show selection info (with -i option)

src/config.def.h

@@ -16,3 +16,4 @@
 #define DEFAULT_PROMPT "> "
 #define DEFAULT_NUM_LINES 10
 #define DEFAULT_WORKERS 0
+#define DEFAULT_SHOW_INFO 0

src/options.c

@@ -19,6 +19,7 @@ static const char *usage_str =
     " -s, --show-scores        Show the scores of each match\n"
     " -0, --read-null          Read input delimited by ASCII NUL characters\n"
     " -j, --workers NUM        Use NUM workers for searching. (default is # of CPUs)\n"
+    " -i, --show-info          Show selection info line\n"
     " -h, --help     Display this help and exit\n"
     " -v, --version  Output version information and exit\n";
 
@@ -36,6 +37,7 @@ static struct option longopts[] = {{"show-matches", required_argument, NULL, 'e'
 				   {"version", no_argument, NULL, 'v'},
 				   {"benchmark", optional_argument, NULL, 'b'},
 				   {"workers", required_argument, NULL, 'j'},
+				   {"show-info", no_argument, NULL, 'i'},
 				   {"help", no_argument, NULL, 'h'},
 				   {NULL, 0, NULL, 0}};
 
@@ -51,13 +53,14 @@ void options_init(options_t *options) {
 	options->prompt          = DEFAULT_PROMPT;
 	options->workers         = DEFAULT_WORKERS;
 	options->input_delimiter = '\n';
+	options->show_info       = DEFAULT_SHOW_INFO;
 }
 
 void options_parse(options_t *options, int argc, char *argv[]) {
 	options_init(options);
 
 	int c;
-	while ((c = getopt_long(argc, argv, "vhs0e:q:l:t:p:j:", longopts, NULL)) != -1) {
+	while ((c = getopt_long(argc, argv, "vhs0e:q:l:t:p:j:i", longopts, NULL)) != -1) {
 		switch (c) {
 			case 'v':
 				printf("%s " VERSION " © 2014-2018 John Hawthorn\n", argv[0]);
@@ -108,6 +111,9 @@ void options_parse(options_t *options, int argc, char *argv[]) {
 				}
 				options->num_lines = l;
 			} break;
+			case 'i':
+				options->show_info = 1;
+				break;
 			case 'h':
 			default:
 				usage(argv[0]);

src/options.h

@@ -12,6 +12,7 @@ typedef struct {
 	const char *prompt;
 	unsigned int workers;
 	char input_delimiter;
+	int show_info;
 } options_t;
 
 void options_init(options_t *options);

src/tty_interface.c

@@ -20,7 +20,7 @@ static void clear(tty_interface_t *state) {
 
 	tty_setcol(tty, 0);
 	size_t line = 0;
-	while (line++ < state->options->num_lines) {
+	while (line++ < state->options->num_lines + (state->options->show_info ? 1 : 0)) {
 		tty_newline(tty);
 	}
 	tty_clearline(tty);
@@ -90,9 +90,16 @@ static void draw(tty_interface_t *state) {
 			start = available - num_lines;
 		}
 	}
+
 	tty_setcol(tty, 0);
 	tty_printf(tty, "%s%s", options->prompt, state->search);
 	tty_clearline(tty);
+
+	if (options->show_info) {
+		tty_printf(tty, "\n[%lu/%lu]", choices->available, choices->size);
+		tty_clearline(tty);
+	}
+
 	for (size_t i = start; i < start + num_lines; i++) {
 		tty_printf(tty, "\n");
 		tty_clearline(tty);
@@ -101,14 +108,9 @@ static void draw(tty_interface_t *state) {
 			draw_match(state, choice, i == choices->selection);
 		}
 	}
-	if (num_lines > 0) {
-		tty_moveup(tty, num_lines);
-	}
 
-	tty_setcol(tty, 0);
-	fputs(options->prompt, tty->fout);
-	for (size_t i = 0; i < state->cursor; i++)
-		fputc(state->search[i], tty->fout);
+	tty_moveup(tty, num_lines + (options->show_info ? 1 : 0));
+	tty_setcol(tty, strlen(options->prompt) + state->cursor);
 	tty_flush(tty);
 }