" Vim indent file
" Language: Autoconf configure.{ac,in} file
" Maintainer: Nikolai Weibull <[email protected]>
" Latest Revision: 2006-12-20
" TODO: how about nested [()]'s in one line
" what's wrong with '\\\@!'?

" Only load this indent file when no other was loaded.
if exists("b:did_indent")
finish
endif

runtime! indent/sh.vim " will set b:did_indent

setlocal indentexpr=GetConfigIndent()
setlocal indentkeys=!^F,o,O,=then,=do,=else,=elif,=esac,=fi,=fin,=fil,=done
setlocal nosmartindent

" Only define the function once.
if exists("*GetConfigIndent")
finish
endif

" get the offset (indent) of the end of the match of 'regexp' in 'line'
function s:GetOffsetOf(line, regexp)
let end = matchend(a:line, a:regexp)
let width = 0
let i = 0
while i < end
if a:line[i] != "\t"
let width = width + 1
else
let width = width + &ts - (width % &ts)
endif
let i = i + 1
endwhile
return width
endfunction

function GetConfigIndent()
" Find a non-blank line above the current line.
let lnum = prevnonblank(v:lnum - 1)

" Hit the start of the file, use zero indent.
if lnum == 0
return 0
endif

" where to put this
let ind = GetShIndent()
let line = getline(lnum)

" if previous line has unmatched, unescaped opening parentheses,
" indent to its position. TODO: not failsafe if multiple ('s
if line =~ '\\\@<!([^)]*$'
let ind = s:GetOffsetOf(line, '\\\@!(')
endif

" if previous line has unmatched opening bracket,
" indent to its position. TODO: same as above
if line =~ '\[[^]]*$'
let ind = s:GetOffsetOf(line, '\[')
endif

" if previous line had an unmatched closing parantheses,
" indent to the matching opening parantheses
if line =~ '[^(]\+\\\@<!)$'
call search(')', 'bW')
let lnum = searchpair('\\\@<!(', '', ')', 'bWn')
let ind = indent(lnum)
endif

" if previous line had an unmatched closing bracket,
" indent to the matching opening bracket
if line =~ '[^[]\+]$'
call search(']', 'bW')
let lnum = searchpair('\[', '', ']', 'bWn')
let ind = indent(lnum)
endif

return ind
endfunction