JsProperties.java

/*
 * Copyright 2010 Manuel Carrasco Moñino. (manolo at apache/org) 
 * http://code.google.com/p/gwtupload
 * 
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 * 
 * 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 jsupload.client;

import com.google.gwt.core.client.JavaScriptObject;
import com.google.gwt.core.client.JsArrayString;

/**
 * @author Manolo Carrasco Moñino
 * 
 * <p>
 * An utility class for managing native javascript properties blocks.
 * </p>
 *
 */
public class JsProperties {

  private static class JSChangeClosureImpl implements JsChangeClosure {
    JavaScriptObject jsobject;

    JSChangeClosureImpl(JavaScriptObject o) {
      jsobject = o;
    }

    public void onChange(Object object) {
      onChangeImpl(jsobject, object);
    }

    public native void onChangeImpl(JavaScriptObject f, Object o)/*-{
      try {
        if (f && typeof f == 'function') f(o);
      } catch (e) {
        $wnd.console.log("JsUpload Error: " + e);
      }
    }-*/;
  }

  public static native JavaScriptObject createImpl(String properties) /*-{
    return eval(properties);
  }-*/;

  public static boolean getBoolean(JavaScriptObject jso, String name, boolean deFault) {
    String val = getImpl(jso, name, "" + deFault).toLowerCase();
    if (val.matches("^(1|true|on)$")) { return true; }
    if (val.matches("^(0|false|off)$")) { return false; }
    return deFault;
  }

  private static native boolean definedImpl(JavaScriptObject p, String name) /*-{
    return p && p[name] ? true : false;
  }-*/;

  private static native double getDoubleImpl(JavaScriptObject p, String name) /*-{
    return p && p[name] ? p[name]: 0;
  }-*/;

  private static native String getImpl(JavaScriptObject p, String name, String defa) /*-{
    return p && p[name] ? "" + p[name] : p && p[name] === false ? "false" : defa;
  }-*/;

  private static native JavaScriptObject getJSObjectImpl(JavaScriptObject p, String name) /*-{
    return p && p[name] ? p[name] : null ;
  }-*/;

  private static native JsArrayString keysImpl(JavaScriptObject p) /*-{
    var key, keys=[];
    if (p) for(key in p) keys.push("" + key); 
    return keys;
  }-*/;

  JavaScriptObject p = null;

  public JsProperties(JavaScriptObject p) {
    this.p = p;
  }

  public JsProperties(String properties) {
    String s = properties.replaceFirst("^[({]*(.*)[})]*$", "({$1})");
    s = "({" + s + "})";
    try {
      this.p = createImpl(s);
    } catch (Exception e) {
      this.p = createImpl("({exception: '" + e + "'})");
    }
  }

  public boolean defined(String name) {
    return definedImpl(p, name);
  }

  public String get(String name) {
    return getImpl(p, name, "");
  }

  public String get(String name, String deFault) {
    return getImpl(p, name, deFault);
  }

  public boolean getBoolean(String name) {
    return getBoolean(name, false);
  }

  public boolean getBoolean(String name, boolean deFault) {
    return getBoolean(p, name, deFault);
  }

  public JsChangeClosure getClosure(String name) {
    return new JSChangeClosureImpl(getJSObjectImpl(p, name));
  }

  public double getDouble(String name) {
    return (double) getDoubleImpl(p, name);
  }

  public float getFloat(String name) {
    return (float) getDoubleImpl(p, name);
  }

  public int getInt(String name) {
    return getInt(name, 0);
  }

  public int getInt(String name, int deFault) {
    String val = defined(name) ? get(name).replaceAll("[^\\d]", "") : "";
    if (val.length() == 0) { return deFault; }
    return Integer.valueOf(val);
  }

  public JsProperties getJsProperties(String name) {
    return new JsProperties(getJSObjectImpl(p, name));
  }

  public final String[] keys() {
    JsArrayString a = keysImpl(p);
    String[] ret = new String[a.length()];
    for (int i = 0; i < a.length(); i++) {
      ret[i] = "" + a.get(i);
    }
    return ret;
  }

  public String toString() {
    String ret = "";
    if (p == null) {
      ret = "null";
    } else {
      for (String k : keys()) {
        ret += k + ":" + get(k) + ",";
      }
    }
    return ret;
  }
}