// PathVisio,
// a tool for data visualization and analysis using Biological Pathways
// Copyright 2006-2011 BiGCaT Bioinformatics
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
package org.pathvisio.core.view;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Shape;
import java.awt.geom.AffineTransform;
import java.awt.geom.Area;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.pathvisio.core.model.ConnectorShape;
import org.pathvisio.core.model.ConnectorShape.Segment;
import org.pathvisio.core.model.ConnectorShape.WayPoint;
import org.pathvisio.core.model.GraphLink.GraphRefContainer;
import org.pathvisio.core.model.LineStyle;
import org.pathvisio.core.model.LineType;
import org.pathvisio.core.model.MLine;
import org.pathvisio.core.model.PathwayElement;
import org.pathvisio.core.model.PathwayElement.MAnchor;
import org.pathvisio.core.model.PathwayElement.MPoint;
import org.pathvisio.core.model.PathwayElementEvent;
import org.pathvisio.core.preferences.GlobalPreference;
import org.pathvisio.core.preferences.PreferenceManager;

/**
 * This class represents a Line on the pathway, or rather
 * a series of line segments that are joined together.
 *
 * It has two VPoints with a Handle. It may have zero or more anchors, each with their own Handle.
 * It has one or more segments, any segment in excess of two will get a Segment Handle.
 *
 * The actual implementation of the path is done by implementations
 * of the {@link ConnectorShape} interface.
 * @see ConnectorShape
 * @see org.pathvisio.core.model.ConnectorShapeFactory
 */
public class Line extends Graphics implements Adjustable
{
	private List<VPoint> points;

	private Map<MAnchor, VAnchor> anchors = new HashMap<MAnchor, VAnchor>();

	List<Handle> segmentHandles = new ArrayList<Handle>();

	ConnectorShape shape;

	/**
	 * Constructor for this class
	 * @param canvas - the VPathway this line will be part of
	 */
	public Line(VPathway canvas, PathwayElement o)
	{
		super(canvas, o);

		points = new ArrayList<VPoint>();
		addPoint(o.getMStart());
		addPoint(o.getMEnd());
		setAnchors();
        getConnectorShape().recalculateShape(getMLine());
//		updateSegmentHandles();
		updateCitationPosition();
	}

	private void addPoint(MPoint mp) {
		VPoint vp = canvas.newPoint(mp, this);
		points.add(vp);
		setHandleLocation(vp);
	}

	private MLine getMLine() {
		return (MLine)gdata;
	}

	public void createHandles()
	{
		createSegmentHandles();

		for (VPoint vp : points)
		{
			vp.handle = new Handle(Handle.Freedom.FREE, this, vp);
			//vp.handle.setCursorHint(Cursor.HAND_CURSOR);
			vp.handle.setAngle(1);
			setHandleLocation(vp);
		}
	}

	/**
	 * Create new segment handles
	 */
	private void createSegmentHandles()
	{
		ConnectorShape cs = getConnectorShape();
		WayPoint[] waypoints = cs.getWayPoints();

		//Destroy the old handles, just to be sure
		for(Handle h : segmentHandles) h.destroy();
		segmentHandles.clear();

		//Create the new handles
		for(int i = 0; i < waypoints.length; i++) {
			Handle h = new Handle(Handle.Freedom.FREE, this, this);
			h.setStyle(Handle.Style.SEGMENT);
			segmentHandles.add(h);
		}

		//Put the handles in the right place
		for(int i = 0; i < waypoints.length; i++) {
			Handle h = segmentHandles.get(i);
			h.setMLocation(waypoints[i].getX(), waypoints[i].getY());
		}
	}

	/**
	 * Update the segment handles, if the ConnectorShape has changed so much that
	 * the number of segment handles doesn't match the number of segments anymore,
	 * number of segments, they will be destroyed and recreated.
	 */
	private void updateSegmentHandles() {
		ConnectorShape cs = getConnectorShape();
		WayPoint[] waypoints = cs.getWayPoints();

		//Destroy and recreate the handles if the number
		//doesn't match the waypoints number
		if(waypoints.length != segmentHandles.size())
		{
			// clear and create from scratch
			createSegmentHandles();
		}
		else
		{
			// just adjust the positions
			for(int i = 0; i < waypoints.length; i++) {
				Handle h = segmentHandles.get(i);
				h.setMLocation(waypoints[i].getX(), waypoints[i].getY());
			}
		}
	}

