LibUncode: Parse and generate emoji code point data

According to TR #51, the "best definition of the full set [of emojis] is
in the emoji-test.txt file". This defines not only the emoji themselves,
but the order in which they should be displayed, and what "group" of
emojis they belong to.

Meta/Lagom/Tools/CodeGenerators/LibUnicode/GenerateEmojiData.cpp

@@ -0,0 +1,220 @@
+/*
+ * Copyright (c) 2022, Tim Flynn <trflynn89@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "GeneratorUtil.h"
+#include <AK/SourceGenerator.h>
+#include <AK/String.h>
+#include <AK/StringUtils.h>
+#include <AK/Types.h>
+#include <LibCore/ArgsParser.h>
+#include <LibCore/Stream.h>
+#include <LibUnicode/Emoji.h>
+
+using StringIndexType = u16;
+constexpr auto s_string_index_type = "u16"sv;
+
+struct Emoji {
+    StringIndexType name { 0 };
+    Unicode::EmojiGroup group;
+    u32 display_order { 0 };
+    String code_points_name;
+    Vector<u32> code_points;
+};
+
+struct EmojiData {
+    UniqueStringStorage<StringIndexType> unique_strings;
+    Vector<Emoji> emojis;
+};
+
+static ErrorOr<void> parse_emoji_test_data(Core::Stream::BufferedFile& file, EmojiData& emoji_data)
+{
+    static constexpr auto group_header = "# group: "sv;
+
+    Array<u8, 1024> buffer;
+
+    Unicode::EmojiGroup group;
+    u32 display_order { 0 };
+
+    while (TRY(file.can_read_line())) {
+        auto line = TRY(file.read_line(buffer));
+        if (line.is_empty())
+            continue;
+
+        if (line.starts_with('#')) {
+            if (line.starts_with(group_header)) {
+                auto name = line.substring_view(group_header.length());
+                group = Unicode::emoji_group_from_string(name);
+            }
+
+            continue;
+        }
+
+        auto status_index = line.find(';');
+        VERIFY(status_index.has_value());
+
+        auto emoji_and_name_index = line.find('#', *status_index);
+        VERIFY(emoji_and_name_index.has_value());
+
+        // FIXME: Should we keep non-fully-qualified emoji? TR #51 states this is implementation defined.
+        auto status = line.substring_view(*status_index + 1, *emoji_and_name_index - *status_index - 1).trim_whitespace();
+        if (status != "fully-qualified"sv)
+            continue;
+
+        Emoji emoji {};
+        emoji.group = group;
+        emoji.display_order = display_order++;
+
+        auto code_points = line.substring_view(0, *status_index).split_view(' ');
+        TRY(emoji.code_points.try_ensure_capacity(code_points.size()));
+
+        for (auto code_point : code_points) {
+            auto value = AK::StringUtils::convert_to_uint_from_hex<u32>(code_point);
+            VERIFY(value.has_value());
+
+            emoji.code_points.unchecked_append(*value);
+        }
+
+        auto emoji_and_name = line.substring_view(*emoji_and_name_index + 1);
+
+        auto emoji_and_name_spaces = emoji_and_name.find_all(" "sv);
+        VERIFY(emoji_and_name_spaces.size() > 2);
+
+        auto name = emoji_and_name.substring_view(emoji_and_name_spaces[2]).trim_whitespace();
+        emoji.name = emoji_data.unique_strings.ensure(name.to_titlecase_string());
+        emoji.code_points_name = String::join('_', code_points);
+
+        TRY(emoji_data.emojis.try_append(move(emoji)));
+    }
+
+    return {};
+}
+
+static ErrorOr<void> generate_emoji_data_header(Core::Stream::BufferedFile& file, EmojiData const&)
+{
+    StringBuilder builder;
+    SourceGenerator generator { builder };
+
+    TRY(file.write(generator.as_string_view().bytes()));
+    return {};
+}
+
+static ErrorOr<void> generate_emoji_data_implementation(Core::Stream::BufferedFile& file, EmojiData const& emoji_data)
+{
+    StringBuilder builder;
+    SourceGenerator generator { builder };
