// 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 "gtest/gtest.h"
#include "spirv/unified1/GLSL.std.450.h"
#include "src/ast/array_accessor_expression.h"
#include "src/ast/assignment_statement.h"
#include "src/ast/binary_expression.h"
#include "src/ast/bool_literal.h"
#include "src/ast/break_statement.h"
#include "src/ast/call_expression.h"
#include "src/ast/call_statement.h"
#include "src/ast/case_statement.h"
#include "src/ast/continue_statement.h"
#include "src/ast/else_statement.h"
#include "src/ast/float_literal.h"
#include "src/ast/identifier_expression.h"
#include "src/ast/if_statement.h"
#include "src/ast/int_literal.h"
#include "src/ast/loop_statement.h"
#include "src/ast/member_accessor_expression.h"
#include "src/ast/pipeline_stage.h"
#include "src/ast/return_statement.h"
#include "src/ast/scalar_constructor_expression.h"
#include "src/ast/sint_literal.h"
#include "src/ast/stage_decoration.h"
#include "src/ast/struct.h"
#include "src/ast/struct_member.h"
#include "src/ast/switch_statement.h"
#include "src/ast/type/alias_type.h"
#include "src/ast/type/array_type.h"
#include "src/ast/type/bool_type.h"
#include "src/ast/type/f32_type.h"
#include "src/ast/type/i32_type.h"
#include "src/ast/type/matrix_type.h"
#include "src/ast/type/pointer_type.h"
#include "src/ast/type/struct_type.h"
#include "src/ast/type/vector_type.h"
#include "src/ast/type/void_type.h"
#include "src/ast/type_constructor_expression.h"
#include "src/ast/variable.h"
#include "src/ast/variable_decl_statement.h"
#include "src/type_determiner.h"
#include "src/validator/validator_impl.h"
#include "src/validator/validator_test_helper.h"

namespace tint {
namespace {

class ValidatorTest : public ValidatorTestHelper, public testing::Test {};

TEST_F(ValidatorTest, DISABLED_AssignToScalar_Fail) {
  // 1 = my_var;

  auto* lhs = Expr(1);
  auto* rhs = Expr("my_var");
  SetSource(Source{Source::Location{12, 34}});
  create<ast::AssignmentStatement>(lhs, rhs);

  // TODO(sarahM0): Invalidate assignment to scalar.
  ASSERT_TRUE(v()->has_error());
  // TODO(sarahM0): figure out what should be the error number.
  EXPECT_EQ(v()->error(), "12:34 v-000x: invalid assignment");
}

TEST_F(ValidatorTest, UsingUndefinedVariable_Fail) {
  // b = 2;

  SetSource(Source{Source::Location{12, 34}});
  auto* lhs = Expr("b");
  auto* rhs = Expr(2);
  auto* assign = create<ast::AssignmentStatement>(lhs, rhs);

  EXPECT_FALSE(td()->DetermineResultType(assign));
  EXPECT_EQ(td()->error(),
            "12:34: v-0006: identifier must be declared before use: b");
}

TEST_F(ValidatorTest, UsingUndefinedVariableInBlockStatement_Fail) {
  // {
  //  b = 2;
  // }

  SetSource(Source{Source::Location{12, 34}});
  auto* lhs = Expr("b");
  auto* rhs = Expr(2);

  auto* body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::AssignmentStatement>(lhs, rhs),
  });

  EXPECT_FALSE(td()->DetermineStatements(body));
  EXPECT_EQ(td()->error(),
            "12:34: v-0006: identifier must be declared before use: b");
}

TEST_F(ValidatorTest, AssignCompatibleTypes_Pass) {
  // var a :i32 = 2;
  // a = 2
  auto* var = Var("a", ast::StorageClass::kNone, ty.i32, Expr(2),
                  ast::VariableDecorationList{});

  auto* lhs = Expr("a");
  auto* rhs = Expr(2);

  auto* assign = create<ast::AssignmentStatement>(
      Source{Source::Location{12, 34}}, lhs, rhs);
  td()->RegisterVariableForTesting(var);
  EXPECT_TRUE(td()->DetermineResultType(assign)) << td()->error();
  ASSERT_NE(lhs->result_type(), nullptr);
  ASSERT_NE(rhs->result_type(), nullptr);
  EXPECT_TRUE(v()->ValidateResultTypes(assign));
}

