// 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 "gmock/gmock.h"
#include "src/ast/array_accessor_expression.h"
#include "src/ast/assignment_statement.h"
#include "src/ast/float_literal.h"
#include "src/ast/identifier_expression.h"
#include "src/ast/member_accessor_expression.h"
#include "src/ast/scalar_constructor_expression.h"
#include "src/ast/sint_literal.h"
#include "src/ast/struct.h"
#include "src/ast/struct_member.h"
#include "src/ast/type/f32_type.h"
#include "src/ast/type/i32_type.h"
#include "src/ast/type/struct_type.h"
#include "src/ast/type/vector_type.h"
#include "src/ast/type_constructor_expression.h"
#include "src/type_determiner.h"
#include "src/writer/spirv/builder.h"
#include "src/writer/spirv/spv_dump.h"
#include "src/writer/spirv/test_helper.h"

namespace tint {
namespace writer {
namespace spirv {
namespace {

using BuilderTest = TestHelper;

TEST_F(BuilderTest, Assign_Var) {
  auto* v = Var("var", ast::StorageClass::kOutput, ty.f32);

  auto* assign = create<ast::AssignmentStatement>(Expr("var"), Expr(1.f));
  td.RegisterVariableForTesting(v);

  ASSERT_TRUE(td.DetermineResultType(assign)) << td.error();

  b.push_function(Function{});
  EXPECT_TRUE(b.GenerateGlobalVariable(v)) << b.error();
  ASSERT_FALSE(b.has_error()) << b.error();

  EXPECT_TRUE(b.GenerateAssignStatement(assign)) << b.error();
  EXPECT_FALSE(b.has_error());

  EXPECT_EQ(DumpInstructions(b.types()), R"(%3 = OpTypeFloat 32
%2 = OpTypePointer Output %3
%4 = OpConstantNull %3
%1 = OpVariable %2 Output %4
%5 = OpConstant %3 1
)");

  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()), R"(OpStore %1 %5
)");
}

TEST_F(BuilderTest, Assign_Var_OutsideFunction_IsError) {
  auto* v = Var("var", ast::StorageClass::kOutput, ty.f32);

  auto* assign = create<ast::AssignmentStatement>(Expr("var"), Expr(1.f));
  td.RegisterVariableForTesting(v);

  ASSERT_TRUE(td.DetermineResultType(assign)) << td.error();

  EXPECT_TRUE(b.GenerateGlobalVariable(v)) << b.error();
  ASSERT_FALSE(b.has_error()) << b.error();

  EXPECT_FALSE(b.GenerateAssignStatement(assign)) << b.error();
  EXPECT_TRUE(b.has_error());
  EXPECT_EQ(
      b.error(),
      "Internal error: trying to add SPIR-V instruction 62 outside a function");
}

TEST_F(BuilderTest, Assign_Var_ZeroConstructor) {
  auto* v = Var("var", ast::StorageClass::kOutput, ty.vec3<f32>());

  auto* val = vec3<f32>();
  auto* assign = create<ast::AssignmentStatement>(Expr("var"), val);

  td.RegisterVariableForTesting(v);

  ASSERT_TRUE(td.DetermineResultType(assign)) << td.error();

  b.push_function(Function{});
  EXPECT_TRUE(b.GenerateGlobalVariable(v)) << b.error();
  ASSERT_FALSE(b.has_error()) << b.error();

  EXPECT_TRUE(b.GenerateAssignStatement(assign)) << b.error();
  EXPECT_FALSE(b.has_error());

  EXPECT_EQ(DumpInstructions(b.types()), R"(%4 = OpTypeFloat 32
%3 = OpTypeVector %4 3
%2 = OpTypePointer Output %3
%5 = OpConstantNull %3
%1 = OpVariable %2 Output %5
)");

  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()), R"(OpStore %1 %5
)");
}

