/*
 * Copyright 2010 DTO Labs, Inc. (http://dtolabs.com)
 *
 *  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 com.dtolabs.client.utils;


import java.io.File;
import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;


public class BrowserLauncher {

    /**
     * The Java virtual machine that we are running on.  Actually, in most cases we only care about the operating
     * system, but some operating systems require us to switch on the VM.
     */
    private static int jvm;

    /**
     * The browser for the system
     */
    private static Object browser;

    /**
     * Caches whether any classes, methods, and fields that are not part of the JDK and need to be dynamically loaded at
     * runtime loaded successfully.
     * <p/>
     * Note that if this is <code>false</code>, <code>openURL()</code> will always return an IOException.
     */
    private static boolean loadedWithoutErrors;

    /**
     * The com.apple.mrj.MRJFileUtils class
     */
    private static Class mrjFileUtilsClass;

    /**
     * The com.apple.mrj.MRJOSType class
     */
    private static Class mrjOSTypeClass;

    /**
     * The com.apple.MacOS.AEDesc class
     */
    private static Class aeDescClass;

    /**
     * The <init>(int) method of com.apple.MacOS.AETarget
     */
    private static Constructor aeTargetConstructor;

    /**
     * The <init>(int, int, int) method of com.apple.MacOS.AppleEvent
     */
    private static Constructor appleEventConstructor;

    /**
     * The <init>(String) method of com.apple.MacOS.AEDesc
     */
    private static Constructor aeDescConstructor;

    /**
     * The findFolder method of com.apple.mrj.MRJFileUtils
     */
    private static Method findFolder;

    /**
     * The getFileCreator method of com.apple.mrj.MRJFileUtils
     */
    private static Method getFileCreator;

    /**
     * The getFileType method of com.apple.mrj.MRJFileUtils
     */
    private static Method getFileType;

    /**
     * The openURL method of com.apple.mrj.MRJFileUtils
     */
    private static Method openURL;

    /**
     * The makeOSType method of com.apple.MacOS.OSUtils
     */
    private static Method makeOSType;

    /**
     * The putParameter method of com.apple.MacOS.AppleEvent
     */
    private static Method putParameter;

    /**
     * The sendNoReply method of com.apple.MacOS.AppleEvent
     */
    private static Method sendNoReply;

    /**
     * Actually an MRJOSType pointing to the System Folder on a Macintosh
     */
    private static Object kSystemFolderType;

    /**
     * The keyDirectObject AppleEvent parameter type
     */
    private static Integer keyDirectObject;

    /**
     * The kAutoGenerateReturnID AppleEvent code
     */
    private static Integer kAutoGenerateReturnID;

    /**
     * The kAnyTransactionID AppleEvent code
     */
    private static Integer kAnyTransactionID;

    /**
     * The linkage object required for JDirect 3 on Mac OS X.
     */
    private static Object linkage;

    /**
     * The framework to reference on Mac OS X
     */
    private static final String JDirect_MacOSX = "/System/Library/Frameworks/Carbon.framework/Frameworks/HIToolbox.framework/HIToolbox";

    /**
     * JVM constant for MRJ 2.0
     */
    private static final int MRJ_2_0 = 0;

    /**
     * JVM constant for MRJ 2.1 or later
     */
    private static final int MRJ_2_1 = 1;

    /**
     * JVM constant for Java on Mac OS X 10.0 (MRJ 3.0)
     */
    private static final int MRJ_3_0 = 3;

    /**
     * JVM constant for MRJ 3.1
     */
    private static final int MRJ_3_1 = 4;

    /**
     * JVM constant for any Windows NT JVM
     */
    private static final int WINDOWS_NT = 5;

    /**
     * JVM constant for any Windows 9x JVM
     */
    private static final int WINDOWS_9x = 6;

    /**
     * JVM constant for any other platform
     */
    private static final int OTHER = -1;

