// 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/identifier_expression.h"
#include "src/ast/module.h"
#include "src/ast/type/array_type.h"
#include "src/ast/type/f32_type.h"
#include "src/ast/type/matrix_type.h"
#include "src/ast/type/vector_type.h"
#include "src/ast/variable.h"
#include "src/ast/variable_decl_statement.h"
#include "src/writer/hlsl/test_helper.h"

namespace tint {
namespace writer {
namespace hlsl {
namespace {

using HlslGeneratorImplTest_VariableDecl = TestHelper;

TEST_F(HlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement) {
  ast::type::F32 f32;
  auto* var =
      create<ast::Variable>(Source{}, "a", ast::StorageClass::kNone, &f32);

  ast::VariableDeclStatement stmt(var);
  gen.increment_indent();

  ASSERT_TRUE(gen.EmitStatement(out, &stmt)) << gen.error();
  EXPECT_EQ(result(), "  float a;\n");
}

TEST_F(HlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement_Const) {
  ast::type::F32 f32;
  auto* var =
      create<ast::Variable>(Source{}, "a", ast::StorageClass::kNone, &f32);
  var->set_is_const(true);

  ast::VariableDeclStatement stmt(var);
  gen.increment_indent();

  ASSERT_TRUE(gen.EmitStatement(out, &stmt)) << gen.error();
  EXPECT_EQ(result(), "  const float a;\n");
}

TEST_F(HlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement_Array) {
  ast::type::F32 f32;
  ast::type::Array ary(&f32, 5, ast::ArrayDecorationList{});

  auto* var =
      create<ast::Variable>(Source{}, "a", ast::StorageClass::kNone, &ary);

  ast::VariableDeclStatement stmt(var);
  gen.increment_indent();

  ASSERT_TRUE(gen.EmitStatement(out, &stmt)) << gen.error();
  EXPECT_EQ(result(), "  float a[5];\n");
}

TEST_F(HlslGeneratorImplTest_VariableDecl,
       Emit_VariableDeclStatement_Function) {
  ast::type::F32 f32;
  auto* var =
      create<ast::Variable>(Source{}, "a", ast::StorageClass::kFunction, &f32);

  ast::VariableDeclStatement stmt(var);
  gen.increment_indent();

  ASSERT_TRUE(gen.EmitStatement(out, &stmt)) << gen.error();
  EXPECT_EQ(result(), "  float a;\n");
}

TEST_F(HlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement_Private) {
  ast::type::F32 f32;
  auto* var =
      create<ast::Variable>(Source{}, "a", ast::StorageClass::kPrivate, &f32);

  ast::VariableDeclStatement stmt(var);
  gen.increment_indent();

  ASSERT_TRUE(gen.EmitStatement(out, &stmt)) << gen.error();
  EXPECT_EQ(result(), "  float a;\n");
}

TEST_F(HlslGeneratorImplTest_VariableDecl,
       Emit_VariableDeclStatement_Initializer_Private) {
  auto* ident = create<ast::IdentifierExpression>("initializer");

  ast::type::F32 f32;
  auto* var =
      create<ast::Variable>(Source{}, "a", ast::StorageClass::kNone, &f32);
  var->set_constructor(ident);

  ast::VariableDeclStatement stmt(var);
  ASSERT_TRUE(gen.EmitStatement(out, &stmt)) << gen.error();
  EXPECT_EQ(result(), R"(float a = initializer;
)");
}

TEST_F(HlslGeneratorImplTest_VariableDecl,
       Emit_VariableDeclStatement_Initializer_ZeroVec) {
  ast::type::F32 f32;
  ast::type::Vector vec(&f32, 3);

  ast::ExpressionList values;
  auto* zero_vec = create<ast::TypeConstructorExpression>(&vec, values);

  auto* var =
      create<ast::Variable>(Source{}, "a", ast::StorageClass::kNone, &vec);
  var->set_constructor(zero_vec);

  ast::VariableDeclStatement stmt(var);
  ASSERT_TRUE(gen.EmitStatement(out, &stmt)) << gen.error();
  EXPECT_EQ(result(), R"(float3 a = float3(0.0f);
)");
}

TEST_F(HlslGeneratorImplTest_VariableDecl,
       Emit_VariableDeclStatement_Initializer_ZeroMat) {
  ast::type::F32 f32;
  ast::type::Matrix mat(&f32, 3, 2);

  ast::ExpressionList values;
  auto* zero_mat = create<ast::TypeConstructorExpression>(&mat, values);

  auto* var =
      create<ast::Variable>(Source{}, "a", ast::StorageClass::kNone, &mat);
  var->set_constructor(zero_mat);

  ast::VariableDeclStatement stmt(var);
  ASSERT_TRUE(gen.EmitStatement(out, &stmt)) << gen.error();
  EXPECT_EQ(result(),
            R"(float3x2 a = float3x2(0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f);
)");
}

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