// 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 "gmock/gmock.h"
#include "src/tint/ast/variable_decl_statement.h"
#include "src/tint/writer/glsl/test_helper.h"

namespace tint::writer::glsl {
namespace {

using ::testing::HasSubstr;

using GlslGeneratorImplTest_VariableDecl = TestHelper;

TEST_F(GlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement) {
    auto* var = Var("a", ty.f32());
    auto* stmt = Decl(var);
    WrapInFunction(stmt);

    GeneratorImpl& gen = Build();

    gen.increment_indent();

    ASSERT_TRUE(gen.EmitStatement(stmt)) << gen.error();
    EXPECT_EQ(gen.result(), "  float a = 0.0f;\n");
}

TEST_F(GlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement_Const) {
    auto* var = Let("a", ty.f32(), Construct(ty.f32()));
    auto* stmt = Decl(var);
    WrapInFunction(stmt);

    GeneratorImpl& gen = Build();

    gen.increment_indent();

    ASSERT_TRUE(gen.EmitStatement(stmt)) << gen.error();
    EXPECT_EQ(gen.result(), "  float a = 0.0f;\n");
}

TEST_F(GlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement_Array) {
    auto* var = Var("a", ty.array<f32, 5>());

    WrapInFunction(var, Expr("a"));

    GeneratorImpl& gen = Build();

    gen.increment_indent();

    ASSERT_TRUE(gen.Generate()) << gen.error();
    EXPECT_THAT(gen.result(),
                HasSubstr("  float a[5] = float[5](0.0f, 0.0f, 0.0f, 0.0f, 0.0f);\n"));
}

TEST_F(GlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement_Private) {
    Global("a", ty.f32(), ast::StorageClass::kPrivate);

    WrapInFunction(Expr("a"));

    GeneratorImpl& gen = Build();

    gen.increment_indent();

    ASSERT_TRUE(gen.Generate()) << gen.error();
    EXPECT_THAT(gen.result(), HasSubstr("  float a = 0.0f;\n"));
}

TEST_F(GlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement_Initializer_Private) {
    Global("initializer", ty.f32(), ast::StorageClass::kPrivate);
    Global("a", ty.f32(), ast::StorageClass::kPrivate, Expr("initializer"));

    WrapInFunction(Expr("a"));

    GeneratorImpl& gen = Build();

    ASSERT_TRUE(gen.Generate()) << gen.error();
    EXPECT_THAT(gen.result(), HasSubstr(R"(float a = initializer;
)"));
}

TEST_F(GlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement_Initializer_ZeroVec) {
    auto* var = Var("a", ty.vec3<f32>(), ast::StorageClass::kNone, vec3<f32>());

    auto* stmt = Decl(var);
    WrapInFunction(stmt);

    GeneratorImpl& gen = Build();

    ASSERT_TRUE(gen.EmitStatement(stmt)) << gen.error();
    EXPECT_EQ(gen.result(), R"(vec3 a = vec3(0.0f);
)");
}

TEST_F(GlslGeneratorImplTest_VariableDecl, Emit_VariableDeclStatement_Initializer_ZeroMat) {
    auto* var = Var("a", ty.mat2x3<f32>(), ast::StorageClass::kNone, mat2x3<f32>());

    auto* stmt = Decl(var);
    WrapInFunction(stmt);

    GeneratorImpl& gen = Build();

    ASSERT_TRUE(gen.EmitStatement(stmt)) << gen.error();
    EXPECT_EQ(gen.result(),
              R"(mat2x3 a = mat2x3(vec3(0.0f), vec3(0.0f));
)");
}

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