    /**
     * The file type of the Finder on a Macintosh.  Hardcoding "Finder" would keep non-U.S. English systems from working
     * properly.
     */
    private static final String FINDER_TYPE = "FNDR";

    /**
     * The creator code of the Finder on a Macintosh, which is needed to send AppleEvents to the application.
     */
    private static final String FINDER_CREATOR = "MACS";

    /**
     * The name for the AppleEvent type corresponding to a GetURL event.
     */
    private static final String GURL_EVENT = "GURL";

    /**
     * The first parameter that needs to be passed into Runtime.exec() to open the default web browser on Windows.
     */
    private static final String FIRST_WINDOWS_PARAMETER = "/c";

    /**
     * The second parameter for Runtime.exec() on Windows.
     */
    private static final String SECOND_WINDOWS_PARAMETER = "start";

    /**
     * The third parameter for Runtime.exec() on Windows.  This is a "title" parameter that the command line expects.
     * Setting this parameter allows URLs containing spaces to work.
     */
    private static final String THIRD_WINDOWS_PARAMETER = "\"\"";

    /**
     * The shell parameters for Netscape that opens a given URL in an already-open copy of Netscape on many command-line
     * systems.
     */
    private static final String NETSCAPE_REMOTE_PARAMETER = "-remote";
    private static final String NETSCAPE_OPEN_PARAMETER_START = "'openURL(";
    private static final String NETSCAPE_OPEN_PARAMETER_END = ")'";

    /**
     * The message from any exception thrown throughout the initialization process.
     */
    private static String errorMessage;

    /**
     * An initialization block that determines the operating system and loads the necessary
     * runtime data.
     */
    static {
        loadedWithoutErrors = true;
        String osName = System.getProperty("os.name");
        if (osName.startsWith("Mac OS")) {
            String mrjVersion = System.getProperty("mrj.version");
            String majorMRJVersion = mrjVersion.substring(0, 3);
            try {
                double version = Double.valueOf(majorMRJVersion).doubleValue();
                if (version == 2) {
                    jvm = MRJ_2_0;
                } else if (version >= 2.1 && version < 3) {
                    // Assume that all 2.x versions of MRJ work the same.  MRJ 2.1 actually
                    // works via Runtime.exec() and 2.2 supports that but has an openURL() method
                    // as well that we currently ignore.
                    jvm = MRJ_2_1;
                } else if (version == 3.0) {
                    jvm = MRJ_3_0;
                } else if (version >= 3.1) {
                    // Assume that all 3.1 and later versions of MRJ work the same.
                    jvm = MRJ_3_1;
                } else {
                    loadedWithoutErrors = false;
                    errorMessage = "Unsupported MRJ version: " + version;
                }
            } catch (NumberFormatException nfe) {
                loadedWithoutErrors = false;
                errorMessage = "Invalid MRJ version: " + mrjVersion;
            }
        } else if (osName.startsWith("Windows")) {
            if (osName.indexOf("9") != -1) {
                jvm = WINDOWS_9x;
            } else {
                jvm = WINDOWS_NT;
            }
        } else {
            jvm = OTHER;
        }

        if (loadedWithoutErrors) {	// if we haven't hit any errors yet
            loadedWithoutErrors = loadClasses();
        }
    }

    /**
     * This class should be never be instantiated; this just ensures so.
     */
    private BrowserLauncher() { }