TEST_F(BuilderTest, Assign_Var_Complex_ConstructorWithExtract) {
  auto* init = vec3<f32>(vec2<f32>(1.f, 2.f), 3.f);

  auto* v = Var("var", ast::StorageClass::kOutput, ty.vec3<f32>());
  auto* assign = create<ast::AssignmentStatement>(Expr("var"), init);

  td.RegisterVariableForTesting(v);
  ASSERT_TRUE(td.DetermineResultType(assign)) << td.error();

  b.push_function(Function{});
  EXPECT_TRUE(b.GenerateGlobalVariable(v)) << b.error();
  ASSERT_FALSE(b.has_error()) << b.error();

  EXPECT_TRUE(b.GenerateAssignStatement(assign)) << b.error();
  EXPECT_FALSE(b.has_error());

  EXPECT_EQ(DumpInstructions(b.types()), R"(%4 = OpTypeFloat 32
%3 = OpTypeVector %4 3
%2 = OpTypePointer Output %3
%5 = OpConstantNull %3
%1 = OpVariable %2 Output %5
%6 = OpTypeVector %4 2
%7 = OpConstant %4 1
%8 = OpConstant %4 2
%9 = OpConstantComposite %6 %7 %8
%12 = OpConstant %4 3
)");
  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()),
            R"(%10 = OpCompositeExtract %4 %9 0
%11 = OpCompositeExtract %4 %9 1
%13 = OpCompositeConstruct %3 %10 %11 %12
OpStore %1 %13
)");
}

TEST_F(BuilderTest, Assign_Var_Complex_Constructor) {
  auto* init = vec3<f32>(1.f, 2.f, 3.f);

  auto* v = Var("var", ast::StorageClass::kOutput, ty.vec3<f32>());
  auto* assign = create<ast::AssignmentStatement>(Expr("var"), init);

  td.RegisterVariableForTesting(v);
  ASSERT_TRUE(td.DetermineResultType(assign)) << td.error();

  b.push_function(Function{});
  EXPECT_TRUE(b.GenerateGlobalVariable(v)) << b.error();
  ASSERT_FALSE(b.has_error()) << b.error();

  EXPECT_TRUE(b.GenerateAssignStatement(assign)) << b.error();
  EXPECT_FALSE(b.has_error());

  EXPECT_EQ(DumpInstructions(b.types()), R"(%4 = OpTypeFloat 32
%3 = OpTypeVector %4 3
%2 = OpTypePointer Output %3
%5 = OpConstantNull %3
%1 = OpVariable %2 Output %5
%6 = OpConstant %4 1
%7 = OpConstant %4 2
%8 = OpConstant %4 3
%9 = OpConstantComposite %3 %6 %7 %8
)");
  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()), R"(OpStore %1 %9
)");
}

TEST_F(BuilderTest, Assign_StructMember) {
  // my_struct {
  //   a : f32
  //   b : f32
  // }
  // var ident : my_struct
  // ident.b = 4.0;

  auto* s = create<ast::Struct>(
      ast::StructMemberList{Member("a", ty.f32), Member("b", ty.f32)},
      ast::StructDecorationList{});

  auto* s_type = ty.struct_("my_struct", s);
  auto* v = Var("ident", ast::StorageClass::kFunction, s_type);

  auto* assign =
      create<ast::AssignmentStatement>(MemberAccessor("ident", "b"), Expr(4.f));
  td.RegisterVariableForTesting(v);

  ASSERT_TRUE(td.DetermineResultType(assign)) << td.error();

  b.push_function(Function{});
  EXPECT_TRUE(b.GenerateGlobalVariable(v)) << b.error();
  ASSERT_FALSE(b.has_error()) << b.error();

  EXPECT_TRUE(b.GenerateAssignStatement(assign)) << b.error();
  EXPECT_FALSE(b.has_error());

  EXPECT_EQ(DumpInstructions(b.types()), R"(%4 = OpTypeFloat 32
%3 = OpTypeStruct %4 %4
%2 = OpTypePointer Function %3
%1 = OpVariable %2 Function
%5 = OpTypeInt 32 0
%6 = OpConstant %5 1
%7 = OpTypePointer Function %4
%9 = OpConstant %4 4
)");

