// Copyright (C) 2001-2003 Jon A. Maxwell (JAM)
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

package net.adoptopenjdk.icedteaweb.client.parts.downloadindicator;

import net.adoptopenjdk.icedteaweb.logging.Logger;
import net.adoptopenjdk.icedteaweb.logging.LoggerFactory;
import net.adoptopenjdk.icedteaweb.ui.swing.ScreenFinder;
import net.adoptopenjdk.icedteaweb.ui.swing.SwingUtils;
import net.sourceforge.jnlp.runtime.JNLPRuntime;
import net.sourceforge.jnlp.util.ImageResources;

import javax.jnlp.DownloadServiceListener;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Timer;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.HeadlessException;
import java.awt.Insets;
import java.awt.Rectangle;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import static net.adoptopenjdk.icedteaweb.i18n.Translator.R;

/**
 * Show the progress of downloads.
 *
 * @author <a href="mailto:jmaxwell@users.sourceforge.net">Jon A. Maxwell (JAM)</a> - initial author
 * @version $Revision: 1.3 $
 */
public class DefaultDownloadIndicator implements DownloadIndicator {

    private final static Logger LOG = LoggerFactory.getLogger(DefaultDownloadIndicator.class);

    // todo: rewrite this to cut down on size/complexity; smarter
    // panels (JList, renderer) understand resources instead of
    // nested panels and grid-bag mess.

    // todo: fix bug where user closes download box and it
    // never(?) reappears.

    // todo: UI for user to cancel/restart download

    // todo: this should be synchronized at some point but conflicts
    // aren't very likely.

    private static final String downloading = R("CDownloading");
    private static final String complete = R("CComplete");

    /** time to wait after completing but before window closes */
    private static final int CLOSE_DELAY = 750;

    /** the display window */
    private static JDialog dialog;
    private static final Object dialogMutex = new Object();

    /** shared constraint */
    private static final GridBagConstraints vertical;
    private static final GridBagConstraints verticalNoClean;
    private static final GridBagConstraints verticalIndent;
    static {
        vertical = new GridBagConstraints();
        vertical.gridwidth = GridBagConstraints.REMAINDER;
        vertical.weightx = 1.0;
        vertical.fill = GridBagConstraints.HORIZONTAL;
        vertical.anchor = GridBagConstraints.WEST;

        verticalNoClean = new GridBagConstraints();
        verticalNoClean.weightx = 1.0;

        verticalIndent = (GridBagConstraints) vertical.clone();
        verticalIndent.insets = new Insets(0, 10, 3, 0);
    }

    /**
     * Return a download service listener that displays the progress
     * in a shared download info window.
     *
     * @param downloadName name identifying the download to the user
     * @param resources initial urls to display (not required)
     * @return download service listener attached to this app. instance
     */
    @Override
    public DownloadServiceListener getListener(final String downloadName, final URL[] resources) {
        final FutureResult<DownloadPanel> result = new FutureResult<DownloadPanel>() {
            @Override
            public void run() {
                DownloadPanel result = new DownloadPanel(downloadName);

                synchronized (dialogMutex) {
                    if (dialog == null) {
                        dialog = createDownloadIndicatorWindow(true);
                    }

                    if (resources != null) {
                        for (URL url : resources) {
                            result.addProgressPanel(url, null);
                        }
                    }

                    dialog.getContentPane().add(result, vertical);
                    dialog.pack();
                    placeFrameToLowerRight();

                    result.addComponentListener(new ComponentAdapter() {
                        @Override
                        public void componentResized(ComponentEvent e) {
                            placeFrameToLowerRight();
                        }
                    });

                    dialog.setVisible(true);

                    setRef(result);
                }
            }
        };

        SwingUtils.invokeAndWait(result);
        return result.getRef();
    }

     private static JDialog createDownloadIndicatorWindow(boolean undecorated) throws HeadlessException {
        JDialog f = new JDialog((JFrame)null, downloading + "...");
        f.setName("DownloadIndicatorDialog");
        SwingUtils.info(f);
        f.setUndecorated(undecorated);
        f.setIconImages(ImageResources.INSTANCE.getApplicationImages());
        f.getContentPane().setLayout(new GridBagLayout());
        return f;
    }

    /**
     * This places indicator to lower right corner of active monitor.
     */
    private static void placeFrameToLowerRight() throws HeadlessException {
       Rectangle bounds = ScreenFinder.getCurrentScreenSizeWithoutBounds();
        dialog.setLocation(bounds.width+bounds.x - dialog.getWidth(),
                bounds.height+bounds.y - dialog.getHeight());
    }

    /**
     * Remove a download service listener that was obtained by
     * calling the getDownloadListener method from the shared
     * download info window.
     */
    @Override
    public void disposeListener(final DownloadServiceListener listener) {
        if (!(listener instanceof DownloadPanel))
            return;

