" Vim indent file
" Language: VisualBasic (ft=vb) / Basic (ft=basic) / SaxBasic (ft=vb)
" Author: Johannes Zellner <[email protected]>
" Last Change: Fri, 18 Jun 2004 07:22:42 CEST
" Small update 2010 Jul 28 by Maxim Kim

if exists("b:did_indent")
finish
endif
let b:did_indent = 1

setlocal autoindent
setlocal indentexpr=VbGetIndent(v:lnum)
setlocal indentkeys&
setlocal indentkeys+==~else,=~elseif,=~end,=~wend,=~case,=~next,=~select,=~loop,<:>

let b:undo_indent = "set ai< indentexpr< indentkeys<"

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

fun! VbGetIndent(lnum)
" labels and preprocessor get zero indent immediately
let this_line = getline(a:lnum)
let LABELS_OR_PREPROC = '^\s*\(\<\k\+\>:\s*$\|#.*\)'
if this_line =~? LABELS_OR_PREPROC
return 0
endif

" Find a non-blank line above the current line.
" Skip over labels and preprocessor directives.
let lnum = a:lnum
while lnum > 0
let lnum = prevnonblank(lnum - 1)
let previous_line = getline(lnum)
if previous_line !~? LABELS_OR_PREPROC
break
endif
endwhile

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

let ind = indent(lnum)

" Add
if previous_line =~? '^\s*\<\(begin\|\%(\%(private\|public\|friend\)\s\+\)\=\%(function\|sub\|property\)\|select\|case\|default\|if\|else\|elseif\|do\|for\|while\|enum\|with\)\>'
let ind = ind + &sw
endif

" Subtract
if this_line =~? '^\s*\<end\>\s\+\<select\>'
if previous_line !~? '^\s*\<select\>'
let ind = ind - 2 * &sw
else
" this case is for an empty 'select' -- 'end select'
" (w/o any case statements) like:
"
" select case readwrite
" end select
let ind = ind - &sw
endif
elseif this_line =~? '^\s*\<\(end\|else\|elseif\|until\|loop\|next\|wend\)\>'
let ind = ind - &sw
elseif this_line =~? '^\s*\<\(case\|default\)\>'
if previous_line !~? '^\s*\<select\>'
let ind = ind - &sw
endif
endif

return ind
endfun

" vim:sw=4