Swiftgram/examples/Kittens/Sample/KittenNode.m

/* This file provided by Facebook is for non-commercial testing and evaluation
 * purposes only.  Facebook reserves all rights not expressly granted.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * FACEBOOK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#import "KittenNode.h"

#import <AsyncDisplayKit/ASDisplayNode+Subclasses.h>

static const CGFloat kImageSize = 80.0f;
static const CGFloat kOuterPadding = 16.0f;
static const CGFloat kInnerPadding = 10.0f;


@interface KittenNode ()
{
  CGSize _kittenSize;

  ASImageNode *_imageNode;
  ASTextNode *_textNode;
  ASDisplayNode *_divider;
}

@end


@implementation KittenNode

// lorem ipsum text courtesy http://kittyipsum.com/ <3
+ (NSArray *)placeholders
{
  static NSArray *placeholders = nil;

  static dispatch_once_t once;
  dispatch_once(&once, ^{
    placeholders = @[
                     @"Kitty ipsum dolor sit amet, purr sleep on your face lay down in your way biting, sniff tincidunt a etiam fluffy fur judging you stuck in a tree kittens.",
                     @"Lick tincidunt a biting eat the grass, egestas enim ut lick leap puking climb the curtains lick.",
                     @"Lick quis nunc toss the mousie vel, tortor pellentesque sunbathe orci turpis non tail flick suscipit sleep in the sink.",
                     @"Orci turpis litter box et stuck in a tree, egestas ac tempus et aliquam elit.",
                     @"Hairball iaculis dolor dolor neque, nibh adipiscing vehicula egestas dolor aliquam.",
                     @"Sunbathe fluffy fur tortor faucibus pharetra jump, enim jump on the table I don't like that food catnip toss the mousie scratched.",
                     @"Quis nunc nam sleep in the sink quis nunc purr faucibus, chase the red dot consectetur bat sagittis.",
                     @"Lick tail flick jump on the table stretching purr amet, rhoncus scratched jump on the table run.",
                     @"Suspendisse aliquam vulputate feed me sleep on your keyboard, rip the couch faucibus sleep on your keyboard tristique give me fish dolor.",
                     @"Rip the couch hiss attack your ankles biting pellentesque puking, enim suspendisse enim mauris a.",
                     @"Sollicitudin iaculis vestibulum toss the mousie biting attack your ankles, puking nunc jump adipiscing in viverra.",
                     @"Nam zzz amet neque, bat tincidunt a iaculis sniff hiss bibendum leap nibh.",
                     @"Chase the red dot enim puking chuf, tristique et egestas sniff sollicitudin pharetra enim ut mauris a.",
                     @"Sagittis scratched et lick, hairball leap attack adipiscing catnip tail flick iaculis lick.",
                     @"Neque neque sleep in the sink neque sleep on your face, climb the curtains chuf tail flick sniff tortor non.",
                     @"Ac etiam kittens claw toss the mousie jump, pellentesque rhoncus litter box give me fish adipiscing mauris a.",
                     @"Pharetra egestas sunbathe faucibus ac fluffy fur, hiss feed me give me fish accumsan.",
                     @"Tortor leap tristique accumsan rutrum sleep in the sink, amet sollicitudin adipiscing dolor chase the red dot.",
                     @"Knock over the lamp pharetra vehicula sleep on your face rhoncus, jump elit cras nec quis quis nunc nam.",
                     @"Sollicitudin feed me et ac in viverra catnip, nunc eat I don't like that food iaculis give me fish.",
                     ];
  });

  return placeholders;
}

- (instancetype)initWithKittenOfSize:(CGSize)size
{
  if (!(self = [super init]))
    return nil;

  _kittenSize = size;

  // kitten image, with a purple background colour serving as placeholder
  _imageNode = [[ASImageNode alloc] init];
  _imageNode.backgroundColor = [UIColor purpleColor];
  [self addSubnode:_imageNode];

  // lorem ipsum text, plus some nice styling
  _textNode = [[ASTextNode alloc] init];
  _textNode.attributedString = [[NSAttributedString alloc] initWithString:[self kittyIpsum]
                                                               attributes:[self textStyle]];
  [self addSubnode:_textNode];

  // hairline cell separator
  _divider = [[ASDisplayNode alloc] init];
  _divider.backgroundColor = [UIColor lightGrayColor];
  [self addSubnode:_divider];

  // download a placekitten of the requested size
  [self fetchKitten];

  return self;
}

- (NSString *)kittyIpsum
{
  NSArray *placeholders = [KittenNode placeholders];
  u_int32_t ipsumCount = (u_int32_t)[placeholders count];
  u_int32_t location = arc4random_uniform(ipsumCount);
  u_int32_t length = arc4random_uniform(ipsumCount - location);

  NSMutableString *string = [placeholders[location] mutableCopy];
  for (u_int32_t i = location + 1; i < location + length; i++) {
    [string appendString:(i % 2 == 0) ? @"\n" : @"  "];
    [string appendString:placeholders[i]];
  }

  return string;
}

- (NSDictionary *)textStyle
{
  UIFont *font = [UIFont fontWithName:@"HelveticaNeue" size:12.0f];

  NSMutableParagraphStyle *style = [[NSParagraphStyle defaultParagraphStyle] mutableCopy];
  style.paragraphSpacing = 0.5 * font.lineHeight;
  style.hyphenationFactor = 1.0;

  return @{ NSFontAttributeName: font,
            NSParagraphStyleAttributeName: style };
}

- (void)fetchKitten
{
  NSOperationQueue *queue = [[NSOperationQueue alloc] init];

  NSInteger width = roundl(_kittenSize.width);
  NSInteger height = roundl(_kittenSize.height);

  NSURL *kittenURL = [NSURL URLWithString:[NSString stringWithFormat:@"http://placekitten.com/%zd/%zd", width, height]];
  [NSURLConnection sendAsynchronousRequest:[NSURLRequest requestWithURL:kittenURL]
                                     queue:queue
                         completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
                           if (connectionError || !data || !data.length)
                             return;

                           // set our image node's data
                           if (_imageNode.nodeLoaded) {
                             dispatch_sync(dispatch_get_main_queue(), ^{
                               // once the node's view is loaded, the node should only be used on the main thread
                               _imageNode.image = [UIImage imageWithData:data];
                             });
                           } else {
                             // if the node hasn't loaded, we can use it on a background thread
                             _imageNode.image = [UIImage imageWithData:data];
                           }
                         }];
}

- (CGSize)calculateSizeThatFits:(CGSize)constrainedSize
{
  CGSize imageSize = CGSizeMake(kImageSize, kImageSize);
  CGSize textSize = [_textNode measure:CGSizeMake(constrainedSize.width - kImageSize - 2 * kOuterPadding - kInnerPadding,
                                                  constrainedSize.height)];

  // ensure there's room for the text
  CGFloat requiredHeight = MAX(textSize.height, imageSize.height);
  return CGSizeMake(constrainedSize.width, requiredHeight + 2 * kOuterPadding);
}

- (void)layout
{
  CGFloat pixelHeight = 1.0f / [[UIScreen mainScreen] scale];
  _divider.frame = CGRectMake(0.0f, 0.0f, self.calculatedSize.width, pixelHeight);

  _imageNode.frame = CGRectMake(kOuterPadding, kOuterPadding, kImageSize, kImageSize);

  CGSize textSize = _textNode.calculatedSize;
  _textNode.frame = CGRectMake(kOuterPadding + kImageSize + kInnerPadding, kOuterPadding, textSize.width, textSize.height);
}

@end