ReSkate/Extension/Plugins/plugin_api_services.cpp

#include "plugin_api.h"
#include "plugin_game.h"
#include "lua.h"
#include "lualib.h"
#include <algorithm>
#include <cmath>
#include <string>
#include <vector>

// General services a game layer in Lua reads and drives each tick: the skater's telemetry, stance
// and Bone Cam, the pad and keys, the free and pad-flown cameras, spectating, the session's world,
// the competition's stock physics, and skate.'s trick list and flick diagrams. None of them knows a
// throwdown mode; each checks its permission and the game (plugin_game.h) does the rest.
namespace dingosdk::plugins {
struct ServicesApi {
    static Game& game(Plugin& plugin) { return plugin.services_.game(); }
};
namespace {
Game& game_of(Plugin& plugin) { return ServicesApi::game(plugin); }
Plugin& plugin_of(lua_State* L) {
    auto& plugin = *static_cast<Plugin*>(lua_callbacks(L)->userdata);
    if (plugin.halted()) luaL_error(L, "the plugin was stopped");
    return plugin;
}
Plugin& allowed(lua_State* L, const char* permission, const char* what) {
    auto& plugin = plugin_of(L);
    if (!plugin.has(permission)) luaL_error(L, "%s needs the \"%s\" permission in reskate-plugin.json", what, permission);
    return plugin;
}
std::uint64_t id_at(lua_State* L, int index) {
    if (lua_isnumber(L, index)) return static_cast<std::uint64_t>(lua_tonumber(L, index));
    // Steam IDs come as strings: a Lua number cannot hold one exactly.
    const std::string text = luaL_checkstring(L, index);
    std::uint64_t out{};
    for (const char c : text) {
        if (c < '0' || c > '9' || out > (~0ULL - 9) / 10) luaL_argerror(L, index, "a Steam ID");
        out = out * 10 + static_cast<std::uint64_t>(c - '0');
    }
    return out;
}
int result(lua_State* L, const std::string& why) {
    lua_pushboolean(L, why.empty());
    if (why.empty()) return 1;
    lua_pushlstring(L, why.data(), why.size());
    return 2;
}
void field_number(lua_State* L, const char* name, double value) {
    lua_pushnumber(L, value);
    lua_setfield(L, -2, name);
}
void field_bool(lua_State* L, const char* name, bool value) {
    lua_pushboolean(L, value);
    lua_setfield(L, -2, name);
}
void field_vec(lua_State* L, const char* name, const Vec3& v) {
    lua_pushvector(L, v[0], v[1], v[2]);
    lua_setfield(L, -2, name);
}

