Improve autocomplete suggestions box behavior (#1734)

* Improve `autocomplete` suggestions box sizing

This avoids that the box gets too big because of non-visible items, and makes it reactive to window sizing.

* Draw ellipsis when `autocomplete` entries aren't fully visible

data/plugins/autocomplete.lua

@@ -276,8 +276,10 @@ local function get_active_view()
   end
 end
 
+local last_max_width = 0
 local function get_suggestions_rect(av)
   if #suggestions == 0 then
+    last_max_width = 0
     return 0, 0, 0, 0
   end
 
@@ -287,38 +289,47 @@ local function get_suggestions_rect(av)
   local font = av:get_font()
   local th = font:get_height()
 
+  local ah = config.plugins.autocomplete.max_height
+
+  local max_items = math.min(ah, #suggestions)
+
+  local show_count = math.min(#suggestions, ah)
+  local start_index = math.max(suggestions_idx-(ah-1), 1)
+
   local max_width = 0
-  for _, s in ipairs(suggestions) do
+  for i = start_index, start_index + show_count - 1 do
+    local s = suggestions[i]
     local w = font:get_width(s.text)
     if s.info then
       w = w + style.font:get_width(s.info) + style.padding.x
     end
     max_width = math.max(max_width, w)
   end
+  max_width = math.max(last_max_width, max_width)
+  last_max_width = max_width
 
-  local ah = config.plugins.autocomplete.max_height
+  max_width = max_width + style.padding.x * 2
-
+  x = x - style.padding.x
-  local max_items = #suggestions
-  if max_items > ah then
-    max_items = ah
-  end
 
   -- additional line to display total items
   max_items = max_items + 1
 
-  if max_width < 150 then
+  if max_width > core.root_view.size.x then
-    max_width = 150
+    max_width = core.root_view.size.x
+  end
+  if max_width < 150 * SCALE then
+    max_width = 150 * SCALE
   end
 
   -- if portion not visiable to right, reposition to DocView right margin
-  if (x - av.position.x) + max_width > av.size.x then
+  if x + max_width > core.root_view.size.x then
-    x = (av.size.x + av.position.x) - max_width - (style.padding.x * 2)
+    x = (av.size.x + av.position.x) - max_width
   end
 
   return
-    x - style.padding.x,
+    x,
     y - style.padding.y,
-    max_width + style.padding.x * 2,
+    max_width,
     max_items * (th + style.padding.y) + style.padding.y
 end
 
@@ -454,8 +465,21 @@ local function draw_suggestions_box(av)
       break
     end
     local s = suggestions[i]
+
+    local info_size = s.info and (style.font:get_width(s.info) + style.padding.x) or style.padding.x
+
     local color = (i == suggestions_idx) and style.accent or style.text
-    common.draw_text(font, color, s.text, "left", rx + style.padding.x, y, rw, lh)
+    -- Push clip to avoid that the suggestion text gets drawn over suggestion type/icon
+    core.push_clip_rect(rx + style.padding.x, y, rw - info_size - style.padding.x, lh)
+    local x_adv = common.draw_text(font, color, s.text, "left", rx + style.padding.x, y, rw, lh)
+    core.pop_clip_rect()
+    -- If the text wasn't fully visible, draw an ellipsis
+    if x_adv > rx + rw - info_size then
+      local ellipsis_size = font:get_width("…")
+      local ell_x = rx + rw - info_size - ellipsis_size
+      renderer.draw_rect(ell_x, y, ellipsis_size, lh, style.background3)
+      common.draw_text(font, color, "…", "left", ell_x, y, ellipsis_size, lh)
+    end
     if s.info then
       color = (i == suggestions_idx) and style.text or style.dim
       common.draw_text(style.font, color, s.info, "right", rx, y, rw - style.padding.x, lh)