TEST_F(ValidatorTest, AssignIncompatibleTypes_Fail) {
  // {
  //  var a :i32 = 2;
  //  a = 2.3;
  // }

  auto* var = Var("a", ast::StorageClass::kNone, ty.i32, Expr(2),
                  ast::VariableDecorationList{});

  auto* lhs = Expr("a");
  auto* rhs = Expr(2.3f);

  auto* assign = create<ast::AssignmentStatement>(
      Source{Source::Location{12, 34}}, lhs, rhs);
  td()->RegisterVariableForTesting(var);
  EXPECT_TRUE(td()->DetermineResultType(assign)) << td()->error();
  ASSERT_NE(lhs->result_type(), nullptr);
  ASSERT_NE(rhs->result_type(), nullptr);

  EXPECT_FALSE(v()->ValidateResultTypes(assign));
  ASSERT_TRUE(v()->has_error());
  // TODO(sarahM0): figure out what should be the error number.
  EXPECT_EQ(v()->error(),
            "12:34 v-000x: invalid assignment of '__i32' to '__f32'");
}

TEST_F(ValidatorTest, AssignCompatibleTypesInBlockStatement_Pass) {
  // {
  //  var a :i32 = 2;
  //  a = 2
  // }
  auto* var = Var("a", ast::StorageClass::kNone, ty.i32, Expr(2),
                  ast::VariableDecorationList{});

  auto* lhs = Expr("a");
  auto* rhs = Expr(2);

  auto* body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::VariableDeclStatement>(var),
      create<ast::AssignmentStatement>(Source{Source::Location{12, 34}}, lhs,
                                       rhs),
  });

  EXPECT_TRUE(td()->DetermineStatements(body)) << td()->error();
  ASSERT_NE(lhs->result_type(), nullptr);
  ASSERT_NE(rhs->result_type(), nullptr);

  EXPECT_TRUE(v()->ValidateStatements(body)) << v()->error();
}

TEST_F(ValidatorTest, AssignIncompatibleTypesInBlockStatement_Fail) {
  // {
  //  var a :i32 = 2;
  //  a = 2.3;
  // }

  auto* var = Var("a", ast::StorageClass::kNone, ty.i32, Expr(2),
                  ast::VariableDecorationList{});

  auto* lhs = Expr("a");
  auto* rhs = Expr(2.3f);

  auto* block = create<ast::BlockStatement>(ast::StatementList{
      create<ast::VariableDeclStatement>(var),
      create<ast::AssignmentStatement>(Source{Source::Location{12, 34}}, lhs,
                                       rhs),
  });

  EXPECT_TRUE(td()->DetermineStatements(block)) << td()->error();
  ASSERT_NE(lhs->result_type(), nullptr);
  ASSERT_NE(rhs->result_type(), nullptr);

  EXPECT_FALSE(v()->ValidateStatements(block));
  ASSERT_TRUE(v()->has_error());
  // TODO(sarahM0): figure out what should be the error number.
  EXPECT_EQ(v()->error(),
            "12:34 v-000x: invalid assignment of '__i32' to '__f32'");
}

TEST_F(ValidatorTest, GlobalVariableWithStorageClass_Pass) {
  // var<in> gloabl_var: f32;
  mod->AddGlobalVariable(Var(Source{Source::Location{12, 34}}, "global_var",
                             ast::StorageClass::kInput, ty.f32, nullptr,
                             ast::VariableDecorationList{}));
  EXPECT_TRUE(v()->ValidateGlobalVariables(mod->global_variables()))
      << v()->error();
}

TEST_F(ValidatorTest, GlobalVariableNoStorageClass_Fail) {
  // var gloabl_var: f32;
  mod->AddGlobalVariable(Var(Source{Source::Location{12, 34}}, "global_var",
                             ast::StorageClass::kNone, ty.f32, nullptr,
                             ast::VariableDecorationList{}));
  EXPECT_TRUE(td()->Determine()) << td()->error();
  EXPECT_FALSE(v()->Validate());
  EXPECT_EQ(v()->error(),
            "12:34 v-0022: global variables must have a storage class");
}

TEST_F(ValidatorTest, GlobalConstantWithStorageClass_Fail) {
  // const<in> gloabl_var: f32;
  mod->AddGlobalVariable(Const(Source{Source::Location{12, 34}}, "global_var",
                               ast::StorageClass::kInput, ty.f32, nullptr,
                               ast::VariableDecorationList{}));
  EXPECT_TRUE(td()->Determine()) << td()->error();
  EXPECT_FALSE(v()->Validate());
  EXPECT_EQ(
      v()->error(),
      "12:34 v-global01: global constants shouldn't have a storage class");
}

