finished preprocessors

Sources/Motion+Start.swift

@@ -102,13 +102,12 @@ fileprivate extension Motion {
     
     /// Prepares the preprocessors.
     func preparePreprocessors() {
-        for x in [
-            IgnoreSubviewTransitionsPreprocessor(),
-            MatchPreprocessor(),
-            SourcePreprocessor(),
-            CascadePreprocessor(),
-            TransitionPreprocessor(motion: self),
-            DurationPreprocessor()] as [MotionPreprocessor] {
+        for x in [IgnoreSubviewTransitionsPreprocessor(),
+                  ConditionalPreprocessor(),
+                  TransitionPreprocessor(),
+                  MatchPreprocessor(),
+                  SourcePreprocessor(),
+                  CascadePreprocessor()] as [MotionPreprocessor] {
                 preprocessors.append(x)
         }
         

Sources/Motion.swift

@@ -441,7 +441,7 @@ public extension Motion {
         }
         
         let s = MotionTransitionState(transitions: transitions)
-        let v = context.transitionPairedView(for: view) ?? view
+        let v = context.pairedView(for: view) ?? view
         
         for a in animators {
             a.apply(state: s, to: v)

Sources/MotionContext.swift

@@ -148,7 +148,7 @@ public extension MotionContext {
      source and destination view controllers.
      - Returns: An optional UIView.
      */
-    func transitionPairedView(for view: UIView) -> UIView? {
+    func pairedView(for view: UIView) -> UIView? {
         if let i = view.motionIdentifier {
             if view == sourceView(for: i) {
                 return destinationView(for: i)
@@ -316,7 +316,7 @@ public extension MotionContext {
             hide(view: view)
         }
         
-        if let pairedView = transitionPairedView(for: view), let pairedSnapshot = viewToSnapshot[pairedView] {
+        if let pairedView = pairedView(for: view), let pairedSnapshot = viewToSnapshot[pairedView] {
             let siblingViews = pairedView.superview!.subviews
             let nextSiblings = siblingViews[siblingViews.index(of: pairedView)! + 1..<siblingViews.count]
             

Sources/MotionPlugin.swift

@@ -28,7 +28,7 @@
 
 import UIKit
 
-class MotionPlugin: BaseMotionPreprocessor, MotionAnimator {
+class MotionPlugin: MotionCorePreprocessor, MotionAnimator {
   /**
     Determines whether or not to receive `seekTo` callback on every frame.
    

Sources/MotionTransitionState.swift

@@ -45,6 +45,9 @@ public struct MotionTransitionState {
     /// The initial state that the transition will start at.
     internal var beginState: MotionTransitionStateWrapper?
     
+    
+    public var conditionalTransitions: [((MotionConditionalContext) -> Bool, [MotionTransition])]?
+    
     /// The start state if there is a match in the desition view controller.
     public var beginStateIfMatched: [MotionTransition]?
 

Sources/Preprocessors/CascadePreprocessor.swift

@@ -60,7 +60,7 @@ public enum CascadeDirection {
     }
 }
 
-class CascadePreprocessor: BaseMotionPreprocessor {
+class CascadePreprocessor: MotionCorePreprocessor {
     /**
      Processes the transitionary views.
      - Parameter fromViews: An Array of UIViews.
@@ -91,10 +91,10 @@ class CascadePreprocessor: BaseMotionPreprocessor {
                 let delay = TimeInterval(i) * deltaTime + initialDelay
 
                 func applyDelay(view: UIView) {
-                    if context.transitionPairedView(for: view) == nil {
+                    if context.pairedView(for: view) == nil {
                         context[view]?.delay = delay
                     
-                    } else if delayMatchedViews, let paired = context.transitionPairedView(for: view) {
+                    } else if delayMatchedViews, let paired = context.pairedView(for: view) {
                         context[view]?.delay = finalDelay
                         context[paired]?.delay = finalDelay
                     }

