add basic window functions, option parsing, and main loop

5 files changed, 396 insertions, 13 deletions

diff --git a/src/gl/honey_gl.c b/src/gl/honey_gl.c
index bbb775f..6a113d1 100644
--- a/src/gl/honey_gl.c
+++ b/src/gl/honey_gl.c
@@ -1,10 +1,197 @@
 #include <honeysuckle.h>
+
+#include <stdbool.h>
+
 #include "logging/logging.h"
 #include "gl/honey_gl.h"
 
-int honey_gl_window_ref = LUA_NOREF;
 
-bool honey_gl_setup()
+struct honey_window window;
+
+static int resize_callback_ref = LUA_NOREF;
+static int resize_data_ref = LUA_NOREF;
+
+static int focus_callback_ref = LUA_NOREF;
+static int focus_data_ref = LUA_NOREF;
+
+static void error_callback(int code, const char *description);
+static void resize_callback(GLFWwindow *w, int width, int height);
+static void focus_callback(GLFWwindow *w, int focus);
+
+static int create_window(lua_State *L);
+
+static int window_get_size(lua_State *L);
+static int window_set_size(lua_State *L);
+static int window_set_resize_callback(lua_State *L);
+static int window_unset_resize_callback(lua_State *L);
+
+
+void setup_window(lua_State *L, int tbl_index)
 {
-   return false;
+   /* initialize window struct */
+   window.created = false;
+   window.L = L;
+   
+   /* set error handler */
+   glfwSetErrorCallback(error_callback);
+
+   /* create window table */
+   hs_create_table
+      (L,
+       hs_str_cfunc("createWindow", create_window),
+       hs_str_cfunc("getSize", window_get_size),
+       hs_str_cfunc("setSize", window_set_size),
+       hs_str_cfunc("setResizeCallback", window_set_resize_callback),
+       hs_str_cfunc("unsetResizeCallback", window_unset_resize_callback)
+       );
+
+   /* set honey table entry */
+   lua_setfield(L, tbl_index, "window");
+}
+
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * glfw callbacks
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+static void error_callback(int code, const char *description)
+{
+   honey_error("GLFW error %d: %s", code, description);
+   hs_throw_error(window.L, "(GLFW error %d) %s", code, description);
+}
+
+
+static void resize_callback(GLFWwindow *w, int width, int height)
+{
+   lua_State *L = window.L;
+
+   if (resize_callback_ref == LUA_NOREF)
+      /* no resize callback set */
+      return;
+
+   /* push callback function */
+   hs_rload(L, resize_callback_ref);
+
+   lua_pushinteger(L, width);
+   lua_pushinteger(L, height);
+
+   if (resize_data_ref == LUA_NOREF || resize_data_ref == LUA_REFNIL)
+      lua_pushnil(L);
+   else
+      hs_rload(L, resize_data_ref);
+
+   hs_call(L, 3, 0);
+}
+
+
+static void focus_callback(GLFWwindow *w, int focus)
+{
+   lua_State *L = window.L;
+
+   if (focus_callback_ref == LUA_NOREF)
+      /* no focus callback set */
+      return;
+
+   /* push callback function */
+   hs_rload(L, focus_callback_ref);
+
+   lua_pushboolean(L, focus);
+
+   if (focus_data_ref == LUA_NOREF || focus_data_ref == LUA_REFNIL)
+      lua_pushnil(L);
+   else
+      hs_rload(L, focus_data_ref);
+
+   hs_call(L, 2, 0);
+}
+
+
+/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * window
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+static int create_window(lua_State *L)
+{
+   /* return immediately if already called */
+   if (window.created) return 0;
+   
+   lua_Integer x, y;
+   hs_parse_args(L, hs_int(x), hs_int(y));
+
+   if (!glfwInit()) {
+      /* window creation failed :c */
+      honey_fatal("failed to create window!");
+      hs_throw_error(L, "failed to create window!");
+   }
+
+   glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+   glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
+   glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
+
+   window.window = glfwCreateWindow(x, y, "honey", NULL, NULL);
+   glfwMakeContextCurrent(window.window);
+
+   if (!gladLoadGLLoader((GLADloadproc) glfwGetProcAddress)) {
+      honey_fatal("failed to initialize GLAD");
+      glfwTerminate();
+      hs_throw_error(L, "failed to initialize GLAD");
+   }
+
+   /* bind resize/focus callbacks */
+   glfwSetWindowSizeCallback(window.window, resize_callback);
+   glfwSetWindowFocusCallback(window.window, focus_callback);
+}
+
+
+static int window_get_size(lua_State *L)
+{
+   int width, height;
+   glfwGetWindowSize(window.window, &width, &height);
+   lua_pushinteger(L, width);
+   lua_pushinteger(L, height);
+   return 2;
+}
+
+
+static int window_set_size(lua_State *L)
+{
+   lua_Integer width, height;
+   hs_parse_args(L, hs_int(width), hs_int(height));
+   glfwSetWindowSize(window.window, width, height);
+   return 0;
+}
+
+
+static int window_set_resize_callback(lua_State *L)
+{
+   int cb, data;
+   hs_parse_args(L, hs_func(cb), hs_any(data));
+
+   lua_pushvalue(L, cb);
+   resize_callback_ref = hs_rstore(L);
+
+   lua_pushvalue(L, data);
+   resize_data_ref = hs_rstore(L);
+
+   return 0;
+}
+
+
+static int window_unset_resize_callback(lua_State *L)
+{
+   if (resize_callback_ref != LUA_NOREF)
+      hs_rdel(L, resize_callback_ref);
+   if (resize_data_ref != LUA_NOREF)
+      hs_rdel(L, resize_callback_ref);
+
+   resize_callback_ref = LUA_NOREF;
+   resize_data_ref = LUA_NOREF;
+
+   return 0;
 }
diff --git a/src/gl/honey_gl.h b/src/gl/honey_gl.h
index fc57037..8d5cdd9 100644
--- a/src/gl/honey_gl.h
+++ b/src/gl/honey_gl.h
@@ -1,18 +1,17 @@
 #ifndef HONEY_GL_H
 #define HONEY_GL_H
 
