// 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/transform/array_length_from_uniform.h"

#include <utility>

#include "src/transform/inline_pointer_lets.h"
#include "src/transform/simplify.h"
#include "src/transform/test_helper.h"

namespace tint {
namespace transform {
namespace {

using ArrayLengthFromUniformTest = TransformTest;

TEST_F(ArrayLengthFromUniformTest, Error_MissingTransformData) {
  auto* src = "";

  auto* expect = "error: missing transform data for ArrayLengthFromUniform";

  auto got = Run<InlinePointerLets, Simplify, ArrayLengthFromUniform>(src);

  EXPECT_EQ(expect, str(got));
}

TEST_F(ArrayLengthFromUniformTest, Error_MissingInlinePointerLets) {
  auto* src = "";

  auto* expect =
      "error: tint::transform::ArrayLengthFromUniform depends on "
      "tint::transform::InlinePointerLets but the dependency was not run";

  auto got = Run<Simplify, ArrayLengthFromUniform>(src);

  EXPECT_EQ(expect, str(got));
}

TEST_F(ArrayLengthFromUniformTest, Error_MissingSimplify) {
  auto* src = "";

  auto* expect =
      "error: tint::transform::ArrayLengthFromUniform depends on "
      "tint::transform::Simplify but the dependency was not run";

  auto got = Run<InlinePointerLets, ArrayLengthFromUniform>(src);

  EXPECT_EQ(expect, str(got));
}

TEST_F(ArrayLengthFromUniformTest, Basic) {
  auto* src = R"(
[[block]]
struct SB {
  x : i32;
  arr : array<i32>;
};

[[group(0), binding(0)]] var<storage, read> sb : SB;

[[stage(compute), workgroup_size(1)]]
fn main() {
  var len : u32 = arrayLength(&sb.arr);
}
)";

  auto* expect = R"(
[[block]]
struct tint_symbol {
  buffer_size : array<u32, 1>;
};

[[group(0), binding(30)]] var<uniform> tint_symbol_1 : tint_symbol;

[[block]]
struct SB {
  x : i32;
  arr : array<i32>;
};

[[group(0), binding(0)]] var<storage, read> sb : SB;

[[stage(compute), workgroup_size(1)]]
fn main() {
  var len : u32 = ((tint_symbol_1.buffer_size[0u] - 4u) / 4u);
}
)";

  ArrayLengthFromUniform::Config cfg({0, 30u});
  cfg.bindpoint_to_size_index.emplace(sem::BindingPoint{0, 0}, 0);

  DataMap data;
  data.Add<ArrayLengthFromUniform::Config>(std::move(cfg));

  auto got =
      Run<InlinePointerLets, Simplify, ArrayLengthFromUniform>(src, data);

  EXPECT_EQ(expect, str(got));
  EXPECT_TRUE(
      got.data.Get<ArrayLengthFromUniform::Result>()->needs_buffer_sizes);
}

TEST_F(ArrayLengthFromUniformTest, WithStride) {
  auto* src = R"(
[[block]]
struct SB {
  x : i32;
  y : f32;
  arr : [[stride(64)]] array<i32>;
};

[[group(0), binding(0)]] var<storage, read> sb : SB;

[[stage(compute), workgroup_size(1)]]
fn main() {
  var len : u32 = arrayLength(&sb.arr);
}
)";

  auto* expect = R"(
[[block]]
struct tint_symbol {
  buffer_size : array<u32, 1>;
};

[[group(0), binding(30)]] var<uniform> tint_symbol_1 : tint_symbol;

[[block]]
struct SB {
  x : i32;
  y : f32;
  arr : [[stride(64)]] array<i32>;
};

[[group(0), binding(0)]] var<storage, read> sb : SB;

[[stage(compute), workgroup_size(1)]]
fn main() {
  var len : u32 = ((tint_symbol_1.buffer_size[0u] - 8u) / 64u);
}
)";

  ArrayLengthFromUniform::Config cfg({0, 30u});
  cfg.bindpoint_to_size_index.emplace(sem::BindingPoint{0, 0}, 0);

  DataMap data;
  data.Add<ArrayLengthFromUniform::Config>(std::move(cfg));

  auto got =
      Run<InlinePointerLets, Simplify, ArrayLengthFromUniform>(src, data);

  EXPECT_EQ(expect, str(got));
  EXPECT_TRUE(
      got.data.Get<ArrayLengthFromUniform::Result>()->needs_buffer_sizes);
}

