Help+man+LibManual: Move argument handling to LibManual

This deduplicates argument handling logic from Help and man and makes it
more modular for future use cases. The argument handling works as
before: two arguments specify section and page (in this order), one
argument specifies either a page (the first section that it's found in
is used) or a path to a manpage markdown file.

1 files changed, 20 insertions, 45 deletions

diff --git a/Userland/Applications/Help/main.cpp b/Userland/Applications/Help/main.cpp
index 3ae157664b..ec4c867387 100644
--- a/Userland/Applications/Help/main.cpp
+++ b/Userland/Applications/Help/main.cpp
@@ -2,6 +2,7 @@
  * Copyright (c) 2019-2020, Sergey Bugaev <bugaevc@serenityos.org>
  * Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
  * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, kleines Filmröllchen <filmroellchen@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -17,15 +18,6 @@
 
 using namespace Help;
 
-static DeprecatedString parse_input(StringView input)
-{
-    AK::URL url = URL::create_with_url_or_path(input);
-    if (url.is_valid())
-        return url.basename();
-
-    return input;
-}
-
 ErrorOr<int> serenity_main(Main::Arguments arguments)
 {
     TRY(Core::System::pledge("stdio recvfd sendfd rpath unix"));
@@ -40,44 +32,27 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     TRY(Core::System::unveil("/tmp/session/%sid/portal/webcontent", "rw"));
     TRY(Core::System::unveil(nullptr, nullptr));
 
-    DeprecatedString start_page;
-    u32 section = 0;
+    DeprecatedString first_query_parameter;
+    DeprecatedString second_query_parameter;
 
     Core::ArgsParser args_parser;
-    // FIXME: These custom Args are a hack. What we want to do is have an optional int arg, then an optional string.
-    // However, when only a string is provided, it gets forwarded to the int argument since that is first, and
-    // parsing fails. This hack instead forwards it to the start_page in that case.
-    args_parser.add_positional_argument(Core::ArgsParser::Arg {
-        .help_string = "Section of the man page",
-        .name = "section",
-        .min_values = 0,
-        .max_values = 1,
-        .accept_value = [&](char const* input_ptr) {
-            StringView input { input_ptr, strlen(input_ptr) };
-            // If it's a number, use it as the section
-            if (auto number = input.to_int(); number.has_value()) {
-                section = number.value();
-                return true;
-            }
-
-            // Otherwise, use it as the start_page
-            start_page = parse_input(input);
-            return true;
-        } });
-    args_parser.add_positional_argument(Core::ArgsParser::Arg {
-        .help_string = "Help page to open. Either an absolute path to the markdown file, or a search query",
-        .name = "page",
-        .min_values = 0,
-        .max_values = 1,
-        .accept_value = [&](char const* input_ptr) {
-            StringView input { input_ptr, strlen(input_ptr) };
-            // If start_page was already set by our section arg, then it can't be set again
-            if (!start_page.is_empty())
-                return false;
-            start_page = parse_input(input);
-            return true;
-        } });
+    // The actual "page query" parsing happens when we set the main widget's start page.
+    args_parser.add_positional_argument(
+        first_query_parameter,
+        "Section of the man page",
+        "section",
+        Core::ArgsParser::Required::No);
+    args_parser.add_positional_argument(
+        second_query_parameter,
+        "Help page to open. Either an absolute path to the markdown file, or a search query",
+        "page",
+        Core::ArgsParser::Required::No);
     args_parser.parse(arguments);
+    Vector<StringView, 2> query_parameters;
+    if (!first_query_parameter.is_empty())
+        query_parameters.append(first_query_parameter);
+    if (!second_query_parameter.is_empty())
+        query_parameters.append(second_query_parameter);
 
     auto app_icon = GUI::Icon::default_icon("app-help"sv);
 
@@ -88,7 +63,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
 
     auto main_widget = TRY(window->try_set_main_widget<MainWidget>());
     TRY(main_widget->initialize_fallibles(window));
-    TRY(main_widget->set_start_page(start_page, section));
+    TRY(main_widget->set_start_page(query_parameters));
 
     window->show();