From 3f8e61a4e41bf9d921f2189e76bf4c31ea97b429 Mon Sep 17 00:00:00 2001
From: Olivier Roques <olivier@oroques.dev>
Date: Fri, 25 Dec 2020 21:54:44 +0100
Subject: [PATCH] Refactor

---
 lua/hardline.lua                  | 81 +++++++++++++++++++++----------
 lua/hardline/common.lua           | 38 +++++++++------
 lua/hardline/parts/filename.lua   | 21 +++++++-
 lua/hardline/parts/filetype.lua   |  6 +--
 lua/hardline/parts/git.lua        | 16 +++---
 lua/hardline/parts/line.lua       |  6 +--
 lua/hardline/parts/lsp.lua        |  2 +-
 lua/hardline/parts/mode.lua       | 12 +++--
 lua/hardline/parts/whitespace.lua | 20 ++++----
 lua/hardline/parts/wordcount.lua  | 16 +++---
 10 files changed, 138 insertions(+), 80 deletions(-)

diff --git a/lua/hardline.lua b/lua/hardline.lua
index 3bde6ef..94466f6 100644
--- a/lua/hardline.lua
+++ b/lua/hardline.lua
@@ -27,45 +27,76 @@ M.options = {
 }
 
 -------------------- STATUSLINE ----------------------------
-local function get_state(class)
-  if class == 'mode' and common.is_active() then
-    local mode = common.modes[vim.fn.mode()]
-    if not mode then return common.modes['?'].color end
-    return mode.color
+local function color_sections(sections)
+  local function map(section)
+    if type(section) ~= 'table' then return section end
+    if section.class == 'none' then return section.item end
+    local state = common.get_state(section.class)
+    local hlgroup = string.format('Hardline_%s_%s', section.class, state)
+    if fn.hlexists(hlgroup) == 0 then return section.item end
+    return string.format('%%#%s#%s%%*', hlgroup, section.item)
   end
-  return common.is_active() and 'active' or 'inactive'
+  return vim.tbl_map(map, sections)
 end
 
-local function color_section(section)
-  if type(section) ~= 'table' then return section end
-  if not section.class or section.class == 'none' then return section.item end
-  local state = get_state(section.class)
-  local hlgroup = string.format('Hardline_%s_%s', section.class, state)
-  if fn.hlexists(hlgroup) == 0 then return section.item end
-  return string.format('%%#%s#%s%%*', hlgroup, section.item)
+local function aggregate_sections(sections)
+  local aggregated, piv = {}, 1
+  while piv <= #sections do
+    if type(sections[piv]) == 'table' then
+      local items = {}
+      for j = piv, #sections + 1 do
+        if j == #sections + 1 or sections[j].class ~= sections[piv].class then
+          table.insert(aggregated, {
+            class = sections[piv].class,
+            item = string.format(' %s ', table.concat(items, ' '))
+          })
+          piv = j
+          break
+        end
+        table.insert(items, sections[j].item)
+      end
+    else
+      table.insert(aggregated, sections[piv])
+      piv = piv + 1
+    end
+  end
+  return aggregated
 end
 
-local function update_section(section)
-  if type(section) == 'string' then
-    return section
-  elseif type(section) == 'function' then
-    return section()
-  elseif type(section) == 'table' then
-    return {class = section.class, item = update_section(section.item)}
+local function remove_empty_sections(sections)
+  local function filter(section)
+    if type(section) == 'table' then return filter(section.item) end
+    return section ~= ''
   end
-  common.echo('WarningMsg', 'Invalid section.')
-  return ''
+  return vim.tbl_filter(filter, sections)
+end
+
+local function reload_sections(sections)
+  local function map(section)
+    if type(section) == 'string' then
+      return section
+    elseif type(section) == 'function' then
+      return section()
+    elseif type(section) == 'table' then
+      return {class = section.class or 'none', item = map(section.item)}
+    end
+    common.echo('WarningMsg', 'Invalid section.')
+    return ''
+  end
+  return vim.tbl_map(map, sections)
 end
 
 function M.update()
-  local cache
+  local cache = M.options.sections
   if common.is_active() then
-    cache = vim.tbl_map(update_section, M.options.sections)
+    cache = reload_sections(cache)
+    cache = remove_empty_sections(cache)
+    cache = aggregate_sections(cache)
     api.nvim_win_set_var(g.statusline_winid, 'hardline_cache', cache)
   else
     cache = api.nvim_win_get_var(g.statusline_winid, 'hardline_cache')
   end
-  return table.concat(vim.tbl_map(color_section, cache))
+  return table.concat(color_sections(cache))
 end
 
