/**
   Timer library for OCT
   Lua functions will be able to register a function to be called after a certain amount of time. Timer values are updated on every call to the rendering loop, and when timer hits 0 the corresponding function is called
   Optionally, we can also specify a string argument to be passed to the function when called
 **/
#ifndef OCT_TIMER_H
#define OCT_TIMER_H

#include <inttypes.h>
#include <lua5.3/lualib.h>
#include <lua5.3/lauxlib.h>

#define OCT_TIMER_MAXIMUM_FUNCTION_NAME_LENGTH 128
#define OCT_TIMER_MAXIMUM_ARGUMENT_LENGTH 128
#define OCT_TIMER_MAXIMUM_ID_LENGTH 128
#define OCT_TIMER_INITIAL_NUM_TIMERS 10
#define OCT_TIMER_LIST_REALLOC_LENGTH 10

struct oct_timer_elem {
	char id[OCT_TIMER_MAXIMUM_ID_LENGTH];
	int64_t millis;
	char lua_function[OCT_TIMER_MAXIMUM_FUNCTION_NAME_LENGTH];
	char lua_argument[OCT_TIMER_MAXIMUM_ARGUMENT_LENGTH];
	struct oct_timer_elem* next;
	struct oct_timer_elem* prev;
};

// Timer list is a doubly-linked list with O(1) inserts
// I can't imagine we're cancelling timers that often so this is fine
// Instead I think we will be inserting most of the time
// I could optimize this by inserting new timers in order of time to execution, but I don't see a reason to optimize yet
// O(1) inserts, O(n) accesses
struct oct_timer_list_ {
	uint32_t size;
	struct oct_timer_elem* first;
	struct oct_timer_elem* last;
};

extern struct oct_timer_list_ oct_timer_list;

int oct_timer_list_initialize();
int oct_timer_list_deinitialize();
int oct_timer_initialize_lua(lua_State *L);
int oct_timer_register(lua_State *L);
int oct_timer_unregister_lua(lua_State *L);
int oct_timer_unregister(char* id, int do_free); // free = 0 => depend on user to free the unregistered elem, free = 1 => free the unregistered elem
struct oct_timer_elem* oct_timer_find(char* id);
int oct_timer_tick(lua_State *L);

#endif