// 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/ast/builtin_attribute.h"
#include "src/tint/ast/location_attribute.h"
#include "src/tint/ast/return_statement.h"
#include "src/tint/ast/stage_attribute.h"
#include "src/tint/resolver/resolver.h"
#include "src/tint/resolver/resolver_test_helper.h"

#include "gmock/gmock.h"

using namespace tint::number_suffixes;  // NOLINT

namespace tint::resolver {
namespace {

// Helpers and typedefs
template <typename T>
using DataType = builder::DataType<T>;
template <typename T>
using vec2 = builder::vec2<T>;
template <typename T>
using vec3 = builder::vec3<T>;
template <typename T>
using vec4 = builder::vec4<T>;
template <typename T>
using mat2x2 = builder::mat2x2<T>;
template <typename T>
using mat3x3 = builder::mat3x3<T>;
template <typename T>
using mat4x4 = builder::mat4x4<T>;
template <typename T>
using alias = builder::alias<T>;

class ResolverEntryPointValidationTest : public TestHelper, public testing::Test {};

TEST_F(ResolverEntryPointValidationTest, ReturnTypeAttribute_Location) {
    // @stage(fragment)
    // fn main() -> @location(0) f32 { return 1.0; }
    Func(Source{{12, 34}}, "main", {}, ty.f32(), {Return(1_f)},
         {Stage(ast::PipelineStage::kFragment)}, {Location(0)});

    EXPECT_TRUE(r()->Resolve()) << r()->error();
}

TEST_F(ResolverEntryPointValidationTest, ReturnTypeAttribute_Builtin) {
    // @stage(vertex)
    // fn main() -> @builtin(position) vec4<f32> { return vec4<f32>(); }
    Func(Source{{12, 34}}, "main", {}, ty.vec4<f32>(), {Return(Construct(ty.vec4<f32>()))},
         {Stage(ast::PipelineStage::kVertex)}, {Builtin(ast::Builtin::kPosition)});

    EXPECT_TRUE(r()->Resolve()) << r()->error();
}

TEST_F(ResolverEntryPointValidationTest, ReturnTypeAttribute_Missing) {
    // @stage(vertex)
    // fn main() -> f32 {
    //   return 1.0;
    // }
    Func(Source{{12, 34}}, "main", {}, ty.vec4<f32>(), {Return(Construct(ty.vec4<f32>()))},
         {Stage(ast::PipelineStage::kVertex)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), "12:34 error: missing entry point IO attribute on return type");
}

TEST_F(ResolverEntryPointValidationTest, ReturnTypeAttribute_Multiple) {
    // @stage(vertex)
    // fn main() -> @location(0) @builtin(position) vec4<f32> {
    //   return vec4<f32>();
    // }
    Func(Source{{12, 34}}, "main", {}, ty.vec4<f32>(), {Return(Construct(ty.vec4<f32>()))},
         {Stage(ast::PipelineStage::kVertex)},
         {Location(Source{{13, 43}}, 0), Builtin(Source{{14, 52}}, ast::Builtin::kPosition)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), R"(14:52 error: multiple entry point IO attributes
13:43 note: previously consumed location(0))");
}

TEST_F(ResolverEntryPointValidationTest, ReturnType_Struct_Valid) {
    // struct Output {
    //   @location(0) a : f32;
    //   @builtin(frag_depth) b : f32;
    // };
    // @stage(fragment)
    // fn main() -> Output {
    //   return Output();
    // }
    auto* output =
        Structure("Output", {Member("a", ty.f32(), {Location(0)}),
                             Member("b", ty.f32(), {Builtin(ast::Builtin::kFragDepth)})});
    Func(Source{{12, 34}}, "main", {}, ty.Of(output), {Return(Construct(ty.Of(output)))},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_TRUE(r()->Resolve()) << r()->error();
}

