Implement VMF Package Manager (#29)

vmf/scripts/mods/vmf/modules/vmf_mod_manager.lua

@@ -116,6 +116,14 @@ function vmf.initialize_mod_data(mod, mod_data)
   vmf.set_internal_data(mod, "is_mutator",      mod_data.is_mutator)
   vmf.set_internal_data(mod, "allow_rehooking", mod_data.allow_rehooking)
 
+  local mod_manager = Managers.mod
+  local current_mod_load_index = mod_manager._mod_load_index
+  if current_mod_load_index then
+    vmf.set_internal_data(mod, "mod_handle", mod_manager._mods[current_mod_load_index].handle)
+  else
+    mod:warning("Could not determine current mod load index. Package management won't be available for this mod.")
+  end
+
   -- Register mod as mutator @TODO: calling this after options initialization would be better, I guess?
   if mod_data.is_mutator then
     vmf.register_mod_as_mutator(mod, mod_data.mutator_settings)
@@ -163,4 +171,4 @@ end
 -- VARIABLES
 
 vmf.mods = _mods
-vmf.mods_unloading_order = _mods_unloading_order
+vmf.mods_unloading_order = _mods_unloading_order

vmf/scripts/mods/vmf/modules/vmf_package_manager.lua

@@ -0,0 +1,185 @@
+local vmf = get_mod("VMF")
+
+local NOOP = function() end
+
+local _queued_packages = {}
+local _loading_package = nil
+local _loaded_packages = {}
+
+-- #####################################################################################################################
+-- ##### VMFMod ########################################################################################################
+-- #####################################################################################################################
+
+--[[
+  Loads a mod package.
+  * package_name [string]  : package name. needs to be the full path to the `.package` file without the extension
+  * callback     [function]: (optional) callback for asynchronous loading
+  * sync         [boolean] : (optional) load the packages synchronously, freezing the game until it is loaded
+--]]
+function VMFMod:load_package(package_name, callback, sync)
+  if vmf.check_wrong_argument_type(self, "load_package", "package_name", package_name, "string") or
+     vmf.check_wrong_argument_type(self, "load_package", "callback", callback, "function", "nil") or
+     vmf.check_wrong_argument_type(self, "load_package", "sync", sync, "boolean", "nil")
+  then
+    return
+  end
+
+  if self:has_package_loaded(package_name) then
+    self:error("Package '%s' has already been loaded", package_name)
+    return
+  end
+
+  local mod_handle = self:get_internal_data("mod_handle")
+  if not mod_handle then
+    self:error("Failed to get mod handle. Package management is not available.")
+    return
+  end
+
+  if not _loaded_packages[self] then
+    _loaded_packages[self] = {}
+  end
+
+  local resource_package = Mod.resource_package(mod_handle, package_name)
+  if not resource_package then
+    self:error("Could not find package '%s'.", package_name)
+    return
+  end
+
+  local is_loading = self:is_package_loading(package_name)
+
+  if sync then
+    if not is_loading then
+      resource_package:load()
+    end
+
+    resource_package:flush()
+
+    _loaded_packages[self][package_name] = resource_package
+  else
+    if is_loading then
+      self:error("Package '%s' is currently loading", package_name)
+      return
+    end
+
+    table.insert(_queued_packages, {
+      mod = self,
+      package_name = package_name,
+      resource_package = resource_package,
+      callback = callback or NOOP,
+    })
+  end
+end
+
+
+--[[
+  Unlaods a loaded mod package.
+  * package_name [string]: package name. needs to be the full path to the `.package` file without the extension
+--]]
+function VMFMod:unload_package(package_name)
+  if vmf.check_wrong_argument_type(self, "unload_package", "package_name", package_name, "string") then
+    return
+  end
+
+  if not self:has_package_loaded(package_name) then
+    self:error("Package '%s' has not been loaded", package_name)
+    return
+  end
+
+  local resource_package = _loaded_packages[self][package_name]
+
+  resource_package:unload()
+  Mod.release_resource_package(resource_package)
+  _loaded_packages[self][package_name] = nil
+end
+
+
+--[[
+  Returns whether the mod package is currently being loaded.
