" install necessary Go tools
if exists("g:go_loaded_install")
  finish
endif
let g:go_loaded_install = 1

" these packages are used by vim-go and can be automatically installed if
" needed by the user with GoInstallBinaries
let s:packages = [
      \ "github.com/nsf/gocode",
      \ "github.com/alecthomas/gometalinter",
      \ "golang.org/x/tools/cmd/goimports",
      \ "golang.org/x/tools/cmd/guru",
      \ "golang.org/x/tools/cmd/gorename",
      \ "github.com/golang/lint/golint",
      \ "github.com/rogpeppe/godef",
      \ "github.com/kisielk/errcheck",
      \ "github.com/jstemmer/gotags",
      \ "github.com/klauspost/asmfmt/cmd/asmfmt",
      \ "github.com/fatih/motion",
      \ "github.com/fatih/gomodifytags",
      \ "github.com/zmb3/gogetdoc",
      \ "github.com/josharian/impl",
      \ ]

" These commands are available on any filetypes
command! GoInstallBinaries call s:GoInstallBinaries(-1)
command! GoUpdateBinaries call s:GoInstallBinaries(1)
command! -nargs=? -complete=dir GoPath call go#path#GoPath(<f-args>)

" GoInstallBinaries downloads and install all necessary binaries stated in the
" packages variable. It uses by default $GOBIN or $GOPATH/bin as the binary
" target install directory. GoInstallBinaries doesn't install binaries if they
" exist, to update current binaries pass 1 to the argument.
function! s:GoInstallBinaries(updateBinaries)
  let err = s:CheckBinaries()
  if err != 0
    return
  endif

  if go#path#Default() == ""
    echohl Error
    echomsg "vim.go: $GOPATH is not set and 'go env GOPATH' returns empty"
    echohl None
    return
  endif

  let go_bin_path = go#path#BinPath()

  " change $GOBIN so go get can automatically install to it
  let $GOBIN = go_bin_path

  " old_path is used to restore users own path
  let old_path = $PATH

  " vim's executable path is looking in PATH so add our go_bin path to it
  let $PATH = go_bin_path . go#util#PathListSep() . $PATH

  " when shellslash is set on MS-* systems, shellescape puts single quotes
  " around the output string. cmd on Windows does not handle single quotes
  " correctly. Unsetting shellslash forces shellescape to use double quotes
  " instead.
  let resetshellslash = 0
  if has('win32') && &shellslash
    let resetshellslash = 1
    set noshellslash
  endif

  let cmd = "go get -v "
  if get(g:, "go_get_update", 1) != 0
    let cmd .= "-u "
  endif

  let s:go_version = matchstr(go#util#System("go version"), '\d.\d.\d')

  " https://github.com/golang/go/issues/10791
  if s:go_version > "1.4.0" && s:go_version < "1.5.0"
    let cmd .= "-f "
  endif

  for pkg in s:packages
    let basename = fnamemodify(pkg, ":t")
    let binname = "go_" . basename . "_bin"

    let bin = basename
    if exists("g:{binname}")
      let bin = g:{binname}
    endif

    if !executable(bin) || a:updateBinaries == 1
      if a:updateBinaries == 1
        echo "vim-go: Updating ". basename .". Reinstalling ". pkg . " to folder " . go_bin_path
      else
        echo "vim-go: ". basename ." not found. Installing ". pkg . " to folder " . go_bin_path
      endif


      let out = go#util#System(cmd . shellescape(pkg))
      if go#util#ShellError() != 0
        echo "Error installing ". pkg . ": " . out
      endif
    endif
  endfor

  " restore back!
  let $PATH = old_path
  if resetshellslash
    set shellslash
  endif
endfunction

" CheckBinaries checks if the necessary binaries to install the Go tool
" commands are available.
function! s:CheckBinaries()
  if !executable('go')
    echohl Error | echomsg "vim-go: go executable not found." | echohl None
    return -1
  endif

  if !executable('git')
    echohl Error | echomsg "vim-go: git executable not found." | echohl None
    return -1
  endif
endfunction

" Autocommands
" ============================================================================
"
function! s:echo_go_info()
  if !get(g:, "go_echo_go_info", 1)
    return
  endif

  if !exists('v:completed_item') || empty(v:completed_item)
    return
  endif
  let item = v:completed_item

  if !has_key(item, "info")
    return
  endif

  if empty(item.info)
    return
  endif

  redraws! | echo "vim-go: " | echohl Function | echon item.info | echohl None
endfunction

function! s:auto_type_info()
  " GoInfo automatic update
  if get(g:, "go_auto_type_info", 0)
    call go#tool#Info(1)
  endif
endfunction

function! s:auto_sameids()
  " GoSameId automatic update
  if get(g:, "go_auto_sameids", 0)
    call go#guru#SameIds()
  endif
endfunction

function! s:fmt_autosave()
  " Go code formatting on save
  if get(g:, "go_fmt_autosave", 1)
    call go#fmt#Format(-1)
  endif
endfunction

function! s:asmfmt_autosave()
  " Go asm formatting on save
  if get(g:, "go_asmfmt_autosave", 0)
    call go#asmfmt#Format()
  endif
endfunction

function! s:metalinter_autosave()
  " run gometalinter on save
  if get(g:, "go_metalinter_autosave", 0)
    call go#lint#Gometa(1)
  endif
endfunction

function! s:template_autocreate()
  " create new template from scratch
  if get(g:, "go_template_autocreate", 1)
    call go#template#create()
  endif
endfunction

augroup vim-go
  autocmd!

  autocmd CursorHold *.go call s:auto_type_info()
  autocmd CursorHold *.go call s:auto_sameids()

  " Echo the identifier information when completion is done. Useful to see
  " the signature of a function, etc...
  if exists('##CompleteDone')
    autocmd CompleteDone *.go call s:echo_go_info()
  endif

  autocmd BufWritePre *.go call s:fmt_autosave()
  autocmd BufWritePre *.s call s:asmfmt_autosave()
  autocmd BufWritePost *.go call s:metalinter_autosave()
  autocmd BufNewFile *.go call s:template_autocreate()
  " clear SameIds when the buffer is unloaded so that loading another buffer
  " in the same window doesn't highlight the most recently matched
  " identifier's positions.
  autocmd BufWinEnter *.go call go#guru#ClearSameIds()
augroup END

" vim: sw=2 ts=2 et