/**
 * MailArchiver is an application that provides services for storing and managing e-mail messages through a Web Services SOAP interface.
 * Copyright (C) 2012  Marcio Andre Scholl Levien and Fernando Alberto Reuter Wendt and Jose Ronaldo Nogueira Fonseca Junior
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/******************************************************************************\
*
*  This product was developed by
*
*        SERVIÇO FEDERAL DE PROCESSAMENTO DE DADOS (SERPRO),
*
*  a government company established under Brazilian law (5.615/70),
*  at Department of Development of Porto Alegre.
*
\******************************************************************************/

package serpro.mailarchiver.util.bshcommands;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.io.UnsupportedEncodingException;

import javax.annotation.PostConstruct;

import bsh.CallStack;
import bsh.EvalError;
import bsh.Interpreter;
import bsh.InterpreterError;
import bsh.ParseException;
import bsh.TargetError;

import com.eventrouter.SubscriptionRegistry;
import com.eventrouter.annotation.AnnotationProcessor;
import com.eventrouter.annotation.Subscribe;

import org.springframework.beans.factory.annotation.Configurable;

import com.vaadin.event.LayoutEvents.LayoutClickEvent;
import com.vaadin.event.LayoutEvents.LayoutClickListener;
import com.vaadin.terminal.Sizeable;
import com.vaadin.ui.ComponentContainer;
import com.vaadin.ui.Label;
import com.vaadin.ui.Panel;
import com.vaadin.ui.VerticalLayout;
import com.vaadin.ui.VerticalSplitPanel;
import com.vaadin.ui.Window;
import com.vaadin.ui.Window.CloseEvent;
import com.vaadin.ui.Window.CloseListener;
import com.vaadin.ui.themes.Reindeer;

import org.vaadin.codeeditor.DefaultCodeEditor;
import org.vaadin.codeeditor.frontend.ace.AceFrontEnd;
import org.vaadin.peter.contextmenu.ContextMenu;
import org.vaadin.peter.contextmenu.ContextMenu.ContextMenuItem;

import serpro.mailarchiver.view.BaseApplication;
import serpro.mailarchiver.view.admin.AdminConsoleApp;
import serpro.mailarchiver.util.Logger;

@Configurable
public class scriptEditor {

    private static final Logger log = Logger.getLocalLogger();

    @PostConstruct
    private void postConstruct() {
        SubscriptionRegistry subscriptionRegistry = BaseApplication.getInstance().getDispatchContext().getSubscriptionRegistry();
        AnnotationProcessor processor = new AnnotationProcessor(subscriptionRegistry);
        processor.process(this);
    }

    private final Interpreter globalInterpreter;
    private final CallStack callstack;

    private Interpreter interpreter;

    private PrintStream interpreterOut;
    private ByteArrayOutputStream interpreterOutByteArray;
    private StringBuffer interpreterOutBuffer;

    private PrintStream interpreterErr;
    private ByteArrayOutputStream interpreterErrByteArray;
    private StringBuffer interpreterErrBuffer;

    private Window mainWindow;
    private Window window;
    private VerticalSplitPanel split;
    private EditorComponent editor;
    private OutputComponent output;

    private scriptEditor(Interpreter interpreter, CallStack callstack) {
        this.globalInterpreter = interpreter;
        this.callstack = callstack;
    }

    public static void invoke(Interpreter interpreter, CallStack callstack) {
        new scriptEditor(interpreter, callstack).init();
    }

    @Subscribe({"/mailarchiver/refresh"})
    private void refresh() {
        if(interpreterOutBuffer.length() > 0) {
            String content = interpreterOutBuffer.toString();
            interpreterOutBuffer.setLength(0);
            for(String line : content.split("\\r?\\n")) {
                output.printLn(line);
            }
        }
        if(interpreterErrBuffer.length() > 0) {
            String content = interpreterErrBuffer.toString();
            interpreterErrBuffer.setLength(0);
            for(String line : content.split("\\r?\\n")) {
                output.printErrLn(line);
            }
        }
    }

    private void init() {

        mainWindow = AdminConsoleApp.getInstance().getMainWindow();

        interpreter = new Interpreter();
        interpreter.setNameSpace(globalInterpreter.getNameSpace());
        interpreter.setStrictJava(false);

        interpreterOutByteArray = new ByteArrayOutputStream();
        interpreterOutBuffer = new StringBuffer();

