// 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 "src/tint/ast/call_statement.h"
#include "src/tint/sem/call.h"
#include "src/tint/writer/msl/test_helper.h"

namespace tint::writer::msl {
namespace {

using BuiltinType = sem::BuiltinType;

using MslGeneratorImplTest = TestHelper;

enum class ParamType {
  kF32,
  kU32,
  kBool,
};

struct BuiltinData {
  BuiltinType builtin;
  ParamType type;
  const char* msl_name;
};
inline std::ostream& operator<<(std::ostream& out, BuiltinData data) {
  out << data.msl_name << "<";
  switch (data.type) {
    case ParamType::kF32:
      out << "f32";
      break;
    case ParamType::kU32:
      out << "u32";
      break;
    case ParamType::kBool:
      out << "bool";
      break;
  }
  out << ">";
  return out;
}

const ast::CallExpression* GenerateCall(BuiltinType builtin,
                                        ParamType type,
                                        ProgramBuilder* builder) {
  std::string name;
  std::ostringstream str(name);
  str << builtin;
  switch (builtin) {
    case BuiltinType::kAcos:
    case BuiltinType::kAsin:
    case BuiltinType::kAtan:
    case BuiltinType::kCeil:
    case BuiltinType::kCos:
    case BuiltinType::kCosh:
    case BuiltinType::kDpdx:
    case BuiltinType::kDpdxCoarse:
    case BuiltinType::kDpdxFine:
    case BuiltinType::kDpdy:
    case BuiltinType::kDpdyCoarse:
    case BuiltinType::kDpdyFine:
    case BuiltinType::kExp:
    case BuiltinType::kExp2:
    case BuiltinType::kFloor:
    case BuiltinType::kFract:
    case BuiltinType::kFwidth:
    case BuiltinType::kFwidthCoarse:
    case BuiltinType::kFwidthFine:
    case BuiltinType::kInverseSqrt:
    case BuiltinType::kLength:
    case BuiltinType::kLog:
    case BuiltinType::kLog2:
    case BuiltinType::kNormalize:
    case BuiltinType::kRound:
    case BuiltinType::kSin:
    case BuiltinType::kSinh:
    case BuiltinType::kSqrt:
    case BuiltinType::kTan:
    case BuiltinType::kTanh:
    case BuiltinType::kTrunc:
    case BuiltinType::kSign:
      return builder->Call(str.str(), "f2");
    case BuiltinType::kLdexp:
      return builder->Call(str.str(), "f2", "i2");
    case BuiltinType::kAtan2:
    case BuiltinType::kDot:
    case BuiltinType::kDistance:
    case BuiltinType::kPow:
    case BuiltinType::kReflect:
    case BuiltinType::kStep:
      return builder->Call(str.str(), "f2", "f2");
    case BuiltinType::kStorageBarrier:
      return builder->Call(str.str());
    case BuiltinType::kCross:
      return builder->Call(str.str(), "f3", "f3");
    case BuiltinType::kFma:
    case BuiltinType::kMix:
    case BuiltinType::kFaceForward:
    case BuiltinType::kSmoothstep:
    case BuiltinType::kSmoothStep:
      return builder->Call(str.str(), "f2", "f2", "f2");
    case BuiltinType::kAll:
    case BuiltinType::kAny:
      return builder->Call(str.str(), "b2");
    case BuiltinType::kAbs:
      if (type == ParamType::kF32) {
        return builder->Call(str.str(), "f2");
      } else {
        return builder->Call(str.str(), "u2");
      }
    case BuiltinType::kCountLeadingZeros:
    case BuiltinType::kCountOneBits:
    case BuiltinType::kCountTrailingZeros:
    case BuiltinType::kReverseBits:
      return builder->Call(str.str(), "u2");
    case BuiltinType::kExtractBits:
      return builder->Call(str.str(), "u2", "u1", "u1");
    case BuiltinType::kInsertBits:
      return builder->Call(str.str(), "u2", "u2", "u1", "u1");
    case BuiltinType::kMax:
    case BuiltinType::kMin:
      if (type == ParamType::kF32) {
        return builder->Call(str.str(), "f2", "f2");
      } else {
        return builder->Call(str.str(), "u2", "u2");
      }
    case BuiltinType::kClamp:
      if (type == ParamType::kF32) {
        return builder->Call(str.str(), "f2", "f2", "f2");
      } else {
        return builder->Call(str.str(), "u2", "u2", "u2");
      }
    case BuiltinType::kSelect:
      return builder->Call(str.str(), "f2", "f2", "b2");
    case BuiltinType::kDeterminant:
      return builder->Call(str.str(), "m2x2");
    case BuiltinType::kPack2x16snorm:
    case BuiltinType::kPack2x16unorm:
      return builder->Call(str.str(), "f2");
    case BuiltinType::kPack4x8snorm:
    case BuiltinType::kPack4x8unorm:
      return builder->Call(str.str(), "f4");
    case BuiltinType::kUnpack4x8snorm:
    case BuiltinType::kUnpack4x8unorm:
    case BuiltinType::kUnpack2x16snorm:
    case BuiltinType::kUnpack2x16unorm:
      return builder->Call(str.str(), "u1");
    case BuiltinType::kWorkgroupBarrier:
      return builder->Call(str.str());
    case BuiltinType::kTranspose:
      return builder->Call(str.str(), "m3x2");
    default:
      break;
  }
  return nullptr;
}

