-- INTERNAL
-- definitions of BUILD and game types for the Lunatic Interpreter

local ffi = require("ffi")

---- sector, wall, sprite, ... ----
ffi.cdef[[
#pragma pack(push,1)
typedef struct
{
    const int16_t wallptr, wallnum;
    int32_t ceilingz, floorz;
    int16_t ceilingstat, floorstat;
    int16_t ceilingpicnum, ceilingheinum;
    int8_t ceilingshade;
    uint8_t ceilingpal, ceilingxpanning, ceilingypanning;
    int16_t floorpicnum, floorheinum;
    int8_t floorshade;
    uint8_t floorpal, floorxpanning, floorypanning;
    uint8_t visibility, filler;
    int16_t lotag, hitag, extra;
} sectortype;

typedef struct
{
    int32_t x, y;
    const int16_t point2, nextwall, nextsector;
    int16_t cstat;
    int16_t picnum, overpicnum;
    int8_t shade;
    uint8_t pal, xrepeat, yrepeat, xpanning, ypanning;
    int16_t lotag, hitag, extra;
} walltype;

typedef struct
{
    int32_t x, y, z;
    int16_t cstat, picnum;
    int8_t shade;
    uint8_t pal, clipdist, filler;
    uint8_t xrepeat, yrepeat;
    int8_t xoffset, yoffset;
    const int16_t sectnum, statnum;
    int16_t ang, owner, xvel, yvel, zvel;
    int16_t lotag, hitag, extra;
} spritetype;

typedef struct {
    const uint32_t mdanimtims;
    const int16_t mdanimcur;
    int16_t angoff, pitch, roll;
    int32_t xoff, yoff, zoff;
    uint8_t flags;
    uint8_t xpanning, ypanning;
    const uint8_t filler;
    float alpha;
    const int32_t _do_not_use1;
    const int32_t _do_not_use2;
} spriteext_t;

typedef struct {
    int32_t x, y, z;
} vec3_t;
#pragma pack(pop)

enum
{
    MAXSECTORS = 4096,
    MAXWALLS = 16384,
    MAXSPRITES = 16384,

    MAXSTATUS = 1024,

    MAXBUNCHES = 256,
    CEILING = 0,
    FLOOR = 1,
};
]]

assert(ffi.sizeof('sectortype')==40)
assert(ffi.sizeof('walltype')==32)
assert(ffi.sizeof('spritetype')==44)

---- engine data and functions ----

ffi.cdef[[int32_t engine_main_arrays_are_static;]]

-- NOTE TO SELF: This is not C, never EVER write
--    if (x)
-- when checking a C variable x for 'thuthiness'
if (ffi.C.engine_main_arrays_are_static ~= 0) then
--    print('main arrays are static');
    ffi.cdef[[
sectortype sector[];
walltype wall[];
spritetype sprite[];
spriteext_t spriteext[];
]]
else
--    print('main arrays are pointers');
    ffi.cdef[[
sectortype *sector;
walltype *wall;
spritetype *sprite;
spriteext_t *spriteext;
]]
end

ffi.cdef[[
const int16_t numsectors, numwalls;
const int32_t numyaxbunches;

const int16_t headspritesect[MAXSECTORS+1], headspritestat[MAXSTATUS+1];
const int16_t prevspritesect[MAXSPRITES], prevspritestat[MAXSPRITES];
const int16_t nextspritesect[MAXSPRITES], nextspritestat[MAXSPRITES];

const int16_t headsectbunch[2][MAXBUNCHES], nextsectbunch[2][MAXSECTORS];


int16_t yax_getbunch(int16_t i, int16_t cf);
]]


