support "default colors"master-fmsbw-ci

* The terminal's default foreground and background colors
  are now used by default (`sciteco --no-profile`), so SciTECO
  integrates naturally into all terminal color schemes, even
  dark-on-bright ones.
* The default Scintilla colors use only 0x000000 (COLOR_BLACK) and 0xC0C0C0 (COLOR_WHITE)
  now.
* You can use `7EJ` to configure the default colors in color
  schemes or your profile.
  All existing color schemes had to disable default colors
  (`-1,-1,7EJ`) since they wouldn't look well otherwise.
* You may add `-1,7EJ` to ~/.teco_ini when using a terminal emulator
  with a washed-out palettized COLOR_BLACK.
  We cannot detect the terminal's default colors automatically.
* Scinterm updated to v6.0.
  We require a not-yet-upstreamed patch:
  https://github.com/orbitalquark/scinterm/pull/40
* In fact, we might decide not to support default colors at all in Scinterm,
  so this feature should be considered experimental.

1 files changed, 103 insertions, 67 deletions

diff --git a/src/interface-curses/interface.c b/src/interface-curses/interface.c
index 21e728f..ff6a0f2 100644
--- a/src/interface-curses/interface.c
+++ b/src/interface-curses/interface.c
@@ -200,6 +200,12 @@ static struct {
 	 * so every color is initialized to exact RGB values.
 	 */
 	gboolean use_palette;
+	/**
+	 * Scintilla RGB values which should be rendered
+	 * as the terminal's default foreground/background colors.
+	 * This is -1 if colors haven't been configured.
+	 */
+	gint32 default_fg, default_bg;
 
 	int stdin_orig, stdout_orig, stderr_orig;
 	SCREEN *screen;
@@ -237,58 +243,6 @@ static struct {
 } teco_interface;
 
 /**
- * Returns the curses color pair for the given curses foreground and background colors.
- * Initializes a new pair if necessary.
- *
- * Scinterm no longer initializes all color pairs for all combinations of
- * the builtin foreground and background colors.
- * Since curses does not guarantee any number of color pairs, we cannot do that either.
- * Instead we allocate color pairs in the first half of
- * color pair space on demand, while the second half is reserved to Scinterm.
- *
- * @param attr attributes to modify (for supporting monochrome terminals)
- * @param fg curses foreground color
- * @param bg curses background color
- * @return curses color pair number
- */
-static gshort
-teco_color_pair(attr_t *attr, gshort fg, gshort bg)
-{
-	static guint next_pair = 1;
-
-	/*
-	 * Basic support for monochrome terminals:
-	 * Every background, that is not black is assumed to be a
-	 * dark-on-bright area, rendered in reverse.
-	 * This will at least work with the terminal.tes and contrast.tes
-	 * color schemes.
-	 */
-	if (!has_colors()) {
-		if (bg != COLOR_BLACK)
-			*attr |= WA_REVERSE;
-		return 0;
-	}
-
-	G_STATIC_ASSERT(sizeof(gshort)*2 <= sizeof(guint));
-	gpointer key = GUINT_TO_POINTER(((guint)fg << 8*sizeof(bg)) | bg);
-	gpointer value = g_hash_table_lookup(teco_interface.pair_table, key);
-	if (G_LIKELY(value != NULL))
-		return GPOINTER_TO_UINT(value);
-	if (G_UNLIKELY(next_pair >= MAX_PAIRS))
-		return 0;
-	init_pair(next_pair, fg, bg);
-	g_hash_table_insert(teco_interface.pair_table, key, GUINT_TO_POINTER(next_pair));
-	return next_pair++;
-}
-
-static inline gint
-teco_wattr_set(WINDOW *win, attr_t attr, gshort fg, gshort bg)
-{
-	gshort pair = teco_color_pair(&attr, fg, bg);
-	return wattr_set(win, attr, pair, NULL);
-}
-
-/**
  * Translate a Scintilla-compatible RGB color value
  * (0xBBGGRR) to a Curses color triple (0 to 1000
  * for each component).
@@ -358,6 +312,72 @@ teco_rgb2curses(guint32 rgb)
 	return next_color;
 }
 
