" don't spam the user when Vim is started in Vi compatibility mode
let s:cpo_save = &cpo
set cpo&vim

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

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

" LineEnding returns the correct line ending, based on the current fileformat
function! go#util#LineEnding() abort
  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(...) abort
  return join(a:000, go#util#PathSep())
endfunction

" IsWin returns 1 if current OS is Windows or 0 otherwise
" Note that has('win32') is always 1 when has('win64') is 1, so has('win32') is enough.
function! go#util#IsWin() abort
  return has('win32')
endfunction

" IsMac returns 1 if current OS is macOS or 0 otherwise.
function! go#util#IsMac() abort
  return has('mac') ||
        \ has('macunix') ||
        \ has('gui_macvim') ||
        \ go#util#Exec(['uname'])[0] =~? '^darwin'
endfunction

 " Checks if using:
 " 1) Windows system,
 " 2) And has cygpath executable,
 " 3) And uses *sh* as 'shell'
function! go#util#IsUsingCygwinShell()
  return go#util#IsWin() && executable('cygpath') && &shell =~ '.*sh.*'
endfunction

" Check if Vim jobs API is supported.
"
" The (optional) first parameter can be added to indicate the 'cwd' or 'env'
" parameters will be used, which wasn't added until a later version.
function! go#util#has_job(...) abort
  return has('job') || has('nvim')
endfunction

let s:env_cache = {}

" env returns the go environment variable for the given key. Where key can be
" GOARCH, GOOS, GOROOT, etc... It caches the result and returns the cached
" version.
function! go#util#env(key) abort
  let l:key = tolower(a:key)
  if has_key(s:env_cache, l:key)
    return s:env_cache[l:key]
  endif

  if executable('go')
    let l:var = call('go#util#'.l:key, [])
    if go#util#ShellError() != 0
      call go#util#EchoError(printf("'go env %s' failed", toupper(l:key)))
      return ''
    endif
  else
    let l:var = eval("$".toupper(a:key))
  endif

  let s:env_cache[l:key] = l:var
  return l:var
endfunction

" goarch returns 'go env GOARCH'. This is an internal function and shouldn't
" be used. Instead use 'go#util#env("goarch")'
function! go#util#goarch() abort
  return substitute(s:exec(['go', 'env', 'GOARCH'])[0], '\n', '', 'g')
endfunction

" goos returns 'go env GOOS'. This is an internal function and shouldn't
" be used. Instead use 'go#util#env("goos")'
function! go#util#goos() abort
  return substitute(s:exec(['go', 'env', 'GOOS'])[0], '\n', '', 'g')
endfunction

" goroot returns 'go env GOROOT'. This is an internal function and shouldn't
" be used. Instead use 'go#util#env("goroot")'
function! go#util#goroot() abort
  return substitute(s:exec(['go', 'env', 'GOROOT'])[0], '\n', '', 'g')
endfunction

" gopath returns 'go env GOPATH'. This is an internal function and shouldn't
" be used. Instead use 'go#util#env("gopath")'
function! go#util#gopath() abort
  return substitute(s:exec(['go', 'env', 'GOPATH'])[0], '\n', '', 'g')
endfunction

" gomod returns 'go env GOMOD'. gomod changes depending on the folder. Don't
" use go#util#env as it caches the value.
function! go#util#gomod() abort
  return substitute(s:exec(['go', 'env', 'GOMOD'])[0], '\n', '', 'g')
endfunction

" gomodcache returns 'go env GOMODCACHE'. Instead use 'go#util#env("gomodcache")'
function! go#util#gomodcache() abort
  return substitute(s:exec(['go', 'env', 'GOMODCACHE'])[0], '\n', '', 'g')
endfunction

" hostosarch returns the OS and ARCH values that the go binary is intended for.
function! go#util#hostosarch() abort
  let [l:hostos, l:err] = s:exec(['go', 'env', 'GOHOSTOS'])
  let [l:hostarch, l:err] = s:exec(['go', 'env', 'GOHOSTARCH'])
  return [substitute(l:hostos, '\n', '', 'g'), substitute(l:hostarch, '\n', '', 'g')]
endfunction

