// 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 "src/ast/constant_id_decoration.h"
#include "src/ast/float_literal.h"
#include "src/ast/scalar_constructor_expression.h"
#include "src/ast/type_constructor_expression.h"
#include "src/ast/variable.h"
#include "src/program.h"
#include "src/type/array_type.h"
#include "src/type/f32_type.h"
#include "src/writer/hlsl/test_helper.h"

namespace tint {
namespace writer {
namespace hlsl {
namespace {

using HlslGeneratorImplTest_ModuleConstant = TestHelper;

TEST_F(HlslGeneratorImplTest_ModuleConstant, Emit_ModuleConstant) {
  auto* var =
      Const("pos", ast::StorageClass::kNone, ty.array<f32, 3>(),
            array<f32, 3>(1.f, 2.f, 3.f), ast::VariableDecorationList{});

  GeneratorImpl& gen = Build();

  ASSERT_TRUE(gen.EmitProgramConstVariable(out, var)) << gen.error();
  EXPECT_EQ(result(), "static const float pos[3] = {1.0f, 2.0f, 3.0f};\n");
}

TEST_F(HlslGeneratorImplTest_ModuleConstant, Emit_SpecConstant) {
  auto* var = Const("pos", ast::StorageClass::kNone, ty.f32(), Expr(3.0f),
                    ast::VariableDecorationList{
                        create<ast::ConstantIdDecoration>(23),
                    });

  GeneratorImpl& gen = Build();

  ASSERT_TRUE(gen.EmitProgramConstVariable(out, var)) << gen.error();
  EXPECT_EQ(result(), R"(#ifndef WGSL_SPEC_CONSTANT_23
#define WGSL_SPEC_CONSTANT_23 3.0f
#endif
static const float pos = WGSL_SPEC_CONSTANT_23;
#undef WGSL_SPEC_CONSTANT_23
)");
}

TEST_F(HlslGeneratorImplTest_ModuleConstant, Emit_SpecConstant_NoConstructor) {
  auto* var = Const("pos", ast::StorageClass::kNone, ty.f32(), nullptr,
                    ast::VariableDecorationList{
                        create<ast::ConstantIdDecoration>(23),
                    });

  GeneratorImpl& gen = Build();

  ASSERT_TRUE(gen.EmitProgramConstVariable(out, var)) << gen.error();
  EXPECT_EQ(result(), R"(#ifndef WGSL_SPEC_CONSTANT_23
#error spec constant required for constant id 23
#endif
static const float pos = WGSL_SPEC_CONSTANT_23;
#undef WGSL_SPEC_CONSTANT_23
)");
}

}  // namespace
}  // namespace hlsl
}  // namespace writer
}  // namespace tint