+/**
+ * Returns the curses color pair for the given curses foreground and background colors.
+ * Initializes a new pair if necessary.
+ *
+ * Scinterm no longer initializes all color pairs for all combinations of
+ * the builtin foreground and background colors.
+ * Since curses does not guarantee any number of color pairs, we cannot do that either.
+ * Instead we allocate color pairs in the first half of
+ * color pair space on demand, while the second half is reserved to Scinterm.
+ *
+ * @param attr attributes to modify (for supporting monochrome terminals)
+ * @param fg curses foreground color (0xBBGGRR)
+ * @param bg curses background color (0xBBGGRR)
+ * @return curses color pair number
+ */
+static gshort
+teco_color_pair(attr_t *attr, guint32 fg, guint32 bg)
+{
+	static guint next_pair = 1;
+
+	/*
+	 * Basic support for monochrome terminals:
+	 * Every background, that is not black is assumed to be a
+	 * dark-on-bright area, rendered in reverse.
+	 * This will at least work with the terminal.tes and contrast.tes
+	 * color schemes.
+	 */
+	if (!has_colors()) {
+		if (bg != 0x000000)
+			*attr ^= WA_REVERSE;
+		return 0;
+	}
+
+	gshort fg_id, bg_id;
+
+	/*
+	 * Prefer to use reverse attribute since it will work with
+	 * the terminals default colors.
+	 */
+	if (fg == teco_interface.default_bg && bg == teco_interface.default_fg) {
+		fg_id = bg_id = -1;
+		*attr ^= WA_REVERSE;
+	} else {
+		fg_id = fg == teco_interface.default_fg ? -1 : teco_rgb2curses(fg);
+		bg_id = bg == teco_interface.default_bg ? -1 : teco_rgb2curses(bg);
+	}
+
+	G_STATIC_ASSERT(sizeof(gshort)*2 <= sizeof(guint));
+	gpointer key = GUINT_TO_POINTER(((guint)fg_id << 8*sizeof(bg_id)) | bg_id);
+	gpointer value = g_hash_table_lookup(teco_interface.pair_table, key);
+	if (G_LIKELY(value != NULL))
+		return GPOINTER_TO_UINT(value);
+	if (G_UNLIKELY(next_pair >= MAX_PAIRS))
+		return 0;
+	init_pair(next_pair, fg_id, bg_id);
+	g_hash_table_insert(teco_interface.pair_table, key, GUINT_TO_POINTER(next_pair));
+	return next_pair++;
+}
+
+static inline gint
+teco_wattr_set(WINDOW *win, attr_t attr, guint32 fg, guint32 bg)
+{
+	gshort pair = teco_color_pair(&attr, fg, bg);
+	return wattr_set(win, attr, pair, NULL);
+}
+
 static gint
 teco_xterm_version(void)
 {
@@ -461,6 +481,8 @@ void
 teco_interface_init(gint argc, gchar **argv)
 {
 	teco_interface.use_palette = TRUE;
+	teco_interface.default_fg = 0xC0C0C0; /* white */
+	teco_interface.default_bg = 0x000000; /* black */;
 
 	teco_interface.stdin_orig = teco_interface.stdout_orig = teco_interface.stderr_orig = -1;
 
@@ -506,7 +528,13 @@ void
 teco_interface_disable_palette(void)
 {
 	teco_interface.use_palette = FALSE;
-	scintilla_disable_color_palette();
+}
+
+void
+teco_interface_set_default_colors(gint32 fg, gint32 bg)
+{
+	teco_interface.default_fg = fg;
+	teco_interface.default_bg = bg;
 }
 
 #ifdef CURSES_TTY
@@ -652,6 +680,14 @@ teco_interface_init_interactive(GError **error)
 	teco_interface.pair_table = g_hash_table_new(g_direct_hash, g_direct_equal);
 	start_color();
 	scintilla_set_color_offsets(MAX_COLORS, MAX_PAIRS);
+	if (!teco_interface.use_palette)
+		scintilla_disable_color_palette();
+#ifdef HAVE_USE_DEFAULT_COLORS
+	/* color -1 will be the terminal's default foreground or background color */
+	use_default_colors();
+#endif
+	scintilla_set_default_colors(teco_interface.default_fg,
+	                             teco_interface.default_bg);
 
 	if (teco_interface.use_palette && has_colors()) {
 		teco_interface_insert_color(0x000000, COLOR_BLACK);
@@ -851,23 +887,23 @@ teco_interface_msg_literal(teco_msg_t type, const gchar *str, gsize len)
 	teco_interface_stdio_msg(type, str, len);
 #endif
 