" go#util#ModuleRoot returns the root directory of the module of the current
" buffer.
function! go#util#ModuleRoot() abort
  let [l:out, l:err] = go#util#ExecInDir(['go', 'env', 'GOMOD'])
  if l:err != 0
    return -1
  endif

  let l:module = split(l:out, '\n', 1)[0]

  " When run with `GO111MODULE=on and not in a module directory, the module will be reported as /dev/null.
  let l:fakeModule = '/dev/null'
  if go#util#IsWin()
    let l:fakeModule = 'NUL'
  endif

  if l:fakeModule == l:module
    return expand('%:p:h')
  endif

  return resolve(fnamemodify(l:module, ':p:h'))
endfunction

" Run a shell command.
"
" It will temporary set the shell to /bin/sh for Unix-like systems if possible,
" so that we always use a standard POSIX-compatible Bourne shell (and not e.g.
" csh, fish, etc.) See #988 and #1276.
function! s:system(cmd, ...) abort
  " Preserve original shell, shellredir and shellcmdflag values
  let l:shell = &shell
  let l:shellredir = &shellredir
  let l:shellcmdflag = &shellcmdflag

  if !go#util#IsWin() && executable('/bin/sh')
      set shell=/bin/sh shellredir=>%s\ 2>&1 shellcmdflag=-c
  endif

  if go#util#IsWin()
    if executable($COMSPEC)
      let &shell = $COMSPEC
      set shellcmdflag=/C
    endif
  endif

  try
    return call('system', [a:cmd] + a:000)
  finally
    " Restore original values
    let &shell = l:shell
    let &shellredir = l:shellredir
    let &shellcmdflag = l:shellcmdflag
  endtry
endfunction

" System runs a shell command "str". Every arguments after "str" is passed to
" stdin.
function! go#util#System(str, ...) abort
  return call('s:system', [a:str] + a:000)
endfunction

" Exec runs a shell command "cmd", which must be a list, one argument per item.
" Every list entry will be automatically shell-escaped
" Every other argument is passed to stdin.
function! go#util#Exec(cmd, ...) abort
  if len(a:cmd) == 0
    call go#util#EchoError("go#util#Exec() called with empty a:cmd")
    return ['', 1]
  endif

  let l:bin = a:cmd[0]

  " Lookup the full path, respecting settings such as 'go_bin_path'. On errors,
  " CheckBinPath will show a warning for us.
  let l:bin = go#path#CheckBinPath(l:bin)
  if empty(l:bin)
    return ['', 1]
  endif

  " Finally execute the command using the full, resolved path. Do not pass the
  " unmodified command as the correct program might not exist in $PATH.
  return call('s:exec', [[l:bin] + a:cmd[1:]] + a:000)
endfunction

" ExecInDir will execute cmd with the working directory set to the current
" buffer's directory.
function! go#util#ExecInDir(cmd, ...) abort
  let l:wd = expand('%:p:h')
  return call('go#util#ExecInWorkDir', [a:cmd, l:wd] + a:000)
endfunction

" ExecInWorkDir will execute cmd with the working diretory set to wd. Additional arguments will be passed
" to cmd.
function! go#util#ExecInWorkDir(cmd, wd, ...) abort
  if !isdirectory(a:wd)
    return ['', 1]
  endif

  let l:dir = go#util#Chdir(a:wd)
  try
    let [l:out, l:err] = call('go#util#Exec', [a:cmd] + a:000)
  finally
    call go#util#Chdir(l:dir)
  endtry
  return [l:out, l:err]
endfunction

function! s:exec(cmd, ...) abort
  let l:bin = a:cmd[0]
  let l:cmd = go#util#Shelljoin([l:bin] + a:cmd[1:])
  if go#util#HasDebug('shell-commands')
    call go#util#EchoInfo('shell command: ' . l:cmd)
  endif

  let l:out = call('s:system', [l:cmd] + a:000)
  return [l:out, go#util#ShellError()]
endfunction

function! go#util#ShellError() abort
  return v: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) abort
  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) abort
  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, ...) abort
  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)
  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, ...) abort
  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) abort
  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() abort
  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) abort
  let s:currentWindow = winnr()
  try
    execute "windo " . a:command
  finally
    execute s:currentWindow. "wincmd w"
    unlet s:currentWindow
  endtry
endfunction

