//
//  LOTAnimatorNode.m
//  Pods
//
//  Created by brandon_withrow on 6/27/17.
//
//

#import "LOTAnimatorNode.h"
#import "LOTHelpers.h"
#import "LOTValueInterpolator.h"

NSInteger indentation_level = 0;

@implementation LOTAnimatorNode

- (instancetype _Nonnull)initWithInputNode:(LOTAnimatorNode *_Nullable)inputNode
                                    keyName:(NSString *_Nullable)keyname {
  self = [super init];
  if (self) {
    _keyname = keyname;
    _inputNode = inputNode;
  }
  return self;
}

/// To be overwritten by subclass. Defaults to YES
- (BOOL)needsUpdateForFrame:(NSNumber *)frame {
  return YES;
}

/// The node checks if local update or if upstream update required. If upstream update outputs are rebuilt. If local update local update is performed. Returns no if no action
- (BOOL)updateWithFrame:(NSNumber *_Nonnull)frame {
  return [self updateWithFrame:frame withModifierBlock:NULL forceLocalUpdate:NO];
}

- (BOOL)updateWithFrame:(NSNumber *_Nonnull)frame
      withModifierBlock:(void (^_Nullable)(LOTAnimatorNode * _Nonnull inputNode))modifier
       forceLocalUpdate:(BOOL)forceUpdate {
  if ([_currentFrame isEqual:frame] && !forceUpdate) {
    return NO;
  }
  if (ENABLE_DEBUG_LOGGING) [self logString:[NSString stringWithFormat:@"%lu %@ Checking for update", (unsigned long)self.hash, self.keyname]];
  BOOL localUpdate = [self needsUpdateForFrame:frame] || forceUpdate;
  if (localUpdate && ENABLE_DEBUG_LOGGING) {
    [self logString:[NSString stringWithFormat:@"%lu %@ Performing update", (unsigned long)self.hash, self.keyname]];
  }
  BOOL inputUpdated = [_inputNode updateWithFrame:frame
                                withModifierBlock:modifier
                                 forceLocalUpdate:forceUpdate];
  _currentFrame = frame;
  if (localUpdate) {
    [self performLocalUpdate];
    if (modifier) {
      modifier(self);
    }
  }
  
  if (inputUpdated || localUpdate) {
    [self rebuildOutputs];
  }
  return (inputUpdated || localUpdate);
}

- (void)forceSetCurrentFrame:(NSNumber *_Nonnull)frame {
  _currentFrame = frame;
}

- (void)logString:(NSString *)string {
  NSMutableString *logString = [NSMutableString string];
  [logString appendString:@"|"];
  for (int i = 0; i < indentation_level; i ++) {
    [logString appendString:@"  "];
  }
  [logString appendString:string];
  NSLog(@"%@ %@", NSStringFromClass([self class]), logString);
}

// TOBO BW Perf, make updates perform only when necessary. Currently everything in a node is updated
/// Performs any local content update and updates self.localPath
- (void)performLocalUpdate {
  self.localPath = [[LOTBezierPath alloc] init];
}

/// Rebuilds outputs by adding localPath to inputNodes output path.
- (void)rebuildOutputs {
  if (self.inputNode) {
    self.outputPath = [self.inputNode.outputPath copy];
    [self.outputPath LOT_appendPath:self.localPath];
  } else {
    self.outputPath = self.localPath;
  }
}

- (void)setPathShouldCacheLengths:(BOOL)pathShouldCacheLengths {
  _pathShouldCacheLengths = pathShouldCacheLengths;
  self.inputNode.pathShouldCacheLengths = pathShouldCacheLengths;
}

- (void)searchNodesForKeypath:(LOTKeypath * _Nonnull)keypath {
  [self.inputNode searchNodesForKeypath:keypath];
  if ([keypath pushKey:self.keyname]) {
    // Matches self. Check interpolators
    if (keypath.endOfKeypath) {
      // Add self
      [keypath addSearchResultForCurrentPath:self];
    } else if (self.valueInterpolators[keypath.currentKey] != nil) {
      [keypath pushKey:keypath.currentKey];
      // We have a match!
      [keypath addSearchResultForCurrentPath:self];
      [keypath popKey];
    }
    [keypath popKey];
  }
}

- (void)setValueDelegate:(id<LOTValueDelegate> _Nonnull)delegate
              forKeypath:(LOTKeypath * _Nonnull)keypath {
  if ([keypath pushKey:self.keyname]) {
    // Matches self. Check interpolators
    LOTValueInterpolator *interpolator = self.valueInterpolators[keypath.currentKey];
    if (interpolator) {
      // We have a match!
      [interpolator setValueDelegate:delegate];
    }
    [keypath popKey];
  }
  [self.inputNode setValueDelegate:delegate forKeypath:keypath];
}

@end