Files
mod-ale/HookHelpers.h
2015-01-20 17:17:02 +02:00

130 lines
4.4 KiB
C++

/*
* Copyright (C) 2010 - 2015 Eluna Lua Engine <http://emudevs.com/>
* This program is free software licensed under GPL version 3
* Please see the included DOCS/LICENSE.md for more information
*/
#ifndef _HOOK_HELPERS_H
#define _HOOK_HELPERS_H
#include "LuaEngine.h"
#include "ElunaUtility.h"
/*
* Sets up the stack so that event handlers can be called.
*
* Returns the number of functions that were pushed onto the stack.
*
* Use the simpler overloads for just EventBind or EntryBind instead of this overload in hooks.
*/
template<typename T>
int Eluna::SetupStack(EventBind<T>* event_bindings, EntryBind<T>* entry_bindings, UniqueBind<T>* guid_bindings, T event_id, uint32 entry, uint64 guid, uint32 instanceId, int number_of_arguments)
{
// Ensure that if `entry_bindings` is not NULL, a valid entry is supplied.
ASSERT(!entry_bindings || (entry_bindings && entry > 0));
ASSERT(number_of_arguments == this->push_counter);
// Stack: [arguments]
Push(event_id);
this->push_counter = 0;
++number_of_arguments;
// Stack: [arguments], event_id
int arguments_top = lua_gettop(L);
int first_argument_index = arguments_top - number_of_arguments + 1;
ASSERT(arguments_top >= number_of_arguments);
lua_insert(L, first_argument_index);
// Stack: event_id, [arguments]
if (event_bindings)
event_bindings->PushFuncRefs(L, (int)event_id);
if (entry_bindings)
entry_bindings->PushFuncRefs(L, (int)event_id, entry);
if (guid_bindings)
guid_bindings->PushFuncRefs(L, (int)event_id, guid, instanceId);
// Stack: event_id, [arguments], [functions]
int number_of_functions = lua_gettop(L) - arguments_top;
return number_of_functions;
}
/*
* Replace one of the arguments pushed before `SetupStack` with a new value.
*/
template<typename T>
void Eluna::ReplaceArgument(T value, uint8 index)
{
ASSERT(index < lua_gettop(L) && index > 0);
// Stack: event_id, [arguments], [functions], [results]
Eluna::Push(L, value);
// Stack: event_id, [arguments], [functions], [results], value
lua_replace(L, index + 1);
// Stack: event_id, [arguments and value], [functions], [results]
}
/*
* Call all event handlers registered to the event ID/entry combination and ignore any results.
*/
template<typename T>
void Eluna::CallAllFunctions(EventBind<T>* event_bindings, EntryBind<T>* entry_bindings, UniqueBind<T>* guid_bindings, T event_id, uint32 entry, uint64 guid, uint32 instanceId)
{
int number_of_arguments = this->push_counter;
// Stack: [arguments]
int number_of_functions = SetupStack(event_bindings, entry_bindings, guid_bindings, event_id, entry, guid, instanceId, number_of_arguments);
// Stack: event_id, [arguments], [functions]
while (number_of_functions > 0)
{
CallOneFunction(number_of_functions, number_of_arguments, 0);
--number_of_functions;
// Stack: event_id, [arguments], [functions - 1]
}
// Stack: event_id, [arguments]
CleanUpStack(number_of_arguments);
// Stack: (empty)
}
/*
* Call all event handlers registered to the event ID/entry combination,
* and returns `default_value` if ALL event handlers returned `default_value`,
* otherwise returns the opposite of `default_value`.
*/
template<typename T>
bool Eluna::CallAllFunctionsBool(EventBind<T>* event_bindings, EntryBind<T>* entry_bindings, UniqueBind<T>* guid_bindings, T event_id, uint32 entry, uint64 guid, uint32 instanceId, bool default_value)
{
bool result = default_value;
// Note: number_of_arguments here does not count in eventID, which is pushed in SetupStack
int number_of_arguments = this->push_counter;
// Stack: [arguments]
int number_of_functions = SetupStack(event_bindings, entry_bindings, guid_bindings, event_id, entry, guid, instanceId, number_of_arguments);
// Stack: event_id, [arguments], [functions]
while (number_of_functions > 0)
{
int r = CallOneFunction(number_of_functions, number_of_arguments, 1);
--number_of_functions;
// Stack: event_id, [arguments], [functions - 1], result
if (lua_isboolean(L, r) && (lua_toboolean(L, r) == 1) != default_value)
result = !default_value;
lua_pop(L, 1);
// Stack: event_id, [arguments], [functions - 1]
}
// Stack: event_id, [arguments]
CleanUpStack(number_of_arguments);
// Stack: (empty)
return result;
}
#endif // _HOOK_HELPERS_H