[filter] display the number of filters

docs/source/ui.rst

@@ -41,7 +41,16 @@ Above and below the main body are status lines that display:
 * the current view;
 * the line number for the top line in the display;
 * the current search hit and the total number of hits;
-* the number of lines that are **not** displayed because of filtering.
+
+If the view supports filtering, there will be a status line showing the
+following:
+
+  * the number of enabled filters and the total number of filters;
+  * the number of lines that are **not** displayed because of filtering.
+
+To edit the filters, you can press TAB to change the focus from the main
+view to the filter editor.  The editor allows you to create, enable/disable,
+and delete filters easily.
 
 Finally, the last line on the display is where you can enter search
 patterns and execute internal commands, such as converting a

src/filter_status_source.cc

@@ -32,7 +32,7 @@
 #include "lnav.hh"
 #include "filter_status_source.hh"
 
-static auto TOGGLE_MSG = "Press(" ANSI_BOLD("TAB") ") to edit ";
+static auto TOGGLE_MSG = "Press " ANSI_BOLD("TAB") " to edit ";
 static auto HOTKEY_HELP =
     ANSI_BOLD("SPC") ": Enable/Disable | "
     ANSI_BOLD("ENTER") ": Edit | "
@@ -49,7 +49,10 @@ filter_status_source::filter_status_source()
     this->tss_fields[TSF_STITCH_TITLE].set_stitch_value(
         view_colors::ansi_color_pair_index(COLOR_BLUE, COLOR_WHITE));
 
-    this->tss_fields[TSF_FILTERED].set_width(20);
+    this->tss_fields[TSF_COUNT].set_width(22);
+    this->tss_fields[TSF_COUNT].set_role(view_colors::VCR_STATUS);
+
+    this->tss_fields[TSF_FILTERED].set_width(30);
     this->tss_fields[TSF_FILTERED].set_role(view_colors::VCR_BOLD_STATUS);
 
     this->tss_fields[TSF_HELP].right_justify(true);
@@ -76,6 +79,31 @@ size_t filter_status_source::statusview_fields()
     }
 
     if (this->tss_prompt.empty() && this->tss_error.empty()) {
+        lnav_data.ld_view_stack.top() | [this] (auto tc) {
+            text_sub_source *tss = tc->get_sub_source();
+            if (tss == nullptr) {
+                return;
+            }
+
+            filter_stack &fs = tss->get_filters();
+            auto enabled_count = 0, filter_count = 0;
+
+            for (const auto &tf : fs) {
+                if (tf->is_enabled()) {
+                    enabled_count += 1;
+                }
+                filter_count += 1;
+            }
+            if (filter_count == 0) {
+                this->tss_fields[TSF_COUNT].set_value("");
+            } else {
+                this->tss_fields[TSF_COUNT].set_value(
+                    " " ANSI_BOLD("%d")
+                    " of " ANSI_BOLD("%d")
+                    " enabled ", enabled_count, filter_count);
+            }
+        };
+
         return TSF__MAX;
     }
 
@@ -122,6 +150,6 @@ void filter_status_source::update_filtered(text_sub_source *tss)
             this->bss_last_filtered_count = tss->get_filtered_count();
             timer.start_fade(this->bss_filter_counter, 3);
         }
-        sf.set_value("%'9d Not Shown", tss->get_filtered_count());
+        sf.set_value("%'9d Lines not shown", tss->get_filtered_count());
     }
 }

src/help.txt

@@ -143,8 +143,17 @@ Above and below the main body are status lines that display:
   * the current view;
   * the line number for the top line in the display;
   * the current search hit and the total number of hits;
+
+If the view supports filtering, there will be a status line showing the
+following:
+
+  * the number of enabled filters and the total number of filters;
   * the number of lines not displayed because of filtering.
 
