#import "UIViewController_TourGuide.h"
#import "NSObject_Swizzle.h"

static char tourStepsKey;

@implementation UIViewController (TourGuide)

+ (void)load {
  static dispatch_once_t onceToken;
  dispatch_once(&onceToken, ^{
    [self swizzleInstanceSelector:@selector(viewWillAppear:) 
                  withNewSelector:@selector(tourGuideWillAppear:)];
  });
}

- (NSArray*) getTourSteps {
  return objc_getAssociatedObject(self, &tourStepsKey);
}

- (void) setTourSteps:(NSArray*)tourSteps {
  objc_setAssociatedObject(self, &tourStepsKey,
    tourSteps, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (void) displayTour {
  // run the tour, and save the fact it was run
}

- (BOOL) isTourRan {
  // return TRUE if tour has been run
}

- (void) tourGuideWillAppear:(BOOL)animated {
  // call the old implementation, now under the new message signature
  [self tourGuideWillAppear:animated];
  
  if (![self isTourRan]) {
    [self displayTour];
  }
}

@end