  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()),
            R"(%8 = OpAccessChain %7 %1 %6
OpStore %8 %9
)");
}

TEST_F(BuilderTest, Assign_Vector) {
  auto* v = Var("var", ast::StorageClass::kOutput, ty.vec3<f32>());

  auto* val = vec3<f32>(1.f, 1.f, 3.f);

  auto* assign = create<ast::AssignmentStatement>(Expr("var"), val);
  td.RegisterVariableForTesting(v);

  ASSERT_TRUE(td.DetermineResultType(assign)) << td.error();

  b.push_function(Function{});
  EXPECT_TRUE(b.GenerateGlobalVariable(v)) << b.error();
  ASSERT_FALSE(b.has_error()) << b.error();

  EXPECT_TRUE(b.GenerateAssignStatement(assign)) << b.error();
  EXPECT_FALSE(b.has_error());

  EXPECT_EQ(DumpInstructions(b.types()), R"(%4 = OpTypeFloat 32
%3 = OpTypeVector %4 3
%2 = OpTypePointer Output %3
%5 = OpConstantNull %3
%1 = OpVariable %2 Output %5
%6 = OpConstant %4 1
%7 = OpConstant %4 3
%8 = OpConstantComposite %3 %6 %6 %7
)");

  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()), R"(OpStore %1 %8
)");
}

TEST_F(BuilderTest, Assign_Vector_MemberByName) {
  // var.y = 1

  auto* v = Var("var", ast::StorageClass::kOutput, ty.vec3<f32>());

  auto* assign =
      create<ast::AssignmentStatement>(MemberAccessor("var", "y"), Expr(1.f));
  td.RegisterVariableForTesting(v);

  ASSERT_TRUE(td.DetermineResultType(assign)) << td.error();

  b.push_function(Function{});
  EXPECT_TRUE(b.GenerateGlobalVariable(v)) << b.error();
  ASSERT_FALSE(b.has_error()) << b.error();

  EXPECT_TRUE(b.GenerateAssignStatement(assign)) << b.error();
  EXPECT_FALSE(b.has_error());

  EXPECT_EQ(DumpInstructions(b.types()), R"(%4 = OpTypeFloat 32
%3 = OpTypeVector %4 3
%2 = OpTypePointer Output %3
%5 = OpConstantNull %3
%1 = OpVariable %2 Output %5
%6 = OpTypeInt 32 0
%7 = OpConstant %6 1
%8 = OpTypePointer Output %4
%10 = OpConstant %4 1
)");

  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()),
            R"(%9 = OpAccessChain %8 %1 %7
OpStore %9 %10
)");
}

TEST_F(BuilderTest, Assign_Vector_MemberByIndex) {
  // var[1] = 1

  auto* v = Var("var", ast::StorageClass::kOutput, ty.vec3<f32>());

  auto* assign =
      create<ast::AssignmentStatement>(IndexAccessor("var", 1), Expr(1.f));
  td.RegisterVariableForTesting(v);

  ASSERT_TRUE(td.DetermineResultType(assign)) << td.error();

  b.push_function(Function{});
  EXPECT_TRUE(b.GenerateGlobalVariable(v)) << b.error();
  ASSERT_FALSE(b.has_error()) << b.error();

  EXPECT_TRUE(b.GenerateAssignStatement(assign)) << b.error();
  EXPECT_FALSE(b.has_error());

  EXPECT_EQ(DumpInstructions(b.types()), R"(%4 = OpTypeFloat 32
%3 = OpTypeVector %4 3
%2 = OpTypePointer Output %3
%5 = OpConstantNull %3
%1 = OpVariable %2 Output %5
%6 = OpTypeInt 32 1
%7 = OpConstant %6 1
%8 = OpTypePointer Output %4
%10 = OpConstant %4 1
)");

  EXPECT_EQ(DumpInstructions(b.functions()[0].instructions()),
            R"(%9 = OpAccessChain %8 %1 %7
OpStore %9 %10
)");
}

}  // namespace
}  // namespace spirv
}  // namespace writer
}  // namespace tint