[css] initial debugging support via "description" type methods that w…

…ill do a dry run of the style sheet and spit out objective-c for you to look at.

examples/css/CSSDemo/RootViewController.m

@@ -78,6 +78,8 @@ - (void)loadView {
     [_dom registerView:box withCSSClass:@"colorBox" andId:[NSString stringWithFormat:@"box%d",i]];
   }
   [_activityIndicator startAnimating];
+
+  NSLog(@"%@", [_dom descriptionForAllViews]);
 }
 
 -(void)viewWillLayoutSubviews

src/css/src/NIDOM.h

@@ -88,6 +88,9 @@ _dom = [[NIDOM alloc] initWithStylesheet:stylesheet];
 
 -(UIView*)viewById: (NSString*) viewId;
 
+-(NSString*) descriptionForView: (UIView*) view withName: (NSString*) viewName;
+-(NSString*) descriptionForAllViews;
+
 @property (nonatomic,unsafe_unretained) id target;
 @end
 
@@ -192,3 +195,21 @@ _dom = [[NIDOM alloc] initWithStylesheet:stylesheet];
  *
  *      @fn NIDOM::target
  */
+
+/** @name Debugging */
+
+/**
+ * Describe what would be done to view given the existing registrations for it. In other words, you
+ * must call one of the register view variants first before asking for a description. The current
+ * implementations return actual objective-c code, using viewName as the target. This allows you to
+ * theoretically replace the CSS infrastructure with generated code, if you choose to. More importantly,
+ * it allows you to debug what's happening with view styling.
+ *
+ *      @fn NIDOM::descriptionForView:withName:
+ */
+
+/**
+ * Call descriptionForView for all registered views, in the order they would be applied during refresh
+ *
+ *      @fn NIDOM::descriptionForAllViews
+ */

src/css/src/NIDOM.m

@@ -297,4 +297,53 @@ -(UIView *)viewById:(NSString *)viewId
   return [_idToViewMap objectForKey:viewId];
 }
 
+///////////////////////////////////////////////////////////////////////////////////////////////////
+-(NSString *)descriptionForView:(UIView *)view withName:(NSString *)viewName
+{
+  NSMutableString *description = [[NSMutableString alloc] init];
+  BOOL appendedStyleInfo = NO;
+
+  for (NSString *selector in [_viewToSelectorsMap objectForKey:[self keyForView:view]]) {
+    BOOL appendedSelectorInfo = NO;
+    NSString *additional = nil;
+    if (self.parent) {
+      additional = [self.parent.stylesheet descriptionForView: view withClassName: selector inDOM:self andViewName: viewName];
+      if (additional && additional.length) {
+        if (!appendedStyleInfo) { appendedStyleInfo = YES; [description appendFormat:@"// Styles for %@\n", viewName]; }
+        if (!appendedSelectorInfo) { appendedSelectorInfo = YES; [description appendFormat:@"// Selector %@\n", selector]; }
+        [description appendString:additional];
+      }
+    }
+    additional = [_stylesheet descriptionForView:view withClassName: selector inDOM:self andViewName: viewName];
+    if (additional && additional.length) {
+      if (!appendedStyleInfo) { appendedStyleInfo = YES; [description appendFormat:@"// Styles for %@\n", viewName]; }
+      if (!appendedSelectorInfo) { appendedSelectorInfo = YES; [description appendFormat:@"// Selector %@\n", selector]; }
+      [description appendString:additional];
+    }
+  }
+  return description;
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+-(NSString *)descriptionForAllViews {
+  NSMutableString *description = [[NSMutableString alloc] init];
+  int viewCount = 0;
+  for (UIView *view in _registeredViews) {
+    [description appendString:@"\n///////////////////////////////////////////////////////////////////////////////////////////////////\n"];
+    viewCount++;
+    // This is a little hokey - because we don't get individual view names we have to come up with some.
+    __block NSString *vid = nil;
+    [[_viewToSelectorsMap objectForKey:[self keyForView:view]] enumerateObjectsUsingBlock:^(NSString *selector, NSUInteger idx, BOOL *stop) {
+      if ([selector hasPrefix:@"#"]) {
+        vid = [selector substringFromIndex:1];
+        *stop = YES;
+      }
+    }];
+    if (vid) {
+      [description appendFormat:@"UIView *%@_%d = [dom viewById: @\"#%@\"];\n", [view class], viewCount, vid];
+    }
+    [description appendString:[self descriptionForView:view withName:[NSString stringWithFormat:@"%@_%d", [view class], viewCount]]];
+  }
+  return description;
+}
 @end

src/css/src/NIStyleable.h

@@ -60,4 +60,11 @@
  */
 - (void)applyStyleWithRuleSet:(NICSSRuleset *)ruleSet forPseudoClass: (NSString*) pseudo inDOM: (NIDOM*) dom;
 
