Quick view: show images on terminals with inline graphics (iTerm2, kitty protocols)

doc/man/mc.1.in

@@ -3683,6 +3683,20 @@ and that is the default value.
 Controls if scrolling with the mouse is done by pages or line by line
 on the internal file viewer.
 .TP
+.I quickview_image_protocol
+Selects how images are shown in the quick view panel.  Possible values are:
+.B auto
+(default; detect the terminal from the environment),
+.B iterm2
+(iTerm2 inline images protocol, used by iTerm2, WezTerm and others; all
+image formats supported by the terminal),
+.B kitty
+(kitty graphics protocol, used by kitty, Ghostty and others; PNG files
+only) and
+.B none
+(never show images).  Explicitly selected protocol is used even if the
+terminal can't be detected, but never inside tmux or screen.
+.TP
 .I only_leading_plus_minus
 Allow special treatment for '+', '\-', '*' in the command line (select,
 unselect, reverse selection) only if the command line is empty.  You

src/setup.c

@@ -419,6 +419,7 @@ static const struct
     { "editor_stop_format_chars", &edit_options.stop_format_chars, "-+*\\,.;:&>" },
 #endif
     { "mcview_eof", &mcview_show_eof, "" },
+    { "quickview_image_protocol", &mcview_image_protocol, "auto" },
     { NULL, NULL, NULL },
 };
 

src/viewer/Makefile.am

@@ -10,6 +10,7 @@ libmcviewer_la_SOURCES = \
 	display.c \
 	growbuf.c \
 	hex.c \
+	image.c \
 	internal.h \
 	lib.c \
 	mcviewer.c \

src/viewer/actions_cmd.c

@@ -719,6 +719,7 @@ mcview_callback (Widget *w, Widget *sender, widget_msg_t msg, int parm, void *da
             if (mc_global.midnight_shutdown)
                 mcview_ok_to_quit (view);
         }
+        mcview_image_forget (view, FALSE);
         mcview_done (view);
         mcview_remove_ext_script (view);
         return MSG_HANDLED;

src/viewer/display.c

@@ -237,6 +237,16 @@ mcview_update (WView *view)
 void
 mcview_display (WView *view)
 {
+    if (mcview_image_active (view))
+    {
+        mcview_display_clean (view);
+        mcview_display_status (view);
+        mcview_image_draw (view);
+        return;
+    }
+
+    mcview_image_forget (view, TRUE);
+
     if (view->mode_flags.hex)
         mcview_display_hex (view);
     else