 -------------------- SETUP -----------------------------
diff --git a/lua/hardline/common.lua b/lua/hardline/common.lua
index 545042c..f57b2b7 100644
--- a/lua/hardline/common.lua
+++ b/lua/hardline/common.lua
@@ -1,20 +1,20 @@
 local cmd, fn, vim = vim.cmd, vim.fn, vim
 local g = vim.g
-local M = {
-  modes = {
-    ['?'] = {text = '???', color = 'inactive'},
-    ['n'] = {text = 'NORMAL', color = 'normal'},
-    ['c'] = {text = 'COMMAND', color = 'normal'},
-    ['i'] = {text = 'INSERT', color = 'insert'},
-    ['R'] = {text = 'REPLACE', color = 'replace'},
-    ['v'] = {text = 'VISUAL', color = 'visual'},
-    ['V'] = {text = 'V-LINE', color = 'visual'},
-    [''] = {text = 'V-BLOCK', color = 'visual'},
-    ['s'] = {text = 'SELECT', color = 'visual'},
-    ['S'] = {text = 'S-LINE', color = 'visual'},
-    [''] = {text = 'S-BLOCK', color = 'visual'},
-    ['t'] = {text = 'TERMINAL', color = 'normal'},
-  }
+local M = {}
+
+M.modes = {
+  ['?'] = {text = '???', state = 'inactive'},
+  ['n'] = {text = 'NORMAL', state = 'normal'},
+  ['i'] = {text = 'INSERT', state = 'insert'},
+  ['R'] = {text = 'REPLACE', state = 'replace'},
+  ['v'] = {text = 'VISUAL', state = 'visual'},
+  ['V'] = {text = 'V-LINE', state = 'visual'},
+  [''] = {text = 'V-BLOCK', state = 'visual'},
+  ['c'] = {text = 'COMMAND', state = 'normal'},
+  ['s'] = {text = 'SELECT', state = 'visual'},
+  ['S'] = {text = 'S-LINE', state = 'visual'},
+  [''] = {text = 'S-BLOCK', state = 'visual'},
+  ['t'] = {text = 'TERMINAL', state = 'normal'},
 }
 
 function M.echo(hlgroup, msg)
@@ -27,4 +27,12 @@ function M.is_active()
   return g.statusline_winid == fn.win_getid()
 end
 
+function M.get_state(class)
+  if class == 'mode' and M.is_active() then
+    local mode = M.modes[fn.mode()] or M.modes['?']
+    return mode.state
+  end
+  return M.is_active() and 'active' or 'inactive'
+end
+
 return M
diff --git a/lua/hardline/parts/filename.lua b/lua/hardline/parts/filename.lua
index 5d4d671..eaa37e4 100644
--- a/lua/hardline/parts/filename.lua
+++ b/lua/hardline/parts/filename.lua
@@ -1,7 +1,26 @@
 local fn = vim.fn
+local bo = vim.bo
+
+local function get_name()
+  return fn.expand('%:~:.')
+end
+
+local function get_readonly()
+  if not bo.readonly then return '' end
+  return '[RO]'
+end
+
+local function get_modified()
+  if bo.modified then return '[+]' end
+  if not bo.modifiable then return '[-]' end
+  return ''
+end
 
 local function get_item()
-  return table.concat({' ', fn.expand('%:~:.'), ' %r%m '})
+  local name, readonly, modified = get_name(), get_readonly(), get_modified()
+  if readonly ~= '' then readonly = ' ' .. readonly end
+  if modified ~= '' then modified = ' ' .. modified end
+  return table.concat({name, readonly, modified})
 end
 
 return {
diff --git a/lua/hardline/parts/filetype.lua b/lua/hardline/parts/filetype.lua
index 9ada887..f35bd99 100644
--- a/lua/hardline/parts/filetype.lua
+++ b/lua/hardline/parts/filetype.lua
@@ -1,11 +1,7 @@
 local bo = vim.bo
 
