl = change.getChildUIDL(0);
				Paintable paintable = getPaintable(uidl.getId());
				if (paintable != null)
					paintable.updateFromUIDL(uidl, this);
				else {
					if (!uidl.getTag().equals("window"))
						throw new IllegalStateException("Received update for "
								+ uidl.getTag()
								+ ", but there is no such paintable ("
								+ uidl.getId() + ") registered yet.");
					view.updateFromUIDL(uidl, this);
				}
			} catch (Throwable e) {
				e.printStackTrace();
			}
		}

		if (((JSONObject) json).containsKey("meta")) {
			JSONObject meta = ((JSONObject) json).get("meta").isObject();
			if (meta.containsKey("focus")) {
				String focusPid = meta.get("focus").isString().stringValue();
				Paintable toBeFocused = this.getPaintable(focusPid);
				if (toBeFocused instanceof HasFocus) {
					HasFocus toBeFocusedWidget = (HasFocus) toBeFocused;
					toBeFocusedWidget.setFocus(true);
				}
			}
		}

		long prosessingTime = (new Date().getTime()) - start.getTime();
		console.log(" Processing time was " + String.valueOf(prosessingTime)
				+ "ms for " + jsonText.length() + " characters of JSON");
		console.log("Referenced paintables: " + idToPaintable.size());

	}

	// Redirect browser
	private static native void redirect(String url)/*-{
	 $wnd.location = url;
	 }-*/;

	public void registerPaintable(String id, Paintable paintable) {
		idToPaintable.put(id, paintable);
		paintableToId.put(paintable, id);
	}

	public void unregisterPaintable(Paintable p) {
		idToPaintable.remove(paintableToId.get(p));
		paintableToId.remove(p);

		if (p instanceof HasWidgets) {
			unregisterChildPaintables((HasWidgets) p);
		}
	}

	public void unregisterChildPaintables(HasWidgets container) {
		Iterator it = container.iterator();
		while (it.hasNext()) {
			Widget w = (Widget) it.next();
			if (w instanceof Paintable) {
				this.unregisterPaintable((Paintable) w);
			}
			if (w instanceof HasWidgets) {
				unregisterChildPaintables((HasWidgets) w);
			}
		}
	}

	/**
	 * Returns Paintable element by its id
	 * 
	 * @param id
	 *            Paintable ID
	 */
	public Paintable getPaintable(String id) {
		return (Paintable) idToPaintable.get(id);
	}

	private void addVariableToQueue(String paintableId, String variableName,
			String encodedValue, boolean immediate, char type) {
		String id = paintableId + "_" + variableName + "_" + type;
		for (int i = 0; i < pendingVariables.size(); i += 2)
			if ((pendingVariables.get(i)).equals(id)) {
				pendingVariables.remove(i);
				pendingVariables.remove(i);
				break;
			}
		pendingVariables.add(id);
		pendingVariables.add(encodedValue);
		if (immediate)
			sendPendingVariableChanges();
	}

	public void sendPendingVariableChanges() {
		StringBuffer req = new StringBuffer();

		req.append("changes=");
		for (int i = 0; i < pendingVariables.size(); i++) {
			if (i > 0)
				req.append("\u0001");
			req.append(pendingVariables.get(i));
		}

		pendingVariables.clear();
		makeUidlRequest(req.toString());
	}

	private static native String escapeString(String value) /*-{
	 return encodeURIComponent(value);
	 }-*/;

	public void updateVariable(String paintableId, String variableName,
			String newValue, boolean immediate) {
		addVariableToQueue(paintableId, variableName, escapeString(newValue),
				immediate, 's');
	}

	public void updateVariable(String paintableId, String variableName,
			int newValue, boolean immediate) {
		addVariableToQueue(paintableId, variableName, "" + newValue, immediate,
				'i');
	}

	public void updateVariable(String paintableId, String variableName,
			long newValue, boolean immediate) {
		addVariableToQueue(paintableId, variableName, "" + newValue, immediate,
				'l');
	}

	public void updateVariable(String paintableId, String variableName,
			float newValue, boolean immediate) {
		addVariableToQueue(paintableId, variableName, "" + newValue, immediate,
				'f');
	}

	public void updateVariable(String paintableId, String variableName,
			double newValue, boolean immediate) {
		addVariableToQueue(paintableId, variableName, "" + newValue, immediate,
				'd');
	}

	public void updateVariable(String paintableId, String variableName,
			boolean newValue, boolean immediate) {
		addVariableToQueue(paintableId, variableName, newValue ? "true"
				: "false", immediate, 'b');
	}

	public void updateVariable(String paintableId, String variableName,
			Object[] values, boolean immediate) {
		StringBuffer buf = new StringBuffer();
		for (int i = 0; i < values.length; i++) {
			if (i > 0)
				buf.append(",");
			buf.append(escapeString(values[i].toString()));
		}
		addVariableToQueue(paintableId, variableName, buf.toString(),
				immediate, 'a');
	}

	public static Container getParentLayout(Widget component) {
		Widget parent = component.getParent();
		while (parent != null && !(parent instanceof Container))
			parent = parent.getParent();
		if (parent != null && ((Container) parent).hasChildComponent(component))
			return (Container) parent;
		return null;
	}

