// Copyright 2021 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 "src/tint/writer/glsl/test_helper.h"

#include "gmock/gmock.h"

namespace tint::writer::glsl {
namespace {

using GlslGeneratorImplTest_If = TestHelper;

TEST_F(GlslGeneratorImplTest_If, Emit_If) {
    GlobalVar("cond", ty.bool_(), builtin::AddressSpace::kPrivate);

    auto* cond = Expr("cond");
    auto* body = Block(Return());
    auto* i = If(cond, body);
    WrapInFunction(i);

    GeneratorImpl& gen = Build();

    gen.increment_indent();
    gen.EmitStatement(i);
    EXPECT_THAT(gen.Diagnostics(), testing::IsEmpty());
    EXPECT_EQ(gen.result(), R"(  if (cond) {
    return;
  }
)");
}

TEST_F(GlslGeneratorImplTest_If, Emit_IfWithElseIf) {
    GlobalVar("cond", ty.bool_(), builtin::AddressSpace::kPrivate);
    GlobalVar("else_cond", ty.bool_(), builtin::AddressSpace::kPrivate);

    auto* else_cond = Expr("else_cond");
    auto* else_body = Block(Return());

    auto* cond = Expr("cond");
    auto* body = Block(Return());
    auto* i = If(cond, body, Else(If(else_cond, else_body)));
    WrapInFunction(i);

    GeneratorImpl& gen = Build();

    gen.increment_indent();
    gen.EmitStatement(i);
    EXPECT_THAT(gen.Diagnostics(), testing::IsEmpty());
    EXPECT_EQ(gen.result(), R"(  if (cond) {
    return;
  } else {
    if (else_cond) {
      return;
    }
  }
)");
}

TEST_F(GlslGeneratorImplTest_If, Emit_IfWithElse) {
    GlobalVar("cond", ty.bool_(), builtin::AddressSpace::kPrivate);

    auto* else_body = Block(Return());

    auto* cond = Expr("cond");
    auto* body = Block(Return());
    auto* i = If(cond, body, Else(else_body));
    WrapInFunction(i);

    GeneratorImpl& gen = Build();

    gen.increment_indent();
    gen.EmitStatement(i);
    EXPECT_THAT(gen.Diagnostics(), testing::IsEmpty());
    EXPECT_EQ(gen.result(), R"(  if (cond) {
    return;
  } else {
    return;
  }
)");
}

TEST_F(GlslGeneratorImplTest_If, Emit_IfWithMultiple) {
    GlobalVar("cond", ty.bool_(), builtin::AddressSpace::kPrivate);
    GlobalVar("else_cond", ty.bool_(), builtin::AddressSpace::kPrivate);

    auto* else_cond = Expr("else_cond");
    auto* else_body = Block(Return());
    auto* else_body_2 = Block(Return());

    auto* cond = Expr("cond");
    auto* body = Block(Return());
    auto* i = If(cond, body, Else(If(else_cond, else_body, Else(else_body_2))));
    WrapInFunction(i);

    GeneratorImpl& gen = Build();

    gen.increment_indent();
    gen.EmitStatement(i);
    EXPECT_THAT(gen.Diagnostics(), testing::IsEmpty());
    EXPECT_EQ(gen.result(), R"(  if (cond) {
    return;
  } else {
    if (else_cond) {
      return;
    } else {
      return;
    }
  }
)");
}

}  // namespace
}  // namespace tint::writer::glsl