integrate hotkeys with helpdb

plugins/CMakeLists.txt

@@ -130,7 +130,7 @@ if(BUILD_SUPPORTED)
     dfhack_plugin(forceequip forceequip.cpp)
     dfhack_plugin(generated-creature-renamer generated-creature-renamer.cpp)
     dfhack_plugin(getplants getplants.cpp)
-    dfhack_plugin(hotkeys hotkeys.cpp)
+    dfhack_plugin(hotkeys hotkeys.cpp LINK_LIBRARIES lua)
     dfhack_plugin(infiniteSky infiniteSky.cpp)
     dfhack_plugin(isoworldremote isoworldremote.cpp PROTOBUFS isoworldremote)
     dfhack_plugin(jobutils jobutils.cpp)

plugins/hotkeys.cpp

@@ -8,6 +8,7 @@
 #include "modules/World.h"
 #include "modules/Gui.h"
 
+#include "LuaTools.h"
 #include "PluginManager.h"
 
 DFHACK_PLUGIN("hotkeys");
@@ -54,6 +55,8 @@ static void find_active_keybindings(df::viewscreen *screen)
         valid_keys.push_back("F" + int_to_string(i));
     }
 
+    valid_keys.push_back("`");
+
     auto current_focus = Gui::getFocusString(screen);
     for (int shifted = 0; shifted < 2; shifted++)
     {
@@ -120,6 +123,29 @@ static void invoke_command(const size_t index)
     }
 }
 
+static std::string get_help(const std::string &command, bool full_help)
+{
+    auto L = Lua::Core::State;
+    color_ostream_proxy out(Core::getInstance().getConsole());
+    Lua::StackUnwinder top(L);
+
+    if (!lua_checkstack(L, 2) ||
+        !Lua::PushModulePublic(out, L, "helpdb",
+                    full_help ? "get_entry_long_help" : "get_entry_short_help"))
+        return "Help text unavailable.";
+
+    Lua::Push(L, command);
+
+    if (!Lua::SafeCall(out, L, 1, 1))
+        return "Help text unavailable.";
+
+    const char *s = lua_tostring(L, -1);
+    if (!s)
+        return "Help text unavailable.";
+
+    return s;
+}
+
 class ViewscreenHotkeys : public dfhack_viewscreen
 {
 public:
@@ -219,20 +245,9 @@ public:
         if (first[0] == '#')
             return;
 
-        Plugin *plugin = Core::getInstance().getPluginManager()->getPluginByCommand(first);
-        if (plugin)
-        {
-            for (size_t i = 0; i < plugin->size(); i++)
-            {
-                auto pc = plugin->operator[](i);
-                if (pc.name == first)
-                {
         OutputString(COLOR_BROWN, x, y, "Help", true, help_start);
+        string help_text = get_help(first, show_usage);
         vector <string> lines;
-                    string help_text = pc.description;
-                    if (show_usage)
-                        help_text += "\n\n" + pc.usage;
-
         split_string(&lines, help_text, "\n");
         for (auto it = lines.begin(); it != lines.end() && y < gps->dimy - 4; it++)
         {
@@ -242,10 +257,6 @@ public:
                 OutputString(COLOR_WHITE, x, y, *wit, true, help_start);
             }
         }
-                    break;
-                }
-            }
-        }
     }
 
     virtual std::string getFocusString()