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#include "src/tint/lang/glsl/writer/helper_test.h"

using namespace tint::core::number_suffixes;  // NOLINT

namespace tint::glsl::writer {
namespace {

TEST_F(GlslWriterTest, If) {
    auto* func = b.ComputeFunction("main");
    b.Append(func->Block(), [&] {
        auto* if_ = b.If(true);
        b.Append(if_->True(), [&] { b.ExitIf(if_); });
        b.Return(func);
    });

    auto result = Generate();
    ASSERT_EQ(result, Success) << result.Failure().reason << output_.glsl;
    EXPECT_EQ(output_.glsl, GlslHeader() + R"(
layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
void main() {
  if (true) {
  }
}
)");
}

TEST_F(GlslWriterTest, IfWithElseIf) {
    auto* func = b.ComputeFunction("main");
    b.Append(func->Block(), [&] {
        auto* if_ = b.If(true);
        b.Append(if_->True(), [&] { b.ExitIf(if_); });
        b.Append(if_->False(), [&] {
            auto* false_ = b.If(false);
            b.Append(false_->True(), [&] { b.ExitIf(false_); });
            b.ExitIf(if_);
        });
        b.Return(func);
    });

    auto result = Generate();
    ASSERT_EQ(result, Success) << result.Failure().reason << output_.glsl;
    EXPECT_EQ(output_.glsl, GlslHeader() + R"(
layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
void main() {
  if (true) {
  } else {
    if (false) {
    }
  }
}
)");
}

TEST_F(GlslWriterTest, IfWithElse) {
    auto* func = b.ComputeFunction("main");
    b.Append(func->Block(), [&] {
        auto* if_ = b.If(true);
        b.Append(if_->True(), [&] { b.ExitIf(if_); });
        b.Append(if_->False(), [&] { b.Return(func); });
        b.Return(func);
    });

    auto result = Generate();
    ASSERT_EQ(result, Success) << result.Failure().reason << output_.glsl;
    EXPECT_EQ(output_.glsl, GlslHeader() + R"(
layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
void main() {
  if (true) {
  } else {
    return;
  }
}
)");
}

TEST_F(GlslWriterTest, IfBothBranchesReturn) {
    auto* func = b.ComputeFunction("main");
    b.Append(func->Block(), [&] {
        auto* if_ = b.If(true);
        b.Append(if_->True(), [&] { b.Return(func); });
        b.Append(if_->False(), [&] { b.Return(func); });
        b.Unreachable();
    });

    auto result = Generate();
    ASSERT_EQ(result, Success) << result.Failure().reason << output_.glsl;
    EXPECT_EQ(output_.glsl, GlslHeader() + R"(
layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
void main() {
  if (true) {
    return;
  } else {
    return;
  }
  /* unreachable */
}
)");
}

TEST_F(GlslWriterTest, IfBothBranchesReturn_NonVoidFunction) {
    auto* func = b.Function("foo", ty.u32());
    b.Append(func->Block(), [&] {
        auto* if_ = b.If(true);
        b.Append(if_->True(), [&] { b.Return(func, 0_u); });
        b.Append(if_->False(), [&] { b.Return(func, 1_u); });
        b.Unreachable();
    });

    auto* eb = b.ComputeFunction("main");
    b.Append(eb->Block(), [&] {
        b.Let("x", b.Call(func));
        b.Return(eb);
    });

    auto result = Generate();
    ASSERT_EQ(result, Success) << result.Failure().reason << output_.glsl;
    EXPECT_EQ(output_.glsl, GlslHeader() + R"(
uint foo() {
  if (true) {
    return 0u;
  } else {
    return 1u;
  }
  /* unreachable */
  return 0u;
}
layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
void main() {
  uint x = foo();
}
)");
}

