Add Experimental Text Node Implementation (#259)

* Add experimental text node implementation, based on YYText

* Fix warnings and alert when unimplemented experimental features are used.

* Address feedback from review

* Extend the cthulog

* Update license headers

Source/Private/TextExperiment/Component/ASTextDebugOption.m

@@ -0,0 +1,139 @@
+//
+//  ASTextDebugOption.m
+//  Modified from YYText <https://github.com/ibireme/YYText>
+//
+//  Created by ibireme on 15/4/8.
+//  Copyright (c) 2015 ibireme.
+//
+//  This source code is licensed under the MIT-style license found in the
+//  LICENSE file in the root directory of this source tree.
+//
+
+#import "ASTextDebugOption.h"
+#import <libkern/OSAtomic.h>
+#import <pthread.h>
+
+static pthread_mutex_t _sharedDebugLock;
+static CFMutableSetRef _sharedDebugTargets = nil;
+static ASTextDebugOption *_sharedDebugOption = nil;
+
+static const void* _sharedDebugSetRetain(CFAllocatorRef allocator, const void *value) {
+  return value;
+}
+
+static void _sharedDebugSetRelease(CFAllocatorRef allocator, const void *value) {
+}
+
+void _sharedDebugSetFunction(const void *value, void *context) {
+  id<ASTextDebugTarget> target = (__bridge id<ASTextDebugTarget>)(value);
+  [target setDebugOption:_sharedDebugOption];
+}
+
+static void _initSharedDebug() {
+  static dispatch_once_t onceToken;
+  dispatch_once(&onceToken, ^{
+    pthread_mutex_init(&_sharedDebugLock, NULL);
+    CFSetCallBacks callbacks = kCFTypeSetCallBacks;
+    callbacks.retain = _sharedDebugSetRetain;
+    callbacks.release = _sharedDebugSetRelease;
+    _sharedDebugTargets = CFSetCreateMutable(CFAllocatorGetDefault(), 0, &callbacks);
+  });
+}
+
+static void _setSharedDebugOption(ASTextDebugOption *option) {
+  _initSharedDebug();
+  pthread_mutex_lock(&_sharedDebugLock);
+  _sharedDebugOption = option.copy;
+  CFSetApplyFunction(_sharedDebugTargets, _sharedDebugSetFunction, NULL);
+  pthread_mutex_unlock(&_sharedDebugLock);
+}
+
+static ASTextDebugOption *_getSharedDebugOption() {
+  _initSharedDebug();
+  pthread_mutex_lock(&_sharedDebugLock);
+  ASTextDebugOption *op = _sharedDebugOption;
+  pthread_mutex_unlock(&_sharedDebugLock);
+  return op;
+}
+
+static void _addDebugTarget(id<ASTextDebugTarget> target) {
+  _initSharedDebug();
+  pthread_mutex_lock(&_sharedDebugLock);
+  CFSetAddValue(_sharedDebugTargets, (__bridge const void *)(target));
+  pthread_mutex_unlock(&_sharedDebugLock);
+}
+
+static void _removeDebugTarget(id<ASTextDebugTarget> target) {
+  _initSharedDebug();
+  pthread_mutex_lock(&_sharedDebugLock);
+  CFSetRemoveValue(_sharedDebugTargets, (__bridge const void *)(target));
+  pthread_mutex_unlock(&_sharedDebugLock);
+}
+
+
+@implementation ASTextDebugOption
+
+- (id)copyWithZone:(NSZone *)zone {
+  ASTextDebugOption *op = [self.class new];
+  op.baselineColor = self.baselineColor;
+  op.CTFrameBorderColor = self.CTFrameBorderColor;
+  op.CTFrameFillColor = self.CTFrameFillColor;
+  op.CTLineBorderColor = self.CTLineBorderColor;
+  op.CTLineFillColor = self.CTLineFillColor;
+  op.CTLineNumberColor = self.CTLineNumberColor;
+  op.CTRunBorderColor = self.CTRunBorderColor;
+  op.CTRunFillColor = self.CTRunFillColor;
+  op.CTRunNumberColor = self.CTRunNumberColor;
+  op.CGGlyphBorderColor = self.CGGlyphBorderColor;
+  op.CGGlyphFillColor = self.CGGlyphFillColor;
+  return op;
+}
+
+- (BOOL)needDrawDebug {
+  if (self.baselineColor ||
+      self.CTFrameBorderColor ||
+      self.CTFrameFillColor ||
+      self.CTLineBorderColor ||
+      self.CTLineFillColor ||
+      self.CTLineNumberColor ||
+      self.CTRunBorderColor ||
+      self.CTRunFillColor ||
+      self.CTRunNumberColor ||
+      self.CGGlyphBorderColor ||
+      self.CGGlyphFillColor) return YES;
+  return NO;
+}
+
+- (void)clear {
+  self.baselineColor = nil;
+  self.CTFrameBorderColor = nil;
+  self.CTFrameFillColor = nil;
+  self.CTLineBorderColor = nil;
+  self.CTLineFillColor = nil;
+  self.CTLineNumberColor = nil;
+  self.CTRunBorderColor = nil;
+  self.CTRunFillColor = nil;
+  self.CTRunNumberColor = nil;
+  self.CGGlyphBorderColor = nil;
+  self.CGGlyphFillColor = nil;
+}
+
++ (void)addDebugTarget:(id<ASTextDebugTarget>)target {
+  if (target) _addDebugTarget(target);
+}
+
++ (void)removeDebugTarget:(id<ASTextDebugTarget>)target {
+  if (target) _removeDebugTarget(target);
+}
+
++ (ASTextDebugOption *)sharedDebugOption {
+  return _getSharedDebugOption();
+}
+
++ (void)setSharedDebugOption:(ASTextDebugOption *)option {
+  NSAssert([NSThread isMainThread], @"This method must be called on the main thread");
+  _setSharedDebugOption(option);
+}
+
+@end
+