feat: Proper floating window for keymap help and OutlineStatus

No more obnoxious '}' on the cmdline when pressing `?`!

scope:
- More type hints
- Added class Float for creating floating windows with size that fit the
  content and position centered on the screen
- show_help action for outline window (key `?`) now uses a floating
  window
- :OutlineStatus now provides better information, and shows content in a
  floating window.

future:
- Floating window option configuration

lua/outline/config.lua

@@ -261,11 +261,6 @@ function M.get_providers()
   return M.providers
 end
 
-function M.show_help()
-  print('Current keymaps:')
-  print(vim.inspect(M.o.keymaps))
-end
-
 ---Check for inconsistent or mutually exclusive opts.
 -- Does not alter the opts. Might show messages.
 function M.check_config()

lua/outline/docs.lua

@@ -0,0 +1,129 @@
+local Float = require('outline.float')
+local cfg = require('outline.config')
+local providers = require('outline.providers')
+local utils = require('outline.utils')
+
+local M = {}
+
+function M.show_help()
+  local keyhint = 'Press q or <Esc> to close this window.'
+  local title = 'Current keymaps:'
+  local lines = { keyhint, '', title, '' }
+  ---@type outline.HL[]
+  local hl = { { line = 0, from = 0, to = #keyhint, name = 'Comment' } }
+  local left = {}
+  local right = {}
+  local max_left_width = 0
+  local indent = '    '
+  local key_hl = 'Special'
+
+  for action, keys in pairs(cfg.o.keymaps) do
+    if type(keys) == 'string' then
+      table.insert(left, keys)
+      table.insert(hl, {
+        line = #left + 3,
+        from = #indent,
+        to = #keys + #indent,
+        name = key_hl,
+      })
+    else
+      local i = #indent
+      table.insert(left, table.concat(keys, ' / '))
+      for _, key in ipairs(keys) do
+        table.insert(hl, {
+          line = #left + 3,
+          from = i,
+          to = #key + i,
+          name = key_hl,
+        })
+        i = i + #key + 3
+      end
+    end
+    if #left[#left] > max_left_width then
+      max_left_width = #left[#left]
+    end
+    table.insert(right, action)
+  end
+
+  for i, l in ipairs(left) do
+    local pad = string.rep(' ', max_left_width - #l + 2)
+    table.insert(lines, indent .. l .. pad .. right[i])
+  end
+
+  local f = Float:new()
+  f:open(lines, hl, 'Outline Help', 1)
+
+  utils.nmap(f.bufnr, { 'q', '<Esc>' }, function()
+    f:close()
+  end)
+end
+
+---Display outline window status in a floating window
+---@param ctx outline.StatusContext
+function M.show_status(ctx)
+  local keyhint = 'Press q or <Esc> to close this window.'
+  local lines = { keyhint, '' }
+  ---@type outline.HL[]
+  local hl = { { line = 0, from = 0, to = #keyhint, name = 'Comment' } }
+  local p = ctx.provider
+  local priority = cfg.o.providers.priority
+  local pref
+
+  if utils.table_has_content(priority) then
+    pref = 'Configured providers are: '
+    table.insert(lines, pref .. table.concat(priority, ', ') .. '.')
+    local i = #pref
+    for _, name in ipairs(priority) do
+      table.insert(hl, { line = #lines - 1, from = i, to = i + #name, name = 'Special' })
+      i = i + #name + 2
+    end
+  else
+    pref = 'config '
+    local content = 'providers.priority'
+    table.insert(lines, pref .. content .. ' is an empty list!')
+    table.insert(hl, { line = #lines - 1, from = #pref, to = #pref + #content, name = 'ErrorMsg' })
+  end
+
+  table.insert(lines, '')
+
+  if p ~= nil then
+    pref = 'Current provider: '
+    table.insert(lines, pref .. p.name)
+    table.insert(hl, { line = #lines - 1, from = #pref, to = -1, name = 'Special' })
+    if p.get_status then
+      table.insert(lines, 'Provider info:')
+      table.insert(lines, '')
+      local l = p.get_status()
+      local indent = '    '
+      for _, line in ipairs(vim.split(l, '\n', { plain = true, trimempty = false })) do
+        table.insert(lines, indent .. line)
+      end
+    end
+
+    table.insert(lines, '')
+
+    table.insert(
+      lines,
+      ('Outline window is %s.'):format((ctx.outline_open and 'open') or 'not open')
+    )
+
+    table.insert(lines, '')
+
+    if ctx.code_win_active then
+      table.insert(lines, 'Code window is active.')
+    else
+      table.insert(lines, 'Code window is not active!')
+      table.insert(lines, 'Try closing and reopening the outline.')
+    end
+  else
+    table.insert(lines, 'No providers.')
+  end
+
+  local f = Float:new()
+  f:open(lines, hl, 'Outline Status', 1)
+  utils.nmap(f.bufnr, { 'q', '<Esc>' }, function()
+    f:close()
+  end)
+end
+
+return M

