Web Animations: Add InterpolableValue hierarchy.

Source/core/animation/InterpolableValue.h

Index: Source/core/animation/InterpolableValue.h
diff --git a/Source/core/animation/InterpolableValue.h b/Source/core/animation/InterpolableValue.h
new file mode 100644
index 0000000000000000000000000000000000000000..2111b55890137029fd1365989b56f0492b9042dd
--- /dev/null
+++ b/Source/core/animation/InterpolableValue.h
@@ -0,0 +1,130 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef InterpolableValue_h
+#define InterpolableValue_h
+
+#include "wtf/OwnPtr.h"
+#include "wtf/PassOwnPtr.h"
+
+namespace WebCore {
+
+class InterpolableValue {
+public:
+    virtual bool isNumber() const { return false; }
+    virtual bool isBool() const { return false; }
+    virtual bool isList() const { return false; }
+
+    virtual ~InterpolableValue() { }
+    virtual PassOwnPtr<InterpolableValue> clone() const = 0;
+
+private:
+    virtual PassOwnPtr<InterpolableValue> interpolate(const InterpolableValue &to, const double progress) const = 0;
+
+    // TODO: Replace this with Interpolation when committing Interpolation
+    // patch. Refactor InterpolableValueTest to test via Interpolation
+    // interface.
+    friend class AnimationInterpolableValueTest;
+
+    // Keep interpolate private, but allow calls within the hierarchy without
+    // knowledge of type.
+    friend class InterpolableNumber;
+    friend class InterpolableBool;
+    friend class InterpolableList;
+};
+
+class InterpolableNumber : public InterpolableValue {
+public:
+    static PassOwnPtr<InterpolableNumber> create(double value)
+    {
+        return adoptPtr(new InterpolableNumber(value));
+    }
+
+    virtual bool isNumber() const OVERRIDE FINAL { return true; }
+    double value() const { return m_value; }
+    virtual PassOwnPtr<InterpolableValue> clone() const OVERRIDE FINAL { return create(m_value); }
+
+private:
+    virtual PassOwnPtr<InterpolableValue> interpolate(const InterpolableValue &to, const double progress) const OVERRIDE FINAL;
+    double m_value;
+
+    InterpolableNumber(double value)
+        : m_value(value)
+    { }
+
+};
+
+class InterpolableBool : public InterpolableValue {
+public:
+    static PassOwnPtr<InterpolableBool> create(bool value)
+    {
+        return adoptPtr(new InterpolableBool(value));
+    }
+
+    virtual bool isBool() const OVERRIDE FINAL { return true; }
+    bool value() const { return m_value; }
+    virtual PassOwnPtr<InterpolableValue> clone() const OVERRIDE FINAL { return create(m_value); }
+
+private:
+    virtual PassOwnPtr<InterpolableValue> interpolate(const InterpolableValue &to, const double progress) const OVERRIDE FINAL;
+    bool m_value;
+
+    InterpolableBool(bool value)
+        : m_value(value)
+    { }
+
+};
+
+class InterpolableList : public InterpolableValue {
+public:
+    static PassOwnPtr<InterpolableList> create(const InterpolableList &other)
+    {
+        return adoptPtr(new InterpolableList(other));
+    }
+
+    static PassOwnPtr<InterpolableList> create(size_t size)
+    {
+        return adoptPtr(new InterpolableList(size));
+    }
+
+    virtual bool isList() const OVERRIDE FINAL { return true; }
+    void set(size_t position, PassOwnPtr<InterpolableValue> value)
+    {
+        ASSERT(position < m_size);
+        m_values.get()[position] = value;
+    }
+    const InterpolableValue* get(size_t position) const
+    {
+        ASSERT(position < m_size);
+        return m_values.get()[position].get();
+    }
+    virtual PassOwnPtr<InterpolableValue> clone() const OVERRIDE FINAL { return create(*this); }
+
+private:
+    virtual PassOwnPtr<InterpolableValue> interpolate(const InterpolableValue &other, const double progress) const OVERRIDE FINAL;
+    InterpolableList(size_t size)
+        : m_size(size)
+    {
+        m_values = adoptArrayPtr(new OwnPtr<InterpolableValue>[size]);
+    }
+
+    InterpolableList(const InterpolableList& other)
+        : m_size(other.m_size)
+    {
+        m_values = adoptArrayPtr(new OwnPtr<InterpolableValue>[m_size]);
+        for (size_t i = 0; i < m_size; i++)
+            set(i, other.m_values.get()[i]->clone());
+    }
+
+    size_t m_size;
+    OwnPtr<OwnPtr<InterpolableValue>[]> m_values;
+};
+
+DEFINE_TYPE_CASTS(InterpolableNumber, InterpolableValue, value, value->isNumber(), value.isNumber());
+DEFINE_TYPE_CASTS(InterpolableBool, InterpolableValue, value, value->isBool(), value.isBool());
+DEFINE_TYPE_CASTS(InterpolableList, InterpolableValue, value, value->isList(), value.isList());
+
+}
+
+#endif