" snippetcase converts the given word to given preferred snippet setting type
" case.
function! go#util#snippetcase(word) abort
  let l:snippet_case = go#config#AddtagsTransform()
  if l:snippet_case == "snakecase"
    return go#util#snakecase(a:word)
  elseif l:snippet_case == "camelcase"
    return go#util#camelcase(a:word)
  else
    return a:word " do nothing
  endif
endfunction

" snakecase converts a string to snake case. i.e: FooBar -> foo_bar
" Copied from tpope/vim-abolish
function! go#util#snakecase(word) abort
  let word = substitute(a:word, '::', '/', 'g')
  let word = substitute(word, '\(\u\+\)\(\u\l\)', '\1_\2', 'g')
  let word = substitute(word, '\(\l\|\d\)\(\u\)', '\1_\2', 'g')
  let word = substitute(word, '[.-]', '_', 'g')
  let word = tolower(word)
  return word
endfunction

" camelcase converts a string to camel case. e.g. FooBar or foo_bar will become
" fooBar.
" Copied from tpope/vim-abolish.
function! go#util#camelcase(word) abort
  let word = substitute(a:word, '-', '_', 'g')
  if word !~# '_' && word =~# '\l'
    return substitute(word, '^.', '\l&', '')
  else
    return substitute(word, '\C\(_\)\=\(.\)', '\=submatch(1)==""?tolower(submatch(2)) : toupper(submatch(2))','g')
  endif
endfunction

" pascalcase converts a string to 'PascalCase'. e.g. fooBar or foo_bar will
" become FooBar.
function! go#util#pascalcase(word) abort
  let word = go#util#camelcase(a:word)
  return toupper(word[0]) . word[1:]
endfunction

" Echo a message to the screen and highlight it with the group in a:hi.
"
" The message can be a list or string; every line with be :echomsg'd separately.
function! s:echo(msg, hi)
  let l:msg = []
  if type(a:msg) != type([])
    let l:msg = split(a:msg, "\n")
  else
    let l:msg = a:msg
  endif

  " Tabs display as ^I or <09>, so manually expand them.
  let l:msg = map(l:msg, 'substitute(v:val, "\t", "        ", "")')

  exe 'echohl ' . a:hi
  for line in l:msg
    echom "vim-go: " . line
  endfor
  echohl None
endfunction

function! go#util#EchoSuccess(msg)
  call s:echo(a:msg, 'Function')
endfunction
function! go#util#EchoError(msg)
  call s:echo(a:msg, 'ErrorMsg')
endfunction
function! go#util#EchoWarning(msg)
  call s:echo(a:msg, 'WarningMsg')
endfunction
function! go#util#EchoProgress(msg)
  redraw
  call s:echo(a:msg, 'Identifier')
endfunction
function! go#util#EchoInfo(msg)
  call s:echo(a:msg, 'Debug')
endfunction

" Get all lines in the buffer as a a list.
function! go#util#GetLines()
  let buf = getline(1, '$')
  if &encoding != 'utf-8'
    let buf = map(buf, 'iconv(v:val, &encoding, "utf-8")')
  endif
  if &l:fileformat == 'dos'
    " XXX: line2byte() depend on 'fileformat' option.
    " so if fileformat is 'dos', 'buf' must include '\r'.
    let buf = map(buf, 'v:val."\r"')
  endif
  return buf
endfunction

" Convert the current buffer to the "archive" format of
" golang.org/x/tools/go/buildutil:
" https://godoc.org/golang.org/x/tools/go/buildutil#ParseOverlayArchive
"
" > The archive consists of a series of files. Each file consists of a name, a
" > decimal file size and the file contents, separated by newlinews. No newline
" > follows after the file contents.
function! go#util#archive()
    let l:buffer = join(go#util#GetLines(), "\n")
    return expand("%:p:gs!\\!/!") . "\n" . strlen(l:buffer) . "\n" . l:buffer
endfunction

" Make a named temporary directory which starts with "prefix".
"
" Unfortunately Vim's tempname() is not portable enough across various systems;
" see: https://github.com/mattn/vim-go/pull/3#discussion_r138084911
function! go#util#tempdir(prefix) abort
  " See :help tempfile
  if go#util#IsWin()
    let l:dirs = [$TMP, $TEMP, 'c:\tmp', 'c:\temp']
  else
    let l:dirs = [$TMPDIR, '/tmp', './', $HOME]
  endif

  let l:dir = ''
  for l:d in dirs
    if !empty(l:d) && filewritable(l:d) == 2
      let l:dir = l:d
      break
    endif
  endfor

  if l:dir == ''
    call go#util#EchoError('Unable to find directory to store temporary directory in')
    return
  endif