Sources/Preprocessors/ConditionalPreprocessor.swift

+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (C) 2017, Daniel Dahan and CosmicMind, Inc. <http://cosmicmind.com>.
+ * All rights reserved.
+ *
+ * Original Inspiration & Author
+ * Copyright (c) 2016 Luke Zhao <me@lkzhao.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * 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 THE
+ * AUTHORS OR COPYRIGHT HOLDERS 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 UIKit
+
+public struct MotionConditionalContext {
+    internal weak var motion: Motion!
+    public weak var view: UIView!
+    
+    public private(set) var isAppearing: Bool
+    
+    public var isPresenting: Bool {
+        return motion.isPresenting
+    }
+    
+    public var isTabBarController: Bool {
+        return motion.isTabBarController
+    }
+    
+    public var isNavigationController: Bool {
+        return motion.isNavigationController
+    }
+    
+    public var isMatched: Bool {
+        return matchedView != nil
+    }
+    
+    public var isAncestorViewMatched: Bool {
+        return matchedAncestorView != nil
+    }
+    
+    public var matchedView: UIView? {
+        return motion.context.pairedView(for: view)
+    }
+    
+    public var matchedAncestorView: (UIView, UIView)? {
+        var current = view.superview
+        
+        while let ancestor = current, ancestor != motion.context.container {
+            if let pairedView = motion.context.pairedView(for: ancestor) {
+                return (ancestor, pairedView)
+            }
+            
+            current = ancestor.superview
+        }
+        
+        return nil
+    }
+    
+    public var fromViewController: UIViewController {
+        return motion.fromViewController!
+    }
+    
+    public var toViewController: UIViewController {
+        return motion.toViewController!
+    }
+    
+    public var currentViewController: UIViewController {
+        return isAppearing ? toViewController : fromViewController
+    }
+    
+    public var otherViewController: UIViewController {
+        return isAppearing ? fromViewController : toViewController
+    }
+}
+
+class ConditionalPreprocessor: MotionCorePreprocessor {
+    override func process(fromViews: [UIView], toViews: [UIView]) {
+        process(views: fromViews, isAppearing: false)
+        process(views: toViews, isAppearing: true)
+    }
+    
+    func process(views: [UIView], isAppearing: Bool) {
+        for v in views {
+            guard let conditionalTransitions = context[v]?.conditionalTransitions else {
+                continue
+            }
+            
+            for (condition, transitions) in conditionalTransitions {
+                if condition(MotionConditionalContext(motion: motion, view: v, isAppearing: isAppearing)) {
+                    context[v]!.append(contentsOf: transitions)
+                }
+            }
+        }
+    }
+}
+

Sources/Preprocessors/DurationPreprocessor.swift

-/*
- * The MIT License (MIT)
- *
- * Copyright (C) 2017, Daniel Dahan and CosmicMind, Inc. <http://cosmicmind.com>.
- * All rights reserved.
- *
- * Original Inspiration & Author
- * Copyright (c) 2016 Luke Zhao <me@lkzhao.com>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * 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 THE
- * AUTHORS OR COPYRIGHT HOLDERS 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 UIKit
-
-class DurationPreprocessor: BaseMotionPreprocessor {
-    /**
-     Processes the transitionary views.
-     - Parameter fromViews: An Array of UIViews.
-     - Parameter toViews: An Array of UIViews.
-     */
-    override func process(fromViews: [UIView], toViews: [UIView]) {
-        var maxDuration: TimeInterval = 0
-        maxDuration = applyOptimizedDurationIfNoDuration(views: fromViews)
-        maxDuration = max(maxDuration, applyOptimizedDurationIfNoDuration(views: toViews))
-        setDurationForInfiniteDuration(views: fromViews, duration: maxDuration)
-        setDurationForInfiniteDuration(views: toViews, duration: maxDuration)
-    }
-
-    /**
-     Retrieves the optimized duration for a given UIView.
-     - Parameter for view: A UIView.
-     - Returns: A TimeInterval.
-     */
-    func optimizedDuration(for view: UIView) -> TimeInterval {
-        let v = context[view]!
-        
-        return view.optimizedDuration(position: context.container.convert(view.layer.position, from: view.superview),
-                                              size: v.size,
-                                         transform: v.transform)
-    }
-
-    /**
-     Applies the optimized duration for an Array of UIViews.
-     - Parameter views: An Array of UIViews.
-     - Returns: A TimeInterval.
-    */
-    func applyOptimizedDurationIfNoDuration(views: [UIView]) -> TimeInterval {
-        var d: TimeInterval = 0
-        
-        for v in views where nil != context[v] {
-            if nil == context[v]?.duration {
-                context[v]!.duration = optimizedDuration(for: v)
-            }
-            
-            d = .infinity == context[v]!.duration! ?
-                    max(d, optimizedDuration(for: v)) :
-                    max(d, context[v]!.duration!)
-        }
-        
-        return d
-    }
-
-    /**
-     Sets the duration if the duration of a transition is set to `.infinity`.
-     - Parameter views: An Array of UIViews.
-     - Parameter duration: A TimeInterval.
-     */
-    func setDurationForInfiniteDuration(views: [UIView], duration: TimeInterval) {
-        for v in views where .infinity == context[v]?.duration {
-            context[v]!.duration = duration
-        }
-    }
-}

Sources/Preprocessors/IgnoreSubviewModifiersPreprocessor.swift

@@ -28,7 +28,7 @@
 
 import UIKit
 
-class IgnoreSubviewTransitionsPreprocessor: BaseMotionPreprocessor {
+class IgnoreSubviewTransitionsPreprocessor: MotionCorePreprocessor {
     /**
      Processes the transitionary views.
      - Parameter fromViews: An Array of UIViews.
@@ -64,12 +64,12 @@ class IgnoreSubviewTransitionsPreprocessor: BaseMotionPreprocessor {
     }
 }
 