// ---- skater --------------------------------------------------------------------------------------
// skater.telemetry(): the trainer's telemetry, its last jump, the physics watch and the bail's body.
int telemetry(lua_State* L) {
    auto& plugin = allowed(L, "skater.read", "reskate.skater.telemetry");
    const auto t = game_of(plugin).skater_telemetry(plugin.id());
    if (!t) {
        lua_pushnil(L);
        return 1;
    }
    lua_createtable(L, 0, 20);
    field_bool(L, "skater", t->skater);
    field_bool(L, "airborne", t->airborne);
    field_vec(L, "position", t->position);
    field_number(L, "heading", t->heading);
    field_number(L, "speed", t->speed);
    field_number(L, "vertical", t->vertical);
    field_number(L, "air_time", t->air_time);
    field_number(L, "height", t->height);
    field_number(L, "top_speed", t->top_speed);
    field_number(L, "physics_state", t->physics_state);
    lua_createtable(L, 0, 16);
    const auto& j = t->last;
    field_number(L, "serial", static_cast<double>(j.serial));
    field_number(L, "takeoff_speed", j.takeoff_speed);
    field_number(L, "takeoff_angle", j.takeoff_angle);
    field_number(L, "air_time", j.air_time);
    field_number(L, "height", j.height);
    field_number(L, "distance", j.distance);
    field_number(L, "drop", j.drop);
    field_number(L, "landing_speed", j.landing_speed);
    field_number(L, "spin", j.spin);
    field_number(L, "spin_rate", j.spin_rate);
    field_number(L, "flip", j.flip);
    field_number(L, "board_turn", j.board_turn);
    field_number(L, "state", j.state);
    field_vec(L, "takeoff", j.takeoff);
    field_vec(L, "landing", j.landing);
    lua_setfield(L, -2, "last");
    lua_createtable(L, 0, 9);
    const auto& w = t->watch;
    field_bool(L, "valid", w.valid);
    field_bool(L, "ragdoll_known", w.ragdoll_known);
    field_bool(L, "ragdoll", w.ragdoll);
    field_number(L, "state", w.state);
    field_number(L, "previous", w.previous);
    field_number(L, "previous_seconds", w.previous_seconds);
    field_number(L, "changes", static_cast<double>(w.changes));
    field_number(L, "wipeouts", static_cast<double>(w.wipeouts));
    field_number(L, "runouts", static_cast<double>(w.runouts));
    lua_setfield(L, -2, "watch");
    field_bool(L, "teleport_pending", t->teleport_pending);
    field_bool(L, "slam", t->slam);
    field_bool(L, "struck", t->struck);
    if (t->body) field_vec(L, "body", *t->body);
    return 1;
}
int goofy(lua_State* L) {
    auto& plugin = allowed(L, "skater.read", "reskate.skater.goofy");
    if (const auto g = game_of(plugin).stance_goofy()) lua_pushboolean(L, *g);
    else lua_pushnil(L);
    return 1;
}
// skater.bone_cam(word, ...): no words for its setting ("game", "on" or "off"), "status" its full
// status line, "bail" a bail to show, "ringing" "1" or "0", "game" "on"/"off" (a plugin's game
// wants it), or the `bonecam` console words.
int bone_cam(lua_State* L) {
    auto& plugin = allowed(L, "camera", "reskate.skater.bone_cam");
    std::vector<std::string> words;
    for (int i = 1, n = std::min(lua_gettop(L), 8); i <= n; ++i) {
        std::size_t length = 0;
        const char* word = luaL_checklstring(L, i, &length);
        words.emplace_back(word, std::min<std::size_t>(length, 32));
    }
    const auto text = game_of(plugin).bone_cam(plugin.id(), words);
    lua_pushlstring(L, text.data(), text.size());
    return 1;
}