TEST_F(ValidatorTest, GlobalConstNoStorageClass_Pass) {
  // const gloabl_var: f32;
  mod->AddGlobalVariable(Const(Source{Source::Location{12, 34}}, "global_var",
                               ast::StorageClass::kNone, ty.f32, nullptr,
                               ast::VariableDecorationList{}));
  EXPECT_TRUE(td()->Determine()) << td()->error();
  EXPECT_FALSE(v()->Validate()) << v()->error();
}

TEST_F(ValidatorTest, UsingUndefinedVariableGlobalVariable_Fail) {
  // var global_var: f32 = 2.1;
  // fn my_func() -> f32 {
  //   not_global_var = 3.14f;
  // }
  mod->AddGlobalVariable(Var("global_var", ast::StorageClass::kPrivate, ty.f32,
                             Expr(2.1f), ast::VariableDecorationList{}));

  SetSource(Source{Source::Location{12, 34}});
  auto* lhs = Expr("not_global_var");
  auto* rhs = Expr(3.14f);

  auto* func = Func("my_func", ast::VariableList{}, ty.f32,
                    ast::StatementList{
                        create<ast::AssignmentStatement>(
                            Source{Source::Location{12, 34}}, lhs, rhs),
                    },
                    ast::FunctionDecorationList{});
  mod->AddFunction(func);

  EXPECT_FALSE(v()->Validate());
  EXPECT_EQ(v()->error(), "12:34 v-0006: 'not_global_var' is not declared");
}

TEST_F(ValidatorTest, UsingUndefinedVariableGlobalVariable_Pass) {
  // var global_var: f32 = 2.1;
  // fn my_func() -> void {
  //   global_var = 3.14;
  //   return;
  // }

  mod->AddGlobalVariable(Var("global_var", ast::StorageClass::kPrivate, ty.f32,
                             Expr(2.1f), ast::VariableDecorationList{}));

  auto* func = Func(
      "my_func", ast::VariableList{}, ty.void_,
      ast::StatementList{
          create<ast::AssignmentStatement>(Source{Source::Location{12, 34}},
                                           Expr("global_var"), Expr(3.14f)),
          create<ast::ReturnStatement>(),
      },
      ast::FunctionDecorationList{
          create<ast::StageDecoration>(ast::PipelineStage::kVertex),
      });
  mod->AddFunction(func);

  EXPECT_TRUE(td()->Determine()) << td()->error();
  EXPECT_TRUE(v()->Validate()) << v()->error();
}

TEST_F(ValidatorTest, UsingUndefinedVariableInnerScope_Fail) {
  // {
  //   if (true) { var a : f32 = 2.0; }
  //   a = 3.14;
  // }
  auto* var = Var("a", ast::StorageClass::kNone, ty.f32, Expr(2.0f),
                  ast::VariableDecorationList{});

  auto* cond = Expr(true);
  auto* body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::VariableDeclStatement>(var),
  });

  SetSource(Source{Source::Location{12, 34}});
  auto* lhs = Expr("a");
  auto* rhs = Expr(3.14f);

  auto* outer_body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::IfStatement>(cond, body, ast::ElseStatementList{}),
      create<ast::AssignmentStatement>(Source{Source::Location{12, 34}}, lhs,
                                       rhs),
  });

  EXPECT_TRUE(td()->DetermineStatements(outer_body)) << td()->error();
  ASSERT_NE(lhs->result_type(), nullptr);
  ASSERT_NE(rhs->result_type(), nullptr);
  EXPECT_FALSE(v()->ValidateStatements(outer_body));
  EXPECT_EQ(v()->error(), "12:34 v-0006: 'a' is not declared");
}

TEST_F(ValidatorTest, UsingUndefinedVariableOuterScope_Pass) {
  // {
  //   var a : f32 = 2.0;
  //   if (true) { a = 3.14; }
  // }
  auto* var = Var("a", ast::StorageClass::kNone, ty.f32, Expr(2.0f),
                  ast::VariableDecorationList{});

  SetSource(Source{Source::Location{12, 34}});
  auto* lhs = Expr("a");
  auto* rhs = Expr(3.14f);

  auto* cond = Expr(true);
  auto* body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::AssignmentStatement>(Source{Source::Location{12, 34}}, lhs,
                                       rhs),
  });

  auto* outer_body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::VariableDeclStatement>(var),
      create<ast::IfStatement>(cond, body, ast::ElseStatementList{}),
  });

  EXPECT_TRUE(td()->DetermineStatements(outer_body)) << td()->error();
  ASSERT_NE(lhs->result_type(), nullptr);
  ASSERT_NE(rhs->result_type(), nullptr);
  EXPECT_TRUE(v()->ValidateStatements(outer_body)) << v()->error();
}