---- game structs ----
ffi.cdef[[
#pragma pack(push,1)
// ACTOR_T, might still need to make some fields read-only
typedef struct
{
    const int32_t t_data[10];  // 40b sometimes used to hold offsets to con code
    int16_t picnum,ang,extra,owner; //8b
    int16_t movflag,tempang,timetosleep; //6b

    int32_t flags, bposx,bposy,bposz; //16b
    int32_t floorz,ceilingz,lastvx,lastvy; //16b
    int32_t lasttransport; //4b

    const int16_t lightId, lightcount, lightmaxrange, cgg; //8b
    int16_t actorstayput, dispicnum, shootzvel; // 6b

    const int8_t _do_not_use[24];
} actor_t;
#pragma pack(pop)

enum
{
    MAXMOUSEBUTTONS = 10,
    MAXMOUSEAXES = 2,
    MAXJOYBUTTONS = (32+4),
    MAXJOYAXES = 8,
    NUMGAMEFUNCTIONS = 56,
};

typedef struct {
    vec3_t camera;
    int32_t const_visibility,uw_framerate;
    int32_t camera_time,folfvel,folavel,folx,foly,fola;
    int32_t reccnt,crosshairscale;

    int32_t runkey_mode,statusbarscale,mouseaiming,weaponswitch,drawweapon;   // JBF 20031125
    int32_t democams,color,msgdisptime,statusbarmode;
    int32_t m_noexits,noexits,autovote,automsg,idplayers;
    int32_t team, viewbob, weaponsway, althud, weaponscale, textscale;

    int32_t entered_name,screen_tilting,shadows,fta_on,executions,auto_run;
    int32_t coords,tickrate,levelstats,m_coop,coop,screen_size,lockout,crosshair;
    int32_t playerai,angleinterpolation,obituaries;

    int32_t respawn_monsters,respawn_items,respawn_inventory,recstat,monsters_off,brightness;
    int32_t m_respawn_items,m_respawn_monsters,m_respawn_inventory,m_recstat,m_monsters_off,detail;
    int32_t m_ffire,ffire,m_player_skill,m_level_number,m_volume_number,multimode;
    int32_t player_skill,level_number,volume_number,m_marker,marker,mouseflip;

    int32_t configversion;

    int16_t cameraang, camerasect, camerahoriz;
    int16_t pause_on,from_bonus;
    int16_t camerasprite,last_camsprite;
    int16_t last_level,secretlevel, bgstretch;

    struct {
        int32_t UseJoystick;
        int32_t UseMouse;
        int32_t AutoAim;
        int32_t ShowOpponentWeapons;
        int32_t MouseDeadZone,MouseBias;
        int32_t SmoothInput;

        // JBF 20031211: Store the input settings because
        // (currently) jmact can't regurgitate them
        int32_t MouseFunctions[MAXMOUSEBUTTONS][2];
        int32_t MouseDigitalFunctions[MAXMOUSEAXES][2];
        int32_t MouseAnalogueAxes[MAXMOUSEAXES];
        int32_t MouseAnalogueScale[MAXMOUSEAXES];
        int32_t JoystickFunctions[MAXJOYBUTTONS][2];
        int32_t JoystickDigitalFunctions[MAXJOYAXES][2];
        int32_t JoystickAnalogueAxes[MAXJOYAXES];
        int32_t JoystickAnalogueScale[MAXJOYAXES];
        int32_t JoystickAnalogueDead[MAXJOYAXES];
        int32_t JoystickAnalogueSaturate[MAXJOYAXES];
        uint8_t KeyboardKeys[NUMGAMEFUNCTIONS][2];

        //
        // Sound variables
        //
        int32_t FXDevice;
        int32_t MusicDevice;
        int32_t FXVolume;
        int32_t MusicVolume;
        int32_t SoundToggle;
        int32_t MusicToggle;
        int32_t VoiceToggle;
        int32_t AmbienceToggle;

        int32_t NumVoices;
        int32_t NumChannels;
        int32_t NumBits;
        int32_t MixRate;

        int32_t ReverseStereo;