-extension IgnoreSubviewTransitionsPreprocessor {
+fileprivate extension IgnoreSubviewTransitionsPreprocessor {
     /**
      Clears the transition for a given view's subviews.
      - Parameter for view: A UIView.
      */
-    fileprivate func cleanSubviewTransitions(for view: UIView) {
+    func cleanSubviewTransitions(for view: UIView) {
         for v in view.subviews {
             context[v] = nil
             cleanSubviewTransitions(for: v)

Sources/Preprocessors/MatchPreprocessor.swift

@@ -28,7 +28,7 @@
 
 import UIKit
 
-class MatchPreprocessor: BaseMotionPreprocessor {
+class MatchPreprocessor: MotionCorePreprocessor {
     /**
      Processes the transitionary views.
      - Parameter fromViews: An Array of UIViews.
@@ -36,23 +36,17 @@ class MatchPreprocessor: BaseMotionPreprocessor {
      */
     override func process(fromViews: [UIView], toViews: [UIView]) {
         for tv in toViews {
-            guard let i = tv.motionIdentifier, let fv = context.sourceView(for: i) else { continue }
+            guard let motionIdentifier = tv.motionIdentifier, let fv = context.sourceView(for: motionIdentifier) else {
+                continue
+            }
             
             var tvState = context[tv] ?? MotionTransitionState()
             var fvState = context[fv] ?? MotionTransitionState()
             
-            if let v = tvState.beginStateIfMatched {
-                tvState.append(.beginWith(transitions: v))
-            }
-            
-            if let v = fvState.beginStateIfMatched {
-                fvState.append(.beginWith(transitions: v))
-            }
-            
-            tvState.motionIdentifier = i
-            tvState.opacity = 0
+            // match is just a two-way source effect
+            tvState.motionIdentifier = motionIdentifier
+            fvState.motionIdentifier = motionIdentifier
             
-            fvState.motionIdentifier = i
             fvState.arc = tvState.arc
             fvState.duration = tvState.duration
             fvState.timingFunction = tvState.timingFunction
@@ -62,20 +56,34 @@ class MatchPreprocessor: BaseMotionPreprocessor {
             let forceNonFade = tvState.nonFade || fvState.nonFade
             let isNonOpaque = !fv.isOpaque || fv.alpha < 1 || !tv.isOpaque || tv.alpha < 1
             
-            if !forceNonFade && isNonOpaque {
-                // Cross fade if from/toViews are not opaque.
+            if context.insertToViewFirst {
                 fvState.opacity = 0
                 
+                if !forceNonFade && isNonOpaque {
+                    tvState.opacity = 0
+                
+                } else {
+                    tvState.opacity = nil
+                    
+                    if !tv.layer.masksToBounds && tvState.displayShadow {
+                        fvState.displayShadow = false
+                    }
+                }
+                
             } else {
-                // No cross fade in this case, fromView is always displayed during the transition.
-                fvState.opacity = nil
+                tvState.opacity = 0
                 
-                /**
-                 We dont want two shadows showing up. Therefore we disable toView's
-                 shadow when fromView is able to display its shadow.
-                 */
-                if !fv.layer.masksToBounds && fvState.displayShadow {
-                    tvState.displayShadow = false
+                if !forceNonFade && isNonOpaque {
+                    // cross fade if from/toViews are not opaque
+                    fvState.opacity = 0
+                } else {
+                    // no cross fade in this case, fromView is always displayed during the transition.
+                    fvState.opacity = nil
+                    
+                    // we dont want two shadows showing up. Therefore we disable toView's shadow when fromView is able to display its shadow
+                    if !fv.layer.masksToBounds && fvState.displayShadow {
+                        tvState.displayShadow = false
+                    }
                 }
             }
             

Sources/Preprocessors/BaseMotionPreprocessor.swift → Sources/Preprocessors/MotionCorePreprocessor.swift

@@ -28,7 +28,7 @@
 
 import UIKit
 
-class BaseMotionPreprocessor: MotionPreprocessor {
+class MotionCorePreprocessor: MotionPreprocessor {
     weak public var motion: Motion!
     
     /// A reference to the MotionContext.

Sources/Preprocessors/SourcePreprocessor.swift

@@ -28,7 +28,7 @@
 
 import UIKit
 
-class SourcePreprocessor: BaseMotionPreprocessor {
+class SourcePreprocessor: MotionCorePreprocessor {
     /**
      Processes the transitionary views.
      - Parameter fromViews: An Array of UIViews.

Sources/Preprocessors/TransitionPreprocessor.swift

@@ -172,16 +172,7 @@ public enum MotionTransitionType {
     }
 }
 
-class TransitionPreprocessor: BaseMotionPreprocessor {
-    /**
-     An initializer that accepts a given Motion instance.
-     - Parameter motion: A Motion.
-     */
-    init(motion: Motion) {
-        super.init()
-        self.motion = motion
-    }
-
+class TransitionPreprocessor: MotionCorePreprocessor {
     /**
      Processes the transitionary views.
      - Parameter fromViews: An Array of UIViews.