    /**
     * Called by a static initializer to load any classes, fields, and methods required at runtime to locate the user's
     * web browser.
     *
     * @return <code>true</code> if all intialization succeeded <code>false</code> if any portion of the initialization
     *         failed
     */
    private static boolean loadClasses() {
        switch (jvm) {
            case MRJ_2_0:
                try {
                    Class aeTargetClass = Class.forName("com.apple.MacOS.AETarget");
                    Class osUtilsClass = Class.forName("com.apple.MacOS.OSUtils");
                    Class appleEventClass = Class.forName("com.apple.MacOS.AppleEvent");
                    Class aeClass = Class.forName("com.apple.MacOS.ae");
                    aeDescClass = Class.forName("com.apple.MacOS.AEDesc");

                    aeTargetConstructor = aeTargetClass.getDeclaredConstructor(new Class[]{int.class});
                    appleEventConstructor
                    = appleEventClass.getDeclaredConstructor(
                        new Class[]{int.class, int.class, aeTargetClass, int.class, int.class});
                    aeDescConstructor = aeDescClass.getDeclaredConstructor(new Class[]{String.class});

                    makeOSType = osUtilsClass.getDeclaredMethod("makeOSType", new Class[]{String.class});
                    putParameter
                    = appleEventClass.getDeclaredMethod("putParameter", new Class[]{int.class, aeDescClass});
                    sendNoReply = appleEventClass.getDeclaredMethod("sendNoReply", new Class[]{});

                    Field keyDirectObjectField = aeClass.getDeclaredField("keyDirectObject");
                    keyDirectObject = (Integer) keyDirectObjectField.get(null);
                    Field autoGenerateReturnIDField = appleEventClass.getDeclaredField("kAutoGenerateReturnID");
                    kAutoGenerateReturnID = (Integer) autoGenerateReturnIDField.get(null);
                    Field anyTransactionIDField = appleEventClass.getDeclaredField("kAnyTransactionID");
                    kAnyTransactionID = (Integer) anyTransactionIDField.get(null);
                } catch (ClassNotFoundException cnfe) {
                    errorMessage = cnfe.getMessage();
                    return false;
                } catch (NoSuchMethodException nsme) {
                    errorMessage = nsme.getMessage();
                    return false;
                } catch (NoSuchFieldException nsfe) {
                    errorMessage = nsfe.getMessage();
                    return false;
                } catch (IllegalAccessException iae) {
                    errorMessage = iae.getMessage();
                    return false;
                }
                break;
            case MRJ_2_1:
                try {
                    mrjFileUtilsClass = Class.forName("com.apple.mrj.MRJFileUtils");
                    mrjOSTypeClass = Class.forName("com.apple.mrj.MRJOSType");
                    Field systemFolderField = mrjFileUtilsClass.getDeclaredField("kSystemFolderType");
                    kSystemFolderType = systemFolderField.get(null);
                    findFolder = mrjFileUtilsClass.getDeclaredMethod("findFolder", new Class[]{mrjOSTypeClass});
                    getFileCreator = mrjFileUtilsClass.getDeclaredMethod("getFileCreator", new Class[]{File.class});
                    getFileType = mrjFileUtilsClass.getDeclaredMethod("getFileType", new Class[]{File.class});
                } catch (ClassNotFoundException cnfe) {
                    errorMessage = cnfe.getMessage();
                    return false;
                } catch (NoSuchFieldException nsfe) {
                    errorMessage = nsfe.getMessage();
                    return false;
                } catch (NoSuchMethodException nsme) {
                    errorMessage = nsme.getMessage();
                    return false;
                } catch (SecurityException se) {
                    errorMessage = se.getMessage();
                    return false;
                } catch (IllegalAccessException iae) {
                    errorMessage = iae.getMessage();
                    return false;
                }
                break;
            case MRJ_3_0:
                try {
                    Class linker = Class.forName("com.apple.mrj.jdirect.Linker");
                    Constructor constructor = linker.getConstructor(new Class[]{Class.class});
                    linkage = constructor.newInstance(new Object[]{BrowserLauncher.class});
                } catch (ClassNotFoundException cnfe) {
                    errorMessage = cnfe.getMessage();
                    return false;
                } catch (NoSuchMethodException nsme) {
                    errorMessage = nsme.getMessage();
                    return false;
                } catch (InvocationTargetException ite) {
                    errorMessage = ite.getMessage();
                    return false;
                } catch (InstantiationException ie) {
                    errorMessage = ie.getMessage();
                    return false;
                } catch (IllegalAccessException iae) {
                    errorMessage = iae.getMessage();
                    return false;
                }
                break;
            case MRJ_3_1:
                try {
                    mrjFileUtilsClass = Class.forName("com.apple.mrj.MRJFileUtils");
                    openURL = mrjFileUtilsClass.getDeclaredMethod("openURL", new Class[]{String.class});
                } catch (ClassNotFoundException cnfe) {
                    errorMessage = cnfe.getMessage();
                    return false;
                } catch (NoSuchMethodException nsme) {
                    errorMessage = nsme.getMessage();
                    return false;
                }
                break;
            default:
                break;
        }
        return true;
    }