using MslBuiltinTest = TestParamHelper<BuiltinData>;
TEST_P(MslBuiltinTest, Emit) {
  auto param = GetParam();

  Global("f2", ty.vec2<f32>(), ast::StorageClass::kPrivate);
  Global("f3", ty.vec3<f32>(), ast::StorageClass::kPrivate);
  Global("f4", ty.vec4<f32>(), ast::StorageClass::kPrivate);
  Global("u1", ty.u32(), ast::StorageClass::kPrivate);
  Global("u2", ty.vec2<u32>(), ast::StorageClass::kPrivate);
  Global("i2", ty.vec2<i32>(), ast::StorageClass::kPrivate);
  Global("b2", ty.vec2<bool>(), ast::StorageClass::kPrivate);
  Global("m2x2", ty.mat2x2<f32>(), ast::StorageClass::kPrivate);
  Global("m3x2", ty.mat3x2<f32>(), ast::StorageClass::kPrivate);

  auto* call = GenerateCall(param.builtin, param.type, this);
  ASSERT_NE(nullptr, call) << "Unhandled builtin";
  Func("func", {}, ty.void_(), {Ignore(call)},
       {create<ast::StageAttribute>(ast::PipelineStage::kFragment)});

  GeneratorImpl& gen = Build();

  auto* sem = program->Sem().Get(call);
  ASSERT_NE(sem, nullptr);
  auto* target = sem->Target();
  ASSERT_NE(target, nullptr);
  auto* builtin = target->As<sem::Builtin>();
  ASSERT_NE(builtin, nullptr);

