// 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.

#include <memory>
#include <vector>

#include "gtest/gtest.h"
#include "src/ast/constant_id_decoration.h"
#include "src/ast/decorated_variable.h"
#include "src/ast/float_literal.h"
#include "src/ast/module.h"
#include "src/ast/scalar_constructor_expression.h"
#include "src/ast/type/array_type.h"
#include "src/ast/type/f32_type.h"
#include "src/ast/type_constructor_expression.h"
#include "src/ast/variable.h"
#include "src/writer/msl/generator_impl.h"

namespace tint {
namespace writer {
namespace msl {
namespace {

using MslGeneratorImplTest = testing::Test;

TEST_F(MslGeneratorImplTest, Emit_ModuleConstant) {
  ast::type::F32Type f32;
  ast::type::ArrayType ary(&f32, 3);

  ast::ExpressionList exprs;
  exprs.push_back(std::make_unique<ast::ScalarConstructorExpression>(
      std::make_unique<ast::FloatLiteral>(&f32, 1.0f)));
  exprs.push_back(std::make_unique<ast::ScalarConstructorExpression>(
      std::make_unique<ast::FloatLiteral>(&f32, 2.0f)));
  exprs.push_back(std::make_unique<ast::ScalarConstructorExpression>(
      std::make_unique<ast::FloatLiteral>(&f32, 3.0f)));

  auto var =
      std::make_unique<ast::Variable>("pos", ast::StorageClass::kNone, &ary);
  var->set_is_const(true);
  var->set_constructor(
      std::make_unique<ast::TypeConstructorExpression>(&ary, std::move(exprs)));

  ast::Module m;
  GeneratorImpl g(&m);
  ASSERT_TRUE(g.EmitProgramConstVariable(var.get())) << g.error();
  EXPECT_EQ(
      g.result(),
      "constant float pos[3] = {1.00000000f, 2.00000000f, 3.00000000f};\n");
}

TEST_F(MslGeneratorImplTest, Emit_SpecConstant) {
  ast::type::F32Type f32;

  ast::VariableDecorationList decos;
  decos.push_back(std::make_unique<ast::ConstantIdDecoration>(23));

  auto var = std::make_unique<ast::DecoratedVariable>(
      std::make_unique<ast::Variable>("pos", ast::StorageClass::kNone, &f32));
  var->set_decorations(std::move(decos));
  var->set_is_const(true);
  var->set_constructor(std::make_unique<ast::ScalarConstructorExpression>(
      std::make_unique<ast::FloatLiteral>(&f32, 3.0f)));

  ast::Module m;
  GeneratorImpl g(&m);
  ASSERT_TRUE(g.EmitProgramConstVariable(var.get())) << g.error();
  EXPECT_EQ(g.result(), "constant float pos [[function_constant(23)]];\n");
}

}  // namespace
}  // namespace msl
}  // namespace writer
}  // namespace tint