Start working on sdtui; implement line editing

src/sdtui.c

@@ -39,20 +39,15 @@
 
 
 #define KEY_ESCAPE  27                 /**< Curses doesn't define this. */
+#define KEY_VT      11                 /**< Ctrl-K */
+#define KEY_NAK     21                 /**< Ctrl-U */
+#define KEY_ETB     23                 /**< Ctrl-W */
+
+#define _(x)  x                        /**< Fake gettext, for now. */
 
 // --- Utilities ---------------------------------------------------------------
 
-static void
+/* TODO use iconv() wchar_t -> utf-8 */
-display (const gchar *format, ...)
-{
-	va_list ap;
-
-	va_start (ap, format);
-	vw_printw (stdscr, format, ap);
-	va_end (ap);
-	refresh ();
-}
-
 static gchar *
 wchar_to_mb (wchar_t ch)
 {
@@ -74,18 +69,6 @@ wchar_to_mb (wchar_t ch)
 	return buffer;
 }
 
-static const gchar *
-wchar_to_mb_escaped (wchar_t ch)
-{
-	switch (ch)
-	{
-	case L'\r':  return "\\r";
-	case L'\n':  return "\\n";
-	case L'\t':  return "\\t";
-	default:     return wchar_to_mb (ch);
-	}
-}
-
 static int
 poll_restart (struct pollfd *fds, nfds_t nfds, int timeout)
 {
@@ -96,6 +79,22 @@ poll_restart (struct pollfd *fds, nfds_t nfds, int timeout)
 	return ret;
 }
 
+static gsize
+utf8_offset (const gchar *s, gsize offset)
+{
+	return g_utf8_offset_to_pointer (s, offset) - s;
+}
+
+/** Wrapper for curses event data. */
+typedef struct curses_event            CursesEvent;
+
+struct curses_event
+{
+	wint_t  code;
+	guint   is_char : 1;
+	MEVENT  mouse;
+};
+
 // --- SIGWINCH ----------------------------------------------------------------
 
 static int g_winch_pipe[2];            /**< SIGWINCH signalling pipe. */
@@ -128,50 +127,195 @@ install_winch_handler (void)
 		g_old_winch_handler = oldact.sa_handler;
 }
 
-// --- Event handlers ----------------------------------------------------------
+// --- Application -------------------------------------------------------------
 
-typedef struct
+StardictDict *g_dict;                   //!< The current dictionary
+
+guint32 g_top_position;                 //!< Index of the topmost entry
+guint g_selected;                       //!< Offset to the selected entry
+
+GString *g_input;                       //!< The current search input
+guint g_input_pos;                      //!< Cursor position within input
+
+/** Initialize the application core. */
+static void
+app_init (const gchar *filename)
 {
-	wint_t  code;
+	GError *error;
-	guint   is_char : 1;
+	g_dict = stardict_dict_new (filename, &error);
-	MEVENT  mouse;
+	if (!g_dict)
+	{
+		g_printerr ("Error loading dictionary: %s\n", error->message);
+		exit (EXIT_FAILURE);
+	}
+
+	g_top_position = 0;
+	g_selected = 0;
+
+	g_input = g_string_new (NULL);
+	g_input_pos = 0;
+}
+
+/** Render the top bar. */
+static void
+app_redraw_top (void)
+{
+	mvprintw (0, 0, "%s: ", _("Search"));
+
+	int y, x;
+	getyx (stdscr, y, x);
+
+	gchar *input = g_locale_from_utf8 (g_input->str, -1, NULL, NULL, NULL);
+	g_return_if_fail (input != NULL);
+
+	addstr (input);
+	clrtoeol ();
+	g_free (input);
+
+	move (y, x + g_input_pos);
+	refresh ();
+}
+
+/** Redraw the dictionary view. */
+static void
+app_redraw_view (void)
+{
+	// TODO
+	refresh ();
+}
+
+/** Redraw everything. */
+static void
+app_redraw (void)
+{
+	app_redraw_view ();
+	app_redraw_top ();
 }
-CursesEvent;
 
