" Vim ftplugin file
" Language: Erlang
" Author: Oscar Hellström <[email protected]>
" Contributors: Ricardo Catalinas Jiménez <[email protected]>
" Eduardo Lopez (http://github.com/tapichu)
" License: Vim license
" Version: 2012/01/25

if exists('b:did_ftplugin')
finish
else
let b:did_ftplugin = 1
endif

if exists('s:did_function_definitions')
call s:SetErlangOptions()
finish
else
let s:did_function_definitions = 1
endif

let s:cpo_save = &cpo
set cpo&vim

if !exists('g:erlang_keywordprg')
let g:erlang_keywordprg = 'erl -man'
endif

if !exists('g:erlang_folding')
let g:erlang_folding = 0
endif

let s:erlang_fun_begin = '^\a\w*(.*$'
let s:erlang_fun_end = '^[^%]*\.\s*\(%.*\)\?$'

function s:SetErlangOptions()
if g:erlang_folding
setlocal foldmethod=expr
setlocal foldexpr=GetErlangFold(v:lnum)
setlocal foldtext=ErlangFoldText()
endif

setlocal comments=:%%%,:%%,:%
setlocal commentstring=%%s

setlocal formatoptions+=ro
let &l:keywordprg = g:erlang_keywordprg
endfunction

function GetErlangFold(lnum)
let lnum = a:lnum
let line = getline(lnum)

if line =~ s:erlang_fun_end
return '<1'
endif

if line =~ s:erlang_fun_begin && foldlevel(lnum - 1) == 1
return '1'
endif

if line =~ s:erlang_fun_begin
return '>1'
endif

return '='
endfunction

function ErlangFoldText()
let line = getline(v:foldstart)
let foldlen = v:foldend - v:foldstart + 1
let lines = ' ' . foldlen . ' lines: ' . substitute(line, "[\ \t]*", '', '')
if foldlen < 10
let lines = ' ' . lines
endif
let retval = '+' . v:folddashes . lines

return retval
endfunction

call s:SetErlangOptions()

let b:undo_ftplugin = "setlocal foldmethod< foldexpr< foldtext<"
\ . " comments< commentstring< formatoptions<"

let &cpo = s:cpo_save
unlet s:cpo_save