	/**
	 * Update generic component features.
	 * 
	 * <h2>Selecting correct implementation</h2>
	 * 
	 * <p>
	 * The implementation of a component depends on many properties, including
	 * styles, component features, etc. Sometimes the user changes those
	 * properties after the component has been created. Calling this method in
	 * the beginning of your updateFromUIDL -method automatically replaces your
	 * component with more appropriate if the requested implementation changes.
	 * </p>
	 * 
	 * <h2>Caption, icon, error messages and description</h2>
	 * 
	 * <p>
	 * Component can delegate management of caption, icon, error messages and
	 * description to parent layout. This is optional an should be decided by
	 * component author
	 * </p>
	 * 
	 * <h2>Component visibility and disabling</h2>
	 * 
	 * This method will manage component visibility automatically and if
	 * component is an instanceof FocusWidget, also handle component disabling
	 * when needed.
	 * 
	 * @param currentWidget
	 *            Current widget that might need replacement
	 * @param uidl
	 *            UIDL to be painted
	 * @param manageCaption
	 *            True if you want to delegate caption, icon, description and
	 *            error message management to parent.
	 * 
	 * @return Returns true iff no further painting is needed by caller
	 */
	public boolean updateComponent(Widget component, UIDL uidl,
			boolean manageCaption) {

		// If the server request that a cached instance should be used, do
		// nothing
		if (uidl.getBooleanAttribute("cached"))
			return true;

		// Switch to correct implementation if needed
		if (!widgetSet.isCorrectImplementation(component, uidl)) {
			Container parent = getParentLayout(component);
			if (parent != null) {
				Widget w = widgetSet.createWidget(uidl);
				parent.replaceChildComponent(component, w);
				registerPaintable(uidl.getId(), (Paintable) w);
				((Paintable) w).updateFromUIDL(uidl, this);
				return true;
			}
		}

		// Set captions
		// TODO Manage Error messages
		if (manageCaption) {
			Container parent = getParentLayout(component);
			if (parent != null)
				parent.updateCaption((Paintable) component, uidl);
		}

		// Visibility, Disabling and read-only status
		if (component instanceof FocusWidget) {
			boolean enabled = true;
			if (uidl.hasAttribute("disabled"))
				enabled = !uidl.getBooleanAttribute("disabled");
			else if (uidl.hasAttribute("readonly"))
				enabled = !uidl.getBooleanAttribute("readonly");
			((FocusWidget) component).setEnabled(enabled);
		} else {
			boolean enabled = true;
			if (uidl.hasAttribute("disabled"))
				enabled = !uidl.getBooleanAttribute("disabled");
			if (!enabled)
				component.addStyleName("i-disabled");
			else
				component.removeStyleName("i-disabled");
		}
		boolean visible = !uidl.getBooleanAttribute("invisible");
		component.setVisible(visible);
		if (!visible)
			return true;

		// add additional styles as css classes
		if (uidl.hasAttribute("style"))
			component.addStyleName(uidl.getStringAttribute("style"));

		return false;
	}

	/**
	 * Get either existing or new widget for given UIDL.
	 * 
	 * If corresponding paintable has been previously painted, return it.
	 * Otherwise create and register a new widget from UIDL. Caller must update
	 * the returned widget from UIDL after it has been connected to parent.
	 * 
	 * @param uidl
	 *            UIDL to create widget from.
	 * @return Either existing or new widget corresponding to UIDL.
	 */
	public Widget getWidget(UIDL uidl) {
		String id = uidl.getId();
		Widget w = (Widget) getPaintable(id);
		if (w != null)
			return w;
		w = widgetSet.createWidget(uidl);
		registerPaintable(id, (Paintable) w);
		return w;
	}

	public String getResource(String name) {
		return (String) resourcesMap.get(name);
	}

	/**
	 * Singleton method to get instance of app's context menu.
	 * 
	 * @return IContextMenu object
	 */
	public ContextMenu getContextMenu() {
		if (contextMenu == null) {
			contextMenu = new ContextMenu();
		}
		return contextMenu;
	}

	public void onFocus(Widget sender) {
		// TODO Auto-generated method stub

	}

	public void onLostFocus(Widget sender) {
		// TODO Auto-generated method stub

	}
}