  " Not great randomness, but "good enough" for our purpose here.
  let l:rnd = sha256(printf('%s%s', reltimestr(reltime()), fnamemodify(bufname(''), ":p")))
  let l:tmp = printf("%s/%s%s", l:dir, a:prefix, l:rnd)
  call mkdir(l:tmp, 'p', 0700)
  return l:tmp
endfunction

" Report if the user enabled a debug flag in g:go_debug.
function! go#util#HasDebug(flag)
  return index(go#config#Debug(), a:flag) >= 0
endfunction

function! go#util#OpenBrowser(url) abort
    let l:cmd = go#config#PlayBrowserCommand()
    if len(l:cmd) == 0
        redraw
        echohl WarningMsg
        echo "It seems that you don't have general web browser. Open URL below."
        echohl None
        echo a:url
        return
    endif

    " if setting starts with a !.
    if l:cmd =~ '^!'
        let l:cmd = substitute(l:cmd, '%URL%', '\=escape(shellescape(a:url), "#")', 'g')
        silent! exec l:cmd
    elseif cmd =~ '^:[A-Z]'
        let l:cmd = substitute(l:cmd, '%URL%', '\=escape(a:url,"#")', 'g')
        exec l:cmd
    else
        let l:cmd = substitute(l:cmd, '%URL%', '\=shellescape(a:url)', 'g')
        call go#util#System(l:cmd)
    endif
endfunction

function! go#util#ParseErrors(lines) abort
  let errors = []

  for line in a:lines
    let fatalerrors = matchlist(line, '^\(fatal error:.*\)$')
    let tokens = matchlist(line, '^\s*\(.\{-}\):\(\d\+\):\s*\(.*\)')

    if !empty(fatalerrors)
      call add(errors, {"text": fatalerrors[1]})
    elseif !empty(tokens)
      " strip endlines of form ^M
      let out = substitute(tokens[3], '\r$', '', '')

      call add(errors, {
            \ "filename" : fnamemodify(tokens[1], ':p'),
            \ "lnum"     : tokens[2],
            \ "text"     : out,
            \ })
    elseif !empty(errors)
      " Preserve indented lines.
      " This comes up especially with multi-line test output.
      if match(line, '^\s') >= 0
        call add(errors, {"text": substitute(line, '\r$', '', '')})
      endif
    endif
  endfor

  return errors
endfunction

function! go#util#ShowInfo(info)
  if empty(a:info)
    return
  endif

  echo "vim-go: " | echohl Function | echon a:info | echohl None
endfunction

" go#util#SetEnv takes the name of an environment variable and what its value
" should be and returns a function that will restore it to its original value.
function! go#util#SetEnv(name, value) abort
  let l:state = {}

  if len(a:name) == 0
    return function('s:noop', [], l:state)
  endif

  let l:remove = 0
  if exists('$' . a:name)
    let l:oldvalue = eval('$' . a:name)
  else
    let l:remove = 1
  endif

  " wrap the value in single quotes so that it will work on windows when there
  " are backslashes present in the value (e.g. $PATH).
  call execute('let $' . a:name . " = '" . a:value . "'")

  if l:remove
    return function('s:unset', [a:name], l:state)
  endif

  return function('go#util#SetEnv', [a:name, l:oldvalue], l:state)
endfunction

function! go#util#ClearHighlights(group) abort
  if has('textprop')
    " the property type may not exist when syntax highlighting is not enabled.
    if empty(prop_type_get(a:group))
      return
    endif
    if !has('patch-8.1.1035')
      return prop_remove({'type': a:group, 'all': 1}, 1, line('$'))
    endif
    return prop_remove({'type': a:group, 'all': 1})
  endif

  if exists("*matchaddpos")
    return s:clear_group_from_matches(a:group)
  endif
endfunction

