Issue 1423. Enhanced welcome page.

editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/intro/SampleDescriptionHelper.java

Index: editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/intro/SampleDescriptionHelper.java
diff --git a/editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/intro/SampleDescriptionHelper.java b/editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/intro/SampleDescriptionHelper.java
new file mode 100644
index 0000000000000000000000000000000000000000..4f6cde6184ca2dd66595f28245210babc5f07a6c
--- /dev/null
+++ b/editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/intro/SampleDescriptionHelper.java
@@ -0,0 +1,159 @@
+/*
+ * Copyright 2012 Google Inc.
+ * 
+ * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ * 
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.google.dart.tools.ui.internal.intro;
+
+import com.google.common.collect.Lists;
+import com.google.dart.tools.core.DartCore;
+
+import org.xml.sax.Attributes;
+import org.xml.sax.SAXException;
+import org.xml.sax.helpers.DefaultHandler;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.util.Collections;
+import java.util.List;
+
+import javax.xml.parsers.SAXParser;
+import javax.xml.parsers.SAXParserFactory;
+
+/**
+ * Helper for providing {@link SampleDescription}s.
+ */
+public final class SampleDescriptionHelper {
+  /**
+   * @return all {@link SampleDescription} from the "samples" directory.
+   */
+  public static List<SampleDescription> getDescriptions() throws Exception {
+    List<SampleDescription> descriptions = Lists.newArrayList();
+    File samplesDirectory = getSamplesDirectory();
+    scanFolder(descriptions, samplesDirectory);
+    Collections.sort(descriptions);
+    return descriptions;
+  }
+
+  /**
+   * Attempts to add {@link SampleDescription} for given directory.
+   * 
+   * @return <code>true</code> if {@link SampleDescription} was added.
+   */
+  private static boolean addDescription(final List<SampleDescription> descriptions,
+      final File directory) {
+    // attempt to find logo
+    final File logoFile = new File(directory, "logo.png");
+    if (!logoFile.exists() || !logoFile.isFile()) {
+      return false;
+    }
+    // attempt to find description
+    final boolean descriptionAdded[] = {false};
+    File descriptionFile = new File(directory, "sample.xml");
+    if (descriptionFile.exists() && descriptionFile.isFile()) {
+      try {
+        SAXParserFactory factory = SAXParserFactory.newInstance();
+        SAXParser saxParser = factory.newSAXParser();
+        DefaultHandler handler = new DefaultHandler() {
+          private StringBuilder sb = new StringBuilder();
+          private String name;
+          private String filePath;
+          private String descriptionText;
+          private int order;
+
+          @Override
+          public void characters(char[] ch, int start, int length) throws SAXException {
+            sb.append(ch, start, length);
+          }
+
+          @Override
+          public void endElement(String uri, String localName, String qName) throws SAXException {
+            if (qName.equals("description")) {
+              descriptionText = sb.toString();
+            }
+            if (qName.equals("sample") && filePath != null && name != null
+                && descriptionText != null) {
+              descriptions.add(new SampleDescription(directory, filePath, name, descriptionText,
+                  logoFile, order));
+              descriptionAdded[0] = true;
+            }
+          }
+
+          @Override
+          public void startElement(String uri, String localName, String qName, Attributes attributes)
+              throws SAXException {
+            sb.setLength(0);
+            if (qName.equals("sample")) {
+              name = attributes.getValue("name");
+              filePath = attributes.getValue("file");
+              {
+                order = Integer.MIN_VALUE;
+                String orderString = attributes.getValue("order");
+                if (orderString != null) {
+                  try {
+                    order = Integer.parseInt(orderString);
+                  } catch (NumberFormatException e) {
+                  }
+                }
+              }
+            }
+          }
+        };
+        FileInputStream is = new FileInputStream(descriptionFile);
+        try {
+          saxParser.parse(is, handler);
+        } finally {
+          is.close();
+        }
+      } catch (Throwable e) {
+        DartCore.logError(e);
+      }
+    }
+    // may be added
+    return descriptionAdded[0];
+  }
+
+  /**
+   * @return the {@link File} of the "samples" directory.
+   */
+  private static File getSamplesDirectory() throws Exception {
+    // try to get "development" path
+    {
+      String devSamplesPath = System.getProperty("dartEditor.development.samplesPath");

[danrubel, 2012/02/07 06:00:46]

File installDir = new File(Platform.getInstallLocation().getURL().getFile());
File samples = new File(installDir, "samples");

[scheglov, 2012/02/08 16:07:22]

OK for "user" branch.

But for development branch I still have to keep existing externally provided
"samples" location. I keep Eclipse outside of "git" repository, so
getInstallLocation() returns directory with "plugins", there are no....

OK, I've solved problem by using symbolic link from my Eclipse folder to actual
"samples" folder.

+      if (devSamplesPath != null) {
+        return new File(devSamplesPath);
+      }
+    }
+    // OK, get use path
+    File eclipsePath = new File(".").getCanonicalFile();
+    return new File(eclipsePath, "samples");
+  }
+
+  /**
+   * Attempts to find sample description in the given directory, otherwise scans recursively.
+   */
+  private static void scanFolder(List<SampleDescription> descriptions, File directory)
+      throws Exception {
+    // ignore not directories
+    if (!directory.exists() || !directory.isDirectory()) {
+      return;
+    }
+    // attempt to add description
+    boolean added = addDescription(descriptions, directory);
+    if (added) {
+      return;
+    }
+    // scan children
+    for (File child : directory.listFiles()) {
+      scanFolder(descriptions, child);
+    }
+  }
+}