 static gboolean
-process_curses_event (CursesEvent *event)
+app_process_curses_event (CursesEvent *event)
 {
+	/* g_utf8_offset_to_pointer() is too dumb to detect this */
+	g_assert (g_utf8_strlen (g_input->str, -1) >= g_input_pos);
+
 	if (!event->is_char)
 	{
 		switch (event->code)
 		{
 		case KEY_RESIZE:
-			display ("Screen has been resized to %u x %u\n",
+			// TODO adapt to the new window size, COLS, LINES
-				COLS, LINES);
+			app_redraw ();
 			break;
 		case KEY_MOUSE:
-			display ("Mouse event at (%d, %d), state %#lx\n",
+			// TODO move the item cursor, event->mouse.{x,y,bstate}
-				event->mouse.x, event->mouse.y, event->mouse.bstate);
+			break;
+
+		case KEY_LEFT:
+			if (g_input_pos > 0)
+			{
+				g_input_pos--;
+				app_redraw_top ();
+			}
+			break;
+		case KEY_RIGHT:
+			if (g_input_pos < g_utf8_strlen (g_input->str, -1))
+			{
+				g_input_pos++;
+				app_redraw_top ();
+			}
+			break;
+		case KEY_BACKSPACE:
+			if (g_input_pos > 0)
+			{
+				gchar *current = g_utf8_offset_to_pointer
+					(g_input->str, g_input_pos);
+				gchar *prev = g_utf8_prev_char (current);
+				g_string_erase (g_input, prev - g_input->str, current - prev);
+				g_input_pos--;
+				app_redraw_top ();
+			}
+			break;
+		case KEY_DC:
+			if (g_input_pos < g_utf8_strlen (g_input->str, -1))
+			{
+				gchar *current = g_utf8_offset_to_pointer
+					(g_input->str, g_input_pos);
+				g_string_erase (g_input, current - g_input->str,
+					g_utf8_next_char (current) - current);
+				app_redraw_top ();
+			}
 			break;
-		default:
-			display ("Keyboard event: non-character: %u\n",
-				event->code);
 		}
 		return TRUE;
 	}
 
-	display ("Keyboard event: character: '%s'\n",
+	switch (event->code)
-		wchar_to_mb_escaped (event->code));
-
-	if (event->code == L'q' || event->code == KEY_ESCAPE)
 	{
-		display ("Quitting...\n");
+	case KEY_ESCAPE:
 		return FALSE;
+	case KEY_VT:  // Ctrl-K -- delete until the end of line
+		g_string_erase (g_input, utf8_offset (g_input->str, g_input_pos), -1);
+		app_redraw_top ();
+		return TRUE;
+	case KEY_ETB: // Ctrl-W -- delete word before cursor
+	{
+		if (!g_input_pos)
+			return TRUE;
+
+		gchar *current = g_utf8_offset_to_pointer (g_input->str, g_input_pos);
+		gchar *space = g_utf8_strrchr (g_input->str,
+			g_utf8_prev_char (current) - g_input->str, ' ');
+
+		if (space)
+		{
+			space = g_utf8_next_char (space);
+			g_string_erase (g_input, space - g_input->str, current - space);
+			g_input_pos = g_utf8_pointer_to_offset (g_input->str, space);
 		}
+		else
+		{
+			g_string_erase (g_input, 0, current - g_input->str);
+			g_input_pos = 0;
+		}
+
+		app_redraw_top ();
+		return TRUE;
+	}
+	case KEY_NAK: // Ctrl-U -- delete everything before the cursor
+		g_string_erase (g_input, 0, utf8_offset (g_input->str, g_input_pos));
+		g_input_pos = 0;
+		app_redraw_top ();
+		return TRUE;
+	}
+
+	/* What can you do... wchar_t, utf-8, locale encoding... */
+	gchar *letter = g_locale_to_utf8 (wchar_to_mb (event->code),
+		-1, NULL, NULL, NULL);
+	g_return_val_if_fail (letter != NULL, FALSE);
+
+	if (g_unichar_isprint (g_utf8_get_char (letter)))
+	{
+		g_string_insert (g_input,
+			utf8_offset (g_input->str, g_input_pos), letter);
+		g_input_pos += g_utf8_strlen (letter, -1);
+
+		app_redraw_top ();
+	}
+	g_free (letter);
 