	/**
	 * Updates the segment preferences to the new handle position
	 */
	public void adjustToHandle(Handle h, double vx, double vy) {
		WayPoint[] waypoints = getConnectorShape().getWayPoints();
		int index = segmentHandles.indexOf(h);
		if(index > -1) {
			List<MPoint> points = gdata.getMPoints();
			if(points.size() - 2 != (waypoints.length)) {
				//Recreate points from segments
				points = new ArrayList<MPoint>();
				points.add(gdata.getMStart());
				for(int i = 0; i < waypoints.length; i++) {
					MPoint p = gdata.new MPoint(waypoints[i].getX(), waypoints[i].getY());
					points.add(p);
				}
				points.add(gdata.getMEnd());
				gdata.dontFireEvents(1);
				gdata.setMPoints(points);
			}
			points.get(index + 1).moveTo(mFromV(vx), mFromV(vy));
		}
	}

	private List<Handle> getSegmentHandles() {
		return segmentHandles;
	}

	private ConnectorShape getConnectorShape() {
		return getMLine().getConnectorShape();
	}

	/**
	 * Get the connector shape translated to view coordinates
	 * allowing for Line Ending
	 * This allows the line to be drawn only upto
	 * the point where the line ending starts
	 */
	private Shape getVConnectorAdjusted() {

		//call to getLineEndingWidth
		double startGap = getGap(gdata.getStartLineType());
		double endGap = getGap(gdata.getEndLineType());

		//From the segments
		Shape s = getConnectorShape().calculateAdjustedShape(startGap, endGap);

		AffineTransform t = new AffineTransform();
		double scale = vFromM(1);
		t.setToScale(scale, scale);
		return t.createTransformedShape(s);
	}

	/**
	 * returns the gap that goes with the specified LineType
	 * If no line ending, the method returns 0
	 */
	private double getGap(LineType type) {

		double gap = 0;
		if (type == null)
		{
			gap = ShapeRegistry.getArrow ("Default").getGap();
		}
		else if (type.getName().equals ("Line"))
		{
			gap = 0;
		}
		else
		{
			gap = ShapeRegistry.getArrow (type.getName()).getGap();
		}
		return gap;

	}


	public void doDraw(Graphics2D g) 
	{
		Color c = getLineColor();
		g.setColor(c);
		setLineStyle(g);

		Shape l = getVConnectorAdjusted();

		ArrowShape[] heads = getVHeadsAdjusted();
		ArrowShape hs = heads[0];
		ArrowShape he = heads[1];

		g.draw(l);
		drawHead(g, he, c);
		drawHead(g, hs, c);
		if (isHighlighted())
		{
			Color hc = getHighlightColor();
			g.setColor(new Color (hc.getRed(), hc.getGreen(), hc.getBlue(), 128));
			g.setStroke (new BasicStroke (HIGHLIGHT_STROKE_WIDTH));
			g.draw(l);
			if (he != null) g.draw(he.getShape());
			if (hs != null) g.draw(hs.getShape());
		}

		// highlight unlinked points, after pressing Ctrl+L
		for (VPoint vp : points)
		{
			if(vp.isHighlighted()) {
				int size = 8;
				g.setColor(PreferenceManager.getCurrent().getColor(GlobalPreference.COLOR_HIGHLIGHTED));
				g.fill(new Rectangle2D.Double(
						vp.getVX() - size / 2,
						vp.getVY() - size / 2,
						size,
						size)
				);
			}
		}
	}

	/** Overridden, to unhighlight VPoints as well */
	@Override public void unhighlight()
	{
		super.unhighlight();
		for (VPoint vp : points) vp.unhighlight();
	}