    /**
     * Attempts to locate the default web browser on the local system.  Caches results so it only locates the browser
     * once for each use of this class per JVM instance.
     *
     * @return The browser for the system.  Note that this may not be what you would consider to be a standard web
     *         browser; instead, it's the application that gets called to open the default web browser.  In some cases,
     *         this will be a non-String object that provides the means of calling the default browser.
     */
    private static Object locateBrowser() {
        if (browser != null) {
            return browser;
        }
        switch (jvm) {
            case MRJ_2_0:
                try {
                    Integer finderCreatorCode = (Integer) makeOSType.invoke(null, new Object[]{FINDER_CREATOR});
                    Object aeTarget = aeTargetConstructor.newInstance(new Object[]{finderCreatorCode});
                    Integer gurlType = (Integer) makeOSType.invoke(null, new Object[]{GURL_EVENT});
                    Object appleEvent = appleEventConstructor.newInstance(
                        new Object[]{gurlType, gurlType, aeTarget, kAutoGenerateReturnID, kAnyTransactionID});
                    // Don't set browser = appleEvent because then the next time we call
                    // locateBrowser(), we'll get the same AppleEvent, to which we'll already have
                    // added the relevant parameter. Instead, regenerate the AppleEvent every time.
                    // There's probably a way to do this better; if any has any ideas, please let
                    // me know.
                    return appleEvent;
                } catch (IllegalAccessException iae) {
                    browser = null;
                    errorMessage = iae.getMessage();
                    return browser;
                } catch (InstantiationException ie) {
                    browser = null;
                    errorMessage = ie.getMessage();
                    return browser;
                } catch (InvocationTargetException ite) {
                    browser = null;
                    errorMessage = ite.getMessage();
                    return browser;
                }
            case MRJ_2_1:
                File systemFolder;
                try {
                    systemFolder = (File) findFolder.invoke(null, new Object[]{kSystemFolderType});
                } catch (IllegalArgumentException iare) {
                    browser = null;
                    errorMessage = iare.getMessage();
                    return browser;
                } catch (IllegalAccessException iae) {
                    browser = null;
                    errorMessage = iae.getMessage();
                    return browser;
                } catch (InvocationTargetException ite) {
                    browser = null;
                    errorMessage = ite.getTargetException().getClass() + ": " + ite.getTargetException().getMessage();
                    return browser;
                }
                String[] systemFolderFiles = systemFolder.list();
                // Avoid a FilenameFilter because that can't be stopped mid-list
                for (int i = 0; i < systemFolderFiles.length; i++) {
                    try {
                        File file = new File(systemFolder, systemFolderFiles[i]);
                        if (!file.isFile()) {
                            continue;
                        }
                        // We're looking for a file with a creator code of 'MACS' and
                        // a type of 'FNDR'.  Only requiring the type results in non-Finder
                        // applications being picked up on certain Mac OS 9 systems,
                        // especially German ones, and sending a GURL event to those
                        // applications results in a logout under Multiple Users.
                        Object fileType = getFileType.invoke(null, new Object[]{file});
                        if (FINDER_TYPE.equals(fileType.toString())) {
                            Object fileCreator = getFileCreator.invoke(null, new Object[]{file});
                            if (FINDER_CREATOR.equals(fileCreator.toString())) {
                                browser = file.toString();	// Actually the Finder, but that's OK
                                return browser;
                            }
                        }
                    } catch (IllegalArgumentException iare) {
                        BrowserLauncher.browser = browser;
                        errorMessage = iare.getMessage();
                        return null;
                    } catch (IllegalAccessException iae) {
                        browser = null;
                        errorMessage = iae.getMessage();
                        return browser;
                    } catch (InvocationTargetException ite) {
                        browser = null;
                        errorMessage = ite.getTargetException().getClass() + ": "
                                       + ite.getTargetException().getMessage();
                        return browser;
                    }
                }
                browser = null;
                break;
            case MRJ_3_0:
            case MRJ_3_1:
                browser = "";	// Return something non-null
                break;
            case WINDOWS_NT:
                browser = "cmd.exe";
                break;
            case WINDOWS_9x:
                browser = "command.com";
                break;
            case OTHER:
            default:
                browser = "netscape";
                break;
        }
        return browser;
    }