-local function get_filetype()
-  return string.format('%s', bo.filetype)
-end
-
 local function get_item()
-  return table.concat({' ', get_filetype(), ' '})
+  return bo.filetype
 end
 
 return {
diff --git a/lua/hardline/parts/git.lua b/lua/hardline/parts/git.lua
index 62abcfa..fe5beb1 100644
--- a/lua/hardline/parts/git.lua
+++ b/lua/hardline/parts/git.lua
@@ -5,20 +5,22 @@ local function get_hunks()
   if not g.loaded_gitgutter then return '' end
   local summary = fn.GitGutterGetHunkSummary()
   return table.concat({
-    string.format('+%d', summary[1]), ' ',
-    string.format('~%d', summary[2]), ' ',
-    string.format('-%d', summary[3]), ' ',
-  })
+    string.format('+%d', summary[1]),
+    string.format('~%d', summary[2]),
+    string.format('-%d', summary[3]),
+  }, ' ')
 end
 
 local function get_branch()
   if not g.loaded_gitgutter then return '' end
-  return string.format('(%s)', fn.FugitiveHead())
+  local branch = fn.FugitiveHead()
+  return branch ~= '' and string.format('(%s)', branch) or ''
 end
 
 local function get_item()
-  local item = table.concat({' ', get_hunks(), get_branch(), ' '})
-  return item == '  ' and '' or item
+  local hunks, branch = get_hunks(), get_branch()
+  if branch == '' then return '' end
+  return table.concat({hunks, ' ' .. branch})
 end
 
 return {
diff --git a/lua/hardline/parts/line.lua b/lua/hardline/parts/line.lua
index 96b7eb3..0632466 100644
--- a/lua/hardline/parts/line.lua
+++ b/lua/hardline/parts/line.lua
@@ -9,18 +9,18 @@ end
 local function get_column()
   local nb_columns = fn.col('$') - 1
   local column = fn.col('.')
-  return string.format(' %2d/%2d', column, nb_columns)
+  return string.format('%2d/%2d', column, nb_columns)
 end
 
 local function get_percent()
   local nb_lines = fn.line('$')
   local line = fn.line('.')
   local percent = math.floor(line * 100 / nb_lines)
-  return string.format(' %3d%%%%', percent)
+  return string.format('%3d%%%%', percent)
 end
 
 local function get_item()
-  return table.concat({' ', get_line(), get_column(), get_percent(), ' '})
+  return table.concat({get_line(), get_column(), get_percent()}, ' ')
 end
 
 return {
diff --git a/lua/hardline/parts/lsp.lua b/lua/hardline/parts/lsp.lua
index 6cb87b4..797d490 100644
--- a/lua/hardline/parts/lsp.lua
+++ b/lua/hardline/parts/lsp.lua
@@ -4,7 +4,7 @@ local function get_diagnostic(prefix, severity)
   if vim.tbl_isempty(lsp.buf_get_clients(0)) then return '' end
   local count = lsp.diagnostic.get_count(0, severity)
   if count < 1 then return '' end
-  return table.concat({' ', string.format('%s:%d', prefix, count), ' '})
+  return string.format('%s:%d', prefix, count)
 end
 
 local function get_error()
diff --git a/lua/hardline/parts/mode.lua b/lua/hardline/parts/mode.lua
index 12c9080..8248ccb 100644
--- a/lua/hardline/parts/mode.lua
+++ b/lua/hardline/parts/mode.lua
@@ -3,21 +3,25 @@ local o, bo, wo = vim.o, vim.bo, vim.wo
 local common = require('hardline.common')
 
 local function get_mode()
-  return common.modes[fn.mode()].text
+  local mode = common.modes[fn.mode()] or common.modes['?']
+  return mode.text
 end
 
 local function get_paste()
   if not o.paste then return '' end
-  return ' PASTE'
+  return 'PASTE'
 end
 
 local function get_spell()
   if not wo.spell then return '' end
-  return string.format(' SPELL[%s]', string.upper(bo.spelllang))
+  return string.format('SPELL[%s]', string.upper(bo.spelllang))
 end
 