  EXPECT_EQ(gen.generate_builtin_name(builtin), param.msl_name);
}
INSTANTIATE_TEST_SUITE_P(
    MslGeneratorImplTest,
    MslBuiltinTest,
    testing::Values(
        BuiltinData{BuiltinType::kAbs, ParamType::kF32, "fabs"},
        BuiltinData{BuiltinType::kAbs, ParamType::kU32, "abs"},
        BuiltinData{BuiltinType::kAcos, ParamType::kF32, "acos"},
        BuiltinData{BuiltinType::kAll, ParamType::kBool, "all"},
        BuiltinData{BuiltinType::kAny, ParamType::kBool, "any"},
        BuiltinData{BuiltinType::kAsin, ParamType::kF32, "asin"},
        BuiltinData{BuiltinType::kAtan, ParamType::kF32, "atan"},
        BuiltinData{BuiltinType::kAtan2, ParamType::kF32, "atan2"},
        BuiltinData{BuiltinType::kCeil, ParamType::kF32, "ceil"},
        BuiltinData{BuiltinType::kClamp, ParamType::kF32, "clamp"},
        BuiltinData{BuiltinType::kClamp, ParamType::kU32, "clamp"},
        BuiltinData{BuiltinType::kCos, ParamType::kF32, "cos"},
        BuiltinData{BuiltinType::kCosh, ParamType::kF32, "cosh"},
        BuiltinData{BuiltinType::kCountLeadingZeros, ParamType::kU32, "clz"},
        BuiltinData{BuiltinType::kCountOneBits, ParamType::kU32, "popcount"},
        BuiltinData{BuiltinType::kCountTrailingZeros, ParamType::kU32, "ctz"},
        BuiltinData{BuiltinType::kCross, ParamType::kF32, "cross"},
        BuiltinData{BuiltinType::kDeterminant, ParamType::kF32, "determinant"},
        BuiltinData{BuiltinType::kDistance, ParamType::kF32, "distance"},
        BuiltinData{BuiltinType::kDot, ParamType::kF32, "dot"},
        BuiltinData{BuiltinType::kDpdx, ParamType::kF32, "dfdx"},
        BuiltinData{BuiltinType::kDpdxCoarse, ParamType::kF32, "dfdx"},
        BuiltinData{BuiltinType::kDpdxFine, ParamType::kF32, "dfdx"},
        BuiltinData{BuiltinType::kDpdy, ParamType::kF32, "dfdy"},
        BuiltinData{BuiltinType::kDpdyCoarse, ParamType::kF32, "dfdy"},
        BuiltinData{BuiltinType::kDpdyFine, ParamType::kF32, "dfdy"},
        BuiltinData{BuiltinType::kExp, ParamType::kF32, "exp"},
        BuiltinData{BuiltinType::kExp2, ParamType::kF32, "exp2"},
        BuiltinData{BuiltinType::kExtractBits, ParamType::kU32, "extract_bits"},
        BuiltinData{BuiltinType::kFaceForward, ParamType::kF32, "faceforward"},
        BuiltinData{BuiltinType::kFloor, ParamType::kF32, "floor"},
        BuiltinData{BuiltinType::kFma, ParamType::kF32, "fma"},
        BuiltinData{BuiltinType::kFract, ParamType::kF32, "fract"},
        BuiltinData{BuiltinType::kFwidth, ParamType::kF32, "fwidth"},
        BuiltinData{BuiltinType::kFwidthCoarse, ParamType::kF32, "fwidth"},
        BuiltinData{BuiltinType::kFwidthFine, ParamType::kF32, "fwidth"},
        BuiltinData{BuiltinType::kInsertBits, ParamType::kU32, "insert_bits"},
        BuiltinData{BuiltinType::kInverseSqrt, ParamType::kF32, "rsqrt"},
        BuiltinData{BuiltinType::kLdexp, ParamType::kF32, "ldexp"},
        BuiltinData{BuiltinType::kLength, ParamType::kF32, "length"},
        BuiltinData{BuiltinType::kLog, ParamType::kF32, "log"},
        BuiltinData{BuiltinType::kLog2, ParamType::kF32, "log2"},
        BuiltinData{BuiltinType::kMax, ParamType::kF32, "fmax"},
        BuiltinData{BuiltinType::kMax, ParamType::kU32, "max"},
        BuiltinData{BuiltinType::kMin, ParamType::kF32, "fmin"},
        BuiltinData{BuiltinType::kMin, ParamType::kU32, "min"},
        BuiltinData{BuiltinType::kNormalize, ParamType::kF32, "normalize"},
        BuiltinData{BuiltinType::kPack4x8snorm, ParamType::kF32,
                    "pack_float_to_snorm4x8"},
        BuiltinData{BuiltinType::kPack4x8unorm, ParamType::kF32,
                    "pack_float_to_unorm4x8"},
        BuiltinData{BuiltinType::kPack2x16snorm, ParamType::kF32,
                    "pack_float_to_snorm2x16"},
        BuiltinData{BuiltinType::kPack2x16unorm, ParamType::kF32,
                    "pack_float_to_unorm2x16"},
        BuiltinData{BuiltinType::kPow, ParamType::kF32, "pow"},
        BuiltinData{BuiltinType::kReflect, ParamType::kF32, "reflect"},
        BuiltinData{BuiltinType::kReverseBits, ParamType::kU32, "reverse_bits"},
        BuiltinData{BuiltinType::kRound, ParamType::kU32, "rint"},
        BuiltinData{BuiltinType::kSelect, ParamType::kF32, "select"},
        BuiltinData{BuiltinType::kSign, ParamType::kF32, "sign"},
        BuiltinData{BuiltinType::kSin, ParamType::kF32, "sin"},
        BuiltinData{BuiltinType::kSinh, ParamType::kF32, "sinh"},
        BuiltinData{BuiltinType::kSmoothstep, ParamType::kF32, "smoothstep"},
        BuiltinData{BuiltinType::kSmoothStep, ParamType::kF32, "smoothstep"},
        BuiltinData{BuiltinType::kSqrt, ParamType::kF32, "sqrt"},
        BuiltinData{BuiltinType::kStep, ParamType::kF32, "step"},
        BuiltinData{BuiltinType::kTan, ParamType::kF32, "tan"},
        BuiltinData{BuiltinType::kTanh, ParamType::kF32, "tanh"},
        BuiltinData{BuiltinType::kTranspose, ParamType::kF32, "transpose"},
        BuiltinData{BuiltinType::kTrunc, ParamType::kF32, "trunc"},
        BuiltinData{BuiltinType::kUnpack4x8snorm, ParamType::kU32,
                    "unpack_snorm4x8_to_float"},
        BuiltinData{BuiltinType::kUnpack4x8unorm, ParamType::kU32,
                    "unpack_unorm4x8_to_float"},
        BuiltinData{BuiltinType::kUnpack2x16snorm, ParamType::kU32,
                    "unpack_snorm2x16_to_float"},
        BuiltinData{BuiltinType::kUnpack2x16unorm, ParamType::kU32,
                    "unpack_unorm2x16_to_float"}));