    /**
     * Attempts to open the default web browser to the given URL.
     *
     * @param url The URL to open
     *
     * @throws IOException If the web browser could not be located or does not run
     */
    public static void openURL(String url, String browser) throws IOException {
        if (browser == null) {
            BrowserLauncher.openURL(url);
        }
//		if (browser.indexOf(" ") > -1) { //has blank spaces
//			if (! browser.startsWith("\"")) browser = "\"" + browser;
//			if (! browser.endsWith("\"")) browser = browser + "\"";
//		}
        if (browser.indexOf("%1") > -1) {
            String command = browser.substring(0, browser.indexOf("%1")) + url
                             + browser.substring(browser.indexOf("%1") + 2);
            Process process = Runtime.getRuntime().exec(new String[]{command});
        } else {
            Process process = Runtime.getRuntime().exec(new String[]{browser, url});
        }
//		try {
//			process.waitFor();
//			process.exitValue();
//		} catch (InterruptedException ie) {
//			throw new IOException("InterruptedException while launching browser: " + ie.getMessage());
//		}
    }

    /**
     * Attempts to open the web browser to the given URL.
     *
     * @param url         The URL to open
     * @param userBrowser The web browser command-line argument
     *
     * @throws IOException If the web browser could not be located or does not run
     */
    public static void openURL(String url) throws IOException {
        if (!loadedWithoutErrors) {
            throw new IOException("Exception in finding browser: " + errorMessage);
        }
        Object browser = locateBrowser();
        if (browser == null) {
            throw new IOException("Unable to locate browser: " + errorMessage);
        }

