// License: GPL. For details, see LICENSE file.
package org.openstreetmap.josm.gui.layer;

import static org.openstreetmap.josm.tools.I18n.tr;
import static org.openstreetmap.josm.tools.I18n.trn;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseWheelEvent;
import java.awt.event.MouseWheelListener;
import java.io.File;
import java.io.IOException;
import java.time.format.FormatStyle;
import java.util.Collection;
import java.util.Collections;
import java.util.Objects;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.swing.Action;
import javax.swing.BorderFactory;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JEditorPane;
import javax.swing.JWindow;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.plaf.basic.BasicHTML;
import javax.swing.text.View;

import org.openstreetmap.josm.actions.AutoScaleAction;
import org.openstreetmap.josm.actions.SaveActionBase;
import org.openstreetmap.josm.data.Bounds;
import org.openstreetmap.josm.data.Data;
import org.openstreetmap.josm.data.notes.Note;
import org.openstreetmap.josm.data.notes.Note.State;
import org.openstreetmap.josm.data.notes.NoteComment;
import org.openstreetmap.josm.data.osm.NoteData;
import org.openstreetmap.josm.data.osm.NoteData.NoteDataUpdateListener;
import org.openstreetmap.josm.data.osm.visitor.BoundingXYVisitor;
import org.openstreetmap.josm.gui.MainApplication;
import org.openstreetmap.josm.gui.MapView;
import org.openstreetmap.josm.gui.dialogs.LayerListDialog;
import org.openstreetmap.josm.gui.dialogs.LayerListPopup;
import org.openstreetmap.josm.gui.io.AbstractIOTask;
import org.openstreetmap.josm.gui.io.UploadNoteLayerTask;
import org.openstreetmap.josm.gui.io.importexport.NoteExporter;
import org.openstreetmap.josm.gui.progress.ProgressMonitor;
import org.openstreetmap.josm.gui.widgets.HtmlPanel;
import org.openstreetmap.josm.io.XmlWriter;
import org.openstreetmap.josm.spi.preferences.Config;
import org.openstreetmap.josm.tools.ColorHelper;
import org.openstreetmap.josm.tools.ImageProvider;
import org.openstreetmap.josm.tools.Logging;
import org.openstreetmap.josm.tools.Utils;
import org.openstreetmap.josm.tools.date.DateUtils;

/**
 * A layer to hold Note objects.
 * @since 7522
 */
public class NoteLayer extends AbstractModifiableLayer implements MouseListener, NoteDataUpdateListener {

    /**
     * Pattern to detect end of sentences followed by another one, or a link, in western script.
     * Group 1 (capturing): period, interrogation mark, exclamation mark
     * Group non capturing: at least one horizontal or vertical whitespace
     * Group 2 (capturing): a letter (any script), or any punctuation
     */
    private static final Pattern SENTENCE_MARKS_WESTERN = Pattern.compile("([\\.\\?\\!])(?:[\\h\\v]+)([\\p{L}\\p{Punct}])");

    /**
     * Pattern to detect end of sentences followed by another one, or a link, in eastern script.
     * Group 1 (capturing): ideographic full stop
     * Group 2 (capturing): a letter (any script), or any punctuation
     */
    private static final Pattern SENTENCE_MARKS_EASTERN = Pattern.compile("(\\u3002)([\\p{L}\\p{Punct}])");

    private static final Pattern HTTP_LINK = Pattern.compile("(https?://[^\\s\\(\\)<>]+)");
    private static final Pattern HTML_LINK = Pattern.compile("<a href=\"[^\"]+\">([^<]+)</a>");
    private static final Pattern HTML_LINK_MARK = Pattern.compile("<a href=\"([^\"]+)([\\.\\?\\!])\">([^<]+)(?:[\\.\\?\\!])</a>");
    private static final Pattern SLASH = Pattern.compile("([^/])/([^/])");

    private final NoteData noteData;

    private Note displayedNote;
    private HtmlPanel displayedPanel;
    private JWindow displayedWindow;

    /**
     * Create a new note layer with a set of notes
     * @param notes A list of notes to show in this layer
     * @param name The name of the layer. Typically "Notes"
     */
    public NoteLayer(Collection<Note> notes, String name) {
        this(new NoteData(notes), name);
    }

    /**
     * Create a new note layer with a notes data
     * @param noteData Notes data
     * @param name The name of the layer. Typically "Notes"
     * @since 14101
     */
    public NoteLayer(NoteData noteData, String name) {
        super(name);
        this.noteData = Objects.requireNonNull(noteData);
        this.noteData.addNoteDataUpdateListener(this);
    }

