Implement InputString.Inputs and InputString.Converts

Used in Rance Quest.

Presumably, Inputs() returns true when there is unconverted text in IME,
and Converts() returns whether the user is in the conversion phase of
IME input.

SDL text input API cannot distinguish them, so in this implementation
both return true when there is uncommitted text.

src/hll/InputString.c

@@ -28,6 +28,7 @@
 static int font_size;
 static int font_weight;
 static Point pos;
+static bool has_editing_text;
 
 static struct string *result;
 
@@ -72,29 +73,43 @@ static void handle_input(const char *text)
 	char *u = utf2sjis(text, 0);
 	string_append_cstr(&result, u, strlen(u));
 	free(u);
+	has_editing_text = false;
 }
 
 // TODO: This function has to draw the text at the given coordinates/size/weight.
 //       Need some kind of interface for creating textures that are always rendered
 //       on top of the scene. Should ideally be independent of SACT.
-//static void handle_editing(const char *text, int start, int length)
-//{
-//}
+static void handle_editing(const char *text, int start, int length)
+{
+	has_editing_text = *text != '\0';
+}
 
 static void InputString_OpenIME(void)
 {
 	register_input_handler(handle_input);
-//	register_editing_handler(handle_editing);
+	register_editing_handler(handle_editing);
+	has_editing_text = false;
 	SDL_StartTextInput();
 }
 
 static void InputString_CloseIME(void)
 {
 	SDL_StopTextInput();
+	has_editing_text = false;
 	clear_input_handler();
 	clear_editing_handler();
 }
 
+static bool InputString_Inputs(void)
+{
+	return has_editing_text;
+}
+
+static bool InputString_Converts(void)
+{
+	return has_editing_text;
+}
+
 HLL_LIBRARY(InputString,
 	    HLL_EXPORT(SetFont, InputString_SetFont),
 	    HLL_EXPORT(SetPos, InputString_SetPos),
@@ -103,4 +118,6 @@ HLL_LIBRARY(InputString,
 	    HLL_EXPORT(OpenIME, InputString_OpenIME),
 	    HLL_EXPORT(CloseIME, InputString_CloseIME),
 	    HLL_EXPORT(GetResultString, InputString_GetResultString),
-	    HLL_EXPORT(ClearResultString, InputString_ClearResultString));
+	    HLL_EXPORT(ClearResultString, InputString_ClearResultString),
+	    HLL_EXPORT(Inputs, InputString_Inputs),
+	    HLL_EXPORT(Converts, InputString_Converts));