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/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