        try {
            interpreterOut = new PrintStream(interpreterOutByteArray, false, "UTF-8") {
                @Override
                public void flush() {
                    super.flush();
                    if(interpreterOutByteArray.size() > 0) {
                        try {
                            String content = interpreterOutByteArray.toString("UTF-8");
                            interpreterOutByteArray.reset();
                            if(!content.isEmpty()) {
                                interpreterOutBuffer.append(content);
                            }
                        }
                        catch (UnsupportedEncodingException ex) {
                            log.error(ex);
                        }
                    }
                }
            };
        }
        catch (UnsupportedEncodingException ex) {
            log.error(ex);
        }

        interpreter.setOut(interpreterOut);

        interpreterErrByteArray = new ByteArrayOutputStream();
        interpreterErrBuffer = new StringBuffer();

        try {
            interpreterErr = new PrintStream(interpreterErrByteArray, false, "UTF-8") {
                @Override
                public void flush() {
                    super.flush();
                    if(interpreterErrByteArray.size() > 0) {
                        try {
                            String content = interpreterErrByteArray.toString("UTF-8");
                            interpreterErrByteArray.reset();
                            if(!content.isEmpty()) {
                                interpreterErrBuffer.append(content);
                            }
                        }
                        catch (UnsupportedEncodingException ex) {
                            log.error(ex);
                        }
                    }
                }
            };
        }
        catch (UnsupportedEncodingException ex) {
            log.error(ex);
        }

        interpreter.setErr(interpreterErr);

        window = new Window("MailArchiver ScriptEditor");
        window.setWidth(400, Sizeable.UNITS_PIXELS);
        window.setHeight(300, Sizeable.UNITS_PIXELS);

        split = new VerticalSplitPanel();
        split.setSizeFull();

        editor = new EditorComponent();
        editor.setStyleName("script-editor");
        editor.setMargin(false);
        editor.setSpacing(false);
        editor.setSizeFull();
        split.addComponent(editor);

        output = new OutputComponent();
        output.setSizeFull();
        split.addComponent(output);

        window.setContent(split);

        mainWindow.addWindow(window);

        window.addListener(new CloseListener() {
            @Override
            public void windowClose(CloseEvent e) {
                mainWindow.removeWindow(window);
            }
        });
    }

    private void eval(String script) {
        StringWriter sw = new StringWriter();
        try {
            Object ret = interpreter.eval(script);

            sw.append("Script result: ").append(String.valueOf(ret)).append("\n");
            print(sw);
        }
        catch(ParseException e) {
            sw.append("Parser error: ").append(e.toString()).append("\n");
            stackTrace(sw, e);
            printErr(sw);
        }
        catch(InterpreterError e) {
            sw.append("Internal error: ").append(e.toString()).append("\n");
            stackTrace(sw, e);
            printErr(sw);
        }
        catch(TargetError e) {
            sw.append("Uncaught exception: ").append(e.getTarget().toString()).append("\n");
            if(e.inNativeCode()) {
                stackTrace(sw, e.getTarget());
            }
            printErr(sw);
        }
        catch(EvalError e) {
            sw.append("Eval error: ").append(e.toString()).append("\n");
            stackTrace(sw, e);
            printErr(sw);
        }
        catch(Exception e) {
            sw.append("Unknown error: ").append(e.toString()).append("\n");
            stackTrace(sw, e);
            printErr(sw);
        }
    }

    private void print(StringWriter sw) {
        for(String line : sw.toString().split("\\r?\\n")) {
            output.printLn(line);
        }
    }

    private void printErr(StringWriter sw) {
        for(String line : sw.toString().split("\\r?\\n")) {
            output.printErrLn(line);
        }
    }

    private void stackTrace(StringWriter sw, Throwable e) {
        PrintWriter pw = new PrintWriter(sw);
        e.printStackTrace(pw);
        pw.flush();
        sw.append("\n");
    }

    private class EditorComponent extends VerticalLayout {

        private final DefaultCodeEditor codeEditor;

        private final ContextMenu editorMenu;

        private final ContextMenuItem editorEvalItem;
        private final ContextMenuItem editorClearItem;
        private final ContextMenuItem editorOpenItem;
        private final ContextMenuItem editorSaveItem;

        public EditorComponent() {

            codeEditor = new DefaultCodeEditor();
            AceFrontEnd frontEnd = new AceFrontEnd();
            codeEditor.setFrontEnd(frontEnd);
            codeEditor.setSizeFull();

