// Copyright 2020 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_VALIDATOR_VALIDATOR_TEST_HELPER_H_
#define SRC_VALIDATOR_VALIDATOR_TEST_HELPER_H_

#include <functional>
#include <memory>
#include <utility>
#include <vector>

#include "src/ast/builder.h"
#include "src/type/void_type.h"
#include "src/type_determiner.h"
#include "src/validator/validator_impl.h"

namespace tint {

/// A helper for testing validation
class ValidatorTestHelper : public ast::BuilderWithModule {
 public:
  /// Constructor
  ValidatorTestHelper();
  ~ValidatorTestHelper() override;

  /// Builds and returns a validator from the module.
  /// @note The validator is only built once. Multiple calls to Build() will
  /// return the same ValidatorImpl without rebuilding.
  /// @return the built validator
  ValidatorImpl& Build() {
    if (val_) {
      return *val_;
    }
    val_ = std::make_unique<ValidatorImpl>(mod);
    for (auto* var : vars_for_testing_) {
      val_->RegisterVariableForTesting(var);
    }
    return *val_;
  }

  /// A handle to type_determiner
  /// @returns a pointer to the type_determiner object
  TypeDeterminer* td() const { return td_.get(); }

  /// Inserts a variable into the current scope.
  /// @param var the variable to register.
  void RegisterVariable(ast::Variable* var) {
    vars_for_testing_.emplace_back(var);
    td_->RegisterVariableForTesting(var);
  }

 private:
  std::unique_ptr<TypeDeterminer> td_;
  std::unique_ptr<ValidatorImpl> val_;
  std::vector<ast::Variable*> vars_for_testing_;
};

}  // namespace tint

#endif  // SRC_VALIDATOR_VALIDATOR_TEST_HELPER_H_