TEST_F(ResolverEntryPointValidationTest, ReturnType_Struct_MemberMultipleAttributes) {
    // struct Output {
    //   @location(0) @builtin(frag_depth) a : f32;
    // };
    // @stage(fragment)
    // fn main() -> Output {
    //   return Output();
    // }
    auto* output =
        Structure("Output", {Member("a", ty.f32(),
                                    {Location(Source{{13, 43}}, 0),
                                     Builtin(Source{{14, 52}}, ast::Builtin::kFragDepth)})});
    Func(Source{{12, 34}}, "main", {}, ty.Of(output), {Return(Construct(ty.Of(output)))},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), R"(14:52 error: multiple entry point IO attributes
13:43 note: previously consumed location(0)
12:34 note: while analysing entry point 'main')");
}

TEST_F(ResolverEntryPointValidationTest, ReturnType_Struct_MemberMissingAttribute) {
    // struct Output {
    //   @location(0) a : f32;
    //   b : f32;
    // };
    // @stage(fragment)
    // fn main() -> Output {
    //   return Output();
    // }
    auto* output = Structure("Output", {Member(Source{{13, 43}}, "a", ty.f32(), {Location(0)}),
                                        Member(Source{{14, 52}}, "b", ty.f32(), {})});
    Func(Source{{12, 34}}, "main", {}, ty.Of(output), {Return(Construct(ty.Of(output)))},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              R"(14:52 error: missing entry point IO attribute
12:34 note: while analysing entry point 'main')");
}

TEST_F(ResolverEntryPointValidationTest, ReturnType_Struct_DuplicateBuiltins) {
    // struct Output {
    //   @builtin(frag_depth) a : f32;
    //   @builtin(frag_depth) b : f32;
    // };
    // @stage(fragment)
    // fn main() -> Output {
    //   return Output();
    // }
    auto* output =
        Structure("Output", {Member("a", ty.f32(), {Builtin(ast::Builtin::kFragDepth)}),
                             Member("b", ty.f32(), {Builtin(ast::Builtin::kFragDepth)})});
    Func(Source{{12, 34}}, "main", {}, ty.Of(output), {Return(Construct(ty.Of(output)))},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(
        r()->error(),
        R"(12:34 error: builtin(frag_depth) attribute appears multiple times as pipeline output
12:34 note: while analysing entry point 'main')");
}

TEST_F(ResolverEntryPointValidationTest, ParameterAttribute_Location) {
    // @stage(fragment)
    // fn main(@location(0) param : f32) {}
    auto* param = Param("param", ty.f32(), {Location(0)});
    Func(Source{{12, 34}}, "main", {param}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_TRUE(r()->Resolve()) << r()->error();
}

TEST_F(ResolverEntryPointValidationTest, ParameterAttribute_Missing) {
    // @stage(fragment)
    // fn main(param : f32) {}
    auto* param = Param(Source{{13, 43}}, "param", ty.vec4<f32>());
    Func(Source{{12, 34}}, "main", {param}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), "13:43 error: missing entry point IO attribute on parameter");
}

TEST_F(ResolverEntryPointValidationTest, ParameterAttribute_Multiple) {
    // @stage(fragment)
    // fn main(@location(0) @builtin(sample_index) param : u32) {}
    auto* param = Param(
        "param", ty.u32(),
        {Location(Source{{13, 43}}, 0), Builtin(Source{{14, 52}}, ast::Builtin::kSampleIndex)});
    Func(Source{{12, 34}}, "main", {param}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), R"(14:52 error: multiple entry point IO attributes
13:43 note: previously consumed location(0))");
}

TEST_F(ResolverEntryPointValidationTest, Parameter_Struct_Valid) {
    // struct Input {
    //   @location(0) a : f32;
    //   @builtin(sample_index) b : u32;
    // };
    // @stage(fragment)
    // fn main(param : Input) {}
    auto* input =
        Structure("Input", {Member("a", ty.f32(), {Location(0)}),
                            Member("b", ty.u32(), {Builtin(ast::Builtin::kSampleIndex)})});
    auto* param = Param("param", ty.Of(input));
    Func(Source{{12, 34}}, "main", {param}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_TRUE(r()->Resolve()) << r()->error();
}

