1 files changed, 120 insertions, 0 deletions
diff --git a/src/LuaApi.h b/src/LuaApi.h
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+++ b/src/LuaApi.h
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+//========================================================================
+// dng
+//------------------------------------------------------------------------
+// Copyright (c) 2022 Steph Enders <steph@senders.io>
+//
+// This software is provided 'as-is', without any express or implied
+// warranty. In no event will the authors be held liable for any damages
+// arising from the use of this software.
+//
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it
+// freely, subject to the following restrictions:
+//
+// 1. The origin of this software must not be misrepresented; you must not
+//    claim that you wrote the original software. If you use this software
+//    in a product, an acknowledgment in the product documentation would
+//    be appreciated but is not required.
+//
+// 2. Altered source versions must be plainly marked as such, and must not
+//    be misrepresented as being the original software.
+//
+// 3. This notice may not be removed or altered from any source
+//    distribution.
+//
+//========================================================================
+
+#ifndef DNG_LUA_API_H
+#define DNG_LUA_API_H
+
+#include "lua.hpp"
+#include <iostream>
+
+struct LState {
+  lua_State *onkeypress;
+  lua_State *onupdate;
+  lua_State *onintro;
+  lua_State *onwin;
+  lua_State *onloss;
+} typedef LState;
+
+const char *ON_KEYPRESS = "onKeyPress";
+const char *ON_UPDATE = "onUpdate";
+const char *ON_INTRO = "onIntro";
+const char *ON_WIN = "onWin";
+const char *ON_LOSS = "onLoss";
+
+LState *init_default(lua_State *L) {
+  auto *state = static_cast<LState *>(malloc(sizeof(LState)));
+
+  state->onkeypress = L;
+  state->onupdate = L;
+  state->onintro = L;
+  state->onwin = L;
+  state->onloss = L;
+
+  return state;
+}
+
+bool check_fn(lua_State *L, const char *fn) {
+  lua_getglobal(L, fn);
+  return lua_isfunction(L, -1);
+}
+
+void override_file_fns(lua_State *L, LState *state) {
+  if (check_fn(L, ON_KEYPRESS)) {
+    state->onkeypress = L;
+  }
+  if (check_fn(L, ON_UPDATE)) {
+    state->onupdate = L;
+  }
+  if (check_fn(L, ON_INTRO)) {
+    state->onintro = L;
+  }
+  if (check_fn(L, ON_WIN)) {
+    state->onwin = L;
+  }
+  if (check_fn(L, ON_LOSS)) {
+    state->onloss = L;
+  }
+}
+
+bool lua_dofn(lua_State *L, const char *fn) {
+  lua_getglobal(L, fn);
+  if (!lua_isfunction(L, -1)) {
+    std::cout << "[C] Error " << fn << " not function | not found" << std::endl;
+    return false;
+  }
+  lua_pcall(L, 0, 1, 0);
+  return true;
+}
+
+bool lua_dofn_with_number(lua_State *L, const char *fn, lua_Number num) {
+  lua_getglobal(L, fn);
+  if (!lua_isfunction(L, -1)) {
+    std::cout << "[C] Error " << fn << " not function | not found" << std::endl;
+    return false;
+  }
+  lua_pushnumber(L, num);
+  lua_pcall(L, 1, 1, 0);
+  return true;
+}
+
+bool lua_onkeypress(lua_State *L, int pressedKey) {
+  if (pressedKey == -1) {
+    return true;
+  }
+  return lua_dofn_with_number(L, "onKeyPress", pressedKey);
+}
+
+bool lua_onupdate(lua_State *L, float dt) {
+  return lua_dofn_with_number(L, "onUpdate", dt);
+}
+
+bool lua_onintro(lua_State *L) { return lua_dofn(L, "onIntro"); }
+
+bool lua_onwin(lua_State *L) { return lua_dofn(L, "onWin"); }
+
+bool lua_onloss(lua_State *L) { return lua_dofn(L, "onLoss"); }
+
+#endif // DNG_LUA_API_H