TEST_F(GlslWriterTest, IfWithSinglePhi) {
    auto* func = b.ComputeFunction("main");
    b.Append(func->Block(), [&] {
        auto* i = b.If(true);
        i->SetResult(b.InstructionResult(ty.i32()));
        b.Append(i->True(), [&] {  //
            b.ExitIf(i, 10_i);
        });
        b.Append(i->False(), [&] {  //
            b.ExitIf(i, 20_i);
        });
        b.Return(func);
    });

    auto result = Generate();
    ASSERT_EQ(result, Success) << result.Failure().reason << output_.glsl;
    EXPECT_EQ(output_.glsl, GlslHeader() + R"(
layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
void main() {
  int v = 0;
  if (true) {
    v = 10;
  } else {
    v = 20;
  }
}
)");
}

TEST_F(GlslWriterTest, IfWithMultiPhi) {
    auto* func = b.ComputeFunction("main");
    b.Append(func->Block(), [&] {
        auto* i = b.If(true);
        i->SetResults(b.InstructionResult(ty.i32()), b.InstructionResult(ty.bool_()));
        b.Append(i->True(), [&] {  //
            b.ExitIf(i, 10_i, true);
        });
        b.Append(i->False(), [&] {  //
            b.ExitIf(i, 20_i, false);
        });
        b.Return(func);
    });

    auto result = Generate();
    ASSERT_EQ(result, Success) << result.Failure().reason << output_.glsl;
    EXPECT_EQ(output_.glsl, GlslHeader() + R"(
layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
void main() {
  int v = 0;
  bool v_1 = false;
  if (true) {
    v = 10;
    v_1 = true;
  } else {
    v = 20;
    v_1 = false;
  }
}
)");
}

TEST_F(GlslWriterTest, IfWithMultiPhiReturn1) {
    auto* func = b.Function("foo", ty.i32());
    b.Append(func->Block(), [&] {
        auto* i = b.If(true);
        i->SetResults(b.InstructionResult(ty.i32()), b.InstructionResult(ty.bool_()));
        b.Append(i->True(), [&] {  //
            b.ExitIf(i, 10_i, true);
        });
        b.Append(i->False(), [&] {  //
            b.ExitIf(i, 20_i, false);
        });
        b.Return(func, i->Result(0));
    });

    auto* eb = b.ComputeFunction("main");
    b.Append(eb->Block(), [&] {
        b.Let("x", b.Call(func));
        b.Return(eb);
    });

    auto result = Generate();
    ASSERT_EQ(result, Success) << result.Failure().reason << output_.glsl;
    EXPECT_EQ(output_.glsl, GlslHeader() + R"(
int foo() {
  int v = 0;
  bool v_1 = false;
  if (true) {
    v = 10;
    v_1 = true;
  } else {
    v = 20;
    v_1 = false;
  }
  return v;
}
layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
void main() {
  int x = foo();
}
)");
}

TEST_F(GlslWriterTest, IfWithMultiPhiReturn2) {
    auto* func = b.Function("foo", ty.bool_());
    b.Append(func->Block(), [&] {
        auto* i = b.If(true);
        i->SetResults(b.InstructionResult(ty.i32()), b.InstructionResult(ty.bool_()));
        b.Append(i->True(), [&] {  //
            b.ExitIf(i, 10_i, true);
        });
        b.Append(i->False(), [&] {  //
            b.ExitIf(i, 20_i, false);
        });
        b.Return(func, i->Result(1));
    });

    auto* eb = b.ComputeFunction("main");
    b.Append(eb->Block(), [&] {
        b.Let("x", b.Call(func));
        b.Return(eb);
    });

    auto result = Generate();
    ASSERT_EQ(result, Success) << result.Failure().reason << output_.glsl;
    EXPECT_EQ(output_.glsl, GlslHeader() + R"(
bool foo() {
  int v = 0;
  bool v_1 = false;
  if (true) {
    v = 10;
    v_1 = true;
  } else {
    v = 20;
    v_1 = false;
  }
  return v_1;
}
layout(local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
void main() {
  bool x = foo();
}
)");
}

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