TEST_F(ArrayLengthFromUniformTest, MultipleStorageBuffers) {
  auto* src = R"(
[[block]]
struct SB1 {
  x : i32;
  arr1 : array<i32>;
};

[[block]]
struct SB2 {
  x : i32;
  arr2 : array<vec4<f32>>;
};

[[group(0), binding(2)]] var<storage, read> sb1 : SB1;

[[group(1), binding(2)]] var<storage, read> sb2 : SB2;

[[stage(compute), workgroup_size(1)]]
fn main() {
  var len1 : u32 = arrayLength(&(sb1.arr1));
  var len2 : u32 = arrayLength(&(sb2.arr2));
  var x : u32 = (len1 + len2);
}
)";

  auto* expect = R"(
[[block]]
struct tint_symbol {
  buffer_size : array<u32, 2>;
};

[[group(0), binding(30)]] var<uniform> tint_symbol_1 : tint_symbol;

[[block]]
struct SB1 {
  x : i32;
  arr1 : array<i32>;
};

[[block]]
struct SB2 {
  x : i32;
  arr2 : array<vec4<f32>>;
};

[[group(0), binding(2)]] var<storage, read> sb1 : SB1;

[[group(1), binding(2)]] var<storage, read> sb2 : SB2;

[[stage(compute), workgroup_size(1)]]
fn main() {
  var len1 : u32 = ((tint_symbol_1.buffer_size[0u] - 4u) / 4u);
  var len2 : u32 = ((tint_symbol_1.buffer_size[1u] - 16u) / 16u);
  var x : u32 = (len1 + len2);
}
)";

  ArrayLengthFromUniform::Config cfg({0, 30u});
  cfg.bindpoint_to_size_index.emplace(sem::BindingPoint{0, 2u}, 0);
  cfg.bindpoint_to_size_index.emplace(sem::BindingPoint{1u, 2u}, 1);

  DataMap data;
  data.Add<ArrayLengthFromUniform::Config>(std::move(cfg));

  auto got =
      Run<InlinePointerLets, Simplify, ArrayLengthFromUniform>(src, data);

  EXPECT_EQ(expect, str(got));
  EXPECT_TRUE(
      got.data.Get<ArrayLengthFromUniform::Result>()->needs_buffer_sizes);
}

TEST_F(ArrayLengthFromUniformTest, NoArrayLengthCalls) {
  auto* src = R"(
[[block]]
struct SB {
  x : i32;
  arr : array<i32>;
};

[[group(0), binding(0)]] var<storage, read> sb : SB;

[[stage(compute), workgroup_size(1)]]
fn main() {
  ignore(&(sb.arr));
}
)";

  ArrayLengthFromUniform::Config cfg({0, 30u});
  cfg.bindpoint_to_size_index.emplace(sem::BindingPoint{0, 0}, 0);

  DataMap data;
  data.Add<ArrayLengthFromUniform::Config>(std::move(cfg));

  auto got =
      Run<InlinePointerLets, Simplify, ArrayLengthFromUniform>(src, data);

  EXPECT_EQ(src, str(got));
  EXPECT_FALSE(
      got.data.Get<ArrayLengthFromUniform::Result>()->needs_buffer_sizes);
}

TEST_F(ArrayLengthFromUniformTest, MissingBindingPointToIndexMapping) {
  auto* src = R"(
[[block]]
struct SB1 {
  x : i32;
  arr1 : array<i32>;
};

[[block]]
struct SB2 {
  x : i32;
  arr2 : array<vec4<f32>>;
};

[[group(0), binding(2)]] var<storage, read> sb1 : SB1;

[[group(1), binding(2)]] var<storage, read> sb2 : SB2;

[[stage(compute), workgroup_size(1)]]
fn main() {
  var len1 : u32 = arrayLength(&(sb1.arr1));
  var len2 : u32 = arrayLength(&(sb2.arr2));
  var x : u32 = (len1 + len2);
}
)";

  auto* expect = "error: missing size index mapping for binding point (1,2)";

  ArrayLengthFromUniform::Config cfg({0, 30u});
  cfg.bindpoint_to_size_index.emplace(sem::BindingPoint{0, 2}, 0);

  DataMap data;
  data.Add<ArrayLengthFromUniform::Config>(std::move(cfg));

  auto got =
      Run<InlinePointerLets, Simplify, ArrayLengthFromUniform>(src, data);

  EXPECT_EQ(expect, str(got));
}

}  // namespace
}  // namespace transform
}  // namespace tint