+/**
+ * Return a string describing what would be done with the view. The current implementations return actual
+ * Objective-C using the view name as the message target. The intent is to allow developers to debug
+ * the logic, but also to be able to strip out the CSS infrastructure if desired and replace it with manual code.
+ */
+- (NSString*) descriptionWithRuleSet: (NICSSRuleset*) ruleSet forPseudoClass: (NSString*) pseudo inDOM: (NIDOM*) dom withViewName: (NSString*) name;
+
 @end

src/css/src/NIStylesheet.h

@@ -64,6 +64,8 @@ extern NSString* const NIStylesheetDidChangeNotification;
 
 - (void)applyStyleToView:(UIView *)view withClassName:(NSString *)className inDOM: (NIDOM*)dom;
 
+- (NSString*)descriptionForView:(UIView *)view withClassName:(NSString *)className inDOM: (NIDOM*)dom andViewName: (NSString*) viewName;
+
 - (NICSSRuleset *)rulesetForClassName:(NSString *)className;
 
 /**
@@ -141,3 +143,12 @@ extern NSString* const NIStylesheetDidChangeNotification;
  *      @param className  Either the view's class as a string using NSStringFromClass([view class]);
  *                        or a CSS class selector such as ".myClassSelector".
  */
+
+/** @name Debugging */
+
+/**
+ * Build a string describing the rules that would be applied to the view given a css class name in a DOM.
+ * Current implementations output Objective-C code that use viewName as the target.
+ *
+ *      @fn NIStylesheet::descriptionForView:withClassName:inDOM:andViewName:
+ */

src/css/src/NIStylesheet.m

@@ -226,6 +226,24 @@ - (void)addStylesheet:(NIStylesheet *)stylesheet {
   }
 }
 
+///////////////////////////////////////////////////////////////////////////////////////////////////
+- (NSString*)descriptionForView:(UIView *)view withClassName:(NSString *)className inDOM:(NIDOM *)dom andViewName:(NSString *)viewName {
+  NSMutableString *description = [[NSMutableString alloc] init];
+  NICSSRuleset *ruleset = [self rulesetForClassName:className];
+  if (nil != ruleset) {
+    NSRange r = [className rangeOfString:@":"];
+    if ([view respondsToSelector:@selector(descriptionWithRuleSet:forPseudoClass:inDOM:withViewName:)]) {
+      if (r.location != NSNotFound) {
+        [description appendString:[(id<NIStyleable>)view descriptionWithRuleSet:ruleset forPseudoClass:[className substringFromIndex:r.location+1] inDOM:dom withViewName:viewName]];
+      } else {
+        [description appendString:[(id<NIStyleable>)view descriptionWithRuleSet:ruleset forPseudoClass:nil inDOM:dom withViewName:viewName]];
+      }
+    } else {
+      [description appendFormat:@"// Description not supported for %@ with selector %@\n", view, className];
+    }
+  }
+  return description;
+}
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////////////////////////////

src/css/src/UIView+NIStyleable.h

@@ -40,13 +40,21 @@ extern NSString* const NICSSViewBackgroundColorKey;
 - (void)applyViewStyleWithRuleSet:(NICSSRuleset *)ruleSet DEPRECATED_ATTRIBUTE;
 
 /**
- * Applies the given rule set to this view. Call applyViewStyleWithRuleSet:inDOM: instead.
+ * Applies the given rule set to this view.
  *
  * This method is exposed primarily for subclasses to use when implementing the
  * applyStyleWithRuleSet: method from NIStyleable.
  */
 - (void)applyViewStyleWithRuleSet:(NICSSRuleset *)ruleSet inDOM: (NIDOM*) dom;
 
+/**
+ * Describes the given rule set when applied to this view.
+ *
+ * This method is exposed primarily for subclasses to use when implementing the
+ * descriptionWithRuleSetFor:forPseudoClass:inDOM:withViewName: method from NIStyleable.
+ */
+- (NSString*) descriptionWithRuleSetForView: (NICSSRuleset*) ruleSet forPseudoClass: (NSString*) pseudo inDOM: (NIDOM*) dom withViewName: (NSString*) name;
+
 /**
  * Build a view hierarchy. The array is a list of view specs, where viewSpec is a loosely formatted
  * sequence delineated by UIViews. After a UIView, the type of the next object determines what is done