" PathSep returns the appropriate OS specific path separator.
function! go#util#PathSep()
  if go#util#IsWin()
    return '\'
  endif
  return '/'
endfunction

" PathListSep returns the appropriate OS specific path list separator.
function! go#util#PathListSep()
  if go#util#IsWin()
    return ";"
  endif
  return ":"
endfunction

" LineEnding returns the correct line ending, based on the current fileformat
function! go#util#LineEnding()
  if &fileformat == 'dos'
    return "\r\n"
  elseif &fileformat == 'mac'
    return "\r"
  endif

  return "\n"
endfunction

" Join joins any number of path elements into a single path, adding a
" Separator if necessary and returns the result
function! go#util#Join(...)
  return join(a:000, go#util#PathSep())
endfunction

" IsWin returns 1 if current OS is Windows or 0 otherwise
function! go#util#IsWin()
  let win = ['win16', 'win32', 'win64', 'win95']
  for w in win
    if (has(w))
      return 1
    endif
  endfor

  return 0
endfunction

function! go#util#GOARCH()
  return substitute(go#util#System('go env GOARCH'), '\n', '', 'g')
endfunction

function! go#util#GOOS()
  return substitute(go#util#System('go env GOOS'), '\n', '', 'g')
endfunction

function! go#util#GOROOT()
  return substitute(go#util#System('go env GOROOT'), '\n', '', 'g')
endfunction

function! go#util#GOPATH()
  return substitute(go#util#System('go env GOPATH'), '\n', '', 'g')
endfunction

function! go#util#OSARCH()
  return go#util#GOOS() . '_' . go#util#GOARCH()
endfunction


"Check if has vimproc
function! s:has_vimproc()
  if !exists('g:go#use_vimproc')
    if go#util#IsWin()
      try
        call vimproc#version()
        let exists_vimproc = 1
      catch
        let exists_vimproc = 0
      endtry
    else
      let exists_vimproc = 0
    endif

    let g:go#use_vimproc = exists_vimproc
  endif

  return g:go#use_vimproc
endfunction

if s:has_vimproc()
  let s:vim_system = get(g:, 'gocomplete#system_function', 'vimproc#system2')
  let s:vim_shell_error = get(g:, 'gocomplete#shell_error_function', 'vimproc#get_last_status')
else
  let s:vim_system = get(g:, 'gocomplete#system_function', 'system')
  let s:vim_shell_error = ''
endif

function! go#util#System(str, ...)
  return call(s:vim_system, [a:str] + a:000)
endfunction

function! go#util#ShellError()
  if empty(s:vim_shell_error)
    return v:shell_error
  endif
  return call(s:vim_shell_error, [])
endfunction


" StripPath strips the path's last character if it's a path separator.
" example: '/foo/bar/'  -> '/foo/bar'
function! go#util#StripPathSep(path)
  let last_char = strlen(a:path) - 1
  if a:path[last_char] == go#util#PathSep()
    return strpart(a:path, 0, last_char)
  endif

  return a:path
endfunction

" StripTrailingSlash strips the trailing slash from the given path list.
" example: ['/foo/bar/']  -> ['/foo/bar']
function! go#util#StripTrailingSlash(paths)
  return map(copy(a:paths), 'go#util#StripPathSep(v:val)')
endfunction

" Shelljoin returns a shell-safe string representation of arglist. The
" {special} argument of shellescape() may optionally be passed.
function! go#util#Shelljoin(arglist, ...)
  try
    let ssl_save = &shellslash
    set noshellslash
    if a:0
      return join(map(copy(a:arglist), 'shellescape(v:val, ' . a:1 . ')'), ' ')
    endif

        return join(map(copy(a:arglist), 'shellescape(v:val)'), ' ')
    finally
        let &shellslash = ssl_save
    endtry
endfunction

fu! go#util#Shellescape(arg)
    if s:has_vimproc()
        return vimproc#shellescape(a:arg)
    endif
    try
        let ssl_save = &shellslash
        set noshellslash
        return shellescape(a:arg)
    finally
        let &shellslash = ssl_save
    endtry
endf

" Shelllist returns a shell-safe representation of the items in the given
" arglist. The {special} argument of shellescape() may optionally be passed.
function! go#util#Shelllist(arglist, ...)
    try
        let ssl_save = &shellslash
        set noshellslash
        if a:0
            return map(copy(a:arglist), 'shellescape(v:val, ' . a:1 . ')')
        endif
        return map(copy(a:arglist), 'shellescape(v:val)')
    finally
        let &shellslash = ssl_save
    endtry
endfunction

" Returns the byte offset for line and column
function! go#util#Offset(line, col)
    if &encoding != 'utf-8'
        let sep = go#util#LineEnding()
        let buf = a:line == 1 ? '' : (join(getline(1, a:line-1), sep) . sep)
        let buf .= a:col == 1 ? '' : getline('.')[:a:col-2]
        return len(iconv(buf, &encoding, 'utf-8'))
    endif
    return line2byte(a:line) + (a:col-2)
endfunction
"
" Returns the byte offset for the cursor
function! go#util#OffsetCursor()
    return go#util#Offset(line('.'), col('.'))
endfunction

" Windo is like the built-in :windo, only it returns to the window the command
" was issued from
function! go#util#Windo(command)
    let s:currentWindow = winnr()
    try
        execute "windo " . a:command
    finally
        execute s:currentWindow. "wincmd w"
        unlet s:currentWindow
    endtry
endfunction

" TODO(arslan): I couldn't parameterize the highlight types. Check if we can
" simplify the following functions

function! go#util#EchoSuccess(msg)
    redraws! | echon "vim-go: " | echohl Function | echon a:msg | echohl None
endfunction

function! go#util#EchoError(msg)
    redraws! | echon "vim-go: " | echohl ErrorMsg | echon a:msg | echohl None
endfunction

function! go#util#EchoWarning(msg)
    redraws! | echon "vim-go: " | echohl WarningMsg | echon a:msg | echohl None
endfunction

function! go#util#EchoProgress(msg)
    redraws! | echon "vim-go: " | echohl Identifier | echon a:msg | echohl None
endfunction

" vim: sw=2 ts=2 et