-	gshort fg, bg;
+	guint32 fg, bg;
 
-	fg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETBACK, STYLE_DEFAULT, 0));
+	fg = teco_interface_ssm(SCI_STYLEGETBACK, STYLE_DEFAULT, 0);
 
 	switch (type) {
 	default:
 	case TECO_MSG_USER:
-		bg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETFORE, STYLE_DEFAULT, 0));
+		bg = teco_interface_ssm(SCI_STYLEGETFORE, STYLE_DEFAULT, 0);
 		break;
 	case TECO_MSG_INFO:
-		bg = COLOR_GREEN;
+		bg = 0x008000; /* green */
 		break;
 	case TECO_MSG_WARNING:
-		bg = COLOR_YELLOW;
+		bg = 0x008080; /* yellow */
 		break;
 	case TECO_MSG_ERROR:
-		bg = COLOR_RED;
+		bg = 0x000080; /* red */
 		beep();
 		break;
 	}
@@ -884,8 +920,8 @@ teco_interface_msg_clear(void)
 	if (!teco_interface.input_pad) /* batch mode */
 		return;
 
-	gshort fg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETBACK, STYLE_DEFAULT, 0));
-	gshort bg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETFORE, STYLE_DEFAULT, 0));
+	guint32 fg = teco_interface_ssm(SCI_STYLEGETBACK, STYLE_DEFAULT, 0);
+	guint32 bg = teco_interface_ssm(SCI_STYLEGETFORE, STYLE_DEFAULT, 0);
 
 	wmove(teco_interface.msg_window, 0, 0);
 	teco_wattr_set(teco_interface.msg_window, 0, fg, bg);
@@ -1077,8 +1113,8 @@ teco_interface_draw_info(void)
 	 * the current buffer's STYLE_DEFAULT.
 	 * The same style is used for MSG_USER messages.
 	 */
-	gshort fg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETBACK, STYLE_DEFAULT, 0));
-	gshort bg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETFORE, STYLE_DEFAULT, 0));
+	guint32 fg = teco_interface_ssm(SCI_STYLEGETBACK, STYLE_DEFAULT, 0);
+	guint32 bg = teco_interface_ssm(SCI_STYLEGETFORE, STYLE_DEFAULT, 0);
 
 	wmove(teco_interface.info_window, 0, 0);
 	teco_wattr_set(teco_interface.info_window, 0, fg, bg);
@@ -1650,8 +1686,8 @@ teco_interface_popup_show(gsize prefix_len)
 		/* batch mode */
 		return;
 
-	gshort fg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETFORE, STYLE_CALLTIP, 0));
-	gshort bg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETBACK, STYLE_CALLTIP, 0));
+	guint32 fg = teco_interface_ssm(SCI_STYLEGETFORE, STYLE_CALLTIP, 0);
+	guint32 bg = teco_interface_ssm(SCI_STYLEGETBACK, STYLE_CALLTIP, 0);
 
 	teco_interface.popup_prefix_len = prefix_len;
 	attr_t attr = 0;
@@ -1856,8 +1892,8 @@ teco_interface_process_mevent(MEVENT *event, GError **error)
 		else if (event->bstate & BUTTON_NUM(5))
 			teco_curses_info_popup_scroll(&teco_interface.popup, +2);
 
-		gshort fg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETFORE, STYLE_CALLTIP, 0));
-		gshort bg = teco_rgb2curses(teco_interface_ssm(SCI_STYLEGETBACK, STYLE_CALLTIP, 0));
+		guint32 fg = teco_interface_ssm(SCI_STYLEGETFORE, STYLE_CALLTIP, 0);
+		guint32 bg = teco_interface_ssm(SCI_STYLEGETBACK, STYLE_CALLTIP, 0);
 		attr_t attr = 0;
 		gshort pair = teco_color_pair(&attr, fg, bg);
 		teco_curses_info_popup_show(&teco_interface.popup, attr, pair);