// Copyright 2014 The Cobalt Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef COBALT_CSSOM_SCALE_FUNCTION_H_
#define COBALT_CSSOM_SCALE_FUNCTION_H_

#include <string>

#include "base/memory/ref_counted.h"
#include "base/strings/stringprintf.h"
#include "cobalt/base/polymorphic_equatable.h"
#include "cobalt/cssom/transform_function.h"

namespace cobalt {
namespace cssom {

class TransformFunctionVisitor;

// Scale function specifies a 2D scale operation by the scaling vector.
//   https://www.w3.org/TR/css-transforms-1/#funcdef-scale
class ScaleFunction : public TransformFunction {
 public:
  ScaleFunction(float x_factor, float y_factor)
      : x_factor_(x_factor), y_factor_(y_factor) {}

  void Accept(TransformFunctionVisitor* visitor) const override;

  float x_factor() const { return x_factor_; }
  float y_factor() const { return y_factor_; }

  std::string ToString() const override {
    if (y_factor_ == 1.0f) {
      return base::StringPrintf("scaleX(%.7g)", x_factor_);
    }
    if (x_factor_ == 1.0f) {
      return base::StringPrintf("scaleY(%.7g)", y_factor_);
    }
    return base::StringPrintf("scale(%.7g, %.7g)", x_factor_, y_factor_);
  }

  math::Matrix3F ToMatrix(const math::SizeF& used_size,
                          const scoped_refptr<ui_navigation::NavItem>&
                              used_ui_nav_focus) const override;

  bool operator==(const ScaleFunction& other) const {
    return x_factor_ == other.x_factor_ && y_factor_ == other.y_factor_;
  }

  DEFINE_POLYMORPHIC_EQUATABLE_TYPE(ScaleFunction);

 private:
  const float x_factor_;
  const float y_factor_;
};

}  // namespace cssom
}  // namespace cobalt

#endif  // COBALT_CSSOM_SCALE_FUNCTION_H_