LibWeb: Add code generator for CSS transform functions

This first step just generates the TransformFunction enum, but more will
follow.

2 files changed, 93 insertions, 0 deletions

diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/CMakeLists.txt b/Meta/Lagom/Tools/CodeGenerators/LibWeb/CMakeLists.txt
index 7b3e7904e7..df45d28635 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/CMakeLists.txt
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/CMakeLists.txt
@@ -3,6 +3,7 @@ set(SOURCES "") # avoid pulling SOURCES from parent scope
 lagom_tool(GenerateCSSEnums                SOURCES GenerateCSSEnums.cpp LIBS LagomMain)
 lagom_tool(GenerateCSSMediaFeatureID       SOURCES GenerateCSSMediaFeatureID.cpp LIBS LagomMain)
 lagom_tool(GenerateCSSPropertyID           SOURCES GenerateCSSPropertyID.cpp LIBS LagomMain)
+lagom_tool(GenerateCSSTransformFunctions   SOURCES GenerateCSSTransformFunctions.cpp LIBS LagomMain)
 lagom_tool(GenerateCSSValueID              SOURCES GenerateCSSValueID.cpp LIBS LagomMain)
 
 add_subdirectory(WrapperGenerator)
diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSTransformFunctions.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSTransformFunctions.cpp
new file mode 100644
index 0000000000..31f6c16e80
--- /dev/null
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSTransformFunctions.cpp
@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2022, Sam Atkins <atkinssj@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "GeneratorUtil.h"
+#include <AK/SourceGenerator.h>
+#include <AK/StringBuilder.h>
+#include <LibCore/ArgsParser.h>
+#include <LibMain/Main.h>
+
+ErrorOr<void> generate_header_file(JsonObject& transforms_data, Core::Stream::File& file);
+ErrorOr<void> generate_implementation_file(JsonObject& transforms_data, Core::Stream::File& file);
+
+ErrorOr<int> serenity_main(Main::Arguments arguments)
+{
+    StringView generated_header_path;
+    StringView generated_implementation_path;
+    StringView identifiers_json_path;
+
+    Core::ArgsParser args_parser;
+    args_parser.add_option(generated_header_path, "Path to the TransformFunctions header file to generate", "generated-header-path", 'h', "generated-header-path");
+    args_parser.add_option(generated_implementation_path, "Path to the TransformFunctions implementation file to generate", "generated-implementation-path", 'c', "generated-implementation-path");
+    args_parser.add_option(identifiers_json_path, "Path to the JSON file to read from", "json-path", 'j', "json-path");
+    args_parser.parse(arguments);
+
+    auto json = TRY(read_entire_file_as_json(identifiers_json_path));
+    VERIFY(json.is_object());
+    auto transforms_data = json.as_object();
+
+    auto generated_header_file = TRY(Core::Stream::File::open(generated_header_path, Core::Stream::OpenMode::Write));
+    auto generated_implementation_file = TRY(Core::Stream::File::open(generated_implementation_path, Core::Stream::OpenMode::Write));
+
+    TRY(generate_header_file(transforms_data, *generated_header_file));
+    TRY(generate_implementation_file(transforms_data, *generated_implementation_file));
+
+    return 0;
+}
+
+static String title_casify_transform_function(StringView input)
+{
+    // Transform function names look like `fooBar`, so we just have to make the first character uppercase.
+    StringBuilder builder;
+    builder.append(toupper(input[0]));
+    builder.append(input.substring_view(1));
+    return builder.to_string();
+}
+
+ErrorOr<void> generate_header_file(JsonObject& transforms_data, Core::Stream::File& file)
+{
+    StringBuilder builder;
+    SourceGenerator generator { builder };
+
+    generator.append(R"~~~(
+namespace Web::CSS {
+
+)~~~");
+
+    generator.appendln("enum class TransformFunction {");
+    transforms_data.for_each_member([&](auto& name, auto&) {
+        auto member_generator = generator.fork();
+        member_generator.set("name:titlecase", title_casify_transform_function(name));
+        member_generator.appendln("    @name:titlecase@,");
+    });
+    generator.appendln("};");
+
+    generator.appendln("\n}");
+
+    TRY(file.write(generator.as_string_view().bytes()));
+    return {};
+}
+
+ErrorOr<void> generate_implementation_file(JsonObject& transforms_data, Core::Stream::File& file)
+{
+    StringBuilder builder;
+    SourceGenerator generator { builder };
+
+    generator.append(R"~~~(
+namespace Web::CSS {
+)~~~");
+
+    transforms_data.for_each_member([&](auto& name, auto& value) {
+        (void)name;
+        (void)value;
+    });
+
+    generator.appendln("}");
+
+    TRY(file.write(generator.as_string_view().bytes()));
+    return {};
+}