-#include <stdbool.h>
-
-#ifdef UNIT_TEST
-#include "test/mock/mock_GLFW.h"
-#else
 #include "glad/glad.h"
 #include <GLFW/glfw3.h>
-#endif
 
-extern int honey_gl_window_ref;
+struct honey_window {
+   GLFWwindow * window;
+   bool created;
+   lua_State *L;
+};
 
-bool honey_gl_setup();
+extern struct honey_window window;
 
+void setup_window(lua_State *L, int tbl_index);
 
 #endif
diff --git a/src/main.c b/src/main.c
index 8111ef8..e6311c2 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,7 +1,135 @@
 #include <stdio.h>
+#include <honeysuckle.h>
 
-int main()
+#include "logging/logging.h"
+#include "options/honey_options.h"
+#include "gl/honey_gl.h"
+
+static int get_func(lua_State *L, char *name);
+static void loop(lua_State *L, int update, int draw);
+
+
+int main(int argc, char **argv)
 {
-   printf("hello, world!\n");
+   /* process command-line options */
+   struct honey_options options;
+   if (!parse_options(&options, argc, argv))
+      return 1;
+   if (options.display_help)
+      /* help displayed, exit */
+      return 0;
+
+   honey_info("options:\n"
+	      "  main script: %s\n"
+	      "  log level: %s\n",
+	      options.main_script,
+	      honey_log_level_str(options.log_level));
+
+   /* setup lua environment */
+   honey_debug("initialize lua_State\n");
+   lua_State *L = luaL_newstate();
+   luaL_openlibs(L);
+
+   honey_debug("load honey bindings\n");
+   lua_createtable(L, 0, 1);
+   int index = lua_gettop(L);
+
+   setup_window(L, index);
+
+   lua_setglobal(L, "honey");
+
+   /* load main script */
+   honey_debug("loading '%s'\n", options.main_script);
+
+   if (luaL_loadfile(L, options.main_script)) {
+      const char *error = lua_tostring(L, -1);
+      honey_fatal("%s\n", error);
+      return 1;
+   }
+
+   if (!hs_call(L, 0, 0)) {
+      const char *error = lua_tostring(L, -1);
+      honey_fatal("unhandled error: %s", error);
+      goto close; /* sorry */
+   }
+
+   if (!window.created) {
+      lua_getglobal(L, "honey");
+      lua_getfield(L, -1, "window");
+      lua_getfield(L, -1, "createWindow");
+      lua_pushinteger(L, 640);
+      lua_pushinteger(L, 480);
+      hs_call(L, 2, 0);
+   }
+
+   int update = get_func(L, "update");
+   if (update) honey_info("honey.update: %s\n", lua_tostring(L, update));
+   else honey_info("honey.update: (nil)\n");
+   int draw   = get_func(L, "draw");
+   if (draw) honey_info("honey.draw: %s\n", lua_tostring(L, draw));
+   else honey_info("honey.draw: (nil)\n");
+
+   while(!glfwWindowShouldClose(window.window))
+      loop(L, update, draw);
+
+ close:
+   lua_close(L);
+   glfwTerminate();
+   
    return 0;
 }
+
+
+static int get_func(lua_State *L, char *name)
+{
+   lua_getglobal(L, "honey");
+   int index = lua_gettop(L);
+   lua_getfield(L, -1, name);
+
+   if (lua_isfunction(L, -1)) {
+      lua_remove(L, index);
+      return lua_gettop(L);