        switch (jvm) {
            case MRJ_2_0:
                Object aeDesc = null;
                try {
                    aeDesc = aeDescConstructor.newInstance(new Object[]{url});
                    putParameter.invoke(browser, new Object[]{keyDirectObject, aeDesc});
                    sendNoReply.invoke(browser, new Object[]{});
                } catch (InvocationTargetException ite) {
                    throw new IOException("InvocationTargetException while creating AEDesc: " + ite.getMessage());
                } catch (IllegalAccessException iae) {
                    throw new IOException("IllegalAccessException while building AppleEvent: " + iae.getMessage());
                } catch (InstantiationException ie) {
                    throw new IOException("InstantiationException while creating AEDesc: " + ie.getMessage());
                } finally {
                    aeDesc = null;	// Encourage it to get disposed if it was created
                    browser = null;	// Ditto
                }
                break;
            case MRJ_2_1:
                Runtime.getRuntime().exec(new String[]{(String) browser, url});
                break;
            case MRJ_3_0:
                int[] instance = new int[1];
                int result = ICStart(instance, 0);
                if (result == 0) {
                    int[] selectionStart = new int[]{0};
                    byte[] urlBytes = url.getBytes();
                    int[] selectionEnd = new int[]{urlBytes.length};
                    result = ICLaunchURL(instance[0], new byte[]{0}, urlBytes,
                                         urlBytes.length, selectionStart,
                                         selectionEnd);
                    if (result == 0) {
                        // Ignore the return value; the URL was launched successfully
                        // regardless of what happens here.
                        ICStop(instance);
                    } else {
                        throw new IOException("Unable to launch URL: " + result);
                    }
                } else {
                    throw new IOException("Unable to create an Internet Config instance: " + result);
                }
                break;
            case MRJ_3_1:
                try {
                    openURL.invoke(null, new Object[]{url});
                } catch (InvocationTargetException ite) {
                    throw new IOException("InvocationTargetException while calling openURL: " + ite.getMessage());
                } catch (IllegalAccessException iae) {
                    throw new IOException("IllegalAccessException while calling openURL: " + iae.getMessage());
                }
                break;
            case WINDOWS_NT:
            case WINDOWS_9x:
                // Add quotes around the URL to allow ampersands and other special
                // characters to work.
                Process process = Runtime.getRuntime().exec(new String[]{
                    (String) browser,
                    FIRST_WINDOWS_PARAMETER,
                    SECOND_WINDOWS_PARAMETER,
                    THIRD_WINDOWS_PARAMETER,
                    '"' + url + '"'
                });
                // This avoids a memory leak on some versions of Java on Windows.
                // That's hinted at in <http://developer.java.sun.com/developer/qow/archive/68/>.
                try {
                    process.waitFor();
                    process.exitValue();
                } catch (InterruptedException ie) {
                    throw new IOException("InterruptedException while launching browser: " + ie.getMessage());
                }
                break;
            case OTHER:
                // Assume that we're on Unix and that Netscape is installed

                // First, attempt to open the URL in a currently running session of Netscape
                process = Runtime.getRuntime().exec(new String[]{
                    (String) browser,
                    NETSCAPE_REMOTE_PARAMETER,
                    NETSCAPE_OPEN_PARAMETER_START +
                    url +
                    NETSCAPE_OPEN_PARAMETER_END
                });
                try {
                    int exitCode = process.waitFor();
                    if (exitCode != 0) {	// if Netscape was not open
                        Runtime.getRuntime().exec(new String[]{(String) browser, url});
                    }
                } catch (InterruptedException ie) {
                    throw new IOException("InterruptedException while launching browser: " + ie.getMessage());
                }
                break;
            default:
                // This should never occur, but if it does, we'll try the simplest thing possible
                Runtime.getRuntime().exec(new String[]{(String) browser, url});
                break;
        }
    }

    /**
     * Methods required for Mac OS X.  The presence of native methods does not cause any problems on other platforms.
     */
    private native static int ICStart(int[] instance, int signature);

    private native static int ICStop(int[] instance);

    private native static int ICLaunchURL(int instance,
                                          byte[] hint,
                                          byte[] data,
                                          int len,
                                          int[] selectionStart,
                                          int[] selectionEnd);

    static public void main(String[] args) throws Exception {
//		BrowserLauncher.openURL("http://thinfeeder.sf.net", "\"C:\\Arquivos de programas\\Mozilla Firefox\\firefox.exe\" -remote \"openURL(%1,new-tab)\"");
//		BrowserLauncher.openURL("http://thinfeeder.sf.net", "\"C:\\Arquivos de programas\\Mozilla Firefox\\firefox.exe\"");
//		BrowserLauncher.openURL("http://thinfeeder.sf.net", "\"C:\\Arquivos de programas\\Mozilla Firefox\\firefox.exe\" -remote \"openurl(%1)\"");
        BrowserLauncher.openURL("http://thinfeeder.sf.net",
                                "\"C:\\Arquivos de programas\\Mozilla Firefox\\firefox.exe\" -P default \"%1\"");
    }
}