TEST_F(ValidatorTest, GlobalVariableUnique_Pass) {
  // var global_var0 : f32 = 0.1;
  // var global_var1 : i32 = 0;
  auto* var0 = Var("global_var0", ast::StorageClass::kPrivate, ty.f32,
                   Expr(0.1f), ast::VariableDecorationList{});
  mod->AddGlobalVariable(var0);

  auto* var1 = Var(Source{Source::Location{12, 34}}, "global_var1",
                   ast::StorageClass::kPrivate, ty.f32, Expr(0),
                   ast::VariableDecorationList{});
  mod->AddGlobalVariable(var1);

  EXPECT_TRUE(v()->ValidateGlobalVariables(mod->global_variables()))
      << v()->error();
}

TEST_F(ValidatorTest, GlobalVariableNotUnique_Fail) {
  // var global_var : f32 = 0.1;
  // var global_var : i32 = 0;
  auto* var0 = Var("global_var", ast::StorageClass::kPrivate, ty.f32,
                   Expr(0.1f), ast::VariableDecorationList{});
  mod->AddGlobalVariable(var0);

  auto* var1 = Var(Source{Source::Location{12, 34}}, "global_var",
                   ast::StorageClass::kPrivate, ty.i32, Expr(0),
                   ast::VariableDecorationList{});
  mod->AddGlobalVariable(var1);

  EXPECT_FALSE(v()->ValidateGlobalVariables(mod->global_variables()));
  EXPECT_EQ(v()->error(),
            "12:34 v-0011: redeclared global identifier 'global_var'");
}

TEST_F(ValidatorTest, AssignToConstant_Fail) {
  // {
  //  const a :i32 = 2;
  //  a = 2
  // }
  auto* var = Const("a", ast::StorageClass::kNone, ty.i32, Expr(2),
                    ast::VariableDecorationList{});

  auto* lhs = Expr("a");
  auto* rhs = Expr(2);

  auto* body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::VariableDeclStatement>(var),
      create<ast::AssignmentStatement>(Source{Source::Location{12, 34}}, lhs,
                                       rhs),
  });

  EXPECT_TRUE(td()->DetermineStatements(body)) << td()->error();
  ASSERT_NE(lhs->result_type(), nullptr);
  ASSERT_NE(rhs->result_type(), nullptr);

  EXPECT_FALSE(v()->ValidateStatements(body));
  EXPECT_EQ(v()->error(), "12:34 v-0021: cannot re-assign a constant: 'a'");
}

TEST_F(ValidatorTest, GlobalVariableFunctionVariableNotUnique_Fail) {
  // var a: f32 = 2.1;
  // fn my_func -> void {
  //   var a: f32 = 2.0;
  //   return 0;
  // }

  auto* global_var = Var("a", ast::StorageClass::kPrivate, ty.f32, Expr(2.1f),
                         ast::VariableDecorationList{});
  mod->AddGlobalVariable(global_var);

  auto* var = Var("a", ast::StorageClass::kNone, ty.f32, Expr(2.0f),
                  ast::VariableDecorationList{});

  auto* func = Func("my_func", ast::VariableList{}, ty.void_,
                    ast::StatementList{
                        create<ast::VariableDeclStatement>(
                            Source{Source::Location{12, 34}}, var),
                    },
                    ast::FunctionDecorationList{});

  mod->AddFunction(func);

  EXPECT_TRUE(td()->Determine()) << td()->error();
  EXPECT_TRUE(td()->DetermineFunction(func)) << td()->error();
  EXPECT_FALSE(v()->Validate()) << v()->error();
  EXPECT_EQ(v()->error(), "12:34 v-0013: redeclared identifier 'a'");
}

TEST_F(ValidatorTest, RedeclaredIndentifier_Fail) {
  // fn my_func() -> void {
  //  var a :i32 = 2;
  //  var a :f21 = 2.0;
  // }
  auto* var = Var("a", ast::StorageClass::kNone, ty.i32, Expr(2),
                  ast::VariableDecorationList{});

  auto* var_a_float = Var("a", ast::StorageClass::kNone, ty.f32, Expr(0.1f),
                          ast::VariableDecorationList{});

  auto* func = Func("my_func", ast::VariableList{}, ty.void_,
                    ast::StatementList{
                        create<ast::VariableDeclStatement>(var),
                        create<ast::VariableDeclStatement>(
                            Source{Source::Location{12, 34}}, var_a_float),
                    },
                    ast::FunctionDecorationList{});

  mod->AddFunction(func);

  EXPECT_TRUE(td()->Determine()) << td()->error();
  EXPECT_TRUE(td()->DetermineFunction(func)) << td()->error();
  EXPECT_FALSE(v()->Validate());
  EXPECT_EQ(v()->error(), "12:34 v-0014: redeclared identifier 'a'");
}

