#![allow(non_camel_case_types)]
#![allow(non_snake_case)]
#![allow(improper_ctypes)]

use libc::{c_int, c_char, c_void, c_double, size_t, ptrdiff_t};

use std::ptr;

#[macro_export]
macro_rules! c_str {
    ($str:expr) => (concat!($str, '\0').as_ptr() as *const i8)
}

pub const FREELIST_REF: c_int = 0;

pub const LUA_REGISTRYINDEX: c_int = -10000;
pub const LUA_ENVIRONINDEX: c_int = -10001;
pub const LUA_GLOBALSINDEX: c_int = -10002;

pub const LUA_YIELD: c_int =     1;
pub const LUA_ERRRUN: c_int =    2;
pub const LUA_ERRSYNTAX: c_int = 3;
pub const LUA_ERRMEM: c_int =    4;
pub const LUA_ERRERR: c_int =    5;

pub const LUA_MULTRET: c_int = -1;

pub const LUA_TNONE: c_int = -1;
pub const LUA_TNIL: c_int = 0;
pub const LUA_TBOOLEAN: c_int = 1;
pub const LUA_TLIGHTUSERDATA: c_int = 2;
pub const LUA_TNUMBER: c_int = 3;
pub const LUA_TSTRING: c_int = 4;
pub const LUA_TTABLE: c_int = 5;
pub const LUA_TFUNCTION: c_int = 6;
pub const LUA_TUSERDATA: c_int = 7;
pub const LUA_TTHREAD: c_int = 8;

pub type lua_Number = c_double;
pub type lua_Integer = ptrdiff_t;

#[repr(C)]
pub struct lua_State;

#[repr(C)]
pub struct ZIO;

#[repr(C)]
pub struct lua_Debug {
    event: c_int,
    name: *const c_char,
    namewhat: *const c_char,
    what: *const c_char,
    source: *const c_char,
    currentline: c_int,
    nups: c_int,
    linedefined: c_int,
    lastlinedefined: c_int,
    short_src: [c_char; 60],
    i_ci: c_int,
}

pub type lua_CFunction = unsafe extern "C" fn(L: *mut lua_State) -> c_int;

pub type lua_Reader = unsafe extern "C" fn(L: *mut lua_State, ud: *mut c_void, sz: *mut size_t) -> *const c_char;
pub type lua_Chunkreader = lua_Reader;

pub type lua_Writer = unsafe extern "C" fn(L: *mut lua_State, p: *const c_void, sz: size_t, ud: *mut c_void) -> c_int;
pub type lua_Chunkwriter = lua_Writer;

pub type lua_Alloc = unsafe extern "C" fn(ud: *mut c_void, ptr: *mut c_void, osize: size_t, nsize: size_t) -> *mut c_void;
pub type lua_Hook = unsafe extern "C" fn(L: *mut lua_State, ar: *mut lua_Debug);

extern "C" {
    // state manipulation
    pub fn lua_newstate(f: lua_Alloc, ud: *mut c_void) -> *mut lua_State;
    pub fn lua_close(L: *mut lua_State);
    pub fn lua_newthread(L: *mut lua_State) -> *mut lua_State;

    pub fn lua_atpanic(L: *mut lua_State, panicf: lua_CFunction) -> lua_CFunction;

    // basic stack manipulation
    pub fn lua_gettop(L: *mut lua_State) -> c_int;
    pub fn lua_settop(L: *mut lua_State, idx: c_int);
    pub fn lua_pushvalue(L: *mut lua_State, idx: c_int);
    pub fn lua_remove(L: *mut lua_State, idx: c_int);
    pub fn lua_insert(L: *mut lua_State, idx: c_int);
    pub fn lua_replace(L: *mut lua_State, idx: c_int);
    pub fn lua_checkstack(L: *mut lua_State, sz: c_int) -> c_int;

    pub fn lua_xmove(from: *mut lua_State, to: *mut lua_State, n: c_int);

    // access functions (stack -> C)
    pub fn lua_isnumber(L: *mut lua_State, idx: c_int) -> c_int;
    pub fn lua_isstring(L: *mut lua_State, idx: c_int) -> c_int;
    pub fn lua_iscfunction(L: *mut lua_State, idx: c_int) -> c_int;
    pub fn lua_isuserdata(L: *mut lua_State, idx: c_int) -> c_int;
    pub fn lua_type(L: *mut lua_State, idx: c_int) -> c_int;
    pub fn lua_typename(L: *mut lua_State, tp: c_int) -> *const c_char;

    pub fn lua_equal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
    pub fn lua_rawequal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
    pub fn lua_lessthan(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;

    pub fn lua_tonumber(L: *mut lua_State, idx: c_int) -> lua_Number;
    pub fn lua_tointeger(L: *mut lua_State, idx: c_int) -> lua_Integer;
    pub fn lua_toboolean(L: *mut lua_State, idx: c_int) -> c_int;
    pub fn lua_tolstring(L: *mut lua_State, idx: c_int, len: *mut size_t) -> *const c_char;
    pub fn lua_objlen(L: *mut lua_State, idx: c_int) -> size_t;
    pub fn lua_tocfunction(L: *mut lua_State, idx: c_int) -> Option<lua_CFunction>;
    pub fn lua_touserdata(L: *mut lua_State, idx: c_int) -> *mut c_void;
    pub fn lua_tothread(L: *mut lua_State, idx: c_int) -> *mut lua_State;
    pub fn lua_topointer(L: *mut lua_State, idx: c_int) -> *const c_void;