+To edit the filters, you can press TAB to change the focus from the main
+view to the filter editor.  The editor allows you to create, enable/disable,
+and delete filters easily.
+
 Finally, the last line on the display is where you can enter search
 patterns and execute internal commands, such as converting a
 unix-timestamp into a human-readable date.  The command-line is

src/hotkeys.cc

@@ -110,6 +110,7 @@ void handle_paging_key(int ch)
     textview_curses *tc = *lnav_data.ld_view_stack.top();
     exec_context &ec = lnav_data.ld_exec_context;
     logfile_sub_source *lss = NULL;
+    text_sub_source *tc_tss = tc->get_sub_source();
     bookmarks<vis_line_t>::type &     bm  = tc->get_bookmarks();
 
     if (tc->handle_key(ch)) {
@@ -927,9 +928,11 @@ void handle_paging_key(int ch)
                 );
 
                 tc->reload_data();
-            } else {
+            } else if (tc_tss != nullptr && tc_tss->tss_supports_filtering) {
                 lnav_data.ld_mode = LNM_FILTER;
                 lnav_data.ld_filter_view.reload_data();
+            } else {
+                alerter::singleton().chime();
             }
             break;
 

src/logfile_sub_source.cc

@@ -106,6 +106,7 @@ logfile_sub_source::logfile_sub_source()
       lss_longest_line(0),
       lss_meta_grepper(*this)
 {
+    this->tss_supports_filtering = true;
     this->clear_line_size_cache();
     this->clear_min_max_log_times();
 }

src/textfile_sub_source.hh

@@ -40,7 +40,9 @@ class textfile_sub_source : public text_sub_source {
 public:
     typedef std::list<std::shared_ptr<logfile>>::iterator file_iterator;
 
-    textfile_sub_source() { };
+    textfile_sub_source() {
+        this->tss_supports_filtering = true;
+    };
 
     bool empty() const {
         return this->tss_files.empty();

src/textview_curses.hh

@@ -455,6 +455,7 @@ public:
         return nonstd::nullopt;
     }
 
+    bool tss_supports_filtering{false};
 protected:
     textview_curses *tss_view;
     filter_stack tss_filters;

src/view_helpers.cc

@@ -215,6 +215,19 @@ void layout_views()
     bool doc_side_by_side = width > (90 + 60);
     bool preview_status_open = !lnav_data.ld_preview_status_source
                                          .get_description().empty();
+    bool filter_status_open = false;
+
+    lnav_data.ld_view_stack.top() | [&] (auto tc) {
+        text_sub_source *tss = tc->get_sub_source();
+
+        if (tss == nullptr) {
+            return;
+        }
+
+        if (tss->tss_supports_filtering) {
+            filter_status_open = true;
+        }
+    };
 
     if (doc_side_by_side) {
         doc_height = std::max(
@@ -255,9 +268,12 @@ void layout_views()
         + lnav_data.ld_rl_view->get_height();
 
     for (auto &tc : lnav_data.ld_views) {
-        tc.set_height(vis_line_t(-(bottom_height + filter_height)));
+        tc.set_height(vis_line_t(-(bottom_height
+                                   + (filter_status_open ? 1 : 0)
+                                   + filter_height)));
     }
     lnav_data.ld_status[LNS_TOP].set_enabled(!filters_open);
+    lnav_data.ld_status[LNS_FILTER].set_visible(filter_status_open);
     lnav_data.ld_status[LNS_FILTER].set_enabled(filters_open);
     lnav_data.ld_status[LNS_FILTER].set_top(-(bottom_height + filter_height + 1));
     lnav_data.ld_status[LNS_BOTTOM].set_top(-(match_height + 2));

test/expected_help.txt

@@ -143,8 +143,17 @@ Above and below the main body are status lines that display:
   * the current view;
   * the line number for the top line in the display;
   * the current search hit and the total number of hits;
+
+If the view supports filtering, there will be a status line showing the
+following:
+
+  * the number of enabled filters and the total number of filters;
   * the number of lines not displayed because of filtering.
 
+To edit the filters, you can press TAB to change the focus from the main
+view to the filter editor.  The editor allows you to create, enable/disable,
+and delete filters easily.
+
 Finally, the last line on the display is where you can enter search
 patterns and execute internal commands, such as converting a
 unix-timestamp into a human-readable date.  The command-line is