+  * package_name [string]: package name. needs to be the full path to the `.package` file without the extension
+--]]
+function VMFMod:is_package_loading(package_name)
+  if vmf.check_wrong_argument_type(self, "is_package_loading", "package_name", package_name, "string") then
+    return
+  end
+
+  if _loading_package and _loading_package.mod == self and _loading_package.package_name == package_name then
+    return true
+  end
+
+  for _, queued_package in ipairs(_queued_packages) do
+    if queued_package.mod == self and queued_package.package_name == package_name then
+      return true
+    end
+  end
+
+  return false
+end
+
+
+--[[
+  Returns whether the mod package has been fully loaded.
+  * package_name [string]: package name. needs to be the full path to the `.package` file without the extension
+--]]
+function VMFMod:has_package_loaded(package_name)
+  if vmf.check_wrong_argument_type(self, "has_package_loaded", "package_name", package_name, "string") then
+    return
+  end
+
+  local loaded_packages = _loaded_packages[self]
+  return loaded_packages and loaded_packages[package_name] ~= nil
+end
+
+-- #####################################################################################################################
+-- ##### VMF internal functions and variables ##########################################################################
+-- #####################################################################################################################
+
+-- Loads queued packages one at a time
+function vmf.update_package_manager()
+  local loading_package = _loading_package
+  if loading_package and loading_package.resource_package:has_loaded() then
+    loading_package.resource_package:flush()
+
+    _loaded_packages[loading_package.mod][loading_package.package_name] = loading_package.resource_package
+    _loading_package = nil
+
+    -- The callback has to be called last, so that any calls to `has_package_loaded` or `is_package_loading`
+    -- return the correct value
+    vmf.safe_call_nr(loading_package.mod, {"'%s' package loaded callback", loading_package.package_name},
+                      loading_package.callback, loading_package.package_name)
+  end
+
+  local queued_package = _queued_packages[1]
+  if queued_package and not _loading_package then
+    _loading_package = queued_package
+    table.remove(_queued_packages, 1)
+
+    _loading_package.resource_package:load()
+  end
+end
+
+
+-- Forcefully unloads all mods and cleans the queue.
+function vmf.unload_all_resource_packages()
+  for mod, packages in pairs(_loaded_packages) do
+    for package_name in pairs(packages) do
+      mod:warning(
+        "Force-unloading package '%s'. Please make sure to properly release packages when the mod is unloaded",
+        package_name
+      )
+      mod:unload_package(package_name)
+    end
+  end
+
+  _queued_packages = {}
+
+  if _loading_package then
+    _loading_package.mod:warning(
+      "Still loading package '%s'. Memory leaks may occur when unloading while a package is loading.",
+      _loading_package.package_name
+    )
+
+    _loading_package.callback = function(package_name)
+      _loading_package.mod:unload_package(package_name)
+    end
+  end
+end

vmf/scripts/mods/vmf/vmf_loader.lua

@@ -13,6 +13,7 @@ local vmf_mod_object = {}
 function vmf_mod_object:init()
 	dofile("scripts/mods/vmf/modules/vmf_mod_data")
 	dofile("scripts/mods/vmf/modules/vmf_mod_manager")
+	dofile("scripts/mods/vmf/modules/vmf_package_manager")
 	dofile("scripts/mods/vmf/modules/core/safe_calls")
 	dofile("scripts/mods/vmf/modules/core/events")
 	dofile("scripts/mods/vmf/modules/core/settings")
@@ -55,6 +56,7 @@ end
 -- #####################################################################################################################
 
 function vmf_mod_object:update(dt)
+	vmf.update_package_manager()
 	vmf.mods_update_event(dt)
 	vmf.check_keybinds()
 	vmf.execute_queued_chat_command()
@@ -90,6 +92,7 @@ function vmf_mod_object:on_reload()
 	if VT1 then vmf.reset_map_view() end
 	vmf.mods_unload_event(false)
 	vmf.remove_custom_views()
+	vmf.unload_all_resource_packages()
 	vmf.hooks_unload()
 	vmf.reset_guis()
 end