TEST_F(ResolverEntryPointValidationTest, Parameter_Struct_MemberMultipleAttributes) {
    // struct Input {
    //   @location(0) @builtin(sample_index) a : u32;
    // };
    // @stage(fragment)
    // fn main(param : Input) {}
    auto* input =
        Structure("Input", {Member("a", ty.u32(),
                                   {Location(Source{{13, 43}}, 0),
                                    Builtin(Source{{14, 52}}, ast::Builtin::kSampleIndex)})});
    auto* param = Param("param", ty.Of(input));
    Func(Source{{12, 34}}, "main", {param}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), R"(14:52 error: multiple entry point IO attributes
13:43 note: previously consumed location(0)
12:34 note: while analysing entry point 'main')");
}

TEST_F(ResolverEntryPointValidationTest, Parameter_Struct_MemberMissingAttribute) {
    // struct Input {
    //   @location(0) a : f32;
    //   b : f32;
    // };
    // @stage(fragment)
    // fn main(param : Input) {}
    auto* input = Structure("Input", {Member(Source{{13, 43}}, "a", ty.f32(), {Location(0)}),
                                      Member(Source{{14, 52}}, "b", ty.f32(), {})});
    auto* param = Param("param", ty.Of(input));
    Func(Source{{12, 34}}, "main", {param}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), R"(14:52 error: missing entry point IO attribute
12:34 note: while analysing entry point 'main')");
}

TEST_F(ResolverEntryPointValidationTest, Parameter_DuplicateBuiltins) {
    // @stage(fragment)
    // fn main(@builtin(sample_index) param_a : u32,
    //         @builtin(sample_index) param_b : u32) {}
    auto* param_a = Param("param_a", ty.u32(), {Builtin(ast::Builtin::kSampleIndex)});
    auto* param_b = Param("param_b", ty.u32(), {Builtin(ast::Builtin::kSampleIndex)});
    Func(Source{{12, 34}}, "main", {param_a, param_b}, ty.void_(), {},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "12:34 error: builtin(sample_index) attribute appears multiple times as "
              "pipeline input");
}

TEST_F(ResolverEntryPointValidationTest, Parameter_Struct_DuplicateBuiltins) {
    // struct InputA {
    //   @builtin(sample_index) a : u32;
    // };
    // struct InputB {
    //   @builtin(sample_index) a : u32;
    // };
    // @stage(fragment)
    // fn main(param_a : InputA, param_b : InputB) {}
    auto* input_a =
        Structure("InputA", {Member("a", ty.u32(), {Builtin(ast::Builtin::kSampleIndex)})});
    auto* input_b =
        Structure("InputB", {Member("a", ty.u32(), {Builtin(ast::Builtin::kSampleIndex)})});
    auto* param_a = Param("param_a", ty.Of(input_a));
    auto* param_b = Param("param_b", ty.Of(input_b));
    Func(Source{{12, 34}}, "main", {param_a, param_b}, ty.void_(), {},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(
        r()->error(),
        R"(12:34 error: builtin(sample_index) attribute appears multiple times as pipeline input
12:34 note: while analysing entry point 'main')");
}

TEST_F(ResolverEntryPointValidationTest, VertexShaderMustReturnPosition) {
    // @stage(vertex)
    // fn main() {}
    Func(Source{{12, 34}}, "main", {}, ty.void_(), {}, {Stage(ast::PipelineStage::kVertex)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "12:34 error: a vertex shader must include the 'position' builtin "
              "in its return type");
}

namespace TypeValidationTests {
struct Params {
    builder::ast_type_func_ptr create_ast_type;
    bool is_valid;
};

template <typename T>
constexpr Params ParamsFor(bool is_valid) {
    return Params{DataType<T>::AST, is_valid};
}

using TypeValidationTest = resolver::ResolverTestWithParam<Params>;