+
+    generator.set("string_index_type"sv, s_string_index_type);
+    generator.set("emojis_size"sv, String::number(emoji_data.emojis.size()));
+
+    generator.append(R"~~~(
+#include <AK/Array.h>
+#include <AK/BinarySearch.h>
+#include <AK/Span.h>
+#include <AK/StringView.h>
+#include <AK/Types.h>
+#include <LibUnicode/Emoji.h>
+#include <LibUnicode/EmojiData.h>
+
+namespace Unicode {
+)~~~");
+
+    emoji_data.unique_strings.generate(generator);
+
+    generator.append(R"~~~(
+struct EmojiData {
+    constexpr Emoji to_unicode_emoji() const
+    {
+        Emoji emoji {};
+        emoji.name = decode_string(name);
+        emoji.group = static_cast<EmojiGroup>(group);
+        emoji.display_order = display_order;
+        emoji.code_points = code_points;
+
+        return emoji;
+    }
+
+    @string_index_type@ name { 0 };
+    u8 group { 0 };
+    u32 display_order { 0 };
+    Span<u32 const> code_points;
+};
+)~~~");
+
+    for (auto const& emoji : emoji_data.emojis) {
+        generator.set("name"sv, emoji.code_points_name);
+        generator.set("size"sv, String::number(emoji.code_points.size()));
+
+        generator.append(R"~~~(
+static constexpr Array<u32, @size@> s_@name@ { {)~~~");
+
+        bool first = true;
+        for (auto code_point : emoji.code_points) {
+            generator.append(first ? " "sv : ", "sv);
+            generator.append(String::formatted("{:#x}", code_point));
+            first = false;
+        }
+
+        generator.append(" } };"sv);
+    }
+
+    generator.append(R"~~~(
+
+static constexpr Array<EmojiData, @emojis_size@> s_emojis { {)~~~");
+
+    for (auto const& emoji : emoji_data.emojis) {
+        generator.set("name"sv, String::number(emoji.name));
+        generator.set("group"sv, String::number(to_underlying(emoji.group)));
+        generator.set("display_order"sv, String::number(emoji.display_order));
+        generator.set("code_points_name"sv, emoji.code_points_name);
+
+        generator.append(R"~~~(
+    { @name@, @group@, @display_order@, s_@code_points_name@ },)~~~");
+    }
+
+    generator.append(R"~~~(
+} };
+
+Optional<Emoji> find_emoji_for_code_points(Span<u32 const> code_points)
+{
+    for (auto& emoji : s_emojis) {
+        if (emoji.code_points == code_points)
+            return emoji.to_unicode_emoji();
+    }
+
+    return {};
+}
+
+}
+)~~~");
+
+    TRY(file.write(generator.as_string_view().bytes()));
+    return {};
+}
+
+ErrorOr<int> serenity_main(Main::Arguments arguments)
+{
+    StringView generated_header_path;
+    StringView generated_implementation_path;
+    StringView emoji_test_path;
+
+    Core::ArgsParser args_parser;
+    args_parser.add_option(generated_header_path, "Path to the Unicode Data header file to generate", "generated-header-path", 'h', "generated-header-path");
+    args_parser.add_option(generated_implementation_path, "Path to the Unicode Data implementation file to generate", "generated-implementation-path", 'c', "generated-implementation-path");
+    args_parser.add_option(emoji_test_path, "Path to emoji-test.txt file", "emoji-test-path", 'e', "emoji-test-path");
+    args_parser.parse(arguments);
+
+    auto generated_header_file = TRY(open_file(generated_header_path, Core::Stream::OpenMode::Write));
+    auto generated_implementation_file = TRY(open_file(generated_implementation_path, Core::Stream::OpenMode::Write));
+    auto emoji_test_file = TRY(open_file(emoji_test_path, Core::Stream::OpenMode::Read));
+
+    EmojiData emoji_data {};
+    TRY(parse_emoji_test_data(*emoji_test_file, emoji_data));
+
+    TRY(generate_emoji_data_header(*generated_header_file, emoji_data));
+    TRY(generate_emoji_data_implementation(*generated_implementation_file, emoji_data));
+
+    return 0;
+}