TEST_F(ValidatorTest, RedeclaredIdentifierInnerScope_Pass) {
  // {
  // if (true) { var a : f32 = 2.0; }
  // var a : f32 = 3.14;
  // }
  auto* var = Var("a", ast::StorageClass::kNone, ty.f32, Expr(2.0f),
                  ast::VariableDecorationList{});

  auto* cond = Expr(true);
  auto* body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::VariableDeclStatement>(var),
  });

  auto* var_a_float = Var("a", ast::StorageClass::kNone, ty.f32, Expr(3.1f),
                          ast::VariableDecorationList{});

  auto* outer_body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::IfStatement>(cond, body, ast::ElseStatementList{}),
      create<ast::VariableDeclStatement>(Source{Source::Location{12, 34}},
                                         var_a_float),
  });

  EXPECT_TRUE(td()->DetermineStatements(outer_body)) << td()->error();
  EXPECT_TRUE(v()->ValidateStatements(outer_body)) << v()->error();
}

TEST_F(ValidatorTest, DISABLED_RedeclaredIdentifierInnerScope_False) {
  // TODO(sarahM0): remove DISABLED after implementing ValidateIfStatement
  // and it should just work
  // {
  // var a : f32 = 3.14;
  // if (true) { var a : f32 = 2.0; }
  // }
  auto* var_a_float = Var("a", ast::StorageClass::kNone, ty.f32, Expr(3.1f),
                          ast::VariableDecorationList{});

  auto* var = Var("a", ast::StorageClass::kNone, ty.f32, Expr(2.0f),
                  ast::VariableDecorationList{});

  auto* cond = Expr(true);
  auto* body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::VariableDeclStatement>(Source{Source::Location{12, 34}}, var),
  });

  auto* outer_body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::VariableDeclStatement>(var_a_float),
      create<ast::IfStatement>(cond, body, ast::ElseStatementList{}),
  });

  EXPECT_TRUE(td()->DetermineStatements(outer_body)) << td()->error();
  EXPECT_FALSE(v()->ValidateStatements(outer_body));
  EXPECT_EQ(v()->error(), "12:34 v-0014: redeclared identifier 'a'");
}

TEST_F(ValidatorTest, RedeclaredIdentifierDifferentFunctions_Pass) {
  // func0 { var a : f32 = 2.0; return; }
  // func1 { var a : f32 = 3.0; return; }
  auto* var0 = Var("a", ast::StorageClass::kNone, ty.f32, Expr(2.0f),
                   ast::VariableDecorationList{});

  auto* var1 = Var("a", ast::StorageClass::kNone, ty.void_, Expr(1.0f),
                   ast::VariableDecorationList{});

  auto* func0 = Func("func0", ast::VariableList{}, ty.void_,
                     ast::StatementList{
                         create<ast::VariableDeclStatement>(
                             Source{Source::Location{12, 34}}, var0),
                         create<ast::ReturnStatement>(),
                     },
                     ast::FunctionDecorationList{});

  auto* func1 =
      Func("func1", ast::VariableList{}, ty.void_,
           ast::StatementList{
               create<ast::VariableDeclStatement>(
                   Source{Source::Location{13, 34}}, var1),
               create<ast::ReturnStatement>(),
           },
           ast::FunctionDecorationList{
               create<ast::StageDecoration>(ast::PipelineStage::kVertex),
           });

  mod->AddFunction(func0);
  mod->AddFunction(func1);

  EXPECT_TRUE(td()->Determine()) << td()->error();
  EXPECT_TRUE(v()->Validate()) << v()->error();
}

TEST_F(ValidatorTest, VariableDeclNoConstructor_Pass) {
  // {
  // var a :i32;
  // a = 2;
  // }
  auto* var = Var("a", ast::StorageClass::kNone, ty.i32, nullptr,
                  ast::VariableDecorationList{});

  td()->RegisterVariableForTesting(var);
  auto* lhs = Expr("a");
  auto* rhs = Expr(2);

  auto* body = create<ast::BlockStatement>(ast::StatementList{
      create<ast::VariableDeclStatement>(var),
      create<ast::AssignmentStatement>(Source{Source::Location{12, 34}}, lhs,
                                       rhs),
  });

  EXPECT_TRUE(td()->DetermineStatements(body)) << td()->error();
  ASSERT_NE(lhs->result_type(), nullptr);
  ASSERT_NE(rhs->result_type(), nullptr);
  EXPECT_TRUE(v()->ValidateStatements(body)) << v()->error();
}

}  // namespace
}  // namespace tint