    // push functions (C -> stack)
    pub fn lua_pushnil(L: *mut lua_State);
    pub fn lua_pushnumber(L: *mut lua_State, n: lua_Number);
    pub fn lua_pushinteger(L: *mut lua_State, n: lua_Integer);
    pub fn lua_pushlstring(L: *mut lua_State, s: *const c_char, l: size_t);
    pub fn lua_pushstring(L: *mut lua_State, s: *const c_char);
    pub fn lua_pushfstring(L: *mut lua_State, fmt: *const c_char, ...) -> *const c_char;
    pub fn lua_pushcclosure(L: *mut lua_State, f: lua_CFunction, n: c_int);
    pub fn lua_pushboolean(L: *mut lua_State, b: c_int);
    pub fn lua_pushlightuserdata(L: *mut lua_State, p: *mut c_void);
    pub fn lua_pushthread(L: *mut lua_State) -> c_int;

    // get functions (Lua -> stack)
    pub fn lua_gettable(L: *mut lua_State, idx: c_int);
    pub fn lua_getfield(L: *mut lua_State, idx: c_int, k: *const c_char);
    pub fn lua_rawget(L: *mut lua_State, idx: c_int);
    pub fn lua_rawgeti(L: *mut lua_State, idx: c_int, n: c_int);
    pub fn lua_createtable(L: *mut lua_State, narr: c_int, nrec: c_int);
    pub fn lua_newuserdata(L: *mut lua_State, sz: size_t) -> *mut c_void;
    pub fn lua_getmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
    pub fn lua_getfenv(L: *mut lua_State, idx: c_int);

    // set functions (stack -> Lua)
    pub fn lua_settable(L: *mut lua_State, idx: c_int);
    pub fn lua_setfield(L: *mut lua_State, idx: c_int, k: *const c_char);
    pub fn lua_rawset(L: *mut lua_State, idx: c_int);
    pub fn lua_rawseti(L: *mut lua_State, idx: c_int, n: c_int);
    pub fn lua_setmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
    pub fn lua_setfenv(L: *mut lua_State, idx: c_int) -> c_int;

    // `load' and `call' functions (load and run Lua code)
    pub fn lua_call(L: *mut lua_State, nargs: c_int, nresults: c_int);
    pub fn lua_pcall(L: *mut lua_State, nargs: c_int, nresults: c_int, errfunc: c_int) -> c_int;
    pub fn lua_cpcall(L: *mut lua_State, func: lua_CFunction, ud: *mut c_void) -> c_int;
    pub fn lua_load(L: *mut lua_State, reader: lua_Reader, dt: *mut c_void, chunkname: *const c_char) -> c_int;
    pub fn lua_dump(L: *mut lua_State, writer: lua_Writer, data: *mut c_void) -> c_int;

    // coroutine functions
    pub fn lua_yield(L: *mut lua_State, nresults: c_int) -> c_int;
    pub fn lua_resume(L: *mut lua_State, narg: c_int) -> c_int;
    pub fn lua_status(L: *mut lua_State) -> c_int;

    // garbage-collection function
    pub fn lua_gc(L: *mut lua_State, what: c_int, data: c_int) -> c_int;

    // miscellaneous functions
    pub fn lua_error(L: *mut lua_State) -> c_int;
    pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
    pub fn lua_concat(L: *mut lua_State, n: c_int);

    pub fn lua_getallocf(L: *mut lua_State, ud: *mut *mut c_void) -> lua_Alloc;
    pub fn lua_setallocf(L: *mut lua_State, f: lua_Alloc, ud: *mut c_void);


    pub fn lua_getstack(L: *mut lua_State, level: c_int, ar: *mut lua_Debug) -> c_int;
    pub fn lua_getinfo(L: *mut lua_State, what: *const c_char, ar: *mut lua_Debug) -> c_int;
    pub fn lua_getlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
    pub fn lua_setlocal(L: *mut lua_State, ar: *mut lua_Debug, n: c_int) -> *const c_char;
    pub fn lua_getupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
    pub fn lua_setupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;

    pub fn lua_upvalueid(L: *mut lua_State, fidx: c_int, n: c_int) -> *const c_void;
    pub fn lua_upvaluejoin(L: *mut lua_State, fidx1: c_int, n1: c_int, fidx2: c_int, n2: c_int);

