Darktide-Mod-Loader/scripts/mods/dml/hook.lua

256 lines
6.3 KiB
Lua

-- Hook structure
MODS_HOOKS = MODS_HOOKS or {}
MODS_HOOKS_BY_FILE = MODS_HOOKS_BY_FILE or {}
local function NOOP() end
local item_template = {
name = "",
func = NOOP,
hooks = {},
}
local item_hook_template = {
name = "",
func = NOOP,
enable = false,
exec = NOOP,
}
local Log = Log
local function print_log_info(mod_name, message)
Log = Log or rawget(_G, "Log")
if Log then
Log._info(mod_name, message)
else
print("[" .. mod_name .. "]: " .. message)
end
end
--
-- Get function by function name
--
local function get_func(obj, func_name)
return obj[func_name]
end
--
-- Get item by function name
--
local function get_item(obj, func_name)
-- Find existing item
for _, item in ipairs(MODS_HOOKS) do
if item.obj == obj and item.name == func_name then
return item
end
end
-- Create new item
local item = table.clone(item_template)
item.obj = obj
item.name = func_name
item.func = get_func(obj, func_name)
-- Save
table.insert(MODS_HOOKS, item)
return item
end
--
-- Get item hook by mod name
--
local function get_item_hook(item, mod_name)
-- Find existing item
for _, hook in ipairs(item.hooks) do
if hook.name == mod_name then
return hook
end
end
-- Create new item
local item_hook = table.clone(item_hook_template)
item_hook.name = mod_name
-- Save
table.insert(item.hooks, 1, item_hook)
return item_hook
end
--
-- If settings are changed the hook itself needs to be updated
--
local function patch()
for i, item in ipairs(MODS_HOOKS) do
local last_j = 1
for j, hook in ipairs(item.hooks) do
local is_first_hook = j == 1
if is_first_hook then
if hook.enable then
MODS_HOOKS[i].hooks[j].exec = function(...)
local mod_hook = MODS_HOOKS[i]
return mod_hook.hooks[j].func(mod_hook.func, ...)
end
else
MODS_HOOKS[i].hooks[j].exec = function(...)
return MODS_HOOKS[i].func(...)
end
end
else
if hook.enable then
MODS_HOOKS[i].hooks[j].exec = function(...)
local mod_hook = MODS_HOOKS[i]
return mod_hook.hooks[j].func(mod_hook.hooks[j - 1].exec, ...)
end
else
MODS_HOOKS[i].hooks[j].exec = function(...)
return MODS_HOOKS[i].hooks[j - 1].exec(...)
end
end
end
last_j = j
end
-- Patch orginal function call
item.obj[item.name] = MODS_HOOKS[i].hooks[last_j].exec
end
end
--
-- Set hook
--
local function set(mod_name, obj, func_name, hook_func)
local item = get_item(obj, func_name)
local item_hook = get_item_hook(item, mod_name)
print_log_info(mod_name, "Hooking " .. func_name)
item_hook.enable = true
item_hook.func = hook_func
patch()
end
--
-- Set hook on every instance of the given file
--
local function set_on_file(mod_name, filepath, func_name, hook_func)
-- Add hook create function to list for the file
MODS_HOOKS_BY_FILE[filepath] = MODS_HOOKS_BY_FILE[filepath] or {}
local hook_create_func = function(this_filepath, this_index)
local dynamic_func_name = string.format(
"Mods.require_store[\"%s\"][%i].%s",
this_filepath, this_index, func_name
)
set(mod_name, dynamic_func_name, hook_func, false)
end
table.insert(MODS_HOOKS_BY_FILE[filepath], hook_create_func)
-- Add the new hook to every instance of the file
local all_file_instances = Mods.require_store[filepath]
if all_file_instances then
for i, item in ipairs(all_file_instances) do
if item then
hook_create_func(filepath, i)
end
end
end
end
--
-- Enable/Disable hook
--
local function enable(value, mod_name, func_name)
for _, item in ipairs(MODS_HOOKS) do
if item.name == func_name or func_name == nil then
for _, hook in ipairs(item.hooks) do
if hook.name == mod_name then
hook.enable = value
patch()
end
end
end
end
return
end
--
-- Enable all hooks on a stored file
--
local function enable_by_file(filepath, store_index)
local all_file_instances = Mods.require_store[filepath]
local file_instance = all_file_instances and all_file_instances[store_index]
local all_file_hooks = MODS_HOOKS_BY_FILE[filepath]
if all_file_hooks and file_instance then
for _, hook_create_func in ipairs(all_file_hooks) do
hook_create_func(filepath, store_index)
end
end
end
--
-- Remove hook from chain
--
local function remove(func_name, mod_name)
for i, item in ipairs(MODS_HOOKS) do
if item.name == func_name then
if mod_name ~= nil then
for j, hook in ipairs(item.hooks) do
if hook.name == mod_name then
table.remove(item.hooks, j)
patch()
end
end
else
-- Restore orginal function
item.obj[item.name] = MODS_HOOKS[i].func
-- Remove hook function
table.remove(MODS_HOOKS, i)
return
end
end
end
return
end
--
-- Move hook to front of the hook chain
--
local function front(mod_name, func_name)
for _, item in ipairs(MODS_HOOKS) do
if item.name == func_name or func_name == nil then
for i, hook in ipairs(item.hooks) do
if hook.name == mod_name then
local saved_hook = table.clone(hook)
table.remove(item.hooks, i)
table.insert(item.hooks, saved_hook)
patch()
end
end
end
end
return
end
Mods.hook = {
set = set,
set_on_file = set_on_file,
enable = enable,
enable_by_file = enable_by_file,
remove = remove,
front = front,
_get_item = get_item,
_get_item_hook = get_item_hook,
_patch = patch,
}