        //
        // Screen variables
        //

        int32_t ScreenMode;

        int32_t ScreenWidth;
        int32_t ScreenHeight;
        int32_t ScreenBPP;

        int32_t ForceSetup;
        int32_t NoAutoLoad;

        int32_t scripthandle;
        int32_t setupread;

        int32_t CheckForUpdates;
        int32_t LastUpdateCheck;
        int32_t useprecache;
    } config;

    char overhead_on,last_overhead,showweapons;
    char god,warp_on,cashman,eog,showallmap;
    char show_help,scrollmode,noclip;
    char ridecule[10][40];
    char savegame[10][22];
    char pwlockout[128],rtsname[128];
    char display_bonus_screen;
    char show_level_text;
} user_defs;

// KEEPINSYNC2
enum GameEvent_t {
    EVENT_INIT,
    EVENT_ENTERLEVEL,
    EVENT_RESETWEAPONS,
    EVENT_RESETINVENTORY,
    EVENT_HOLSTER,
    EVENT_LOOKLEFT,
    EVENT_LOOKRIGHT,
    EVENT_SOARUP,
    EVENT_SOARDOWN,
    EVENT_CROUCH,
    EVENT_JUMP,
    EVENT_RETURNTOCENTER,
    EVENT_LOOKUP,
    EVENT_LOOKDOWN,
    EVENT_AIMUP,
    EVENT_FIRE,
    EVENT_CHANGEWEAPON,
    EVENT_GETSHOTRANGE,
    EVENT_GETAUTOAIMANGLE,
    EVENT_GETLOADTILE,
    EVENT_CHEATGETSTEROIDS,
    EVENT_CHEATGETHEAT,
    EVENT_CHEATGETBOOT,
    EVENT_CHEATGETSHIELD,
    EVENT_CHEATGETSCUBA,
    EVENT_CHEATGETHOLODUKE,
    EVENT_CHEATGETJETPACK,
    EVENT_CHEATGETFIRSTAID,
    EVENT_QUICKKICK,
    EVENT_INVENTORY,
    EVENT_USENIGHTVISION,
    EVENT_USESTEROIDS,
    EVENT_INVENTORYLEFT,
    EVENT_INVENTORYRIGHT,
    EVENT_HOLODUKEON,
    EVENT_HOLODUKEOFF,
    EVENT_USEMEDKIT,
    EVENT_USEJETPACK,
    EVENT_TURNAROUND,
    EVENT_DISPLAYWEAPON,
    EVENT_FIREWEAPON,
    EVENT_SELECTWEAPON,
    EVENT_MOVEFORWARD,
    EVENT_MOVEBACKWARD,
    EVENT_TURNLEFT,
    EVENT_TURNRIGHT,
    EVENT_STRAFELEFT,
    EVENT_STRAFERIGHT,
    EVENT_WEAPKEY1,
    EVENT_WEAPKEY2,
    EVENT_WEAPKEY3,
    EVENT_WEAPKEY4,
    EVENT_WEAPKEY5,
    EVENT_WEAPKEY6,
    EVENT_WEAPKEY7,
    EVENT_WEAPKEY8,
    EVENT_WEAPKEY9,
    EVENT_WEAPKEY10,
    EVENT_DRAWWEAPON,
    EVENT_DISPLAYCROSSHAIR,
    EVENT_DISPLAYREST,
    EVENT_DISPLAYSBAR,
    EVENT_RESETPLAYER,
    EVENT_INCURDAMAGE,
    EVENT_AIMDOWN,
    EVENT_GAME,
    EVENT_PREVIOUSWEAPON,
    EVENT_NEXTWEAPON,
    EVENT_SWIMUP,
    EVENT_SWIMDOWN,
    EVENT_GETMENUTILE,
    EVENT_SPAWN,
    EVENT_LOGO,
    EVENT_EGS,
    EVENT_DOFIRE,
    EVENT_PRESSEDFIRE,
    EVENT_USE,
    EVENT_PROCESSINPUT,
    EVENT_FAKEDOMOVETHINGS,
    EVENT_DISPLAYROOMS,
    EVENT_KILLIT,
    EVENT_LOADACTOR,
    EVENT_DISPLAYBONUSSCREEN,
    EVENT_DISPLAYMENU,
    EVENT_DISPLAYMENUREST,
    EVENT_DISPLAYLOADINGSCREEN,
    EVENT_ANIMATESPRITES,
    EVENT_NEWGAME,
    MAXEVENTS
};
]]