function! s:clear_group_from_matches(group) abort
  let l:cleared = 0

  let m = getmatches()
  for item in m
    if item['group'] == a:group
      call matchdelete(item['id'])
      let l:cleared = 1
    endif
  endfor

  return l:cleared
endfunction

function! s:unset(name) abort
  try
    " unlet $VAR was introducted in Vim 8.0.1832, which is newer than the
    " minimal version that vim-go supports. Set the environment variable to
    " the empty string in that case. It's not perfect, but it will work fine
    " for most things, and is really the best alternative that's available.
    if !has('patch-8.0.1832')
      call go#util#SetEnv(a:name, '')
      return
    endif

    call execute('unlet $' . a:name)
  catch
    call go#util#EchoError(printf('could not unset $%s: %s', a:name, v:exception))
  endtry
endfunction

function! s:noop(...) abort dict
endfunction

" go#util#HighlightPositions highlights using text properties if possible and
" falls back to matchaddpos() if necessary. It works around matchaddpos()'s
" limit of only 8 positions per call by calling matchaddpos() with no more
" than 8 positions per call.
"
" pos should be a list of 3 element lists. The lists should be [line, col,
" length] as used by matchaddpos().
function! go#util#HighlightPositions(group, pos) abort
  if has('textprop')
    for l:pos in a:pos
      " use a single line prop by default
      let l:prop = {'type': a:group, 'length': l:pos[2]}

      let l:line = getline(l:pos[0])

      " l:max is the 1-based index within the buffer of the first character after l:pos.
      let l:max = line2byte(l:pos[0]) + l:pos[1] + l:pos[2] - 1
      if has('patch-8.2.115')
        " Use byte2line as long as 8.2.115 (which resolved
        " https://github.com/vim/vim/issues/5334) is available.
        let l:end_lnum = byte2line(l:max)

        " specify end line and column if needed.
        if l:pos[0] != l:end_lnum
          let l:end_col = l:max - line2byte(l:end_lnum)
          let l:prop = {'type': a:group, 'end_lnum': l:end_lnum, 'end_col': l:end_col}
        endif
      elseif l:pos[1] + l:pos[2] - 1 > len(l:line)
        let l:end_lnum = l:pos[0]
        while line2byte(l:end_lnum+1) < l:max
          let l:end_lnum += 1
        endwhile

        " l:end_col is the full length - the byte position of l:end_lnum +
        " the number of newlines (number of newlines is l:end_lnum -
        " l:pos[0].
        let l:end_col = l:max - line2byte(l:end_lnum) + l:end_lnum - l:pos[0]
        let l:prop = {'type': a:group, 'end_lnum': l:end_lnum, 'end_col': l:end_col}
      endif
      try
        call prop_add(l:pos[0], l:pos[1], l:prop)
      catch
        " Swallow any exceptions encountered while trying to add the property
        " Due to the asynchronous nature, it's possible that the buffer has
        " changed since the buffer was analyzed and that the specified
        " position is no longer valid.
      endtry
    endfor
    return
  endif

  if exists('*matchaddpos')
    return s:matchaddpos(a:group, a:pos)
  endif
endfunction

" s:matchaddpos works around matchaddpos()'s limit of only 8 positions per
" call by calling matchaddpos() with no more than 8 positions per call.
function! s:matchaddpos(group, pos) abort
  let l:partitions = []
  let l:partitionsIdx = 0
  let l:posIdx = 0
  for l:pos in a:pos
    if l:posIdx % 8 == 0
      let l:partitions = add(l:partitions, [])
      let l:partitionsIdx = len(l:partitions) - 1
    endif
    let l:partitions[l:partitionsIdx] = add(l:partitions[l:partitionsIdx], l:pos)
    let l:posIdx = l:posIdx + 1
  endfor

  for l:positions in l:partitions
    call matchaddpos(a:group, l:positions)
  endfor
endfunction

function! go#util#Chdir(dir) abort
  if !exists('*chdir')
    let l:olddir = getcwd()
    let cd = exists('*haslocaldir') && haslocaldir() ? 'lcd ' : 'cd '
    execute cd . fnameescape(a:dir)
    return l:olddir
  endif
  return chdir(a:dir)
endfunction

" restore Vi compatibility settings
let &cpo = s:cpo_save
unlet s:cpo_save

" vim: sw=2 ts=2 et