 local function get_item()
-  return table.concat({' ', get_mode(), get_paste(), get_spell(), ' ' })
+  local mode, paste, spell = get_mode(), get_paste(), get_spell()
+  if paste ~= '' then paste = ' ' .. paste end
+  if spell ~= '' then spell = ' ' .. spell end
+  return table.concat({mode, paste, spell})
 end
 
 return {
diff --git a/lua/hardline/parts/whitespace.lua b/lua/hardline/parts/whitespace.lua
index 1b2f812..be44242 100644
--- a/lua/hardline/parts/whitespace.lua
+++ b/lua/hardline/parts/whitespace.lua
@@ -1,5 +1,6 @@
 local cmd, fn, vim = vim.cmd, vim.fn, vim
 local b, bo = vim.b, vim.bo
+
 local enabled = false
 local cache = ''
 local options = {
@@ -18,14 +19,14 @@ local function check_trailing()
   return search('trailing', [[\s$]])
 end
 
-local function check_mixed_indent()
+local function check_mix_indent()
   local tst = [[(^\t* +\t\s*\S)]]
   local tls = string.format([[(^\t+ {%d,}\S)]], bo.tabstop)
   local pattern = string.format([[\v%s|%s]], tst, tls)
   return search('mix-indent', pattern)
 end
 
-local function check_mixed_indent_file()
+local function check_mix_indent_file()
   local head_spc = [[\v(^ +)]]
   if vim.tbl_contains(options.c_langs, bo.filetype) then
     head_spc = [[\v(^ +\*@!)]]
@@ -51,22 +52,19 @@ local function get_item()
     cmd 'augroup hardline_whitespace'
     cmd 'autocmd!'
     cmd 'autocmd CursorHold,BufWritePost * unlet! b:hardline_whitespace'
-    cmd 'augroup end'
+    cmd 'augroup END'
     enabled = true
   end
   if bo.readonly or not bo.modifiable then return '' end
   if fn.line('$') > options.max_lines then return '' end
-  if fn.exists('b:hardline_whitespace') ~= 0 then return cache end
-  b.hardline_whitespace = 1
-  local item = table.concat({
-    ' ',
+  if b.hardline_whitespace then return cache end
+  b.hardline_whitespace = true
+  cache = table.concat({
     check_trailing(),
-    check_mixed_indent(),
-    check_mixed_indent_file(),
+    check_mix_indent(),
+    check_mix_indent_file(),
     check_conflict(),
-    ' ',
   })
-  cache = item == '  ' and '' or item
   return cache
 end
 
diff --git a/lua/hardline/parts/wordcount.lua b/lua/hardline/parts/wordcount.lua
index 7493fac..6b4260e 100644
--- a/lua/hardline/parts/wordcount.lua
+++ b/lua/hardline/parts/wordcount.lua
@@ -1,5 +1,7 @@
 local cmd, fn, vim = vim.cmd, vim.fn, vim
 local b, bo = vim.b, vim.bo
+local common = require('hardline.common')
+
 local enabled = false
 local cache = ''
 local options = {
@@ -19,7 +21,8 @@ local options = {
 }
 
 local function in_visual()
-  return vim.tbl_contains({'v', 'V', '', 's', 'S', ''}, fn.mode())
+  local mode = common.modes[fn.mode()] or common.modes['?']
+  return mode.state == 'visual'
 end
 
 local function get_wordcount()
@@ -33,17 +36,14 @@ local function get_item()
     cmd 'augroup hardline_wordcount'
     cmd 'autocmd!'
     cmd 'autocmd CursorHold,BufWritePost * unlet! b:hardline_wordcount'
-    cmd 'augroup end'
+    cmd 'augroup END'
     enabled = true
   end
   if not vim.tbl_contains(options.filetypes, bo.filetype) then return '' end
   if fn.line('$') > options.max_lines then return '' end
-  if fn.exists('b:hardline_wordcount') ~= 0 and not in_visual() then
-    return cache
-  end
-  b.hardline_wordcount = 1
-  local item = table.concat({' ', get_wordcount(), ' '})
-  cache = item == '  ' and '' or item
+  if b.hardline_wordcount and not in_visual() then return cache end
+  b.hardline_wordcount = true
+  cache = get_wordcount()
   return cache
 end