ffi.cdef[[
actor_t actor[MAXSPRITES];
user_defs ud;
]]

---- _G tweaks -- pull in only 'safe' stuff ----

local G_ = {}  -- our soon-to-be global environment
local oG = _G

G_.coroutine = coroutine
G_.assert = assert
G_.tostring = tostring
G_.tonumber = tonumber
--rawget
G_.xpcall = xpcall
G_.ipairs = ipairs
G_.print = print
G_.pcall = pcall
--gcinfo --DEPRECATED
--module
--setfenv
--require
--rawset
--jit
G_.bit = bit
--package
G_.error = error
--debug
--loadfile
--rawequal
--load
G_.unpack = unpack
G_.pairs = pairs
G_.table = table
G_._VERSION = _VERSION
--newproxy --NOT STD?
--collectgarbage
--dofile
G_.next = next
G_.math = math
--loadstring
--_G
G_.select = select
G_.string = string
G_.type = type
--getmetatable
--getfenv
--setmetatable

G_._G = G_

-- REMOVE this for release
DBG_ = {}
DBG_.loadstring = oG.loadstring

---- Set up restricted access to ffi.C from lunatic. ----
local ffiC = ffi.C

-- error(..., 2) is to blame the caller and get its line numbers

local det = {}  -- dummy empty table
local tmpmt = {
    __index = function() error('dummy variable: read access forbidden', 2) end,
    __newindex = function() error('dummy variable: write access forbidden', 2) end,
    __metatable = true  -- forbid setting the metatable
}
oG.setmetatable(det, tmpmt)

-- GLOBAL gv: provides access to C global *scalars*
gv = {
    -- all non-scalars need to be explicitly listed
    -- and access to them is redirected to the dummy
    -- empty table... this is somewhat ugly
    sector = det,
    wall = det,
    sprite = det,
    spriteext = det,

    headspritesect = det, headspritestat = det,
    prevspritesect = det, prevspritestat = det,
    nextspritesect = det, nextspritestat = det,

    actor = det,
    ud = det,
}
local tmpmt = {
    __index = ffiC,
    __newindex = function() error("cannot create new or write into existing fields of 'gv'", 2) end,
    __metatable = true,
}
oG.setmetatable(gv, tmpmt)

---- indirect C array access ----
sector = {}
local tmpmt = {
    __index = function(tab, key)
                  if (key >= 0 and key < ffiC.numsectors) then return ffiC.sector[key] end
                  error('out-of-bounds sector[] read access', 2)
              end,

    __newindex = function(tab, key, val) error('cannot write directly to sector[] struct', 2) end,
    __metatable = true,
}
oG.setmetatable(sector, tmpmt)

wall = {}
local tmpmt = {
    __index = function(tab, key)
                  if (key >= 0 and key < ffiC.numwalls) then return ffiC.wall[key] end
                  error('out-of-bounds wall[] read access', 2)
              end,

    __newindex = function(tab, key, val) error('cannot write directly to wall[] struct', 2) end,
    __metatable = true,
}
oG.setmetatable(wall, tmpmt)