+   }
+   else {
+      lua_pop(L, 2);
+      return 0;
+   }
+}
+			
+
+static void loop(lua_State *L, int update, int draw)
+{
+   static float prev_time = 0;
+   static float draw_time = 0;
+
+   float current_time = (float) glfwGetTime();
+   float dt = current_time - prev_time;
+   prev_time = current_time;
+
+   draw_time += dt;
+   glfwPollEvents();
+
+   if (update) {
+      lua_pushvalue(L, update);
+      lua_pushnumber(L, dt);
+      if (!hs_call(L, 1, 0)) {
+	 /* error! */
+	 const char *error = lua_tostring(L, -1);
+	 honey_fatal("unhandled error: %s\n", error);
+	 glfwSetWindowShouldClose(window.window, 1);
+      }
+   }
+
+   /* cap framerate at 60fps */
+   if (draw && draw_time > 0.016) {
+      draw_time -= 0.016;
+      lua_pushvalue(L, draw);
+      if(!hs_call(L, 0, 0)) {
+	 /* error! */
+	 const char *error = lua_tostring(L, -1);
+	 honey_fatal("unhandled error: %s\n", error);
+	 glfwSetWindowShouldClose(window.window, 1);
+      }
+   }
+}
+   
diff --git a/src/options/honey_options.c b/src/options/honey_options.c
new file mode 100644
index 0000000..cf93588
--- /dev/null
+++ b/src/options/honey_options.c
@@ -0,0 +1,55 @@
+#include <stdio.h>
+#include <unistd.h> /* todo: create windows-compatible alternative */
+
+#include "options/honey_options.h"
+
+
+static void print_usage(const char *program_name)
+{
+   printf("Usage: %s [OPTIONS]\n"
+	  "  -v         Increase output verbosity (-vvv displays every log message)\n"
+	  "  -q         Decrease output verbosity (-qqq suppresses even fatal errors)\n"
+	  "  -h         Print this help message and exit\n"
+	  "  -s SCRIPT  Load SCRIPT as the entry point instead of 'main.lua'\n",
+	  program_name);
+}
+
+
+int parse_options(struct honey_options *opts, int argc, char **argv)
+{
+   opts->main_script = "main.lua";
+   opts->log_level = WARN;
+   opts->display_help = 0;
+
+   int opt;
+   const char *flags = "hqvs:";
+   while ((opt = getopt(argc, argv, flags)) != -1) {
+      switch (opt) {
+      case 'q':
+	 opts->log_level -= 1;
+	 break;
+
+      case 'v':
+	 opts->log_level += 1;
+	 break;
+
+      case 'h':
+	 print_usage(argv[0]);
+	 opts->display_help = 1;
+	 return 1;
+
+      case 's':
+	 opts->main_script = optarg;
+	 break;
+
+      default:
+	 print_usage(argv[0]);
+	 return 0;
+      }
+   }
+
+   honey_log_set_level(opts->log_level);
+   honey_log_set_file(stderr);
+
+   return 1;
+}
diff --git a/src/options/honey_options.h b/src/options/honey_options.h
new file mode 100644
index 0000000..5f4aded
--- /dev/null
+++ b/src/options/honey_options.h
@@ -0,0 +1,14 @@
+#ifndef HONEY_OPTIONS_H
+#define HONEY_OPTIONS_H
+
+#include "logging/logging.h"
+
+struct honey_options {
+   const char *main_script;
+   enum honey_log_level_t log_level;
+   int display_help;
+};
+
+int parse_options(struct honey_options *opts, int argc, char **argv);
+
+#endif