    /** Convenience constructor that creates a layer with an empty note list */
    public NoteLayer() {
        this(Collections.<Note>emptySet(), tr("Notes"));
    }

    @Override
    public void hookUpMapView() {
        MainApplication.getMap().mapView.addMouseListener(this);
    }

    @Override
    public synchronized void destroy() {
        MainApplication.getMap().mapView.removeMouseListener(this);
        noteData.removeNoteDataUpdateListener(this);
        hideNoteWindow();
        super.destroy();
    }

    /**
     * Returns the note data store being used by this layer
     * @return noteData containing layer notes
     */
    public NoteData getNoteData() {
        return noteData;
    }

    @Override
    public boolean isModified() {
        return noteData.isModified();
    }

    @Override
    public boolean isDownloadable() {
        return true;
    }

    @Override
    public boolean isUploadable() {
        return true;
    }

    @Override
    public boolean requiresUploadToServer() {
        return isModified();
    }

    @Override
    public boolean isSavable() {
        return true;
    }

    @Override
    public boolean requiresSaveToFile() {
        return getAssociatedFile() != null && isModified();
    }

    @Override
    public void paint(Graphics2D g, MapView mv, Bounds box) {
        final int iconHeight = ImageProvider.ImageSizes.SMALLICON.getAdjustedHeight();
        final int iconWidth = ImageProvider.ImageSizes.SMALLICON.getAdjustedWidth();

        for (Note note : noteData.getNotes()) {
            Point p = mv.getPoint(note.getLatLon());

            ImageIcon icon;
            if (note.getId() < 0) {
                icon = ImageProvider.get("dialogs/notes", "note_new", ImageProvider.ImageSizes.SMALLICON);
            } else if (note.getState() == State.CLOSED) {
                icon = ImageProvider.get("dialogs/notes", "note_closed", ImageProvider.ImageSizes.SMALLICON);
            } else {
                icon = ImageProvider.get("dialogs/notes", "note_open", ImageProvider.ImageSizes.SMALLICON);
            }
            int width = icon.getIconWidth();
            int height = icon.getIconHeight();
            g.drawImage(icon.getImage(), p.x - (width / 2), p.y - height, MainApplication.getMap().mapView);
        }
        Note selectedNote = noteData.getSelectedNote();
        if (selectedNote != null) {
            paintSelectedNote(g, mv, iconHeight, iconWidth, selectedNote);
        } else {
            hideNoteWindow();
        }
    }

    private void hideNoteWindow() {
        if (displayedWindow != null) {
            displayedWindow.setVisible(false);
            for (MouseWheelListener listener : displayedWindow.getMouseWheelListeners()) {
                displayedWindow.removeMouseWheelListener(listener);
            }
            displayedWindow.dispose();
            displayedWindow = null;
            displayedPanel = null;
            displayedNote = null;
        }
    }

    private void paintSelectedNote(Graphics2D g, MapView mv, final int iconHeight, final int iconWidth, Note selectedNote) {
        Point p = mv.getPoint(selectedNote.getLatLon());

        g.setColor(ColorHelper.html2color(Config.getPref().get("color.selected")));
        g.drawRect(p.x - (iconWidth / 2), p.y - iconHeight, iconWidth - 1, iconHeight - 1);

        if (displayedNote != null && !displayedNote.equals(selectedNote)) {
            hideNoteWindow();
        }

        int xl = p.x - (iconWidth / 2) - 5;
        int xr = p.x + (iconWidth / 2) + 5;
        int yb = p.y - iconHeight - 1;
        int yt = p.y + (iconHeight / 2) + 2;
        Point pTooltip;

        String text = getNoteToolTip(selectedNote);

        if (displayedWindow == null) {
            displayedPanel = new HtmlPanel(text);
            displayedPanel.setBackground(UIManager.getColor("ToolTip.background"));
            displayedPanel.setForeground(UIManager.getColor("ToolTip.foreground"));
            displayedPanel.setFont(UIManager.getFont("ToolTip.font"));
            displayedPanel.setBorder(BorderFactory.createLineBorder(Color.black));
            displayedPanel.enableClickableHyperlinks();
            pTooltip = fixPanelSizeAndLocation(mv, text, xl, xr, yt, yb);
            displayedWindow = new JWindow(MainApplication.getMainFrame());
            displayedWindow.setAutoRequestFocus(false);
            displayedWindow.add(displayedPanel);
            // Forward mouse wheel scroll event to MapMover
            displayedWindow.addMouseWheelListener(e -> mv.getMapMover().mouseWheelMoved(
                    (MouseWheelEvent) SwingUtilities.convertMouseEvent(displayedWindow, e, mv)));
        } else {
            displayedPanel.setText(text);
            pTooltip = fixPanelSizeAndLocation(mv, text, xl, xr, yt, yb);
        }

