Improvements and new features to autocomplete plugin in preparation for LSP plugin. (#235)

data/plugins/autocomplete.lua

@@ -8,25 +8,65 @@ local keymap = require "core.keymap"
 local translate = require "core.doc.translate"
 local RootView = require "core.rootview"
 local DocView = require "core.docview"
+local Doc = require "core.doc"
 
-config.autocomplete_max_suggestions = 6
+-- Amount of characters that need to be written for autocomplete
+config.autocomplete_min_len = 1
+-- The max amount of visible items
+config.autocomplete_max_height = 6
+-- The max amount of scrollable items
+config.autocomplete_max_suggestions = 100
+-- Maximum amount of symbols to cache per document
+config.max_symbols = 2000
 
 local autocomplete = {}
-autocomplete.map = {}
 
+autocomplete.map = {}
+autocomplete.map_manually = {}
+autocomplete.on_close = nil
+
+-- Flag that indicates if the autocomplete box was manually triggered
+-- with the autocomplete.complete() function to prevent the suggestions
+-- from getting cluttered with arbitrary document symbols by using the
+-- autocomplete.map_manually table.
+local triggered_manually = false
 
 local mt = { __tostring = function(t) return t.text end }
 
-function autocomplete.add(t)
+function autocomplete.add(t, triggered_manually)
   local items = {}
   for text, info in pairs(t.items) do
+    if type(info) == "table" then
+      table.insert(
+        items,
+        setmetatable(
+          {
+            text = text,
+            info = info.info,
+            desc = info.desc,  -- Description shown on item selected
+            cb = info.cb,      -- A callback called once when item is selected
+            data = info.data   -- Optional data that can be used on cb
+          },
+          mt
+        )
+      )
+    else
       info = (type(info) == "string") and info
       table.insert(items, setmetatable({ text = text, info = info }, mt))
     end
-  autocomplete.map[t.name] =  { files = t.files or ".*", items = items }
   end
 
-local max_symbols = config.max_symbols or 2000
+  if not triggered_manually then
+    autocomplete.map[t.name] =  { files = t.files or ".*", items = items }
+  else
+    autocomplete.map_manually[t.name] =  { files = t.files or ".*", items = items }
+  end
+end
+
+--
+-- Thread that scans open document symbols and cache them
+--
+local max_symbols = config.max_symbols
 
 core.add_thread(function()
   local cache = setmetatable({}, { __mode = "k" })
@@ -109,16 +149,39 @@ local last_line, last_col
 local function reset_suggestions()
   suggestions_idx = 1
   suggestions = {}
+
+  triggered_manually = false
+
+  local doc = core.active_view.doc
+  if autocomplete.on_close then
+    autocomplete.on_close(doc, suggestions[suggestions_idx])
+    autocomplete.on_close = nil
+  end
 end
 
+local function in_table(value, table_array)
+  for i, element in pairs(table_array) do
+    if element == value then
+      return true
+    end
+  end
+
+  return false
+end
 
 local function update_suggestions()
   local doc = core.active_view.doc
   local filename = doc and doc.filename or ""
 
+  local map = autocomplete.map
+
+  if triggered_manually then
+    map = autocomplete.map_manually
+  end
+
   -- get all relevant suggestions for given filename
   local items = {}
-  for _, v in pairs(autocomplete.map) do
+  for _, v in pairs(map) do
     if common.match_pattern(filename, v.files) then
       for _, item in pairs(v.items) do
         table.insert(items, item)
@@ -138,7 +201,6 @@ local function update_suggestions()
   end
 end
 
-
 local function get_partial_symbol()
   local doc = core.active_view.doc
   local line2, col2 = doc:get_selection()
@@ -146,14 +208,12 @@ local function get_partial_symbol()
   return doc:get_text(line1, col1, line2, col2)
 end
 
-
 local function get_active_view()
   if getmetatable(core.active_view) == DocView then
     return core.active_view
   end
 end
 
-
 local function get_suggestions_rect(av)
   if #suggestions == 0 then
     return 0, 0, 0, 0
@@ -175,15 +235,67 @@ local function get_suggestions_rect(av)
     max_width = math.max(max_width, w)
   end
 
+  local ah = config.autocomplete_max_height
+
+  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
+    max_width = 150
+  end
+
   return
     x - style.padding.x,
     y - style.padding.y,
     max_width + style.padding.x * 2,
-    #suggestions * (th + style.padding.y) + style.padding.y
+    max_items * (th + style.padding.y) + style.padding.y
 end
 
+local function draw_description_box(text, av, sx, sy, sw, sh)
+  local width = 0
+
+  local lines = {}
+  for line in string.gmatch(text.."\n", "(.-)\n") do
+    width = math.max(width, style.font:get_width(line))
+    table.insert(lines, line)
+  end
+
+  local height = #lines * style.font:get_height()
+
+  -- draw background rect
+  renderer.draw_rect(
+    sx + sw + style.padding.x / 4,
+    sy,
+    width + style.padding.x * 2,
+    height + style.padding.y * 2,
+    style.background3
+  )
+
+  -- draw text
+  local lh = style.font:get_height()
+  local y = sy + style.padding.y
+  local x = sx + sw + style.padding.x / 4
+
+  for _, line in pairs(lines) do
+    common.draw_text(
+      style.font, style.text, line, "left", x + style.padding.x, y, width, lh
+    )
+    y = y + lh
+  end
+end
 