-- create a safe indirection for a ffi.C array
local function creategtab(ctab, maxidx, name)
    local tab = {}
    local tmpmt = {
        __index = function(tab, key)
                      if (key>=0 and key < maxidx) then
                          return ctab[key]
                      end
                      error('out-of-bounds '..name..' read access', 2)
                  end,
        __newindex = function(tab, key, val)
                         error('cannot write directly to '..name, 2)
                     end,
        __metatable = true,
    }
    oG.setmetatable(tab, tmpmt)
    return tab
end

sprite = creategtab(ffiC.sprite, ffiC.MAXSPRITES, 'sprite[] struct')
spriteext = creategtab(ffiC.spriteext, ffiC.MAXSPRITES, 'spriteext[] struct')
headspritesect = creategtab(ffiC.headspritesect, ffiC.MAXSECTORS, 'headspritesect[]')
headspritestat = creategtab(ffiC.headspritestat, ffiC.MAXSTATUS, 'headspritestat[]')
nextspritesect = creategtab(ffiC.nextspritesect, ffiC.MAXSPRITES, 'nextspritesect[]')
nextspritestat = creategtab(ffiC.nextspritestat, ffiC.MAXSPRITES, 'nextspritestat[]')
prevspritesect = creategtab(ffiC.prevspritesect, ffiC.MAXSPRITES, 'prevspritesect[]')
prevspritestat = creategtab(ffiC.prevspritestat, ffiC.MAXSPRITES, 'prevspritestat[]')

actor = creategtab(ffiC.actor, ffiC.MAXSPRITES, 'actor[]')

function TEMP_getvollev()  -- REMOVE
    return ffiC.ud.volume_number+1, ffiC.ud.level_number+1
end

---- per-sector/per-statnum sprite iterators ----
local function iter_spritesofsect(sect, i)
    if (i < 0) then
        i = ffiC.headspritesect[sect]
    else
        i = ffiC.nextspritesect[i]
    end

    if (i >= 0) then return i end
end

function spritesofsect(sect)
    if (sect < 0 or sect >= ffiC.numsectors) then
        error("passed invalid sectnum to spritesofsect iterator", 2)
    end

    return iter_spritesofsect, sect, -1
end

local function iter_spritesofstat(stat, i)
    if (i < 0) then
        i = ffiC.headspritestat[stat]
    else
        i = ffiC.nextspritestat[i]
    end

    if (i >= 0) then return i end
end

function spritesofstat(stat)
    if (stat < 0 or stat >= ffiC.MAXSTATUS) then
        error("passed invalid statnum to spritesofstat iterator", 2)
    end

    return iter_spritesofstat, stat, -1
end

-- TROR iterators
local function iter_sectorsofbunch(cf, i)
    if (i < 0) then
        i = ffiC.headsectbunch[cf][-i-1];
    else
        i = ffiC.nextsectbunch[cf][i];
    end

    if (i >= 0) then return i end
end

function sectorsofbunch(bunchnum, cf)
    if (bunchnum < 0 or bunchnum >= ffiC.numyaxbunches) then
        error("passed invalid bunchnum to sectorsofbunch iterator", 2)
    end
    if (cf ~= 0 and cf ~= 1) then
        error("passed invalid 'cf' to sectorsofbunch iterator, must be 0 or 1", 2)
    end

    return iter_sectorsofbunch, cf, -bunchnum-1
end

function getbunch(sectnum, cf)
    if (sectnum < 0 or sectnum >= ffiC.numsectors) then
        error('out-of-bounds sector[] read access', 2)
    end
    if (cf ~= 0 and cf ~= 1) then
        error("passed invalid 'cf' to getbunch, must be 0 or 1", 2)
    end

    return yax_getbunch(sectnum, cf)
end


-- gamevarNames[name] is true if that gamevar was declared
local gamevarNames = {}

