Improve callback support

[gpl/argeo-suite.git] / swt / org.argeo.app.geo.swt / src / org / argeo / app / geo / swt / SwtJSMapPart.java

diff --git a/swt/org.argeo.app.geo.swt/src/org/argeo/app/geo/swt/SwtJSMapPart.java b/swt/org.argeo.app.geo.swt/src/org/argeo/app/geo/swt/SwtJSMapPart.java
new file mode 100644 (file)
index 0000000..09848f9
--- /dev/null
+++ b/swt/org.argeo.app.geo.swt/src/org/argeo/app/geo/swt/SwtJSMapPart.java
@@ -0,0 +1,152 @@
+package org.argeo.app.geo.swt;
+
+import java.util.Locale;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
+import java.util.function.Consumer;
+
+import org.argeo.api.cms.CmsLog;
+import org.argeo.app.geo.ux.JsImplementation;
+import org.argeo.app.geo.ux.MapPart;
+import org.argeo.cms.swt.CmsSwtUtils;
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.browser.Browser;
+import org.eclipse.swt.browser.BrowserFunction;
+import org.eclipse.swt.browser.ProgressEvent;
+import org.eclipse.swt.browser.ProgressListener;
+import org.eclipse.swt.layout.GridData;
+import org.eclipse.swt.widgets.Composite;
+
+/**
+ * An SWT implementation of {@link MapPart} based on JavaScript execute in a
+ * {@link Browser} control.
+ */
+public class SwtJSMapPart extends Composite implements MapPart {
+       static final long serialVersionUID = 2713128477504858552L;
+
+       private final static CmsLog log = CmsLog.getLog(SwtJSMapPart.class);
+
+       private final static String GLOBAL_THIS_ = "globalThis.";
+
+       private final Browser browser;
+
+       private final CompletableFuture<Boolean> pageLoaded = new CompletableFuture<>();
+
+       private String jsImplementation = JsImplementation.OPENLAYERS_MAP_PART.getJsClass();
+       private String mapVar = "argeoMap";
+
+       public SwtJSMapPart(Composite parent, int style) {
+               super(parent, style);
+               parent.setLayout(CmsSwtUtils.noSpaceGridLayout());
+               setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
+               setLayout(CmsSwtUtils.noSpaceGridLayout());
+
+               browser = new Browser(this, SWT.BORDER);
+               browser.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
+
+               browser.setUrl("/pkg/org.argeo.app.geo.js/index.html");
+               browser.addProgressListener(new ProgressListener() {
+                       static final long serialVersionUID = 1L;
+
+                       @Override
+                       public void completed(ProgressEvent event) {
+                               try {
+                                       // create map
+                                       browser.execute(getJsMapVar() + " = new " + jsImplementation + "();");
+                                       pageLoaded.complete(true);
+                               } catch (Exception e) {
+                                       log.error("Cannot create map in browser", e);
+                                       pageLoaded.complete(false);
+                               }
+                       }
+
+                       @Override
+                       public void changed(ProgressEvent event) {
+                       }
+               });
+       }
+
+       /*
+        * MapPart.js METHODS
+        */
+
+       @Override
+       public void addPoint(double lng, double lat, String style) {
+               callMapMethod("addPoint(%f, %f, %s)", lng, lat, style == null ? "'default'" : style);
+       }
+
+       @Override
+       public void addUrlLayer(String url, GeoFormat format) {
+               callMapMethod("addUrlLayer('%s', '%s')", url, format.name());
+       }
+
+       @Override
+       public void setZoom(int zoom) {
+               callMapMethod("setZoom(%d)", zoom);
+       }
+
+       @Override
+       public void setCenter(double lng, double lat) {
+               callMapMethod("setCenter(%f, %f)", lng, lat);
+       }
+
+       protected CompletionStage<Object> callMapMethod(String methodCall, Object... args) {
+               return callMethod(getJsMapVar(), methodCall, args);
+       }
+
+       protected CompletionStage<Object> callMethod(String jsObject, String methodCall, Object... args) {
+               return evaluate(jsObject + '.' + methodCall, args);
+       }
+
+       private String getJsMapVar() {
+               return GLOBAL_THIS_ + mapVar;
+       }
+
+       /**
+        * Execute this JavaScript on the client side after making sure that the page
+        * has been loaded and the map object has been created.
+        * 
+        * @param js   the JavaScript code, possibly formatted according to
+        *             {@link String#format}, with {@link Locale#ROOT} as locale (for
+        *             stability of decimal separator, as expected by JavaScript.
+        * @param args the optional arguments of
+        *             {@link String#format(String, Object...)}
+        */
+       protected CompletionStage<Object> evaluate(String js, Object... args) {
+               CompletableFuture<Object> res = pageLoaded.thenApply((ready) -> {
+                       if (!ready)
+                               throw new IllegalStateException("Map " + mapVar + " is not initialised.");
+                       Object result = browser.evaluate(String.format(Locale.ROOT, js, args));
+                       return result;
+               });
+               return res.minimalCompletionStage();
+       }
+
+       /*
+        * CALLBACKS
+        */
+       public void onFeatureSelected(Consumer<FeatureSelectedEvent> toDo) {
+               addCallback("FeatureSelected", (arr) -> toDo.accept(new FeatureSelectedEvent((String) arr[0])));
+       }
+
+       public void onFeatureSingleClick(Consumer<FeatureSingleClickEvent> toDo) {
+               addCallback("FeatureSingleClick", (arr) -> toDo.accept(new FeatureSingleClickEvent((String) arr[0])));
+       }
+
+       protected void addCallback(String suffix, Consumer<Object[]> toDo) {
+               pageLoaded.thenAccept((ready) -> {
+                       // browser functions must be directly on window (RAP specific)
+                       new BrowserFunction(browser, mapVar + "__on" + suffix) {
+
+                               @Override
+                               public Object function(Object[] arguments) {
+                                       toDo.accept(arguments);
+                                       return null;
+                               }
+
+                       };
+                       browser.execute(getJsMapVar() + ".callbacks['on" + suffix + "']=window." + mapVar + "__on" + suffix + ";");
+                       callMethod(mapVar, "enable" + suffix + "()");
+               });
+       }
+}