        ActionListener hider = evt -> {
            synchronized(dialogMutex) {
                dialog.getContentPane().remove((DownloadPanel) listener);
                dialog.pack();

                if (dialog.getContentPane().getComponentCount() == 0) {
                    dialog.setVisible(false);
                    dialog.dispose();
                    dialog = null;
                }
            }
        };

        Timer timer = new Timer(CLOSE_DELAY, hider);
        timer.setRepeats(false);
        timer.start();
    }

    /**
     * Groups the url progress in a panel.
     */
    static class DownloadPanel extends JPanel implements DownloadServiceListener {
        private final DownloadPanel self;

        private enum States{
            ONE_JAR, COLLAPSED, DETAILED
        }
        
        private static final String DETAILS=R("ButShowDetails");
        private static final String HIDE_DETAILS=R("ButHideDetails");   
        /** the download name */
        private final String downloadName;
        /** Downloading part: */
        private final JLabel header = new JLabel();
        /** Show/hide detailsButton button: */
        private final JButton detailsButton;
        private static final URL magnifyGlassUrl = ClassLoader.getSystemResource("net/sourceforge/jnlp/resources/showDownloadDetails.png");
        private static final URL redCrossUrl = ClassLoader.getSystemResource("net/sourceforge/jnlp/resources/hideDownloadDetails.png");
        private static final Icon magnifyGlassIcon = new ImageIcon(magnifyGlassUrl);
        private static final Icon redCrossIcon = new ImageIcon(redCrossUrl);
        /** used  instead of detailsButton button in case of one jar*/
        private final JLabel delimiter = new JLabel("");
        /** all already created progress bars*/
        private final List<ProgressPanel> progressPanels = new ArrayList<>();
        private States state=States.ONE_JAR;
        private ProgressPanel mainProgressPanel;
        
        /** list of URLs being downloaded */
        private final List<URL> urls = new ArrayList<>();

        /** list of ProgressPanels */
        private final List<ProgressPanel> panels = new ArrayList<>();

        /**
         * Create a new download panel for with the specified download
         * name.
         */
        protected DownloadPanel(String downloadName) {
            self = this;
            setLayout(new GridBagLayout());
            this.downloadName = downloadName;
            this.add(header, verticalNoClean);
            header.setFont(header.getFont().deriveFont(Font.BOLD));
            this.add(delimiter, vertical);
            detailsButton = new JButton(magnifyGlassIcon);
            int w = magnifyGlassIcon.getIconWidth();
            int h = magnifyGlassIcon.getIconHeight();
            detailsButton.setPreferredSize(new Dimension(w + 2, h + 2));
            detailsButton.addActionListener(new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    if (state == States.DETAILED) {
                        state = States.COLLAPSED;
                        detailsButton.setToolTipText(DETAILS);
                        detailsButton.setIcon(magnifyGlassIcon);
                        for (ProgressPanel progressPanel : progressPanels) {
                            remove(progressPanel);
                        }
                        add(mainProgressPanel, verticalIndent);
                        recreateFrame(true);
                    } else {
                        state = States.DETAILED;
                        detailsButton.setToolTipText(HIDE_DETAILS);
                        detailsButton.setIcon(redCrossIcon);
                        remove(mainProgressPanel);
                        for (ProgressPanel progressPanel : progressPanels) {
                            add(progressPanel, verticalIndent);
                        }
                        recreateFrame(false);
                    }
                }

                public void recreateFrame(boolean undecorated) throws HeadlessException {
                    JDialog oldFrame = dialog;
                    dialog = createDownloadIndicatorWindow(undecorated);
                    dialog.getContentPane().add(self, vertical);
                    synchronized (dialogMutex) {
                        dialog.pack();
                        placeFrameToLowerRight();
                    }
                    dialog.setVisible(true);
                    oldFrame.dispose();
                }
            });
            setOverallPercent(0);
        }

        /**
         * Add a ProgressPanel for a URL.
         */
        protected void addProgressPanel(URL url, String version) {
            if (!urls.contains(url)) {
                ProgressPanel panel = new ProgressPanel(url, version);
                if (state != States.COLLAPSED) {
                    add(panel, verticalIndent);
                }
                progressPanels.add(panel);
                urls.add(url);
                panels.add(panel); 
                //download indicator does not know about added jars
                //When only one jar is added to download queue then its progress is
                //shown, and there is no show detail button.
                //When second one is added, then it already knows that there will
                //be two or more jars, so it swap to collapsed state in count of two.
                //no later, no sooner
                if (panels.size() == 2){
                    remove(panels.get(0));
                    remove(panels.get(1));
                    remove(delimiter);
                    add(detailsButton,vertical);
                    mainProgressPanel=new ProgressPanel();
                    add(mainProgressPanel, verticalIndent);
                    state=States.COLLAPSED;
                }
                synchronized (dialogMutex) {
                    dialog.pack();
                    placeFrameToLowerRight();
                }