static constexpr Params cases[] = {
    ParamsFor<f32>(true),           //
    ParamsFor<i32>(true),           //
    ParamsFor<u32>(true),           //
    ParamsFor<bool>(false),         //
    ParamsFor<vec2<f32>>(true),     //
    ParamsFor<vec3<f32>>(true),     //
    ParamsFor<vec4<f32>>(true),     //
    ParamsFor<mat2x2<f32>>(false),  //
    ParamsFor<mat3x3<f32>>(false),  //
    ParamsFor<mat4x4<f32>>(false),  //
    ParamsFor<alias<f32>>(true),    //
    ParamsFor<alias<i32>>(true),    //
    ParamsFor<alias<u32>>(true),    //
    ParamsFor<alias<bool>>(false),  //
};

TEST_P(TypeValidationTest, BareInputs) {
    // @stage(fragment)
    // fn main(@location(0) @interpolate(flat) a : *) {}
    auto params = GetParam();
    auto* a = Param("a", params.create_ast_type(*this), {Location(0), Flat()});
    Func(Source{{12, 34}}, "main", {a}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    if (params.is_valid) {
        EXPECT_TRUE(r()->Resolve()) << r()->error();
    } else {
        EXPECT_FALSE(r()->Resolve());
    }
}

TEST_P(TypeValidationTest, StructInputs) {
    // struct Input {
    //   @location(0) @interpolate(flat) a : *;
    // };
    // @stage(fragment)
    // fn main(a : Input) {}
    auto params = GetParam();
    auto* input =
        Structure("Input", {Member("a", params.create_ast_type(*this), {Location(0), Flat()})});
    auto* a = Param("a", ty.Of(input), {});
    Func(Source{{12, 34}}, "main", {a}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    if (params.is_valid) {
        EXPECT_TRUE(r()->Resolve()) << r()->error();
    } else {
        EXPECT_FALSE(r()->Resolve());
    }
}

TEST_P(TypeValidationTest, BareOutputs) {
    // @stage(fragment)
    // fn main() -> @location(0) * {
    //   return *();
    // }
    auto params = GetParam();
    Func(Source{{12, 34}}, "main", {}, params.create_ast_type(*this),
         {Return(Construct(params.create_ast_type(*this)))}, {Stage(ast::PipelineStage::kFragment)},
         {Location(0)});

    if (params.is_valid) {
        EXPECT_TRUE(r()->Resolve()) << r()->error();
    } else {
        EXPECT_FALSE(r()->Resolve());
    }
}

TEST_P(TypeValidationTest, StructOutputs) {
    // struct Output {
    //   @location(0) a : *;
    // };
    // @stage(fragment)
    // fn main() -> Output {
    //   return Output();
    // }
    auto params = GetParam();
    auto* output = Structure("Output", {Member("a", params.create_ast_type(*this), {Location(0)})});
    Func(Source{{12, 34}}, "main", {}, ty.Of(output), {Return(Construct(ty.Of(output)))},
         {Stage(ast::PipelineStage::kFragment)});

    if (params.is_valid) {
        EXPECT_TRUE(r()->Resolve()) << r()->error();
    } else {
        EXPECT_FALSE(r()->Resolve());
    }
}
INSTANTIATE_TEST_SUITE_P(ResolverEntryPointValidationTest,
                         TypeValidationTest,
                         testing::ValuesIn(cases));

}  // namespace TypeValidationTests

namespace LocationAttributeTests {
namespace {
using LocationAttributeTests = ResolverTest;

TEST_F(LocationAttributeTests, Pass) {
    // @stage(fragment)
    // fn frag_main(@location(0) @interpolate(flat) a: i32) {}

    auto* p = Param(Source{{12, 34}}, "a", ty.i32(), {Location(0), Flat()});
    Func("frag_main", {p}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_TRUE(r()->Resolve()) << r()->error();
}