// ---- input ---------------------------------------------------------------------------------------
// input.pad_bits(menu): XInput's button bits with LT 0x10000 and RT 0x20000, or nil without a pad;
// with `menu`, read while ReSkate's menu is open too.
int pad_bits(lua_State* L) {
    auto& plugin = allowed(L, "input", "reskate.input.pad_bits");
    if (const auto bits = game_of(plugin).pad_bits(lua_toboolean(L, 1) != 0)) lua_pushnumber(L, *bits);
    else lua_pushnil(L);
    return 1;
}
int key_code(lua_State* L, int index) {
    if (lua_isnumber(L, index)) {
        const int vk = static_cast<int>(lua_tonumber(L, index));
        if (vk < 1 || vk > 254) luaL_argerror(L, index, "a virtual key from 1 to 254");
        return vk;
    }
    const std::string name = luaL_checkstring(L, index);
    static const std::pair<const char*, int> names[] = {
        {"Enter", 13}, {"Backspace", 8}, {"Escape", 27}, {"End", 35}, {"Home", 36}, {"PageUp", 33}, {"PageDown", 34}, {"Space", 32},
        {"Shift", 16}, {"Ctrl", 17}, {"Alt", 18}, {"Tab", 9}, {"Left", 37}, {"Up", 38}, {"Right", 39}, {"Down", 40},
        {"[", 0xDB}, {"]", 0xDD}, {"LeftMouse", 1}, {"RightMouse", 2}, {"MiddleMouse", 4}};
    for (const auto& [n, vk] : names)
        if (name == n) return vk;
    if (name.size() == 1 && ((name[0] >= 'A' && name[0] <= 'Z') || (name[0] >= '0' && name[0] <= '9'))) return name[0];
    luaL_argerror(L, index, "a key name (A-Z, 0-9, Enter, Backspace, Escape, End, PageUp, PageDown, [, ], ...) or a virtual key");
    return 0;
}
int key(lua_State* L) {
    auto& plugin = allowed(L, "input", "reskate.input.key");
    lua_pushboolean(L, game_of(plugin).key_down(key_code(L, 1)));
    return 1;
}
int wheel(lua_State* L) {
    auto& plugin = allowed(L, "input", "reskate.input.wheel");
    lua_pushnumber(L, game_of(plugin).mouse_wheel());
    return 1;
}
// input.game_buttons(hidden, held, pause): the game buttons (XInput bits) kept from the game while
// asked, those held down for it, and all game input paused for half a second.
int game_buttons(lua_State* L) {
    auto& plugin = allowed(L, "input", "reskate.input.game_buttons");
    const auto mask = [&](int index) {
        const double v = luaL_optnumber(L, index, 0);
        if (!(v >= 0 && v <= 0xffff)) luaL_argerror(L, index, "a 16-bit button mask");
        return static_cast<std::uint16_t>(v);
    };
    game_of(plugin).game_buttons(plugin.id(), mask(1), mask(2), lua_toboolean(L, 3) != 0);
    return 0;
}
int input_allowed(lua_State* L) {
    auto& plugin = allowed(L, "input", "reskate.input.allowed");
    lua_pushboolean(L, game_of(plugin).input_allowed());
    return 1;
}
int focus(lua_State* L) {
    auto& plugin = allowed(L, "input", "reskate.input.focus");
    const auto f = game_of(plugin).input_focus();
    lua_createtable(L, 0, 3);
    field_bool(L, "focused", f.focused);
    field_bool(L, "interface_open", f.interface_open);
    field_bool(L, "gameplay", f.gameplay);
    return 1;
}

// ---- camera --------------------------------------------------------------------------------------
int free_camera(lua_State* L) {
    auto& plugin = allowed(L, "camera", "reskate.camera.free");
    return result(L, game_of(plugin).free_camera(plugin.id(), lua_toboolean(L, 1) != 0));
}
// camera.pad_flight(on): the free camera flown from the pad while placing things from the air (the
// bumpers or Q/E its height; the triggers stay the plugin's). Held by one plugin; released with it.
int pad_flight(lua_State* L) {
    auto& plugin = allowed(L, "camera", "reskate.camera.pad_flight");
    return result(L, game_of(plugin).pad_flight(plugin.id(), lua_toboolean(L, 1) != 0));
}

// ---- session -------------------------------------------------------------------------------------
int spectate(lua_State* L) {
    auto& plugin = allowed(L, "session.read", "reskate.session.spectate");
    game_of(plugin).spectate(lua_isnoneornil(L, 1) ? 0 : id_at(L, 1));
    return 0;
}
// session.world(): {world = id (a string; it changes with the map or session), barred = the local
// player's mods change scoring, map = the map's name}.
int world(lua_State* L) {
    auto& plugin = allowed(L, "session.read", "reskate.session.world");
    auto& g = game_of(plugin);
    lua_createtable(L, 0, 3);
    const auto id = std::to_string(g.world_id());
    lua_pushlstring(L, id.data(), id.size());
    lua_setfield(L, -2, "world");
    field_bool(L, "barred", g.world_barred());
    const auto map = g.world_map();
    lua_pushlstring(L, map.data(), map.size());
    lua_setfield(L, -2, "map");
    return 1;
}