            }
        }

        /**
         * Update the download progress of a url.
         */
        protected void update(final URL url, final String version,
                              final long readSoFar, final long total,
                              final int overallPercent) {
            SwingUtils.invokeLater(() -> {
                if (!urls.contains(url))
                    addProgressPanel(url, version);

                setOverallPercent(overallPercent);
                ProgressPanel panel = panels.get(urls.indexOf(url));
                panel.setProgress(readSoFar, total);
                panel.repaint();

            });
        }

        /**
         * Sets the overall percent completed.
         * should be called via invokeLater
         */
        public void setOverallPercent(int percent) {
            // don't get whole string from resource and sub in
            // values because it'll be doing a MessageFormat for
            // each update.
            String s = downloading + " " + downloadName + ": " + percent + "% " + complete + ".";
            if (JNLPRuntime.isHeadless()){
                LOG.info(s);
            }
            header.setText(s);
            Container c = header.getParent();
            //we need to adapt both panels and also dialog to new length of header text
            while (c != null) {
                c.invalidate();
                c.validate();
                if (c instanceof  Window){
                    ((Window) c).pack();
                }
                c=c.getParent();
            }
            if (mainProgressPanel != null) {
                mainProgressPanel.setProgress(percent, 100);
                mainProgressPanel.repaint();
            }
        }

        /**
         * Called when a download failed.
         */
        @Override
        public void downloadFailed(URL url, String version) {
            update(url, version, -1, -1, -1);
        }

        /**
         * Called when a download has progressed.
         */
        @Override
        public void progress(URL url, String version, long readSoFar, long total, int overallPercent) {
            update(url, version, readSoFar, total, overallPercent);
        }

        /**
         * Called when an archive is patched.
         */
        @Override
        public void upgradingArchive(URL url, String version, int patchPercent, int overallPercent) {
            update(url, version, patchPercent, 100, overallPercent);
        }

        /**
         * Called when a download is being validated.
         */
        @Override
        public void validating(URL url, String version, long entry, long total, int overallPercent) {
            update(url, version, entry, total, overallPercent);
        }

    }

    /**
     * A progress bar with the URL next to it.
     */
    static class ProgressPanel extends JPanel {
        final private JPanel bar = new JPanel();

        private long total;
        private long readSoFar;
        final private Dimension size = new Dimension(80, 15);

        ProgressPanel() {
            bar.setMinimumSize(size);
            bar.setPreferredSize(size);
            bar.setOpaque(false);

            setLayout(new GridBagLayout());

            GridBagConstraints gbc = new GridBagConstraints();
            styleGridBagConstraints(gbc);
            add(bar, gbc);
        }
        
        ProgressPanel(URL url, @SuppressWarnings("unused") String version) {
            bar.setMinimumSize(size);
            bar.setPreferredSize(size);
            bar.setOpaque(false);

            setLayout(new GridBagLayout());

            GridBagConstraints gbc = new GridBagConstraints();
            gbc.weightx = 0.0;
            gbc.fill = GridBagConstraints.NONE;
            gbc.gridwidth = GridBagConstraints.RELATIVE;
            add(bar, gbc);
            
            styleGridBagConstraints(gbc);

            JLabel location = new JLabel(" " + url.getHost() + "/" + url.getFile());
            add(location, gbc);
        }

        private void styleGridBagConstraints(GridBagConstraints gbc) {
            gbc.insets = new Insets(0, 3, 0, 0);
            gbc.weightx = 1.0;
            gbc.fill = GridBagConstraints.HORIZONTAL;
            gbc.gridwidth = GridBagConstraints.REMAINDER;
            gbc.anchor = GridBagConstraints.WEST;
        }

        public void setProgress(long readSoFar, long total) {
            this.readSoFar = readSoFar;
            this.total = total;
        }

        @Override
        public void paintComponent(Graphics g) {
            super.paintComponent(g);

            int x = bar.getX();
            int y = bar.getY();
            int h = bar.getHeight();
            int w = bar.getWidth();

            if (readSoFar <= 0 || total <= 0) {
                // make barber pole
            } else {
                double progress = (double) readSoFar / (double) total;
                int divide = (int) (w * progress);

                g.setColor(Color.white);
                g.fillRect(x, y, w, h);
                g.setColor(Color.blue);
                g.fillRect(x + 1, y + 1, divide - 1, h - 1);
            }
        }
    }

    static abstract class FutureResult<V> implements Runnable {
        private V ref = null;

        public V getRef() {
            return ref;
        }

        public void setRef(V ref) {
            this.ref = ref;
        }
    }
}