TEST_F(LocationAttributeTests, BadType_Input_bool) {
    // @stage(fragment)
    // fn frag_main(@location(0) a: bool) {}

    auto* p = Param(Source{{12, 34}}, "a", ty.bool_(), {Location(Source{{34, 56}}, 0)});
    Func("frag_main", {p}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "12:34 error: cannot apply 'location' attribute to declaration of "
              "type 'bool'\n"
              "34:56 note: 'location' attribute must only be applied to "
              "declarations of numeric scalar or numeric vector type");
}

TEST_F(LocationAttributeTests, BadType_Output_Array) {
    // @stage(fragment)
    // fn frag_main()->@location(0) array<f32, 2> { return array<f32, 2>(); }

    Func(Source{{12, 34}}, "frag_main", {}, ty.array<f32, 2>(),
         {Return(Construct(ty.array<f32, 2>()))}, {Stage(ast::PipelineStage::kFragment)},
         {Location(Source{{34, 56}}, 0)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "12:34 error: cannot apply 'location' attribute to declaration of "
              "type 'array<f32, 2>'\n"
              "34:56 note: 'location' attribute must only be applied to "
              "declarations of numeric scalar or numeric vector type");
}

TEST_F(LocationAttributeTests, BadType_Input_Struct) {
    // struct Input {
    //   a : f32;
    // };
    // @stage(fragment)
    // fn main(@location(0) param : Input) {}
    auto* input = Structure("Input", {Member("a", ty.f32())});
    auto* param = Param(Source{{12, 34}}, "param", ty.Of(input), {Location(Source{{13, 43}}, 0)});
    Func(Source{{12, 34}}, "main", {param}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "12:34 error: cannot apply 'location' attribute to declaration of "
              "type 'Input'\n"
              "13:43 note: 'location' attribute must only be applied to "
              "declarations of numeric scalar or numeric vector type");
}

TEST_F(LocationAttributeTests, BadType_Input_Struct_NestedStruct) {
    // struct Inner {
    //   @location(0) b : f32;
    // };
    // struct Input {
    //   a : Inner;
    // };
    // @stage(fragment)
    // fn main(param : Input) {}
    auto* inner = Structure("Inner", {Member(Source{{13, 43}}, "a", ty.f32(), {Location(0)})});
    auto* input = Structure("Input", {Member(Source{{14, 52}}, "a", ty.Of(inner))});
    auto* param = Param("param", ty.Of(input));
    Func(Source{{12, 34}}, "main", {param}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "14:52 error: nested structures cannot be used for entry point IO\n"
              "12:34 note: while analysing entry point 'main'");
}

TEST_F(LocationAttributeTests, BadType_Input_Struct_RuntimeArray) {
    // struct Input {
    //   @location(0) a : array<f32>;
    // };
    // @stage(fragment)
    // fn main(param : Input) {}
    auto* input =
        Structure("Input", {Member(Source{{13, 43}}, "a", ty.array<f32>(), {Location(0)})});
    auto* param = Param("param", ty.Of(input));
    Func(Source{{12, 34}}, "main", {param}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "13:43 error: cannot apply 'location' attribute to declaration of "
              "type 'array<f32>'\n"
              "note: 'location' attribute must only be applied to declarations "
              "of numeric scalar or numeric vector type");
}

TEST_F(LocationAttributeTests, BadMemberType_Input) {
    // struct S { @location(0) m: array<i32>; };
    // @stage(fragment)
    // fn frag_main( a: S) {}

    auto* m = Member(Source{{34, 56}}, "m", ty.array<i32>(),
                     ast::AttributeList{Location(Source{{12, 34}}, 0u)});
    auto* s = Structure("S", {m});
    auto* p = Param("a", ty.Of(s));

    Func("frag_main", {p}, ty.void_(), {}, {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "34:56 error: cannot apply 'location' attribute to declaration of "
              "type 'array<i32>'\n"
              "12:34 note: 'location' attribute must only be applied to "
              "declarations of numeric scalar or numeric vector type");
}

