sheet: Give status msgs a priority which decays with time

Allows errors to be displayed for longer without them blocking other
status messages after the user has been given time to view them.

Possibly errors should be displayed in a separate buffer or location,
but while we are overloading the status this gives the user chance to
view them.

app/sheet.c

@@ -166,7 +166,8 @@ size_t display_data_rowcount(struct zsvsheet_display_dimensions *dims) {
   return dims->rows - dims->footer_span - dims->header_span;
 }
 
-char zsvsheet_status_text[256] = {0};
+static int zsvsheet_status_priority;
+static char zsvsheet_status_text[256];
 static void zsvsheet_display_status_text(const struct zsvsheet_display_dimensions *ddims) {
   // clear the entire line
   mvprintw(ddims->rows - ddims->footer_span, 0, "%-*s", (int)sizeof(zsvsheet_status_text), "");
@@ -177,15 +178,24 @@ static void zsvsheet_display_status_text(const struct zsvsheet_display_dimension
   attroff(A_REVERSE);
 }
 
-static void zsvsheet_priv_set_status(const struct zsvsheet_display_dimensions *ddims, int overwrite, const char *fmt,
+#define ZSVSHEET_STATUS_LOW_PRIO 1
+#define ZSVSHEET_STATUS_HIGH_PRIO 10
+
+static void zsvsheet_priv_set_status(const struct zsvsheet_display_dimensions *ddims, int priority, const char *fmt,
                                      ...) {
-  if (overwrite || !*zsvsheet_status_text) {
+  if (priority > zsvsheet_status_priority || !*zsvsheet_status_text) {
     va_list argv;
     va_start(argv, fmt);
     vsnprintf(zsvsheet_status_text, sizeof(zsvsheet_status_text), fmt, argv);
     va_end(argv);
     // note: if (n < (int)sizeof(zsvsheet_status_text)), then we just ignore
+    zsvsheet_status_priority = priority;
   }
+
+  // The priority decays with each call which is at least n times per second as set by halfdelay
+  if (zsvsheet_status_priority > 0)
+    zsvsheet_status_priority--;
+
   zsvsheet_display_status_text(ddims);
 }
 
@@ -331,7 +341,7 @@ char zsvsheet_handle_find_next(struct zsvsheet_ui_buffer *uib, const char *needl
     *update_buffer = zsvsheet_goto_input_raw_row(uib, zsvsheet_opts->found_rownum, header_span, ddims, (size_t)-1);
     return 1;
   }
-  zsvsheet_priv_set_status(ddims, 1, "Not found");
+  zsvsheet_priv_set_status(ddims, ZSVSHEET_STATUS_HIGH_PRIO, "Not found");
   return 0;
 }
 
@@ -394,11 +404,11 @@ static zsvsheet_status zsvsheet_open_file_handler(struct zsvsheet_proc_context *
   if ((err = zsvsheet_ui_buffer_open_file(filename, NULL, state->custom_prop_handler, di->ui_buffers.base,
                                           di->ui_buffers.current))) {
     if (err > 0)
-      zsvsheet_priv_set_status(di->dimensions, 1, "%s: %s", filename, strerror(err));
+      zsvsheet_priv_set_status(di->dimensions, ZSVSHEET_STATUS_HIGH_PRIO, "%s: %s", filename, strerror(err));
     else if (err < 0)
-      zsvsheet_priv_set_status(di->dimensions, 1, "Unexpected error");
+      zsvsheet_priv_set_status(di->dimensions, ZSVSHEET_STATUS_HIGH_PRIO, "Unexpected error");
     else
-      zsvsheet_priv_set_status(di->dimensions, 1, "Not found: %s", filename);
+      zsvsheet_priv_set_status(di->dimensions, ZSVSHEET_STATUS_HIGH_PRIO, "Not found: %s", filename);
     return zsvsheet_status_ignore;
   }
 no_input:
@@ -645,7 +655,7 @@ static void zsvsheet_check_buffer_worker_updates(struct zsvsheet_ui_buffer *ub,
                                                  struct zsvsheet_sheet_context *handler_state) {
   pthread_mutex_lock(&ub->mutex);
   if (ub->status)
-    zsvsheet_priv_set_status(display_dims, 1, ub->status);
+    zsvsheet_priv_set_status(display_dims, ZSVSHEET_STATUS_LOW_PRIO, ub->status);
   if (ub->index_ready && ub->dimensions.row_count != ub->index->row_count + 1) {
     ub->dimensions.row_count = ub->index->row_count + 1;
     handler_state->display_info.update_buffer = true;
@@ -741,7 +751,7 @@ int ZSV_MAIN_FUNC(ZSV_COMMAND)(int argc, const char *argv[], struct zsv_opts *op
     ch = getch();
 
     handler_state.display_info.update_buffer = false;
-    zsvsheet_priv_set_status(&display_dims, 1, "");
+    zsvsheet_priv_set_status(&display_dims, ZSVSHEET_STATUS_LOW_PRIO, "");
 
     if (ch != ERR) {
       status = zsvsheet_key_press(ch, &handler_state);
@@ -758,7 +768,8 @@ int ZSV_MAIN_FUNC(ZSV_COMMAND)(int argc, const char *argv[], struct zsv_opts *op
       struct zsvsheet_opts zsvsheet_opts = {0};
       if (read_data(&ub, NULL, current_ui_buffer->input_offset.row, current_ui_buffer->input_offset.col, header_span,
                     &zsvsheet_opts, custom_prop_handler)) {
-        zsvsheet_priv_set_status(&display_dims, 1, "Unexpected error!"); // to do: better error message
+        zsvsheet_priv_set_status(&display_dims, ZSVSHEET_STATUS_HIGH_PRIO,
+                                 "Unexpected error!"); // to do: better error message
         continue;
       }
     }

app/sheet/handlers.c

@@ -45,6 +45,7 @@ zsvsheet_status zsvsheet_set_status(struct zsvsheet_proc_context *ctx, const cha
   va_end(argv);
   // note: if (n < (int)sizeof(zsvsheet_status_text)), then we just ignore
   zsvsheet_display_status_text(state->display_info.dimensions);
+  zsvsheet_status_priority = ZSVSHEET_STATUS_HIGH_PRIO;
   return zsvsheet_status_ok;
 }