lua/outline/float.lua

@@ -0,0 +1,89 @@
+-- local cfg = require('outline.config')
+
+local Float = {}
+
+---@class outline.Float
+---@field bufnr integer
+---@field winnr integer
+---@field ns integer
+
+function Float:new()
+  return setmetatable({ bufnr = nil, winnr = nil, ns = nil }, { __index = Float })
+end
+
+---@param lines string[]
+---@param hl outline.HL[]
+---@param title string
+---@param indent integer?
+function Float:open(lines, hl, title, indent)
+  indent = indent or 0
+
+  self.bufnr = vim.api.nvim_create_buf(false, true)
+  vim.api.nvim_buf_set_option(self.bufnr, 'bufhidden', 'delete')
+
+  local maxwidth = 0
+  for _, l in ipairs(lines) do
+    if #l > maxwidth then
+      maxwidth = #l
+    end
+  end
+
+  local ui = vim.api.nvim_list_uis()[1]
+  local nvim_height, nvim_width = ui.height, ui.width
+
+  local padding_w = 3
+
+  local height, width = math.min(nvim_height, #lines + 1), maxwidth + 2 * padding_w
+  local row = math.floor((nvim_height - height) / 2)
+  local col = math.floor((nvim_width - width) / 2)
+
+  self.winnr = vim.api.nvim_open_win(self.bufnr, true, {
+    relative = 'editor',
+    width = width,
+    height = height,
+    row = row,
+    col = col,
+    border = 'rounded',
+    style = 'minimal',
+    title = title,
+    title_pos = 'center',
+  })
+
+  if indent > 0 then
+    local pad = string.rep(' ', indent)
+    for i = 1, #lines do
+      lines[i] = pad .. lines[i]
+    end
+  end
+
+  vim.api.nvim_win_set_option(self.winnr, 'winfixwidth', true)
+  vim.api.nvim_buf_set_lines(self.bufnr, 0, -1, false, lines)
+  vim.api.nvim_buf_set_option(self.bufnr, 'modifiable', false)
+  vim.api.nvim_buf_set_option(self.bufnr, 'ft', 'OutlineHelp')
+
+  if hl then
+    self.ns = vim.api.nvim_create_namespace('OutlineHelp')
+    for _, h in ipairs(hl) do
+      vim.api.nvim_buf_add_highlight(
+        self.bufnr,
+        self.ns,
+        h.name,
+        h.line,
+        h.from + indent,
+        (h.to ~= -1 and h.to + indent) or -1
+      )
+    end
+    vim.api.nvim_win_set_hl_ns(self.winnr, self.ns)
+  end
+end
+
+function Float:close()
+  if self.winnr then
+    vim.api.nvim_buf_clear_namespace(self.bufnr, self.ns, 0, -1)
+    vim.api.nvim_win_close(self.winnr, true)
+    self.winnr = nil
+    self.bufnr = nil
+  end
+end
+
+return Float

lua/outline/init.lua

@@ -72,24 +72,17 @@ end
 ---@param code_buf integer Must be valid
 local function setup_attached_buffer_autocmd(code_win, code_buf)
   local events = cfg.o.outline_items.auto_update_events
-  if
-    cfg.o.outline_items.highlight_hovered_item
-    or cfg.o.symbol_folding.auto_unfold_hover
-  then
+  if cfg.o.outline_items.highlight_hovered_item or cfg.o.symbol_folding.auto_unfold_hover then
     if M.state.autocmds[code_win] then
       vim.api.nvim_del_autocmd(M.state.autocmds[code_win])
       M.state.autocmds[code_win] = nil
     end
 