TEST_F(LocationAttributeTests, BadMemberType_Output) {
    // struct S { @location(0) m: atomic<i32>; };
    // @stage(fragment)
    // fn frag_main() -> S {}
    auto* m = Member(Source{{34, 56}}, "m", ty.atomic<i32>(),
                     ast::AttributeList{Location(Source{{12, 34}}, 0u)});
    auto* s = Structure("S", {m});

    Func("frag_main", {}, ty.Of(s), {Return(Construct(ty.Of(s)))},
         {Stage(ast::PipelineStage::kFragment)}, {});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "34:56 error: cannot apply 'location' attribute to declaration of "
              "type 'atomic<i32>'\n"
              "12:34 note: 'location' attribute must only be applied to "
              "declarations of numeric scalar or numeric vector type");
}

TEST_F(LocationAttributeTests, BadMemberType_Unused) {
    // struct S { @location(0) m: mat3x2<f32>; };

    auto* m = Member(Source{{34, 56}}, "m", ty.mat3x2<f32>(),
                     ast::AttributeList{Location(Source{{12, 34}}, 0u)});
    Structure("S", {m});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "34:56 error: cannot apply 'location' attribute to declaration of "
              "type 'mat3x2<f32>'\n"
              "12:34 note: 'location' attribute must only be applied to "
              "declarations of numeric scalar or numeric vector type");
}

TEST_F(LocationAttributeTests, ReturnType_Struct_Valid) {
    // struct Output {
    //   @location(0) a : f32;
    //   @builtin(frag_depth) b : f32;
    // };
    // @stage(fragment)
    // fn main() -> Output {
    //   return Output();
    // }
    auto* output =
        Structure("Output", {Member("a", ty.f32(), {Location(0)}),
                             Member("b", ty.f32(), {Builtin(ast::Builtin::kFragDepth)})});
    Func(Source{{12, 34}}, "main", {}, ty.Of(output), {Return(Construct(ty.Of(output)))},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_TRUE(r()->Resolve()) << r()->error();
}

TEST_F(LocationAttributeTests, ReturnType_Struct) {
    // struct Output {
    //   a : f32;
    // };
    // @stage(vertex)
    // fn main() -> @location(0) Output {
    //   return Output();
    // }
    auto* output = Structure("Output", {Member("a", ty.f32())});
    Func(Source{{12, 34}}, "main", {}, ty.Of(output), {Return(Construct(ty.Of(output)))},
         {Stage(ast::PipelineStage::kVertex)}, {Location(Source{{13, 43}}, 0)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "12:34 error: cannot apply 'location' attribute to declaration of "
              "type 'Output'\n"
              "13:43 note: 'location' attribute must only be applied to "
              "declarations of numeric scalar or numeric vector type");
}

TEST_F(LocationAttributeTests, ReturnType_Struct_NestedStruct) {
    // struct Inner {
    //   @location(0) b : f32;
    // };
    // struct Output {
    //   a : Inner;
    // };
    // @stage(fragment)
    // fn main() -> Output { return Output(); }
    auto* inner = Structure("Inner", {Member(Source{{13, 43}}, "a", ty.f32(), {Location(0)})});
    auto* output = Structure("Output", {Member(Source{{14, 52}}, "a", ty.Of(inner))});
    Func(Source{{12, 34}}, "main", {}, ty.Of(output), {Return(Construct(ty.Of(output)))},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "14:52 error: nested structures cannot be used for entry point IO\n"
              "12:34 note: while analysing entry point 'main'");
}

TEST_F(LocationAttributeTests, ReturnType_Struct_RuntimeArray) {
    // struct Output {
    //   @location(0) a : array<f32>;
    // };
    // @stage(fragment)
    // fn main() -> Output {
    //   return Output();
    // }
    auto* output = Structure("Output", {Member(Source{{13, 43}}, "a", ty.array<f32>(),
                                               {Location(Source{{12, 34}}, 0)})});
    Func(Source{{12, 34}}, "main", {}, ty.Of(output), {Return(Construct(ty.Of(output)))},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "13:43 error: cannot apply 'location' attribute to declaration of "
              "type 'array<f32>'\n"
              "12:34 note: 'location' attribute must only be applied to "
              "declarations of numeric scalar or numeric vector type");
}

