RaceBase.cpp

// This file is part of ClassicAPI.
//
// ClassicAPI is free software: you can redistribute it and/or modify it under the terms
// of the GNU Lesser General Public License as published by the Free Software Foundation, either
// version 3 of the License, or (at your option) any later version.
//
// ClassicAPI is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
// PURPOSE. See the GNU Lesser General Public License for more details.

#include "Game.h"
#include "Offsets.h"
#include "dbc/Lookup.h"

#include <cstdint>

namespace Unit::RaceBase {

namespace {

using ResolveUnitToken_t = void *(__fastcall *)(const char *token);

// `UnitRaceBase(unit) → (raceFile, raceID)` — returns the locale-
// independent race token (`"Human"`, `"Orc"`, `"Dwarf"`, `"NightElf"`,
// `"Scourge"`, `"Tauren"`, `"Gnome"`, `"Troll"`) plus the numeric
// raceID (1..8 in vanilla), or `(nil, nil)` if the unit can't be
// resolved.
//
// Sibling to `UnitClassBase` — same descriptor-byte + DBC.Filename
// chain, just reading `UNIT_FIELD_BYTES_0` byte 0 (race) instead of
// byte 1 (class) and looking up `ChrRaces.dbc::Filename` at `+0x3C`
// (locale-independent string, distinct from the localized `Name[9]`
// at `+0x44` that `UnitRace` already returns).
//
// Race byte is broadcast in UpdateField data, so this works for any
// synced unit token (player, target, party / raid, mouseover,
// inspect targets — anything FUN_RESOLVE_UNIT_TOKEN handles).
//
// Returns `(nil, nil)` for unresolvable units (empty target /
// party slot, unloaded descriptor), unit-byte 0 (uninitialized /
// NPC), or out-of-range race bytes (no matching ChrRaces.dbc row).
int __fastcall Script_UnitRaceBase(void *L) {
    if (!Game::Lua::IsString(L, 1)) {
        Game::Lua::Error(L, "Usage: UnitRaceBase(\"unit\")");
        return 0;
    }
    const char *token = Game::Lua::ToString(L, 1);
    if (token == nullptr) {
        Game::Lua::PushNil(L);
        Game::Lua::PushNil(L);
        return 2;
    }

    auto resolve = reinterpret_cast<ResolveUnitToken_t>(Offsets::FUN_RESOLVE_UNIT_TOKEN);
    auto *unit = static_cast<const uint8_t *>(resolve(token));
    if (unit == nullptr) {
        Game::Lua::PushNil(L);
        Game::Lua::PushNil(L);
        return 2;
    }
    auto *desc = *reinterpret_cast<const uint8_t *const *>(
        unit + Offsets::OFF_UNIT_DESCRIPTOR);
    if (desc == nullptr) {
        Game::Lua::PushNil(L);
        Game::Lua::PushNil(L);
        return 2;
    }
    const uint8_t raceByte = *(desc + Offsets::OFF_UNIT_DESCRIPTOR_RACE_BYTE);
    if (raceByte == 0) {
        Game::Lua::PushNil(L);
        Game::Lua::PushNil(L);
        return 2;
    }

    const char *raceFile = DBC::StringField(
        Offsets::VAR_CHRRACES_RECORDS,
        Offsets::VAR_CHRRACES_COUNT,
        raceByte,
        Offsets::OFF_CHRRACES_FILENAME);
    if (raceFile == nullptr) {
        Game::Lua::PushNil(L);
        Game::Lua::PushNil(L);
        return 2;
    }
    Game::Lua::PushString(L, raceFile);
    Game::Lua::PushNumber(L, static_cast<double>(raceByte));
    return 2;
}

void RegisterLuaFunctions() {
    Game::Lua::RegisterGlobalFunction("UnitRaceBase", &Script_UnitRaceBase);
}

const Game::ModuleAutoRegister _autoreg{&RegisterLuaFunctions};

} // namespace

} // namespace Unit::RaceBase