package org.argeo.cms.web;

import java.util.Dictionary;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

import org.argeo.api.cms.CmsApp;
import org.argeo.api.cms.CmsAppListener;
import org.argeo.api.cms.CmsEventBus;
import org.argeo.api.cms.CmsLog;
import org.argeo.api.cms.ux.CmsTheme;
import org.argeo.api.cms.ux.CmsView;
import org.argeo.cms.swt.CmsSwtUtils;
import org.argeo.cms.util.LangUtils;
import org.eclipse.rap.rwt.RWT;
import org.eclipse.rap.rwt.application.Application;
import org.eclipse.rap.rwt.application.Application.OperationMode;
import org.eclipse.rap.rwt.application.ApplicationConfiguration;
import org.eclipse.rap.rwt.application.ExceptionHandler;
import org.eclipse.rap.rwt.client.WebClient;
import org.eclipse.swt.widgets.Display;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceRegistration;

/** An RWT web app integrating with a {@link CmsApp}. */
public class CmsWebApp implements ApplicationConfiguration, ExceptionHandler, CmsAppListener {
	private final static CmsLog log = CmsLog.getLog(CmsWebApp.class);

	private BundleContext bundleContext;
	private CmsApp cmsApp;

	private CmsEventBus cmsEventBus;

	private ServiceRegistration<ApplicationConfiguration> rwtAppReg;

	private final static String CONTEXT_NAME = "contextName";
	private String contextName;

	private final static String FAVICON_PNG = "favicon.png";

	public void init(BundleContext bundleContext, Map<String, String> properties) {
		this.bundleContext = bundleContext;
		contextName = properties.get(CONTEXT_NAME);
		if (cmsApp != null) {
			if (cmsApp.allThemesAvailable())
				publishWebApp();
		}
	}

	public void destroy(BundleContext bundleContext, Map<String, String> properties) {
		if (cmsApp != null) {
			cmsApp.removeCmsAppListener(this);
			cmsApp = null;
		}
	}

	@Override
	public void configure(Application application) {
		// TODO make it configurable?
		// SWT compatibility is required for:
		// - Browser.execute()
		// - blocking dialogs
		application.setOperationMode(OperationMode.SWT_COMPATIBILITY);
		for (String uiName : cmsApp.getUiNames()) {
			CmsTheme theme = cmsApp.getTheme(uiName);
			if (theme != null)
				WebThemeUtils.apply(application, theme);
		}

		Map<String, String> properties = new HashMap<>();
		addEntryPoints(application, properties);
		application.setExceptionHandler(this);
	}

	@Override
	public void handleException(Throwable throwable) {
		Display display = Display.getCurrent();
		if (display != null && !display.isDisposed()) {
			CmsView cmsView = CmsSwtUtils.getCmsView(display.getActiveShell());
			cmsView.exception(throwable);
		} else {
			log.error("Unexpected exception outside an UI thread", throwable);
		}

	}

	protected void addEntryPoints(Application application, Map<String, String> commonProperties) {
		for (String uiName : cmsApp.getUiNames()) {
			Map<String, String> properties = new HashMap<>(commonProperties);
			CmsTheme theme = cmsApp.getTheme(uiName);
			if (theme != null) {
				properties.put(WebClient.THEME_ID, theme.getThemeId());
				properties.put(WebClient.HEAD_HTML, theme.getHtmlHeaders());
				properties.put(WebClient.BODY_HTML, theme.getBodyHtml());
				Set<String> imagePaths = theme.getImagesPaths();
				if (imagePaths.contains(FAVICON_PNG)) {
					properties.put(WebClient.FAVICON, FAVICON_PNG);
				}
			} else {
				properties.put(WebClient.THEME_ID, RWT.DEFAULT_THEME_ID);
			}
			String entryPointName = !uiName.equals("") ? "/" + uiName : "/";
			application.addEntryPoint(entryPointName, () -> {
				CmsWebEntryPoint entryPoint = new CmsWebEntryPoint(this, uiName);
				return entryPoint;
			}, properties);
			if (log.isDebugEnabled())
				log.debug("Added web entry point " + (contextName != null ? "/" + contextName : "") + entryPointName);
		}
//		if (log.isDebugEnabled())
//			log.debug("Published CMS web app /" + (contextName != null ? contextName : ""));
	}

	public CmsApp getCmsApp() {
		return cmsApp;
	}

	BundleContext getBundleContext() {
		return bundleContext;
	}

	public void setCmsApp(CmsApp cmsApp) {
		this.cmsApp = cmsApp;
//		this.cmsAppId = properties.get(Constants.SERVICE_PID);
		this.cmsApp.addCmsAppListener(this);
	}

	public void unsetCmsApp(CmsApp cmsApp, Map<String, String> properties) {
		String contextName = properties.get(CmsApp.CONTEXT_NAME_PROPERTY);
		if (!contextName.equals(this.contextName))
			return;
		if (this.cmsApp != null) {
			this.cmsApp.removeCmsAppListener(this);
		}
		if (rwtAppReg != null)
			rwtAppReg.unregister();
		this.cmsApp = null;
	}

	@Override
	public void themingUpdated() {
		if (cmsApp != null && cmsApp.allThemesAvailable())
			publishWebApp();
	}

	protected void publishWebApp() {
		Dictionary<String, Object> regProps = LangUtils.dict(CONTEXT_NAME, contextName);
		if (rwtAppReg != null)
			rwtAppReg.unregister();
		if (bundleContext != null) {
			rwtAppReg = bundleContext.registerService(ApplicationConfiguration.class, this, regProps);
			log.info("Publishing CMS web app /" + (contextName != null ? contextName : "") + " ...");
		}
	}

	public void setCmsEventBus(CmsEventBus cmsEventBus) {
		this.cmsEventBus = cmsEventBus;
	}

	public CmsEventBus getCmsEventBus() {
		return cmsEventBus;
	}

	public void setContextName(String contextName) {
		this.contextName = contextName;
	}

}