// Copyright 2021 The Tint Authors.
//
// 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 SRC_TINT_TRANSFORM_SINGLE_ENTRY_POINT_H_
#define SRC_TINT_TRANSFORM_SINGLE_ENTRY_POINT_H_

#include <string>

#include "src/tint/transform/transform.h"

namespace tint::transform {

/// Strip all but one entry point a module.
///
/// All module-scope variables, types, and functions that are not used by the
/// target entry point will also be removed.
class SingleEntryPoint : public Castable<SingleEntryPoint, Transform> {
 public:
  /// Configuration options for the transform
  struct Config : public Castable<Config, Data> {
    /// Constructor
    /// @param entry_point the name of the entry point to keep
    explicit Config(std::string entry_point = "");

    /// Copy constructor
    Config(const Config&);

    /// Destructor
    ~Config() override;

    /// Assignment operator
    /// @returns this Config
    Config& operator=(const Config&);

    /// The name of the entry point to keep.
    std::string entry_point_name;
  };

  /// Constructor
  SingleEntryPoint();

  /// Destructor
  ~SingleEntryPoint() override;

 protected:
  /// Runs the transform using the CloneContext built for transforming a
  /// program. Run() is responsible for calling Clone() on the CloneContext.
  /// @param ctx the CloneContext primed with the input program and
  /// ProgramBuilder
  /// @param inputs optional extra transform-specific input data
  /// @param outputs optional extra transform-specific output data
  void Run(CloneContext& ctx,
           const DataMap& inputs,
           DataMap& outputs) const override;
};

}  // namespace tint::transform

#endif  // SRC_TINT_TRANSFORM_SINGLE_ENTRY_POINT_H_