/*******************************************************************************
 * Copyright (c) 2019 Association for Decentralized Information Management
 * in Industry THTH ry.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Semantum Oy - initial API and implementation
 *******************************************************************************/
package org.simantics.platform.ui;

import java.io.IOException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.console.ConsolePlugin;
import org.eclipse.ui.console.IConsole;
import org.eclipse.ui.console.MessageConsole;
import org.eclipse.ui.console.MessageConsoleStream;

public class SimanticsConsole extends MessageConsole {

    // We don't want to constantly lose data, but this is still only half MB
    private static int HIGH_WATERMARK = 2<<18;
    // 75%
    private static int LOW_WATERMARK = 3 * (HIGH_WATERMARK>>2);

    private ExecutorService executor = Executors.newSingleThreadExecutor();

    private Color black;
    private Color red;
    private Color green;
    private Color yellow;
    private Color blue;
    private Color magenta;
    private Color cyan;
    private Color white;

    private MessageConsoleStream stream;

    public SimanticsConsole() {
        super("Simantics Console", "Simantics Console", null, true);
    }

    @Override
    protected void init() {
        Display d = Display.getDefault();

        black = tuneColor(d, SWT.COLOR_BLACK);
        red = tuneColor(d, SWT.COLOR_RED);
        green = tuneColor(d, SWT.COLOR_GREEN);
        yellow = tuneColor(d, SWT.COLOR_YELLOW);
        blue = tuneColor(d, SWT.COLOR_BLUE);
        magenta = tuneColor(d, SWT.COLOR_MAGENTA);
        cyan = tuneColor(d, SWT.COLOR_CYAN);
        white = tuneColor(d, SWT.COLOR_WHITE);

        setBackground(black);
        stream = newMessageStream();
        stream.setFontStyle(SWT.NORMAL);
        stream.setColor(white);

        setWaterMarks(LOW_WATERMARK, HIGH_WATERMARK);

    }

    @Override
    protected void dispose() {
        super.dispose();
        executor.shutdown();
        try {
            stream.close();
        } catch (IOException e) {
            // nothing to do
        }

        black.dispose();
        red.dispose();
        green.dispose();
        green.dispose();
        yellow.dispose();
        blue.dispose();
        magenta.dispose();
        cyan.dispose();
        white.dispose();
    }

    private Color tuneColor(Display d, int color) {
        Color c = d.getSystemColor(color);
        return new Color(d, (int)(c.getRed() * 0.75), (int)(c.getGreen() * 0.75), (int)(c.getBlue() * 0.75));
    }

    public static SimanticsConsole show() {

        if(!Thread.currentThread().equals(Display.getDefault().getThread())) {
            Display.getDefault().asyncExec(() -> show());
            return null;
        }

        for (IConsole c : ConsolePlugin.getDefault().getConsoleManager().getConsoles()) {
            if (c instanceof SimanticsConsole) {
                SimanticsConsole sc = (SimanticsConsole) c;
                sc.activate();
                return sc;
            }
        }

        SimanticsConsole sc = new SimanticsConsole();
        ConsolePlugin.getDefault().getConsoleManager().addConsoles(new SimanticsConsole[] {sc});
        sc.activate();
        return sc;

    }

    public static SimanticsConsole findConsole() {

        for (IConsole c : ConsolePlugin.getDefault().getConsoleManager().getConsoles()) {
            if (c instanceof SimanticsConsole) {
                return (SimanticsConsole) c;
            }
        }

        SimanticsConsole sc = new SimanticsConsole();
        ConsolePlugin.getDefault().getConsoleManager().addConsoles(new SimanticsConsole[] {sc});
        return sc;

    }

    public void write(String data) {
        executor.submit(() -> {
            Pattern p = Pattern.compile("(\\x1b\\[(?<cmd>.*?(m)))");
            Matcher m = p.matcher(data);
            int pos = 0;
            while (m.find()) {
                if (m.start() > pos) {
                    stream.print(data.substring(pos, m.start()));
                }
                pos = m.end();

                String cmd = m.group("cmd");
                if (cmd.endsWith("m")) {
                    // Stream style can be set only in UI thread
                    Display.getDefault().syncExec(() -> {
                        int fontStyle = stream.getFontStyle();
                        Color color = stream.getColor();
                        try {
                            stream.close();
                        } catch (IOException e) {
                            // nothing to do
                        }
                        stream = newMessageStream();

                        String attributes[] = cmd.substring(0, cmd.length() - 1).split(";");
                        for (String attribute : attributes) {
                            switch (Integer.parseInt(attribute)) {
                                case 0: fontStyle = SWT.NORMAL; break;
                                case 1: fontStyle = SWT.BOLD; break;
                                case 4: break; // underline
                                case 5: break; // blink
                                case 7: break; // reverse video
                                case 8: break; // nondisplayed
                                case 30: color = black; break;
                                case 31: color = red; break;
                                case 32: color = green; break;
                                case 33: color = yellow; break;
                                case 34: color = blue; break;
                                case 35: color = magenta; break;
                                case 36: color = cyan; break;
                                case 37: color = white; break;
                                // background colors not supported
                                default:break;
                            }
                        }
                        stream.setColor(color);
                        stream.setFontStyle(fontStyle);
                    });
                }
            }
            if (pos < data.length()) {
                stream.print(data.substring(pos));
            }
            stream.println();
        });
    }
}