/* Communication module for Android terminals.  -*- c-file-style: "GNU" -*-

Copyright (C) 2023-2024 Free Software Foundation, Inc.

This file is part of GNU Emacs.

GNU Emacs is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or (at
your option) any later version.

GNU Emacs 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */

package org.gnu.emacs;

import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;

public final class EmacsDrawLine
{
  public static void
  perform (EmacsDrawable drawable, EmacsGC gc,
	   int x, int y, int x2, int y2)
  {
    Canvas canvas;
    Paint paint;
    int x0, x1, y0, y1;

    /* TODO implement stippling.  */
    if (gc.fill_style == EmacsGC.GC_FILL_OPAQUE_STIPPLED)
      return;

    /* Calculate the leftmost and rightmost points.  */

    x0 = Math.min (x, x2 + 1);
    x1 = Math.max (x, x2 + 1);
    y0 = Math.min (y, y2 + 1);
    y1 = Math.max (y, y2 + 1);

    /* And the clip rectangle.  */

    paint = gc.gcPaint;
    canvas = drawable.lockCanvas (gc);

    if (canvas == null)
      return;

    paint.setStyle (Paint.Style.FILL);

    /* Since drawLine has PostScript style behavior, adjust the
       coordinates appropriately.

       The left most pixel of a straight line is always partially
       filled.  Patch it in manually.  */

    if (gc.clip_mask == null)
      {
	canvas.drawLine ((float) x + 0.5f, (float) y + 0.5f,
			 (float) x2 + 0.5f, (float) y2 + 0.5f,
			 paint);

	if (x2 > x)
	  canvas.drawRect (new Rect (x, y, x + 1, y + 1), paint);
      }

    /* DrawLine with clip mask not implemented; it is not used by
       Emacs.  */
    drawable.damageRect (x0, y0, x1, y1);
  }
}