//
//  GTMNSBezierPath+RoundRect.h
//
//  Category for adding utility functions for creating
//  round rectangles.
//
//  Copyright 2006-2008 Google Inc.
//
//  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.
//

#import "GTMNSBezierPath+RoundRect.h"

@implementation NSBezierPath (GTMBezierPathRoundRectAdditions)


+ (NSBezierPath *)gtm_bezierPathWithRoundRect:(NSRect)rect
                                 cornerRadius:(CGFloat)radius {
  NSBezierPath *bezier = [NSBezierPath bezierPath];
  [bezier gtm_appendBezierPathWithRoundRect:rect cornerRadius:radius];
  return bezier;
}

+ (NSBezierPath *)gtm_bezierPathWithRoundRect:(NSRect)rect
                          topLeftCornerRadius:(CGFloat)radiusTL
                         topRightCornerRadius:(CGFloat)radiusTR
                       bottomLeftCornerRadius:(CGFloat)radiusBL
                      bottomRightCornerRadius:(CGFloat)radiusBR {
  NSBezierPath *bezier = [NSBezierPath bezierPath];
  [bezier gtm_appendBezierPathWithRoundRect:rect
                        topLeftCornerRadius:radiusTL
                       topRightCornerRadius:radiusTR
                     bottomLeftCornerRadius:radiusBL
                    bottomRightCornerRadius:radiusBR];
  return bezier;
}

- (void)gtm_appendBezierPathWithRoundRect:(NSRect)rect
                             cornerRadius:(CGFloat)radius {
  if (radius > 0.0) {
    // Clamp radius to be no larger than half the rect's width or height.
    radius = MIN(radius, 0.5 * MIN(rect.size.width, rect.size.height));

    [self gtm_appendBezierPathWithRoundRect:rect
                        topLeftCornerRadius:radius
                       topRightCornerRadius:radius
                     bottomLeftCornerRadius:radius
                    bottomRightCornerRadius:radius];
  } else {
    // When radius <= 0.0, use plain rectangle.
    [self appendBezierPathWithRect:rect];
  }
}

- (void)gtm_appendBezierPathWithRoundRect:(NSRect)rect
                      topLeftCornerRadius:(CGFloat)radiusTL
                     topRightCornerRadius:(CGFloat)radiusTR
                   bottomLeftCornerRadius:(CGFloat)radiusBL
                  bottomRightCornerRadius:(CGFloat)radiusBR {
  // Clamp radii to be at least zero. I'd like to clamp both TL+TR and BL+BR to
  // be less than the width and TL+BL and TR+BR to be less than the height, but
  // what to do if they're not? Do we scale them both evenly?
  radiusTL = MAX(0, radiusTL);
  radiusTR = MAX(0, radiusTR);
  radiusBL = MAX(0, radiusBL);
  radiusBR = MAX(0, radiusBR);

  if (!NSIsEmptyRect(rect)) {
    NSPoint topLeft = NSMakePoint(NSMinX(rect), NSMaxY(rect));
    NSPoint topRight = NSMakePoint(NSMaxX(rect), NSMaxY(rect));
    NSPoint bottomRight = NSMakePoint(NSMaxX(rect), NSMinY(rect));

    [self moveToPoint:NSMakePoint(NSMidX(rect), NSMaxY(rect))];
    [self appendBezierPathWithArcFromPoint:topLeft
                                   toPoint:rect.origin
                                    radius:radiusTL];
    [self appendBezierPathWithArcFromPoint:rect.origin
                                   toPoint:bottomRight
                                    radius:radiusBL];
    [self appendBezierPathWithArcFromPoint:bottomRight
                                   toPoint:topRight
                                    radius:radiusBR];
    [self appendBezierPathWithArcFromPoint:topRight
                                   toPoint:topLeft
                                    radius:radiusTR];
    [self closePath];
  }
}


@end