        displayedWindow.pack();
        displayedWindow.setLocation(pTooltip);
        displayedWindow.setVisible(mv.contains(p));
        displayedNote = selectedNote;
    }

    private Point fixPanelSizeAndLocation(MapView mv, String text, int xl, int xr, int yt, int yb) {
        int leftMaxWidth = (int) (0.95 * xl);
        int rightMaxWidth = (int) (0.95 * mv.getWidth() - xr);
        int topMaxHeight = (int) (0.95 * yt);
        int bottomMaxHeight = (int) (0.95 * mv.getHeight() - yb);
        int maxWidth = Math.max(leftMaxWidth, rightMaxWidth);
        int maxHeight = Math.max(topMaxHeight, bottomMaxHeight);
        JEditorPane pane = displayedPanel.getEditorPane();
        Dimension d = pane.getPreferredSize();
        if ((d.width > maxWidth || d.height > maxHeight) && Config.getPref().getBoolean("note.text.break-on-sentence-mark", false)) {
            // To make sure long notes are displayed correctly
            displayedPanel.setText(insertLineBreaks(text));
        }
        // If still too large, enforce maximum size
        d = pane.getPreferredSize();
        if (d.width > maxWidth || d.height > maxHeight) {
            View v = (View) pane.getClientProperty(BasicHTML.propertyKey);
            if (v == null) {
                BasicHTML.updateRenderer(pane, text);
                v = (View) pane.getClientProperty(BasicHTML.propertyKey);
            }
            if (v != null) {
                v.setSize(maxWidth, 0);
                int w = (int) Math.ceil(v.getPreferredSpan(View.X_AXIS));
                int h = (int) Math.ceil(v.getPreferredSpan(View.Y_AXIS)) + 20; // see #18372 and #15550
                pane.setPreferredSize(new Dimension(w, h));
            }
        }
        d = pane.getPreferredSize();
        // place tooltip on left or right side of icon, based on its width
        Point screenloc = mv.getLocationOnScreen();
        return new Point(
                screenloc.x + (d.width > rightMaxWidth && d.width <= leftMaxWidth ? xl - d.width : xr),
                screenloc.y + (d.height > bottomMaxHeight && d.height <= topMaxHeight ? yt - d.height - 10 : yb));
    }

    /**
     * Inserts HTML line breaks ({@code <br>} at the end of each sentence mark
     * (period, interrogation mark, exclamation mark, ideographic full stop).
     * @param longText a long text that does not fit on a single line without exceeding half of the map view
     * @return text with line breaks
     */
    static String insertLineBreaks(String longText) {
        return SENTENCE_MARKS_WESTERN.matcher(SENTENCE_MARKS_EASTERN.matcher(longText).replaceAll("$1<br>$2")).replaceAll("$1<br>$2");
    }

    /**
     * Returns the HTML-formatted tooltip text for the given note.
     * @param note note to display
     * @return the HTML-formatted tooltip text for the given note
     * @since 13111
     */
    public static String getNoteToolTip(Note note) {
        StringBuilder sb = new StringBuilder("<html>");
        sb.append(tr("Note"))
          .append(' ').append(note.getId());
        for (NoteComment comment : note.getComments()) {
            String commentText = comment.getText();
            //closing a note creates an empty comment that we don't want to show
            if (!Utils.isStripEmpty(commentText)) {
                sb.append("<hr/>");
                String userName = XmlWriter.encode(comment.getUser().getName());
                if (Utils.isStripEmpty(userName)) {
                    userName = "&lt;Anonymous&gt;";
                }
                sb.append(userName)
                  .append(" on ")
                  .append(DateUtils.getDateFormatter(FormatStyle.MEDIUM).format(comment.getCommentTimestamp()))
                  .append(":<br>");
                String htmlText = XmlWriter.encode(comment.getText(), true);
                // encode method leaves us with entity instead of \n
                htmlText = htmlText.replace("&#xA;", "<br>");
                // convert URLs to proper HTML links
                htmlText = replaceLinks(htmlText);
                sb.append(htmlText);
            }
        }
        sb.append("</html>");
        String result = sb.toString();
        Logging.debug(result);
        return result;
    }