TEST_F(MslGeneratorImplTest, Builtin_Call) {
  Global("param1", ty.vec2<f32>(), ast::StorageClass::kPrivate);
  Global("param2", ty.vec2<f32>(), ast::StorageClass::kPrivate);

  auto* call = Call("dot", "param1", "param2");
  WrapInFunction(CallStmt(call));

  GeneratorImpl& gen = Build();

  std::stringstream out;
  ASSERT_TRUE(gen.EmitExpression(out, call)) << gen.error();
  EXPECT_EQ(out.str(), "dot(param1, param2)");
}

TEST_F(MslGeneratorImplTest, StorageBarrier) {
  auto* call = Call("storageBarrier");
  WrapInFunction(CallStmt(call));

  GeneratorImpl& gen = Build();

  std::stringstream out;
  ASSERT_TRUE(gen.EmitExpression(out, call)) << gen.error();
  EXPECT_EQ(out.str(), "threadgroup_barrier(mem_flags::mem_device)");
}

TEST_F(MslGeneratorImplTest, WorkgroupBarrier) {
  auto* call = Call("workgroupBarrier");
  WrapInFunction(CallStmt(call));

  GeneratorImpl& gen = Build();

  std::stringstream out;
  ASSERT_TRUE(gen.EmitExpression(out, call)) << gen.error();
  EXPECT_EQ(out.str(), "threadgroup_barrier(mem_flags::mem_threadgroup)");
}

TEST_F(MslGeneratorImplTest, Degrees_Scalar) {
  auto* val = Var("val", ty.f32());
  auto* call = Call("degrees", val);
  WrapInFunction(val, call);

  GeneratorImpl& gen = Build();

  ASSERT_TRUE(gen.Generate()) << gen.error();
  EXPECT_EQ(gen.result(), R"(#include <metal_stdlib>

using namespace metal;

float tint_degrees(float param_0) {
  return param_0 * 57.295779513082322865;
}

kernel void test_function() {
  float val = 0.0f;
  float const tint_symbol = tint_degrees(val);
  return;
}

)");
}

TEST_F(MslGeneratorImplTest, Degrees_Vector) {
  auto* val = Var("val", ty.vec3<f32>());
  auto* call = Call("degrees", val);
  WrapInFunction(val, call);

  GeneratorImpl& gen = Build();

  ASSERT_TRUE(gen.Generate()) << gen.error();
  EXPECT_EQ(gen.result(), R"(#include <metal_stdlib>

using namespace metal;

float3 tint_degrees(float3 param_0) {
  return param_0 * 57.295779513082322865;
}

kernel void test_function() {
  float3 val = 0.0f;
  float3 const tint_symbol = tint_degrees(val);
  return;
}