            addComponent(codeEditor);

            editorMenu = new ContextMenu();

            editorEvalItem = editorMenu.addItem("Eval");
            editorClearItem = editorMenu.addItem("Clear");
            editorOpenItem = editorMenu.addItem("Open");
            editorSaveItem = editorMenu.addItem("Save");

            addListener(new LayoutClickListener() {
                @Override
                public void layoutClick(LayoutClickEvent event) {
                    if(LayoutClickEvent.BUTTON_RIGHT == event.getButton()) {
                        window.focus();
                        editorMenu.show(event.getClientX(), event.getClientY());
                    }
                }
            });

            editorMenu.addListener(new ContextMenu.ClickListener() {
                @Override
                public void contextItemClick(ContextMenu.ClickEvent event) {
                    ContextMenuItem clickedItem = event.getClickedItem();

                    if(clickedItem == editorEvalItem) {
                        final String script = (String)codeEditor.getValue();
                        new Thread() {
                            @Override
                            public void run() {
                                eval(script);
                            }
                        }
                        .start();
                    }
                    else if(clickedItem == editorClearItem) {
                        clear();
                    }
                    else if(clickedItem == editorOpenItem) {
                        open();
                    }
                    else if(clickedItem == editorSaveItem) {
                        save();
                    }
                }
            });

            editorMenu.setVisible(false);

            mainWindow.addComponent(editorMenu);
        }

        private void clear() {
            codeEditor.setValue("");
        }

        private void open() {
            System.out.println("TODO: editor open");
        }

        private void save() {
            System.out.println("TODO: editor save");
        }
    }

    private class OutputComponent extends Panel {

        private final VerticalLayout layout;

        private final ContextMenu outputMenu;

        private final ContextMenuItem outputClearItem;
        private final ContextMenuItem outputSaveItem;
        private final ContextMenuItem outputWrapItem;
        private final ContextMenuItem outputUnwrapItem;

        public OutputComponent() {

            setScrollable(true);
            setStyleName(Reindeer.PANEL_LIGHT);

            ComponentContainer container = this.getContent();
            layout = (VerticalLayout) container;
            layout.setWidth(Sizeable.SIZE_UNDEFINED, Sizeable.UNITS_PIXELS);

            outputMenu = new ContextMenu();

            outputClearItem = outputMenu.addItem("Clear");
            outputSaveItem = outputMenu.addItem("Save");
            outputWrapItem = outputMenu.addItem("Wrap");
            outputUnwrapItem = outputMenu.addItem("Unwrap");
            outputUnwrapItem.setVisible(false);

            layout.addListener(new LayoutClickListener() {
                @Override
                public void layoutClick(LayoutClickEvent event) {
                    if(LayoutClickEvent.BUTTON_RIGHT == event.getButton()) {
                        window.focus();
                        outputMenu.show(event.getClientX(), event.getClientY());
                    }
                }
            });

            outputMenu.addListener(new ContextMenu.ClickListener() {
                @Override
                public void contextItemClick(ContextMenu.ClickEvent event) {
                    ContextMenuItem clickedItem = event.getClickedItem();

                    if(clickedItem == outputClearItem) {
                        clear();
                    }
                    else if(clickedItem == outputSaveItem) {
                        save();
                    }
                    else if(clickedItem == outputWrapItem) {
                        wrap();
                    }
                    else if(clickedItem == outputUnwrapItem) {
                        unwrap();
                    }
                }
            });

            outputMenu.setVisible(false);

            mainWindow.addComponent(outputMenu);

            clear();
        }

        private void clear() {
            removeAllComponents();
        }

        private void save() {
            System.out.println("TODO: output save");
        }

        private void wrap() {
            layout.setWidth("100%");

            outputWrapItem.setVisible(false);
            outputUnwrapItem.setVisible(true);

            requestRepaint();
        }

        private void unwrap() {
            layout.setWidth(Sizeable.SIZE_UNDEFINED, Sizeable.UNITS_PIXELS);

            outputWrapItem.setVisible(true);
            outputUnwrapItem.setVisible(false);

            requestRepaint();
        }

        public void printLn(String s) {
            Label line = new Label(s, Label.CONTENT_TEXT);
            line.setStyleName("script-editor-output");
            addComponent(line);
        }

        public void printErrLn(String s) {
            Label line = new Label(s, Label.CONTENT_TEXT);
            line.setStyleName("script-editor-output-error");
            addComponent(line);
        }
    }
}