	/**
	 * Be careful to prevent infinite recursion when
	 * Line.getVOutline triggers recalculation of a connector.
	 *
	 * For now, only check crossing of geneproducts and shapes.
	 */
	public Shape mayCross(Point2D point)
	{
		Shape shape = null;
		for (VPathwayElement o : canvas.getDrawingObjects())
		{
			if (o instanceof GeneProduct ||
					o instanceof Shape)
				if (o.vContains(point))
				{
					shape = o.getVOutline();
				}
		}

		return shape;
	}

	public Point2D getStartPoint() {
		return new Point2D.Double(getVStartX(), getVStartY());
	}

	public Point2D getEndPoint() {
		return new Point2D.Double(getVEndX(), getVEndY());
	}

	protected Shape calculateVOutline() {
		return getVShape(true);
	}

	/**
	 * Returns the properly sized and rotated arrowheads
	 * @return An array with two arrowheads, for the start and end respectively
	 */
	protected ArrowShape[] getVHeads() {
		Segment[] segments = getConnectorShape().getSegments();

		ArrowShape he = getVHead(
				segments[segments.length - 1].getMStart(),
				segments[segments.length - 1].getMEnd(),
				gdata.getEndLineType()
		);
		ArrowShape hs = getVHead(
				segments[0].getMEnd(),
				segments[0].getMStart(),
				gdata.getStartLineType()
		);
		return new ArrowShape[] { hs, he };
	}


	/**
	 * Returns the properly sized and rotated arrowheads which have been adjusted
	 * for Line ending thickness
	 * @return An array with two arrowheads, for the start and end respectively
	 */
	protected ArrowShape[] getVHeadsAdjusted() {
		Segment[] segments = getConnectorShape().getSegments();

		//last segment in the Connector Shape
		double lineEndingWidth = getGap(gdata.getEndLineType());
		Point2D adjustedSegmentEnd = segments[segments.length - 1].calculateNewEndPoint(lineEndingWidth);
		ArrowShape he = getVHead(
				segments[segments.length - 1].getMStart(),
				adjustedSegmentEnd,
				gdata.getEndLineType()
		);

		//first segment in the connector shape
		double lineStartingWidth = getGap(gdata.getStartLineType());
		Point2D adjustedSegmentStart = segments[0].calculateNewStartPoint(lineStartingWidth);
		ArrowShape hs = getVHead(
				segments[0].getMEnd(),
				adjustedSegmentStart,
				gdata.getStartLineType()
		);
		return new ArrowShape[] { hs, he };
	}

	protected Shape getVShape(boolean rotate) {
		Shape l = getVConnectorAdjusted();

		ArrowShape[] heads = getVHeadsAdjusted();
		ArrowShape hs = heads[0];
		ArrowShape he = heads[1];
		
		float thickness = (float) vFromM(gdata.getLineThickness());
		if (gdata.getLineStyle() == LineStyle.DOUBLE) thickness *= 4;
		BasicStroke bs = new BasicStroke (thickness);
		
		Area total = new Area(bs.createStrokedShape(l));
		if (hs != null) total.add (new Area (bs.createStrokedShape(hs.getShape())));
		if (he != null) total.add (new Area (bs.createStrokedShape(he.getShape())));
		
		return total;
	}

	private void setAnchors() {
		//Check for new anchors
		List<MAnchor> manchors = gdata.getMAnchors();
		for(MAnchor ma : manchors) {
			if(!anchors.containsKey(ma)) {
				anchors.put(ma, new VAnchor(ma, this));
			}
		}
		//Check for deleted anchors
		for(MAnchor ma : anchors.keySet()) {
			if(!manchors.contains(ma)) {
				anchors.get(ma).destroy();
			}
		}
	}

	protected Collection<VAnchor> getVAnchors() {
		return anchors.values();
	}

	public void markDirty() {
		super.markDirty();
		for(VAnchor va : anchors.values()) {
			va.markDirty();
		}
	}

	void removeVAnchor(VAnchor va) {
		anchors.remove(va.getMAnchor());
		gdata.removeMAnchor(va.getMAnchor());
	}

	private void updateAnchorPositions() {
		for(VAnchor va : anchors.values()) {
			va.updatePosition();
		}
	}

	private void updateCitationPosition()
	{
		if (getCitation() == null) return;
		Point2D p = getConnectorShape().fromLineCoordinate(0.7);
		p.setLocation(p.getX() - 5, p.getY());
		Point2D r = gdata.toRelativeCoordinate(p);
		getCitation().setRPosition(r);
	}