)");
}

TEST_F(MslGeneratorImplTest, Radians_Scalar) {
  auto* val = Var("val", ty.f32());
  auto* call = Call("radians", val);
  WrapInFunction(val, call);

  GeneratorImpl& gen = Build();

  ASSERT_TRUE(gen.Generate()) << gen.error();
  EXPECT_EQ(gen.result(), R"(#include <metal_stdlib>

using namespace metal;

float tint_radians(float param_0) {
  return param_0 * 0.017453292519943295474;
}

kernel void test_function() {
  float val = 0.0f;
  float const tint_symbol = tint_radians(val);
  return;
}

)");
}

TEST_F(MslGeneratorImplTest, Radians_Vector) {
  auto* val = Var("val", ty.vec3<f32>());
  auto* call = Call("radians", val);
  WrapInFunction(val, call);

  GeneratorImpl& gen = Build();

  ASSERT_TRUE(gen.Generate()) << gen.error();
  EXPECT_EQ(gen.result(), R"(#include <metal_stdlib>

using namespace metal;

float3 tint_radians(float3 param_0) {
  return param_0 * 0.017453292519943295474;
}

kernel void test_function() {
  float3 val = 0.0f;
  float3 const tint_symbol = tint_radians(val);
  return;
}

)");
}

TEST_F(MslGeneratorImplTest, Pack2x16Float) {
  auto* call = Call("pack2x16float", "p1");
  Global("p1", ty.vec2<f32>(), ast::StorageClass::kPrivate);
  WrapInFunction(CallStmt(call));

  GeneratorImpl& gen = Build();

  std::stringstream out;
  ASSERT_TRUE(gen.EmitExpression(out, call)) << gen.error();
  EXPECT_EQ(out.str(), "as_type<uint>(half2(p1))");
}

TEST_F(MslGeneratorImplTest, Unpack2x16Float) {
  auto* call = Call("unpack2x16float", "p1");
  Global("p1", ty.u32(), ast::StorageClass::kPrivate);
  WrapInFunction(CallStmt(call));

  GeneratorImpl& gen = Build();

  std::stringstream out;
  ASSERT_TRUE(gen.EmitExpression(out, call)) << gen.error();
  EXPECT_EQ(out.str(), "float2(as_type<half2>(p1))");
}

TEST_F(MslGeneratorImplTest, DotI32) {
  Global("v", ty.vec3<i32>(), ast::StorageClass::kPrivate);
  WrapInFunction(CallStmt(Call("dot", "v", "v")));

  GeneratorImpl& gen = SanitizeAndBuild();

  ASSERT_TRUE(gen.Generate()) << gen.error();
  EXPECT_EQ(gen.result(), R"(#include <metal_stdlib>

using namespace metal;

template<typename T>
T tint_dot3(vec<T,3> a, vec<T,3> b) {
  return a[0]*b[0] + a[1]*b[1] + a[2]*b[2];
}
kernel void test_function() {
  thread int3 tint_symbol = 0;
  tint_dot3(tint_symbol, tint_symbol);
  return;
}

)");
}

TEST_F(MslGeneratorImplTest, Ignore) {
  Func("f", {Param("a", ty.i32()), Param("b", ty.i32()), Param("c", ty.i32())},
       ty.i32(), {Return(Mul(Add("a", "b"), "c"))});

  Func("func", {}, ty.void_(), {CallStmt(Call("f", 1, 2, 3))},
       {
           Stage(ast::PipelineStage::kCompute),
           WorkgroupSize(1),
       });

  GeneratorImpl& gen = Build();

  ASSERT_TRUE(gen.Generate()) << gen.error();
  EXPECT_EQ(gen.result(), R"(#include <metal_stdlib>

using namespace metal;
int f(int a, int b, int c) {
  return as_type<int>((as_type<uint>(as_type<int>((as_type<uint>(a) + as_type<uint>(b)))) * as_type<uint>(c)));
}

kernel void func() {
  f(1, 2, 3);
  return;
}

)");
}

}  // namespace
}  // namespace tint::writer::msl