TEST_F(LocationAttributeTests, ComputeShaderLocation_Input) {
    Func("main", {}, ty.i32(), {Return(Expr(1_i))},
         {Stage(ast::PipelineStage::kCompute),
          create<ast::WorkgroupAttribute>(Source{{12, 34}}, Expr(1_i))},
         ast::AttributeList{Location(Source{{12, 34}}, 1)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), "12:34 error: attribute is not valid for compute shader output");
}

TEST_F(LocationAttributeTests, ComputeShaderLocation_Output) {
    auto* input = Param("input", ty.i32(), ast::AttributeList{Location(Source{{12, 34}}, 0u)});
    Func("main", {input}, ty.void_(), {},
         {Stage(ast::PipelineStage::kCompute),
          create<ast::WorkgroupAttribute>(Source{{12, 34}}, Expr(1_i))});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), "12:34 error: attribute is not valid for compute shader inputs");
}

TEST_F(LocationAttributeTests, ComputeShaderLocationStructMember_Output) {
    auto* m = Member("m", ty.i32(), ast::AttributeList{Location(Source{{12, 34}}, 0u)});
    auto* s = Structure("S", {m});
    Func(Source{{56, 78}}, "main", {}, ty.Of(s),
         ast::StatementList{Return(Expr(Construct(ty.Of(s))))},
         {Stage(ast::PipelineStage::kCompute),
          create<ast::WorkgroupAttribute>(Source{{12, 34}}, Expr(1_i))});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "12:34 error: attribute is not valid for compute shader output\n"
              "56:78 note: while analysing entry point 'main'");
}

TEST_F(LocationAttributeTests, ComputeShaderLocationStructMember_Input) {
    auto* m = Member("m", ty.i32(), ast::AttributeList{Location(Source{{12, 34}}, 0u)});
    auto* s = Structure("S", {m});
    auto* input = Param("input", ty.Of(s));
    Func(Source{{56, 78}}, "main", {input}, ty.void_(), {},
         {Stage(ast::PipelineStage::kCompute),
          create<ast::WorkgroupAttribute>(Source{{12, 34}}, Expr(1_i))});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "12:34 error: attribute is not valid for compute shader inputs\n"
              "56:78 note: while analysing entry point 'main'");
}

TEST_F(LocationAttributeTests, Duplicate_input) {
    // @stage(fragment)
    // fn main(@location(1) param_a : f32,
    //         @location(1) param_b : f32) {}
    auto* param_a = Param("param_a", ty.f32(), {Location(1)});
    auto* param_b = Param("param_b", ty.f32(), {Location(Source{{12, 34}}, 1)});
    Func(Source{{12, 34}}, "main", {param_a, param_b}, ty.void_(), {},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(), "12:34 error: location(1) attribute appears multiple times");
}

TEST_F(LocationAttributeTests, Duplicate_struct) {
    // struct InputA {
    //   @location(1) a : f32;
    // };
    // struct InputB {
    //   @location(1) a : f32;
    // };
    // @stage(fragment)
    // fn main(param_a : InputA, param_b : InputB) {}
    auto* input_a = Structure("InputA", {Member("a", ty.f32(), {Location(1)})});
    auto* input_b = Structure("InputB", {Member("a", ty.f32(), {Location(Source{{34, 56}}, 1)})});
    auto* param_a = Param("param_a", ty.Of(input_a));
    auto* param_b = Param("param_b", ty.Of(input_b));
    Func(Source{{12, 34}}, "main", {param_a, param_b}, ty.void_(), {},
         {Stage(ast::PipelineStage::kFragment)});

    EXPECT_FALSE(r()->Resolve());
    EXPECT_EQ(r()->error(),
              "34:56 error: location(1) attribute appears multiple times\n"
              "12:34 note: while analysing entry point 'main'");
}

}  // namespace
}  // namespace LocationAttributeTests

}  // namespace
}  // namespace tint::resolver