#// Usage: jjs -fx jsonviewer.js
// or
//        jjs -fx jsonviewer.js -- <url-of-json-doc>

/*
 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 
 *   - Neither the name of Oracle nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

if (! $OPTIONS._fx) {
    print("Usage: jjs -fx jsonviewer.js -- <url-of-json-doc>");
    exit(1);
}

// This example downloads a JSON file from a URL and
// shows the same as a JavaFX tree view.

// Using JavaFX from Nashorn. See also:
// http://docs.oracle.com/javase/8/docs/technotes/guides/scripting/nashorn/javafx.html

// JavaFX classes used
var StackPane = Java.type("javafx.scene.layout.StackPane");
var Scene     = Java.type("javafx.scene.Scene");
var TreeItem  = Java.type("javafx.scene.control.TreeItem");
var TreeView  = Java.type("javafx.scene.control.TreeView");

// read text content of a URL
function readTextFromURL(url) {
    // equivalent to 
    // 
    //    import java.io.*;
    //    import java.net.*;
    //    import java.lang.StringBuffer;
    //
    // only inside the 'with' statement
    with (new JavaImporter(java.io,
        java.net,
        java.lang.StringBuilder)) {
        var buf = new StringBuilder();
        var u = new URL(url);
        var reader = new BufferedReader(
            new InputStreamReader(u.openStream()));
        var line = null;
        try {
            while ((line = reader.readLine()) != null)
                buf.append(line).append('\n');
        } finally {
            reader.close();
        }

        return buf.toString();
    }
}

// Create a javafx TreeItem to view a script object
function treeItemForObject(obj, name) {
    var item = new TreeItem(name);
    for (var prop in obj) {
       var node = obj[prop];
       if (typeof node == 'object') {
           if (node == null) {
               // skip nulls
               continue;
           }

           if (Array.isArray(node) && node.length == 0) {
               // skip empty arrays
               continue;
           }

           var subitem = treeItemForObject(node, prop);
       } else {
           var subitem = new TreeItem(prop + ": " + node);
       }
       item.children.add(subitem);
    }
    return item;
}

var DEFAULT_URL = "http://api.openweathermap.org/data/2.5/forecast/daily?q=Chennai&amp;mode=json&amp;units=metric&amp;cnt=7`";

var url = arguments.length == 0? DEFAULT_URL : arguments[0];
var obj = JSON.parse(readTextFromURL(url));

// JavaFX start method
function start(stage) {
    stage.title = "JSON Viewer";
    var rootItem = treeItemForObject(obj, url);
    var tree = new TreeView(rootItem);
    var root = new StackPane();
    root.children.add(tree);
    stage.scene = new Scene(root, 300, 450);
    stage.show();
}