Use a struct for arguments and nested map for categories

Instead of a single map with the category and name as the key,
make m_available_args contain maps. The key will be the category and
the value is a map which actually contains the arguments for that
category. The nested map's key is the argument name, while the value
is a struct that contains the help text and whether the argument is
a debug only argument.

Author: achow101

src/util.cpp

@@ -549,48 +549,80 @@ void ArgsManager::ForceSetArg(const std::string& strArg, const std::string& strV
 
 void ArgsManager::AddArg(const std::string& name, const std::string& help, const bool debug_only, const OptionsCategory& cat)
 {
-    std::pair<OptionsCategory, std::string> key(cat, name);
-    assert(m_available_args.count(key) == 0);
-    m_available_args.emplace(key, std::pair<std::string, bool>(help, debug_only));
+    // Split arg name from its help param
+    size_t eq_index = name.find('=');
+    if (eq_index == std::string::npos) {
+        eq_index = name.size();
+    }
+
+    std::map<std::string, Arg>& arg_map = m_available_args[cat];
+    auto ret = arg_map.emplace(name.substr(0, eq_index), Arg(name.substr(eq_index, name.size() - eq_index), help, debug_only));
+    assert(ret.second); // Make sure an insertion actually happened
 }
 
 std::string ArgsManager::GetHelpMessage()
 {
     const bool show_debug = gArgs.GetBoolArg("-help-debug", false);
 
-    std::string usage = HelpMessageGroup("Options:");
-
-    OptionsCategory last_cat = OptionsCategory::OPTIONS;
-    for (auto& arg : m_available_args) {
-        if (arg.first.first != last_cat) {
-            last_cat = arg.first.first;
-            if (last_cat == OptionsCategory::CONNECTION)
+    std::string usage = "";
+    for (const auto& arg_map : m_available_args) {
+        switch(arg_map.first) {
+            case OptionsCategory::OPTIONS:
+                usage += HelpMessageGroup("Options:");
+                break;
+            case OptionsCategory::CONNECTION:
                 usage += HelpMessageGroup("Connection options:");
-            else if (last_cat == OptionsCategory::ZMQ)
+                break;
+            case OptionsCategory::ZMQ:
                 usage += HelpMessageGroup("ZeroMQ notification options:");
-            else if (last_cat == OptionsCategory::DEBUG_TEST)
+                break;
+            case OptionsCategory::DEBUG_TEST:
                 usage += HelpMessageGroup("Debugging/Testing options:");
-            else if (last_cat == OptionsCategory::NODE_RELAY)
+                break;
+            case OptionsCategory::NODE_RELAY:
                 usage += HelpMessageGroup("Node relay options:");
-            else if (last_cat == OptionsCategory::BLOCK_CREATION)
+                break;
+            case OptionsCategory::BLOCK_CREATION:
                 usage += HelpMessageGroup("Block creation options:");
-            else if (last_cat == OptionsCategory::RPC)
+                break;
+            case OptionsCategory::RPC:
                 usage += HelpMessageGroup("RPC server options:");
-            else if (last_cat == OptionsCategory::WALLET)
+                break;
+            case OptionsCategory::WALLET:
                 usage += HelpMessageGroup("Wallet options:");
-            else if (last_cat == OptionsCategory::WALLET_DEBUG_TEST && show_debug)
-                usage += HelpMessageGroup("Wallet debugging/testing options:");
-            else if (last_cat == OptionsCategory::CHAINPARAMS)
+                break;
+            case OptionsCategory::WALLET_DEBUG_TEST:
+                if (show_debug) usage += HelpMessageGroup("Wallet debugging/testing options:");
+                break;
+            case OptionsCategory::CHAINPARAMS:
                 usage += HelpMessageGroup("Chain selection options:");
-            else if (last_cat == OptionsCategory::GUI)
+                break;
+            case OptionsCategory::GUI:
                 usage += HelpMessageGroup("UI Options:");
-            else if (last_cat == OptionsCategory::COMMANDS)
+                break;
+            case OptionsCategory::COMMANDS:
                 usage += HelpMessageGroup("Commands:");
-            else if (last_cat == OptionsCategory::REGISTER_COMMANDS)
+                break;
+            case OptionsCategory::REGISTER_COMMANDS:
                 usage += HelpMessageGroup("Register Commands:");
+                break;
+            default:
+                break;
         }
-        if (show_debug || !arg.second.second) {
-            usage += HelpMessageOpt(arg.first.second, arg.second.first);
+
+        // When we get to the hidden options, stop
+        if (arg_map.first == OptionsCategory::HIDDEN) break;
+
+        for (const auto& arg : arg_map.second) {
+            if (show_debug || !arg.second.m_debug_only) {
+                std::string name;
+                if (arg.second.m_help_param.empty()) {
+                    name = arg.first;
+                } else {
+                    name = arg.first + arg.second.m_help_param;
+                }
+                usage += HelpMessageOpt(name, arg.second.m_help_text);
+            }
         }
     }
     return usage;

src/util.h

@@ -140,12 +140,21 @@ class ArgsManager
 protected:
     friend class ArgsManagerHelper;
 
+    struct Arg
+    {
+        std::string m_help_param;
+        std::string m_help_text;
+        bool m_debug_only;
+
+        Arg(const std::string& help_param, const std::string& help_text, bool debug_only) : m_help_param(help_param), m_help_text(help_text), m_debug_only(debug_only) {};
+    };
+
     mutable CCriticalSection cs_args;
     std::map<std::string, std::vector<std::string>> m_override_args;
     std::map<std::string, std::vector<std::string>> m_config_args;
     std::string m_network;
     std::set<std::string> m_network_only_args;
-    std::map<std::pair<OptionsCategory, std::string>, std::pair<std::string, bool>> m_available_args;
+    std::map<OptionsCategory, std::map<std::string, Arg>> m_available_args;
 
     void ReadConfigStream(std::istream& stream);