-- code for prohibiting initial assignments to create new variables,
-- based on 14.2 of PiL
function gamevar(name, initval)  -- aka 'declare'
    if (type(name) ~= "string") then
        error("First argument to 'gamevar' must be a string", 2);
    end

    if (not string.match(name, "^[%a_][%w_]*$")) then
        error("First argument to 'gamevar' must be a valid identifier", 2);
    end

    if (gamevarNames[name]) then
        error(string.format("Duplicate declaration of identifier '%s'", name), 2)
    end

    if (rawget(G_, name) ~= nil) then
        error(string.format("Identifier name '%s' is already used in the global environment", name), 2)
    end

    gamevarNames[name] = true
    rawset(G_, name, initval or false)
end


---=== Serialization, from PiL with modifications ===---
local function basicSerialize(o)
    if (type(o) == "number") then
        if (o ~= o) then return "0/0" end  -- nan
        if (o == 1/0) then return "1/0" end  -- inf
        if (o == -1/0) then return "-1/0" end  -- -inf

        return tostring(o)
    else  -- must be a string
        if (type(o) ~= "string") then
            error("cannot save a " .. type(o) .. " as key of a table", 3);
        end

        return string.format("%q", o)
    end
end

-- will contain all gamevar tables as keys (and true as value)
local tmpgvtabs = {}

local function save(name, value, saved, strings)
    saved = saved or {}       -- initial value

    strings[#strings+1] = name .. "="

    if (type(value) == "number" or type(value) == "string") then
        strings[#strings+1] = basicSerialize(value) .. "\n"
    elseif (type(value) == "table") then
        if (saved[value]) then    -- value already saved?
            strings[#strings+1] = saved[value] .. "\n"  -- use its previous name
        else
            saved[value] = name   -- save name for next time
            strings[#strings+1] = "{}\n"  -- create a new table

            for k,v in pairs(value) do      -- save its fields
                local fieldname = string.format("%s[%s]", name, basicSerialize(k))
                if (type(v)=="table" and not tmpgvtabs[v]) then
                    error("cannot save \""..name..
                          "\": gamevar tables may only contain tables that are also gamevars", 2)
                end
                save(fieldname, v, saved, strings)
            end
        end
    else
        error("cannot save \""..name.."\", a " .. type(value), 2)
    end
end

local function serializeGamevars()
    local saved = {}
    local strings = {}

    for gvname,_ in pairs(gamevarNames) do
        if (type(G_[gvname])=="table") then
            tmpgvtabs[G_[gvname]] = true
        end
    end

    -- TODO: catch errors in save()
    for gvname,_ in pairs(gamevarNames) do
        save(gvname, G_[gvname], saved, strings)
    end
    strings[#strings+1] = "\n"

    tmpgvtabs = {}

    return table.concat(strings)
end

local function loadGamevarsString(string)
    assert(loadstring(string))()
end

DBG_.serializeGamevars = serializeGamevars
DBG_.loadGamevarsString = loadGamevarsString


---=== Environment setup ===---

-- add new variables/functions living in the global environment
G_.DBG_ = DBG_  -- REMOVE this for release
G_.gv = gv
G_.sector = sector
G_.wall = wall
G_.sprite = sprite
G_.spriteext = spriteext
G_.headspritesect = headspritesect
G_.headspritestat = headspritestat
G_.nextspritesect = nextspritesect
G_.nextspritestat = nextspritestat
G_.prevspritesect = prevspritesect
G_.prevspritestat = prevspritestat

G_.actor = actor

-- functions
G_.spritesofsect = spritesofsect
G_.spritesofstat = spritesofstat
G_.sectorsofbunch = sectorsofbunch
G_.getbunch = getbunch

G_.TEMP_getvollev = TEMP_getvollev  -- REMOVE
G_.gamevar = gamevar

G_.setevent = setevent  -- included in lunatic.c


-- PiL 14.2 continued
setmetatable(
    G_, {
        __newindex = function (_, n)
            error("attempt to write to undeclared variable "..n, 2)
        end,
        __index = function (_, n)
            error("attempt to read undeclared variable "..n, 2)
        end,
        })

-- change the environment of the running Lua thread to the table G_
setfenv(0, G_)