	protected void swapPoint(VPoint pOld, VPoint pNew)
	{
		int i = points.indexOf(pOld);
		if(i > -1) {
			points.remove(pOld);
			points.add(i, pNew);
		}
	}

	protected void drawHead(Graphics2D g, ArrowShape head, Color c)
	{
		if(head != null)
		{
			// reset stroked line to solid, but use given thickness
			g.setStroke(new BasicStroke((float) vFromM(gdata.getLineThickness())));
			switch (head.getFillType())
			{
			case OPEN:
				g.setPaint (Color.WHITE);
				g.fill (head.getShape());
				g.setColor (c);
				g.draw (head.getShape());
				break;
			case CLOSED:
				g.setPaint (c);
				g.fill (head.getShape());
				break;
			case WIRE:
				g.setColor (c);
				g.draw (head.getShape());
				break;
			default:
				assert (false);
			}
		}
	}

	/**
	   Will return the arrowhead suitable for an arrow pointing from
	   p1 to p2 (so the tip of the arrowhead will be at p2).
	   @param mP1	The start point in model coordinates
	   @param mP2	The end point in model coordinates
	   @return The ArrowShape in view coordinates
	 */
	protected ArrowShape getVHead(Point2D mP1, Point2D mP2, LineType type)
	{
		double xs = vFromM(mP1.getX());
		double ys = vFromM(mP1.getY());
		double xe = vFromM(mP2.getX());
		double ye = vFromM(mP2.getY());

		ArrowShape h;
		if (type == null)
		{
			h = ShapeRegistry.getArrow ("Default");
		}
		else if (type.getName().equals ("Line"))
		{
			h = null;
		}
		else
		{
			h = ShapeRegistry.getArrow (type.getName());
		}

		if(h != null)
		{
			AffineTransform f = new AffineTransform();
			double scaleFactor = vFromM (1.0 + 0.3 * gdata.getLineThickness());
			f.rotate(Math.atan2 (ye - ys, xe - xs), xe, ye);
			f.translate (xe, ye);
			f.scale (scaleFactor, scaleFactor);
			Shape sh = f.createTransformedShape(h.getShape());
			h = new ArrowShape (sh, h.getFillType());
		}
		return h;
	}

	/**
	 * Sets the line start and end to the coordinates specified
	 * <DL><B>Parameters</B>
	 * <DD>Double x1	- new startx
	 * <DD>Double y1	- new starty
	 * <DD>Double x2	- new endx
	 * <DD>Double y2	- new endy
	 */
	private void setVLine(double vx1, double vy1, double vx2, double vy2)
	{
		getStart().setVLocation(vx1, vy1);
		getEnd().setVLocation(vx2, vy2);
	}

	protected void setVScaleRectangle(Rectangle2D r) {
		setVLine(r.getX(), r.getY(), r.getX() + r.getWidth(), r.getY() + r.getHeight());
	}

	public List<VPoint> getPoints() { return points; }

	public VPoint getStart() {
		return points.get(0);
	}

	public VPoint getEnd() {
		return points.get(points.size() - 1);
	}

	public double getVCenterX()
	{
		return vFromM(gdata.getMCenterX());
	}

	public double getVCenterY()
	{
		return vFromM(gdata.getMCenterY());
	}

	public double getVLeft()
	{
		return vFromM(gdata.getMLeft());
	}

	public double getVWidth()
	{
		return vFromM(gdata.getMWidth());
	}

	public double getVHeight()
	{
		return vFromM(gdata.getMHeight());
	}

	public double getVTop()
	{
		return vFromM(gdata.getMTop());
	}

	protected void vMoveWayPointsBy(double vdx, double vdy) {
		List<MPoint> mps = gdata.getMPoints();
		for(int i = 1; i < mps.size() - 1; i++) {
			mps.get(i).moveBy(mFromV(vdx), mFromV(vdy));
		}
	}

    protected void vRecalculatePoints(double vdx, double vdy)
    {
        for(VPoint p : points) {
            p.setVLocation(p.getVX() + canvas.mFromV(vdx), p.getVY() + canvas.mFromV(vdy));
		}
    }

