package jmri.jmrit.display;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Point;
import java.util.ArrayList;

import javax.annotation.Nonnull;

import jmri.Sensor;
import jmri.jmrit.display.controlPanelEditor.shape.LocoLabel;
import jmri.jmrit.logix.OBlock;

/**
 * A utility class replacing common methods formerly implementing the
 * IndicatorTrack interface.
 *
 * @author Pete Cressman Copyright (c) 2012
 */
public class IndicatorTrackPaths {

    protected ArrayList<String> _paths;      // list of paths that this icon displays
    private boolean _showTrain;         // this track icon should display _loco when occupied
    private LocoLabel _loco = null;

    protected IndicatorTrackPaths() {
    }

    protected IndicatorTrackPaths deepClone() {
        IndicatorTrackPaths p = new IndicatorTrackPaths();
        if (_paths != null) {
            p._paths = new ArrayList<>();
            for (int i = 0; i < _paths.size(); i++) {
                p._paths.add(_paths.get(i));
            }
        }
        p._showTrain = _showTrain;
        return p;
    }

    protected ArrayList<String> getPaths() {
        return _paths;
    }

    protected void setPaths(ArrayList<String> paths) {
        _paths = paths;
    }

    protected void addPath(String path) {
        if (_paths == null) {
            _paths = new ArrayList<>();
        }
        if (path != null && path.length() > 0 && !_paths.contains(path.trim() )) {
            _paths.add(path.trim());
        }
        log.debug("addPath \"{}\" #paths= {}", path, _paths.size());
    }

    protected void removePath(String path) {
        if ( _paths != null && path != null && path.length() > 0 ) {
            _paths.remove(path.trim());
        }
    }

    protected void setShowTrain(boolean set) {
        _showTrain = set;
    }

    protected boolean showTrain() {
        return _showTrain;
    }

    protected synchronized String getStatus(OBlock block, int state) {
        String pathName = block.getAllocatedPathName();
        String status;
        removeLocoIcon();
        if ((state & OBlock.TRACK_ERROR) != 0) {
            status = "ErrorTrack";
        } else if ((state & OBlock.OUT_OF_SERVICE) != 0) {
            status = "DontUseTrack";
        } else if ((state & OBlock.ALLOCATED) != 0) {
            if (_paths != null && _paths.contains(pathName)) {
                if ((state & OBlock.RUNNING) != 0) {
                    status = "PositionTrack";   //occupied by train on a warrant
                } else if ((state & OBlock.OCCUPIED) != 0) {
                    status = "OccupiedTrack";   // occupied by rouge train
                } else {
                    status = "AllocatedTrack";
                }
            } else {
                status = "ClearTrack";     // icon not on path
            }
        } else if ((state & OBlock.OCCUPIED) != 0) {
            status = "OccupiedTrack";
//        } else if ((state & Sensor.UNKNOWN)!=0) {
//            status = "DontUseTrack";
        } else {
            status = "ClearTrack";
        }
        return status;
    }

    public void removeLocoIcon() {
        if (_loco != null) {
            _loco.remove();
            _loco = null;
        }
    }

    /**
     * @param block OBlock occupied by train
     * @param pt    position of track icon
     * @param size  size of track icon
     * @param ed    editor
     * LocoLabel ctor causes editor to draw a graphic. Must be done on GUI
     * Called from IndicatorTrackIcon.setStatus and IndicatorTurnoutIcon.setStatus
     * Each wraps this method with ThreadingUtil.runOnLayoutEventually, so there is
     * a time lag for when track icon changes and display of the change.
     */
    @SuppressWarnings("deprecation")    // The method getId() from the type Thread is deprecated since version 19
                                        // The replacement Thread.threadId() isn't available before version 19
    @jmri.InvokeOnLayoutThread
    protected synchronized void setLocoIcon(@Nonnull OBlock block, Point pt, Dimension size, Editor ed) {
        if (!_showTrain) {
            removeLocoIcon();
            return;
        }
        String trainName = (String) block.getValue();
        if (trainName == null || trainName.isEmpty()) {
            removeLocoIcon();
            return;
        }
        if ((block.getState() & (OBlock.OCCUPIED | OBlock.RUNNING)) == 0) {
            // during delay of runOnLayoutEventually, state has changed
            // don't paint loco icon 
            return;
        }
        // ed may have been disposed before this runOnGUIEventually callback fires
        if (_loco != null || pt == null || !ed.isDisplayable()) {
            return;
        }
        trainName = trainName.trim();
        try {
            _loco = new LocoLabel(ed);
        } catch (Exception e) {
            jmri.jmrit.logix.Warrant w = block.getWarrant();
            log.error("Exception in setLocoIcon() in thread {} {} for block \"{}\", train \"{}\" \"{}\". state= {} at pt({}, {})",
                    Thread.currentThread().getName(), Thread.currentThread().getId(), block.getDisplayName(), trainName,
                    (w!=null? w.getDisplayName(): "no warrant"), block.getState(), pt.x, pt.y, e);
            return;
        }
        Font font = block.getMarkerFont();
        if (font == null) {
            font = ed.getFont();
        }
        int width = ed.getFontMetrics(font).stringWidth(trainName);
        int height = ed.getFontMetrics(ed.getFont()).getHeight();   // limit height to locoIcon height
        _loco.setLineWidth(1);
        _loco.setLineColor(Color.BLACK);
        _loco.setFillColor(block.getMarkerBackground());
        _loco.setBlock(block);
        _loco.setWidth(width + height / 2);
        _loco.setHeight(height + 2);
        _loco.setCornerRadius(height);
        _loco.setDisplayLevel(Editor.MARKERS);
        _loco.updateSize();
        pt.x += (size.width - _loco.maxWidth()) / 2;
        pt.y += (size.height - _loco.maxHeight()) / 2;
        _loco.setLocation(pt);
        try {
            ed.putItem(_loco);
        } catch (Positionable.DuplicateIdException e) {
            // This should never happen
            log.error("Editor.putItem() with null id has thrown DuplicateIdException", e);
        }
    }

    /*
     * Return track name for known state of occupancy sensor
     */
    protected String getStatus(int state) {
        String status;
        switch (state) {
            case Sensor.ACTIVE:
                status = "OccupiedTrack";
                break;
            case Sensor.INACTIVE:
                status = "ClearTrack";
                break;
            case Sensor.UNKNOWN:
                status = "DontUseTrack";
                break;
            default:
                status = "ErrorTrack";
                break;
        }
        return status;
    }

    private static final org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger(IndicatorTrackPaths.class);

}