 	return TRUE;
 }
 
+/** Free any resources used by the application. */
+static void
+app_destroy (void)
+{
+	g_string_free (g_input, TRUE);
+	g_object_unref (g_dict);
+}
+
+// --- Event handlers ----------------------------------------------------------
+
 static gboolean
 process_stdin_input (void)
 {
@@ -184,7 +328,7 @@ process_stdin_input (void)
 		if (sta == KEY_CODE_YES && event.code == KEY_MOUSE
 			&& getmouse (&event.mouse) == ERR)
 			abort ();
-		if (!process_curses_event (&event))
+		if (!app_process_curses_event (&event))
 			return FALSE;
 	}
 
@@ -214,33 +358,48 @@ main (int argc, char *argv[])
 		abort ();
 
 	GError *error = NULL;
-	GOptionContext *ctx = g_option_context_new ("- StarDict terminal UI");
+	GOptionContext *ctx = g_option_context_new
+		("dictionary.ifo - StarDict terminal UI");
 	g_option_context_add_main_entries (ctx, entries, NULL);
 	if (!g_option_context_parse (ctx, &argc, &argv, &error))
 	{
-		g_printerr ("Error: option parsing failed: %s\n", error->message);
+		g_printerr ("%s: %s: %s\n", _("Error"), _("option parsing failed"),
+			error->message);
 		exit (EXIT_FAILURE);
 	}
 
+	if (argc != 2)
+	{
+		gchar *help = g_option_context_get_help (ctx, TRUE, FALSE);
+		g_printerr ("%s", help);
+		g_free (help);
+		exit (EXIT_FAILURE);
+	}
+
+	g_option_context_free (ctx);
+
+	app_init (argv[1]);
+
 	if (!initscr ()
 	 || cbreak () == ERR
-	 || noecho () == ERR)
+	 || noecho () == ERR
+	 || nonl () == ERR)
 		abort ();
 
 	keypad (stdscr, TRUE);                /* Enable character processing. */
 	nodelay (stdscr, TRUE);               /* Don't block on get_wch(). */
+	scrollok (stdscr, TRUE);              /* Also scrolling, pretty please. */
 
-	mousemask (ALL_MOUSE_EVENTS, NULL);
+	setscrreg (1, LINES - 1);             /* Create a scroll region. */
-
+	mousemask (ALL_MOUSE_EVENTS, NULL);   /* Register mouse events. */
-	display ("Press Q, Escape or ^C to quit\n");
 
 	if (pipe (g_winch_pipe) == -1)
 		abort ();
-
 	install_winch_handler ();
 
-// --- Message loop ------------------------------------------------------------
+	app_redraw ();
 
+	/* Message loop. */
 	struct pollfd pollfd[2];
 
 	pollfd[0].fd = fileno (stdin);
@@ -257,13 +416,12 @@ main (int argc, char *argv[])
 		 && !process_stdin_input ())
 			break;
 		if ((pollfd[1].revents & POLLIN)
-		 && !process_winch_input (pollfd[2].fd))
+		 && !process_winch_input (pollfd[1].fd))
 			break;
 	}
 
-// --- Cleanup -----------------------------------------------------------------
-
 	endwin ();
+	app_destroy ();
 
 	if (close (g_winch_pipe[0]) == -1
 	 || close (g_winch_pipe[1]) == -1)