 local function draw_suggestions_box(av)
+  if #suggestions <= 0 then
+    return
+  end
+
+  local ah = config.autocomplete_max_height
+
   -- draw background rect
   local rx, ry, rw, rh = get_suggestions_rect(av)
   renderer.draw_rect(rx, ry, rw, rh, style.background3)
@@ -192,7 +304,14 @@ local function draw_suggestions_box(av)
   local font = av:get_font()
   local lh = font:get_height() + style.padding.y
   local y = ry + style.padding.y / 2
-  for i, s in ipairs(suggestions) do
+  local show_count = #suggestions <= ah and #suggestions or ah
+  local start_index = suggestions_idx > ah and (suggestions_idx-(ah-1)) or 1
+
+  for i=start_index, start_index+show_count-1, 1 do
+    if not suggestions[i] then
+      break
+    end
+    local s = suggestions[i]
     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)
     if s.info then
@@ -200,26 +319,55 @@ local function draw_suggestions_box(av)
       common.draw_text(style.font, color, s.info, "right", rx, y, rw - style.padding.x, lh)
     end
     y = y + lh
+    if suggestions_idx == i then
+      if s.cb then
+        s.cb(suggestions_idx, s)
+        s.cb = nil
+        s.data = nil
+      end
+      if s.desc and #s.desc > 0 then
+        draw_description_box(s.desc, av, rx, ry, rw, rh)
+      end
     end
   end
 
+  renderer.draw_rect(rx, y, rw, 2, style.caret)
+  renderer.draw_rect(rx, y+2, rw, lh, style.background)
+  common.draw_text(
+    style.font,
+    style.accent,
+    "Items",
+    "left",
+    rx + style.padding.x, y, rw, lh
+  )
+  common.draw_text(
+    style.font,
+    style.accent,
+    tostring(suggestions_idx) .. "/" .. tostring(#suggestions),
+    "right",
+    rx, y, rw - style.padding.x, lh
+  )
+end
 
--- patch event logic into RootView
+local function show_autocomplete()
-local on_text_input = RootView.on_text_input
-local update = RootView.update
-local draw = RootView.draw
-
-
-RootView.on_text_input = function(...)
-  on_text_input(...)
-
   local av = get_active_view()
   if av then
     -- update partial symbol and suggestions
     partial = get_partial_symbol()
-    if #partial >= 3 then
+
+    if #partial >= config.autocomplete_min_len or triggered_manually then
       update_suggestions()
+
+      if not triggered_manually then
         last_line, last_col = av.doc:get_selection()
+      else
+        local line, col = av.doc:get_selection()
+        local char = av.doc:get_char(line, col-1, line, col-1)
+
+        if char:match("%s") or (char:match("%p") and col ~= last_col) then
+          reset_suggestions()
+        end
+      end
     else
       reset_suggestions()
     end
@@ -233,6 +381,30 @@ RootView.on_text_input = function(...)
   end
 end
 
+--
+-- Patch event logic into RootView and Doc
+--
+local on_text_input = RootView.on_text_input
+local on_text_remove = Doc.remove
+local update = RootView.update
+local draw = RootView.draw
+
+RootView.on_text_input = function(...)
+  on_text_input(...)
+  show_autocomplete()
+end
+
+Doc.remove = function(self, line1, col1, line2, col2)
+  on_text_remove(self, line1, col1, line2, col2)
+
+  if triggered_manually and line1 == line2 then
+    if last_col >= col1 then
+      reset_suggestions()
+    else
+      show_autocomplete()
+    end
+  end
+end
 
 RootView.update = function(...)
   update(...)
@@ -241,12 +413,18 @@ RootView.update = function(...)
   if av then
     -- reset suggestions if caret was moved
     local line, col = av.doc:get_selection()
+
+    if not triggered_manually then
       if line ~= last_line or col ~= last_col then
         reset_suggestions()
       end
+    else
+      if line ~= last_line or col < last_col then
+        reset_suggestions()
+      end
+    end
   end
 end
-
 
 RootView.draw = function(...)
   draw(...)
@@ -258,12 +436,46 @@ RootView.draw = function(...)
   end
 end
 
+--
+-- Public functions
+--
+function autocomplete.open(on_close)
+  triggered_manually = true
 
+  if on_close then
+    autocomplete.on_close = on_close
+  end
+
+  local av = get_active_view()
+  last_line, last_col = av.doc:get_selection()
+  update_suggestions()
+end
+
+function autocomplete.close()
+  reset_suggestions()
+end
+
+function autocomplete.is_open()
+  return #suggestions > 0
+end
+
+function autocomplete.complete(completions, on_close)
+  reset_suggestions()
+
+  autocomplete.map_manually = {}
+  autocomplete.add(completions, true)
+
+  autocomplete.open(on_close)
+end
+
+
+--
+-- Commands
+--
 local function predicate()
   return get_active_view() and #suggestions > 0
 end
 
-
 command.add(predicate, {
   ["autocomplete:complete"] = function()
     local doc = core.active_view.doc
@@ -288,7 +500,9 @@ command.add(predicate, {
   end,
 })
 
-
+--
+-- Keymaps
+--
 keymap.add {
   ["tab"]    = "autocomplete:complete",
   ["up"]     = "autocomplete:previous",