    protected void vMoveBy(double vdx, double vdy)
	{
		// move MPoints directly, not every MPoint is represented
		// by a VPoint but we want to move them all.
		for(MPoint p : gdata.getMPoints())
		{
			p.moveBy(canvas.mFromV(vdx), canvas.mFromV(vdy));
		}
		//Redraw graphRefs
		for(GraphRefContainer ref : gdata.getReferences()) {
			if(ref instanceof MPoint) {
				VPoint vp = canvas.getPoint((MPoint)ref);
				if(vp != null) {
					vp.getLine().recalculateConnector();
				}
			}
		}
	}

	private void setHandleLocation(VPoint vp)
	{
		if (vp.handle == null) return;
		MPoint mp = vp.getMPoint();
		vp.handle.setMLocation(mp.getX(), mp.getY());
	}

	public void recalculateConnector() {
		getConnectorShape().recalculateShape(getMLine());
		updateAnchorPositions();
		updateCitationPosition();
		for (VPoint vp : points) setHandleLocation(vp);
		markDirty();
	}

	public void gmmlObjectModified(PathwayElementEvent e) {
		getConnectorShape().recalculateShape(getMLine());

		WayPoint[] wps = getConnectorShape().getWayPoints();
		List<MPoint> mps = gdata.getMPoints();
		if(wps.length == mps.size() - 2 && getConnectorShape().hasValidWaypoints(getMLine())) {
			getMLine().adjustWayPointPreferences(wps);
		} else {
			getMLine().resetWayPointPreferences();
		}

		updateSegmentHandles();
		markDirty();
		for(VPoint p : points) {
			setHandleLocation(p);
		}
		if(gdata.getMAnchors().size() != anchors.size()) {
			setAnchors();
		}
		updateAnchorPositions();
		updateCitationPosition();
	}

	protected void destroyHandles() {
		//Point handles will be destroyed by VPoints

		for(Handle h : getSegmentHandles()) {
			h.destroy();
		}
		for(VPoint p : points) {
			if (p.handle != null)
				p.handle.destroy();
		}
	}

	protected void destroy() {
		super.destroy();

		for(MPoint p : gdata.getMPoints()) {
			canvas.pointsMtoV.remove(p);
		}
		List<VAnchor> remove = new ArrayList<VAnchor>(anchors.values());
		for(VAnchor a : remove) {
			a.destroy();
		}
	}

	/**
	 * Returns the x-coordinate of the start point of this line, adjusted to the
	 * current zoom factor
	 * @return
	 */
	protected double getVStartX() { return (int)(vFromM(gdata.getMStartX())); }

	/**
	 * Returns the y-coordinate of the start point of this line, adjusted to the
	 * current zoom factor
	 * @return
	 */
	protected double getVStartY() { return (int)(vFromM(gdata.getMStartY())); }

	/**
	 * Returns the x-coordinate of the end point of this line, adjusted to the
	 * current zoom factor
	 * @return
	 */
	protected double getVEndX() { return (int)(vFromM(gdata.getMEndX())); }

	/**
	 * Returns the y-coordinate of the end point of this line, adjusted to the
	 * current zoom factor
	 * @return
	 */
	protected double getVEndY() { return (int)(vFromM(gdata.getMEndY())); }

	/**
	 * Translate a line coordinate (1-dimensional) to
	 * a view coordinate
	 * @param l The line coordinate
	 */
	public Point2D vFromL(double l) {
		Point2D m = getConnectorShape().fromLineCoordinate(l);
		return new Point2D.Double(vFromM(m.getX()), vFromM(m.getY()));
	}

	/**
	 * Translate a view coordinate (2-dimensional) to
	 * a line coordinate (1-dimensional)
	 */
	public double lFromV(Point2D v) {
		Point2D m = new Point2D.Double(mFromV(v.getX()), mFromV(v.getY()));
		return getConnectorShape().toLineCoordinate(m);
	}

	/**
	 * Get the segment on which the given line coordinate
	 * lies
	 */
	public Segment getSegment(double lc) {
		Segment[] segments = getConnectorShape().getSegments();
		double length = 0;
		for(Segment s : segments) {
			length += s.getMLength();
		}
		double end = 0;
		for(Segment s : segments) {
			end += s.getMLength();
			if(lc <= end) {
				return s;
			}
		}
		return segments[segments.length];
	}
}