// 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/reader/wgsl/parser_impl_test_helper.h"

namespace tint::reader::wgsl {
namespace {

TEST_F(ParserImplTest, GlobalDecl_Semicolon) {
    auto p = parser(";");
    p->global_decl();
    ASSERT_FALSE(p->has_error()) << p->error();
}

TEST_F(ParserImplTest, GlobalDecl_GlobalVariable) {
    auto p = parser("var<private> a : vec2<i32> = vec2<i32>(1, 2);");
    p->global_decl();
    ASSERT_FALSE(p->has_error()) << p->error();

    auto program = p->program();
    ASSERT_EQ(program.AST().GlobalVariables().size(), 1u);

    auto* v = program.AST().GlobalVariables()[0];
    EXPECT_EQ(v->symbol, program.Symbols().Get("a"));
}

TEST_F(ParserImplTest, GlobalDecl_GlobalVariable_Inferred_Invalid) {
    auto p = parser("var<private> a = vec2<i32>(1, 2);");
    p->global_decl();
    ASSERT_TRUE(p->has_error());
    EXPECT_EQ(p->error(), "1:16: expected ':' for variable declaration");
}

TEST_F(ParserImplTest, GlobalDecl_GlobalVariable_MissingSemicolon) {
    auto p = parser("var<private> a : vec2<i32>");
    p->global_decl();
    ASSERT_TRUE(p->has_error());
    EXPECT_EQ(p->error(), "1:27: expected ';' for variable declaration");
}

TEST_F(ParserImplTest, GlobalDecl_GlobalConstant) {
    auto p = parser("let a : i32 = 2;");
    p->global_decl();
    ASSERT_FALSE(p->has_error()) << p->error();

    auto program = p->program();
    ASSERT_EQ(program.AST().GlobalVariables().size(), 1u);

    auto* v = program.AST().GlobalVariables()[0];
    EXPECT_EQ(v->symbol, program.Symbols().Get("a"));
}

TEST_F(ParserImplTest, GlobalDecl_GlobalConstant_MissingInitializer) {
    auto p = parser("let a : vec2<i32>;");
    p->global_decl();
    ASSERT_TRUE(p->has_error());
    EXPECT_EQ(p->error(), "1:18: expected '=' for 'let' declaration");
}

TEST_F(ParserImplTest, GlobalDecl_GlobalConstant_Invalid) {
    auto p = parser("let a : vec2<i32> 1.0;");
    p->global_decl();
    ASSERT_TRUE(p->has_error());
    EXPECT_EQ(p->error(), "1:19: expected '=' for 'let' declaration");
}

TEST_F(ParserImplTest, GlobalDecl_GlobalConstant_MissingSemicolon) {
    auto p = parser("let a : vec2<i32> = vec2<i32>(1, 2)");
    p->global_decl();
    ASSERT_TRUE(p->has_error());
    EXPECT_EQ(p->error(), "1:36: expected ';' for 'let' declaration");
}

TEST_F(ParserImplTest, GlobalDecl_TypeAlias) {
    auto p = parser("type A = i32;");
    p->global_decl();
    ASSERT_FALSE(p->has_error()) << p->error();

    auto program = p->program();
    ASSERT_EQ(program.AST().TypeDecls().size(), 1u);
    ASSERT_TRUE(program.AST().TypeDecls()[0]->Is<ast::Alias>());
    EXPECT_EQ(program.Symbols().NameFor(program.AST().TypeDecls()[0]->As<ast::Alias>()->name), "A");
}

TEST_F(ParserImplTest, GlobalDecl_TypeAlias_StructIdent) {
    auto p = parser(R"(struct A {
  a : f32,
}
type B = A;)");
    p->global_decl();
    p->global_decl();
    ASSERT_FALSE(p->has_error()) << p->error();

    auto program = p->program();
    ASSERT_EQ(program.AST().TypeDecls().size(), 2u);
    ASSERT_TRUE(program.AST().TypeDecls()[0]->Is<ast::Struct>());
    auto* str = program.AST().TypeDecls()[0]->As<ast::Struct>();
    EXPECT_EQ(str->name, program.Symbols().Get("A"));

    ASSERT_TRUE(program.AST().TypeDecls()[1]->Is<ast::Alias>());
    auto* alias = program.AST().TypeDecls()[1]->As<ast::Alias>();
    EXPECT_EQ(alias->name, program.Symbols().Get("B"));
    auto* tn = alias->type->As<ast::TypeName>();
    EXPECT_NE(tn, nullptr);
    EXPECT_EQ(tn->name, str->name);
}

TEST_F(ParserImplTest, GlobalDecl_TypeAlias_MissingSemicolon) {
    auto p = parser("type A = i32");
    p->global_decl();
    ASSERT_TRUE(p->has_error());
    EXPECT_EQ(p->error(), "1:13: expected ';' for type alias");
}

TEST_F(ParserImplTest, GlobalDecl_Function) {
    auto p = parser("fn main() { return; }");
    p->global_decl();
    ASSERT_FALSE(p->has_error()) << p->error();

    auto program = p->program();
    ASSERT_EQ(program.AST().Functions().size(), 1u);
    EXPECT_EQ(program.Symbols().NameFor(program.AST().Functions()[0]->symbol), "main");
}

TEST_F(ParserImplTest, GlobalDecl_Function_WithAttribute) {
    auto p = parser("@workgroup_size(2) fn main() { return; }");
    p->global_decl();
    ASSERT_FALSE(p->has_error()) << p->error();

    auto program = p->program();
    ASSERT_EQ(program.AST().Functions().size(), 1u);
    EXPECT_EQ(program.Symbols().NameFor(program.AST().Functions()[0]->symbol), "main");
}

TEST_F(ParserImplTest, GlobalDecl_Function_Invalid) {
    auto p = parser("fn main() -> { return; }");
    p->global_decl();
    ASSERT_TRUE(p->has_error());
    EXPECT_EQ(p->error(), "1:14: unable to determine function return type");
}

TEST_F(ParserImplTest, GlobalDecl_ParsesStruct) {
    auto p = parser("struct A { b: i32, c: f32}");
    p->global_decl();
    ASSERT_FALSE(p->has_error()) << p->error();

    auto program = p->program();
    ASSERT_EQ(program.AST().TypeDecls().size(), 1u);

    auto* t = program.AST().TypeDecls()[0];
    ASSERT_NE(t, nullptr);
    ASSERT_TRUE(t->Is<ast::Struct>());

    auto* str = t->As<ast::Struct>();
    EXPECT_EQ(str->name, program.Symbols().Get("A"));
    EXPECT_EQ(str->members.size(), 2u);
}

TEST_F(ParserImplTest, GlobalDecl_Struct_Invalid) {
    {
        auto p = parser("A {}");
        auto decl = p->global_decl();
        // global_decl will result in a no match.
        ASSERT_FALSE(p->has_error()) << p->error();
        ASSERT_TRUE(!decl.matched && !decl.errored);
    }
    {
        auto p = parser("A {}");
        p->translation_unit();
        // translation_unit will result in a general error.
        ASSERT_TRUE(p->has_error());
        EXPECT_EQ(p->error(), "1:1: unexpected token");
    }
}

}  // namespace
}  // namespace tint::reader::wgsl