    pub fn lua_sethook(L: *mut lua_State, func: lua_Hook, mask: c_int, count: c_int) -> c_int;
    pub fn lua_gethook(L: *mut lua_State) -> lua_Hook;
    pub fn lua_gethookmask(L: *mut lua_State) -> c_int;
    pub fn lua_gethookcount(L: *mut lua_State) -> c_int;

    pub fn luaL_newstate() -> *mut lua_State;

    pub fn luaopen_base(L: *mut lua_State) -> c_int;
    pub fn luaopen_table(L: *mut lua_State) -> c_int;
    pub fn luaopen_io(L: *mut lua_State) -> c_int;
    pub fn luaopen_os(L: *mut lua_State) -> c_int;
    pub fn luaopen_string(L: *mut lua_State) -> c_int;
    pub fn luaopen_math(L: *mut lua_State) -> c_int;
    pub fn luaopen_debug(L: *mut lua_State) -> c_int;
    pub fn luaopen_package(L: *mut lua_State) -> c_int;
    pub fn luaL_openlibs(L: *mut lua_State);

    pub fn luaL_loadstring(L: *mut lua_State, s: *const c_char) -> c_int;

    pub fn luaL_ref(L: *mut lua_State, t: c_int) -> c_int;
    pub fn luaL_unref(L: *mut lua_State, t: c_int, tref: c_int);
}

#[inline(always)]
pub unsafe fn lua_upvalueindex(idx: c_int) -> c_int {
    LUA_GLOBALSINDEX - idx
}

#[inline(always)]
pub unsafe fn lua_pop(L: *mut lua_State, n: c_int) {
    lua_settop(L, -n - 1)
}

#[inline(always)]
pub unsafe fn lua_newtable(L: *mut lua_State) {
    lua_createtable(L, 0, 0)
}

#[inline(always)]
pub unsafe fn lua_register(L: *mut lua_State, name: *const c_char, f: lua_CFunction) {
    lua_pushcfunction(L, f);
    lua_setglobal(L, name)
}

#[inline(always)]
pub unsafe fn lua_pushcfunction(L: *mut lua_State, f: lua_CFunction) {
    lua_pushcclosure(L, f, 0)
}

#[inline(always)]
pub unsafe fn lua_strlen(L: *mut lua_State, idx: c_int) -> size_t {
    lua_objlen(L, idx)
}

#[inline(always)]
pub unsafe fn lua_isfunction(L: *mut lua_State, idx: c_int) -> bool {
    lua_type(L, idx) == LUA_TFUNCTION
}

#[inline(always)]
pub unsafe fn lua_istable(L: *mut lua_State, idx: c_int) -> bool {
    lua_type(L, idx) == LUA_TTABLE
}

#[inline(always)]
pub unsafe fn lua_islightuserdata(L: *mut lua_State, idx: c_int) -> bool {
    lua_type(L, idx) == LUA_TLIGHTUSERDATA
}

#[inline(always)]
pub unsafe fn lua_isnil(L: *mut lua_State, idx: c_int) -> bool {
    lua_type(L, idx) == LUA_TNIL
}

#[inline(always)]
pub unsafe fn lua_isboolean(L: *mut lua_State, idx: c_int) -> bool {
    lua_type(L, idx) == LUA_TBOOLEAN
}

#[inline(always)]
pub unsafe fn lua_isthread(L: *mut lua_State, idx: c_int) -> bool {
    lua_type(L, idx) == LUA_TTHREAD
}

#[inline(always)]
pub unsafe fn lua_isnone(L: *mut lua_State, idx: c_int) -> bool {
    lua_type(L, idx) == LUA_TNONE
}

#[inline(always)]
pub unsafe fn lua_isnoneornil(L: *mut lua_State, idx: c_int) -> bool {
    lua_type(L, idx) <= 0
}

#[inline(always)]
pub unsafe fn lua_pushliteral(L: *mut lua_State, s: &'static str) {
    lua_pushlstring(L, s.as_ptr() as *const c_char, s.len());
}

#[inline(always)]
pub unsafe fn lua_setglobal(L: *mut lua_State, s: *const c_char) {
    lua_setfield(L, LUA_GLOBALSINDEX, s);
}

#[inline(always)]
pub unsafe fn lua_getglobal(L: *mut lua_State, s: *const c_char) {
    lua_getfield(L, LUA_GLOBALSINDEX, s);
}

#[inline(always)]
pub unsafe fn lua_tostring(L: *mut lua_State, i: c_int) -> *const c_char {
    lua_tolstring(L, i, ptr::null_mut())
}

#[inline(always)]
pub unsafe fn luaL_dostring(L: *mut lua_State, s: *const c_char) -> c_int {
    luaL_loadstring(L, s) & lua_pcall(L, 0, LUA_MULTRET, 0)
}