// ---- physics -------------------------------------------------------------------------------------
// physics.competition(on): the game's stock physics while the local player competes (the player's
// own tuning comes back after); stock_ready(): the stock tuning has been read; prepare(): read it
// now, switching nothing.
int competition(lua_State* L) {
    auto& plugin = allowed(L, "skater.control", "reskate.physics.competition");
    game_of(plugin).competition(plugin.id(), lua_toboolean(L, 1) != 0);
    return 0;
}
int stock_ready(lua_State* L) {
    auto& plugin = allowed(L, "skater.control", "reskate.physics.stock_ready");
    lua_pushboolean(L, game_of(plugin).stock_physics_ready());
    return 1;
}
int prepare(lua_State* L) {
    auto& plugin = allowed(L, "skater.control", "reskate.physics.prepare");
    game_of(plugin).prepare_physics();
    return 0;
}

// ---- tricks --------------------------------------------------------------------------------------
// tricks.feed(on): skate.'s trick list, entry by entry, as trick_notes events while on.
int trick_feed(lua_State* L) {
    auto& plugin = allowed(L, "events.tricks", "reskate.tricks.feed");
    game_of(plugin).trick_feed(plugin.id(), lua_toboolean(L, 1) != 0);
    return 0;
}
// tricks.gesture(name): the flick diagram of a flip trick as skate. names it ({{x, y}, ...}: x to the
// left, y pulled back, the stick's gate the unit circle, a regular stance); empty until the game's
// gestures are read (the first call starts that) or for a trick without one.
int gesture(lua_State* L) {
    auto& plugin = allowed(L, "events.tricks", "reskate.tricks.gesture");
    std::size_t length = 0;
    const char* name = luaL_checklstring(L, 1, &length);
    const auto path = game_of(plugin).trick_gesture(std::string_view(name, std::min<std::size_t>(length, 96)));
    lua_createtable(L, static_cast<int>(path.size()), 0);
    for (std::size_t i = 0; i < path.size(); ++i) {
        lua_createtable(L, 2, 0);
        lua_pushnumber(L, path[i][0]);
        lua_rawseti(L, -2, 1);
        lua_pushnumber(L, path[i][1]);
        lua_rawseti(L, -2, 2);
        lua_rawseti(L, -2, static_cast<int>(i + 1));
    }
    return 1;
}

// Adds the functions to reskate.<table> (on top of the stack), making the table when there is none.
void into_table(lua_State* L, const char* table, std::initializer_list<std::pair<const char*, lua_CFunction>> functions) {
    lua_getfield(L, -1, table);
    if (!lua_istable(L, -1)) {
        lua_pop(L, 1);
        lua_createtable(L, 0, static_cast<int>(functions.size()));
        lua_pushvalue(L, -1);
        lua_setfield(L, -3, table);
    }
    lua_setreadonly(L, -1, false);
    for (const auto& [name, f] : functions) {
        lua_pushcfunction(L, f, name);
        lua_setfield(L, -2, name);
    }
    lua_setreadonly(L, -1, true);
    lua_pop(L, 1);
}
} // namespace

void install_services_api(Plugin&, lua_State* L) {
    into_table(L, "skater", {{"telemetry", telemetry}, {"goofy", goofy}, {"bone_cam", bone_cam}});
    into_table(L, "input", {{"pad_bits", pad_bits}, {"key", key}, {"wheel", wheel}, {"game_buttons", game_buttons}, {"allowed", input_allowed}, {"focus", focus}});
    into_table(L, "session", {{"spectate", spectate}, {"world", world}});
    into_table(L, "camera", {{"free", free_camera}, {"pad_flight", pad_flight}});
    into_table(L, "physics", {{"competition", competition}, {"stock_ready", stock_ready}, {"prepare", prepare}});
    into_table(L, "tricks", {{"feed", trick_feed}, {"gesture", gesture}});
}
} // namespace dingosdk::plugins