[overlay] try to fix issues between overlay and selection (related to #1088)

NEWS.md

@@ -1,3 +1,11 @@
+## lnav v0.11.2
+
+Features:
+* A "cursor" mode has been added to the main view that can
+  be toggled by pressing CTRL-X.  While in cursor mode, any
+  operations that would normally work on the "top" line now
+  operate on the selected line instead.
+
 ## lnav v0.11.1
 
 Features:

src/breadcrumb_curses.cc

@@ -175,7 +175,6 @@ breadcrumb_curses::reload_data()
     this->bc_match_view.set_needs_update();
     this->bc_match_view.set_selection(
         vis_line_t(selected_value.value_or(-1_vl)));
-    this->bc_match_view.scroll_selection_into_view();
     this->bc_match_view.reload_data();
     this->set_needs_update();
 }
@@ -257,7 +256,8 @@ breadcrumb_curses::handle_key(int ch)
                 this->focus();
                 this->reload_data();
                 if (this->bc_selected_crumb.value()
-                    < this->bc_focused_crumbs.size() - 1) {
+                    < this->bc_focused_crumbs.size() - 1)
+                {
                     this->bc_selected_crumb
                         = this->bc_selected_crumb.value() + 1;
                     retval = true;
@@ -333,13 +333,15 @@ breadcrumb_curses::perform_selection(
         = this->bc_focused_crumbs[this->bc_selected_crumb.value()];
     auto match_sel = this->bc_match_view.get_selection();
     if (match_sel >= 0
-        && match_sel < vis_line_t(this->bc_similar_values.size())) {
+        && match_sel < vis_line_t(this->bc_similar_values.size()))
+    {
         const auto& new_value = this->bc_similar_values[match_sel].p_key;
 
         switch (behavior) {
             case perform_behavior_t::if_different:
                 if (breadcrumb::crumb::key_t{new_value}
-                    == selected_crumb_ref.c_key) {
+                    == selected_crumb_ref.c_key)
+                {
                     return;
                 }
                 break;
@@ -418,7 +420,8 @@ breadcrumb_curses::search_overlay_source::list_value_for_overlay(
                     size_t index;
 
                     if (sscanf(parent->bc_current_search.c_str(), "%zu", &index)
-                        == 1) {
+                        == 1)
+                    {
                         if (index < 0
                             || (index
                                 >= (sel_opt

src/filter_sub_source.cc

@@ -646,7 +646,6 @@ filter_sub_source::rl_display_matches(readline_curses* rc)
     this->fss_match_view.set_x(rc->get_left() + rc->get_match_start());
     this->fss_match_view.set_width(width + 3);
     this->fss_match_view.set_needs_update();
-    this->fss_match_view.scroll_selection_into_view();
     this->fss_match_view.reload_data();
 }
 

src/listview_curses.cc

@@ -190,16 +190,36 @@ listview_curses::do_update()
         return;
     }
 
-    if (this->vc_needs_update) {
-        view_colors& vc = view_colors::singleton();
-        vis_line_t height, row, start_row;
+    vis_line_t height;
+    unsigned long width;
+
+    this->get_dimensions(height, width);
+
+    if (this->lv_selectable) {
+        if (this->lv_selection < 0_vl) {
+            this->set_top(0_vl);
+        } else if (this->lv_selection
+                   >= (this->lv_top + height - this->lv_tail_space - 1_vl))
+        {
+            this->set_top(
+                this->lv_selection - height + 1_vl + this->lv_tail_space, true);
+        } else if (this->lv_selection < this->lv_top) {
+            this->set_top(this->lv_selection, true);
+        }
+    }
+
+    while (this->vc_needs_update) {
+        auto& vc = view_colors::singleton();
+        vis_line_t row;
         attr_line_t overlay_line;
         struct line_range lr;
-        unsigned long width, wrap_width;
+        unsigned long wrap_width;
         int y = this->lv_y, bottom;
         auto role_attrs = vc.attrs_for_role(this->vc_default_role);
 
-        this->get_dimensions(height, width);
+        if (height <= 0) {
+            return;
+        }
 
         if (this->vc_width > 0) {
             width = std::min((unsigned long) this->vc_width, width);
@@ -211,20 +231,19 @@ listview_curses::do_update()
         }
 
         size_t row_count = this->get_inner_height();
+        size_t blank_rows = 0;
         row = this->lv_top;
-        start_row = row;
         bottom = y + height;
         std::vector<attr_line_t> rows(
             std::min((size_t) height, row_count - (int) this->lv_top));
         this->lv_source->listview_value_for_rows(*this, row, rows);
-        vis_line_t selected_in_view = this->get_selection() - this->get_top();
         while (y < bottom) {
             lr.lr_start = this->lv_left;
             lr.lr_end = this->lv_left + wrap_width;
             if (this->lv_overlay_source != nullptr
                 && this->lv_overlay_source->list_value_for_overlay(
                     *this,
-                    y - selected_in_view - this->lv_y,
+                    y - this->lv_y,
                     bottom - this->lv_y,
                     row,
                     overlay_line))
@@ -263,9 +282,18 @@ listview_curses::do_update()
                           nullptr);
                 mvwhline(this->lv_window, y, this->lv_x, ' ', width);
                 ++y;
+                blank_rows += 1;
             }
         }
 
+        if (this->lv_selectable && this->lv_selection >= 0
+            && (row > this->lv_tail_space) && (blank_rows < this->lv_tail_space)
+            && ((row - this->lv_tail_space) < this->lv_selection))
+        {
+            this->shift_top(this->lv_selection - row + this->lv_tail_space);
+            continue;
+        }
+
         if (this->lv_show_scrollbar) {
             double progress = 1.0;
             double coverage = 1.0;
@@ -367,7 +395,6 @@ listview_curses::shift_selection(int offset)
 
     if (new_selection >= 0_vl && new_selection < this->get_inner_height()) {
         this->set_selection(new_selection);
-        this->scroll_selection_into_view();
     }
 }
 
@@ -563,28 +590,6 @@ listview_curses::rows_available(vis_line_t line,
     return retval;
 }
 
-void
-listview_curses::scroll_selection_into_view()
-{
-    unsigned long width;
-    vis_line_t height;
-
-    this->get_dimensions(height, width);
-    if (height <= 0) {
-        return;
-    }
-    if (this->lv_selection < 0_vl) {
-        this->set_top(0_vl);
-    } else if (this->lv_selection
-               >= (this->lv_top + height - this->lv_tail_space - 1_vl))
-    {
-        this->set_top(this->lv_selection - height + 1_vl + this->lv_tail_space,
-                      true);
-    } else if (this->lv_selection < this->lv_top) {
-        this->set_top(this->lv_selection, true);
-    }
-}
-
 void
 listview_curses::set_selection(vis_line_t sel)
 {
@@ -623,7 +628,6 @@ listview_curses::set_selection(vis_line_t sel)
             }
             if (found) {
                 this->lv_selection = sel;
-                this->scroll_selection_into_view();
                 this->lv_source->listview_selection_changed(*this);
                 this->set_needs_update();
                 this->invoke_scroll();

src/listview_curses.hh

@@ -207,8 +207,6 @@ public:
 
     void set_selection(vis_line_t sel);
 
-    void scroll_selection_into_view();
-
     void shift_selection(int offset);
 
     vis_line_t get_selection() const