    static String replaceLinks(String htmlText) {
        String result = HTTP_LINK.matcher(htmlText).replaceAll("<a href=\"$1\">$1</a>");
        result = HTML_LINK_MARK.matcher(result).replaceAll("<a href=\"$1\">$3</a>$2");
        Matcher m1 = HTML_LINK.matcher(result);
        if (m1.find()) {
            int last = 0;
            StringBuffer sb = new StringBuffer(); // Switch to StringBuilder when switching to Java 9
            do {
                sb.append(result, last, m1.start());
                last = m1.end();
                String link = m1.group(0);
                Matcher m2 = SLASH.matcher(link).region(link.indexOf('>'), link.lastIndexOf('<'));
                while (m2.find()) {
                    m2.appendReplacement(sb, "$1/\u200b$2"); //zero width space to wrap long URLs (see #10864, #15550)
                }
                m2.appendTail(sb);
            } while (m1.find());
            result = sb.append(result, last, result.length()).toString();
        }
        return result;
    }

    @Override
    public Icon getIcon() {
        return ImageProvider.get("dialogs/notes", "note_open", ImageProvider.ImageSizes.SMALLICON);
    }

    @Override
    public String getToolTipText() {
        int size = noteData.getNotes().size();
        return trn("{0} note", "{0} notes", size, size);
    }

    @Override
    public void mergeFrom(Layer from) {
        if (from instanceof NoteLayer && this != from) {
            noteData.mergeFrom(((NoteLayer) from).noteData);
        }
    }

    @Override
    public boolean isMergable(Layer other) {
        return false;
    }

    @Override
    public void visitBoundingBox(BoundingXYVisitor v) {
        for (Note note : noteData.getNotes()) {
            v.visit(note.getLatLon());
        }
    }

    @Override
    public Object getInfoComponent() {
        StringBuilder sb = new StringBuilder();
        sb.append(tr("Notes layer"))
          .append('\n')
          .append(tr("Total notes:"))
          .append(' ')
          .append(noteData.getNotes().size())
          .append('\n')
          .append(tr("Changes need uploading?"))
          .append(' ')
          .append(isModified());
        return sb.toString();
    }

    @Override
    public Action[] getMenuEntries() {
        return new Action[]{
                LayerListDialog.getInstance().createShowHideLayerAction(),
                MainApplication.getMenu().autoScaleActions.get(AutoScaleAction.AutoScaleMode.LAYER),
                LayerListDialog.getInstance().createDeleteLayerAction(),
                new LayerListPopup.InfoAction(this),
                new LayerSaveAction(this),
                new LayerSaveAsAction(this),
        };
    }

    @Override
    public void mouseClicked(MouseEvent e) {
        if (!SwingUtilities.isLeftMouseButton(e)) {
            return;
        }
        Point clickPoint = e.getPoint();
        double snapDistance = 10;
        double minDistance = Double.MAX_VALUE;
        final int iconHeight = ImageProvider.ImageSizes.SMALLICON.getAdjustedHeight();
        Note closestNote = null;
        for (Note note : noteData.getNotes()) {
            Point notePoint = MainApplication.getMap().mapView.getPoint(note.getLatLon());
            //move the note point to the center of the icon where users are most likely to click when selecting
            notePoint.setLocation(notePoint.getX(), notePoint.getY() - iconHeight / 2d);
            double dist = clickPoint.distanceSq(notePoint);
            if (minDistance > dist && clickPoint.distance(notePoint) < snapDistance) {
                minDistance = dist;
                closestNote = note;
            }
        }
        noteData.setSelectedNote(closestNote);
    }

    @Override
    public File createAndOpenSaveFileChooser() {
        return SaveActionBase.createAndOpenSaveFileChooser(tr("Save Note file"), NoteExporter.FILE_FILTER);
    }

    @Override
    public AbstractIOTask createUploadTask(ProgressMonitor monitor) {
        return new UploadNoteLayerTask(this, monitor);
    }

    @Override
    public void mousePressed(MouseEvent e) {
        // Do nothing
    }

    @Override
    public void mouseReleased(MouseEvent e) {
        // Do nothing
    }

    @Override
    public void mouseEntered(MouseEvent e) {
        // Do nothing
    }

    @Override
    public void mouseExited(MouseEvent e) {
        // Do nothing
    }

    @Override
    public void noteDataUpdated(NoteData data) {
        invalidate();
    }

    @Override
    public void selectedNoteChanged(NoteData noteData) {
        invalidate();
    }

    @Override
    public String getChangesetSourceTag() {
        return "Notes";
    }

    @Override
    public boolean autosave(File file) throws IOException {
        new NoteExporter().exportData(file, this);
        return true;
    }

    @Override
    public Data getData() {
        return getNoteData();
    }
}