statusline.vim

set statusline=%#identifier#
set statusline+=[%t]\ %{ReadOnly()}     "filename
set statusline+=%*

"Warn if not unix
set statusline+=%#warningmsg#
set statusline+=%{&ff!='unix'?'['.&ff.']':''}
set statusline+=%*

"Warn if not unix
set statusline+=%#warningmsg#
set statusline+=%{(&fenc!='utf-8'&&&fenc!='')?'['.&fenc.']':''}
set statusline+=%*

set statusline+=%h      "helpfile flag
set statusline+=%y      "filetype

"modified flag
set statusline+=%#identifier#
set statusline+=%m
set statusline+=%*

set statusline+=%{fugitive#statusline()}

"display a warning if &et is wrong, or we have mixed-indenting
set statusline+=%#error#
set statusline+=%{StatuslineTabWarning()}
set statusline+=%*

set statusline+=%{StatuslineTrailingSpaceWarning()}

set statusline+=%{StatuslineLongLineWarning()}

"display a warning if &paste is set
set statusline+=%#error#
set statusline+=%{&paste?'[paste]':''}
set statusline+=%*

set statusline+=%=      "left/right separator

set statusline+=%#Keyword#
set statusline+=%{tagbar#currenttag('%s','','f')}
set statusline+=%*

set statusline+=%-3(%{FileSize()}%) "FileSize

set statusline+=%{StatuslineCurrentHighlight()}\ \ "current highlight
set statusline+=%c,     "cursor column
set statusline+=%l/%L   "cursor line/total lines
set statusline+=\ %P    "percent through file
set laststatus=2

"recalculate the trailing whitespace warning when idle, and after saving
autocmd cursorhold,bufwritepost * unlet! b:statusline_trailing_space_warning

"return '[\s]' if trailing white space is detected
"return '' otherwise
function! StatuslineTrailingSpaceWarning()
    if !exists("b:statusline_trailing_space_warning")

        if !&modifiable
            let b:statusline_trailing_space_warning = ''
            return b:statusline_trailing_space_warning
        endif

        if search('\s\+$', 'nw') != 0
            let b:statusline_trailing_space_warning = '[\s]'
        else
            let b:statusline_trailing_space_warning = ''
        endif
    endif
    return b:statusline_trailing_space_warning
endfunction


"return the syntax highlight group under the cursor ''
function! StatuslineCurrentHighlight()
    let name = synIDattr(synID(line('.'),col('.'),1),'name')
    if name == ''
        return ''
    else
        return '[' . name . ']'
    endif
endfunction

"recalculate the tab warning flag when idle and after writing
autocmd cursorhold,bufwritepost * unlet! b:statusline_tab_warning

"return '[&et]' if &et is set wrong
"return '[mixed-indenting]' if spaces and tabs are used to indent
"return an empty string if everything is fine
function! StatuslineTabWarning()
    if !exists("b:statusline_tab_warning")
        let b:statusline_tab_warning = ''

        if !&modifiable
            return b:statusline_tab_warning
        endif

        let tabs = search('^\t', 'nw') != 0

        "find spaces that arent used as alignment in the first indent column
        let spaces = search('^ \{' . &ts . ',}[^\t]', 'nw') != 0

        if tabs && spaces
            let b:statusline_tab_warning =  '[mixed-indenting]'
        elseif (spaces && !&et) || (tabs && &et)
            let b:statusline_tab_warning = '[&et]'
        endif
    endif
    return b:statusline_tab_warning
endfunction

"recalculate the long line warning when idle and after saving
autocmd cursorhold,bufwritepost * unlet! b:statusline_long_line_warning

"return a warning for "long lines" where "long" is either &textwidth or 80 (if
"no &textwidth is set)
"
"return '' if no long lines
"return '[#x,my,$z] if long lines are found, were x is the number of long
"lines, y is the median length of the long lines and z is the length of the
"longest line
function! StatuslineLongLineWarning()
    if !exists("b:statusline_long_line_warning")

        if !&modifiable
            let b:statusline_long_line_warning = ''
            return b:statusline_long_line_warning
        endif

        let long_line_lens = s:LongLines()

        if len(long_line_lens) > 0
            let b:statusline_long_line_warning = "[" .
                        \ '#' . len(long_line_lens) . "," .
                        \ 'm' . s:Median(long_line_lens) . "," .
                        \ '$' . max(long_line_lens) . "]"
        else
            let b:statusline_long_line_warning = ""
        endif
    endif
    return b:statusline_long_line_warning
endfunction

"return a list containing the lengths of the long lines in this buffer
function! s:LongLines()
    let threshold = (&tw ? &tw : 80)
    let spaces = repeat(" ", &ts)
    let line_lens = map(getline(1,'$'), 'len(substitute(v:val, "\\t", spaces, "g"))')
    return filter(line_lens, 'v:val > threshold')
endfunction

"find the median of the given array of numbers
function! s:Median(nums)
    let nums = sort(a:nums)
    let l = len(nums)

    if l % 2 == 1
        let i = (l-1) / 2
        return nums[i]
    else
        return (nums[l/2] + nums[(l/2)-1]) / 2
    endif
endfunction

" Find out current buffer's size and output it.
function! FileSize()
  let bytes = getfsize(expand('%:p'))
  if (bytes >= 1024)
    let kbytes = bytes / 1024
  endif
  if (exists('kbytes') && kbytes >= 1000)
    let mbytes = kbytes / 1000
  endif

  if bytes <= 0
    return '0'
  endif

  if (exists('mbytes'))
    return mbytes . 'MB '
  elseif (exists('kbytes'))
    return kbytes . 'KB '
  else
    return bytes . 'B '
  endif
endfunction

function! ReadOnly()
  if &readonly || !&modifiable
    return ' '
  else
    return ''
endfunction