     if utils.str_or_nonempty_table(events.follow) then
-      M.state.autocmds[code_win] =
-        vim.api.nvim_create_autocmd(events.follow, {
+      M.state.autocmds[code_win] = vim.api.nvim_create_autocmd(events.follow, {
         buffer = code_buf,
         callback = function()
-            M._highlight_current_item(
-              code_win,
-              cfg.o.outline_items.auto_set_cursor
-            )
+          M._highlight_current_item(code_win, cfg.o.outline_items.auto_set_cursor)
         end,
       })
     end
@@ -398,7 +391,7 @@ local function setup_keymaps(bufnr)
   -- code actions
   map(cfg.o.keymaps.code_actions, require('outline.code_action').show_code_actions)
   -- show help
-  map(cfg.o.keymaps.show_help, require('outline.config').show_help)
+  map(cfg.o.keymaps.show_help, require('outline.docs').show_help)
   -- close outline
   map(cfg.o.keymaps.close, function()
     M.view:close()
@@ -611,37 +604,6 @@ function M.is_open()
   return M.view:is_open()
 end
 
----Display outline window status in the message area.
-function M.show_status()
-  -- TODO: Use a floating window instead
-  local p = _G._outline_current_provider
-  if not M.is_active() then
-    p = providers.find_provider()
-  end
-
-  if p ~= nil then
-    print('Current provider: ' .. p.name)
-    if p.get_status then
-      print(p.get_status())
-      print()
-    end
-
-    if M.view:is_open() then
-      print('Outline window is open.')
-    else
-      print('Outline window is not open.')
-    end
-
-    if require('outline.preview').has_code_win() then
-      print('Code window is active.')
-    else
-      print('Code window is either closed or invalid. Please close and reopen the outline window.')
-    end
-  else
-    print('No providers')
-  end
-end
-
 function M.is_active()
   local winid = vim.fn.win_getid()
   if M.view:is_open() and winid == M.view.winnr then
@@ -659,6 +621,29 @@ function M.has_provider()
   return providers.has_provider()
 end
 
+function M.show_status()
+  ---@type outline.StatusContext
+  local ctx = {}
+  local p = _G._outline_current_provider
+  if not M.is_active() then
+    p = providers.find_provider()
+  end
+
+  if p ~= nil then
+    ctx.provider = p
+    ctx.outline_open = false
+    if M.view and M.view:is_open() then
+      ctx.outline_open = true
+    end
+    ctx.code_win_active = false
+    if require('outline.preview').has_code_win() then
+      ctx.code_win_active = true
+    end
+  end
+
+  return require('outline.docs').show_status(ctx)
+end
+
 local function setup_commands()
   local cmd = function(n, c, o)
     vim.api.nvim_create_user_command('Outline' .. n, c, o)

lua/outline/providers/init.lua

@@ -3,8 +3,6 @@ local cfg = require('outline.config')
 local M = {}
 local import_prefix = 'outline/providers/'
 
-_G._outline_current_provider = nil
-
 function M.find_provider()
   if not M.providers then
     M.providers = vim.tbl_map(function(p)

lua/outline/types/outline.lua

@@ -60,6 +60,28 @@
 ---@field hovered boolean
 ---@field folded boolean
 
+-- PROVIDER
+
+---@class outline.Provider
+---@field should_use_provider fun(bufnr:integer):boolean
+---@field hover_info fun(bufnr:integer, params:table, on_info:function)
+---@field request_symbols fun(on_symbols:function, opts:table)
+---@field name string
+---@field get_status? fun():string
+
+-- HELP
+
+---@class outline.HL
+---@field line integer
+---@field from integer
+---@field to integer
+---@field name string
+
+---@class outline.StatusContext
+---@field provider outline.Provider?
+---@field outline_open boolean?
+---@field code_win_active boolean?
+
 -- API
 
 ---@class outline.OutlineOpts

lua/outline/view.lua

@@ -2,6 +2,10 @@ local cfg = require('outline.config')
 
 local View = {}
 
+---@class View
+---@field bufnr integer
+---@field winnr integer
+
 function View:new()
   return setmetatable({ bufnr = nil, winnr = nil }, { __index = View })
 end