uuid decode vim test

uuiddecode.vim

"  UUID
"  0                   1                   2                   3
"  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
" +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
" |                          time_low                             |
" +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
" |       time_mid                |         time_hi_and_version   |
" +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
" |clk_seq_hi_res |  clk_seq_low  |         node (0-1)            |
" +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
" |                         node (2-5)                            |
" +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
"
" hex string xxxxxxxx-xxxx-xxxx-Nxxx-xxxxxxxxxxxx

let s:uuidregex = '\x\{8}-\x\{4}-\x\{4}-\x\{4}-\x\{12}'
let s:uuid = {
      \ 'uuid_hex': '',
      \ 'string'  : {
      \   'time_low'            : '',
      \   'time_mid'            : '',
      \   'time_hi_and_version' : '',
      \   'clock'               : '',
      \   'node'                : '',
      \ },
      \ 'bytes' : [],
      \ 'value'   : {
      \   'time_low'            : [],
      \   'time_mid'            : [],
      \   'time_hi_and_version' : [],
      \   'clk_seq_hi_res'      : [],
      \   'clk_seq_low'         : [],
      \   'node'                : [],
      \ },
      \ 'version' : 0,
      \ 'variant' : 0,
      \}


function! s:uuiddecoder(uuid) abort
  let data = a:uuid

  " little endian : hex-string
  " big    endian : data sequence
  let uuiddecode = deepcopy(s:uuid)

  if data =~# s:uuidregex
    let uuiddecode.uuid_hex  = data

    let uuiddecode.string.time_low             = data[0:7]
    " data[8] = '-'
    let uuiddecode.string.time_mid             = data[9:12]
    " data[13] = '-'
    let uuiddecode.string.time_hi_and_version  = data[14:17]
    " data[18] = '-'
    let uuiddecode.string.clock                = data[19:22]
    " data[23] = '-'
    let uuiddecode.string.node                 = data[24:36]

    let uuiddecode.value.time_low             = s:_le2be_dword(s:_str2bytes(uuiddecode.string.time_low))
    let uuiddecode.value.time_mid             = s:_le2be_word(s:_str2bytes(uuiddecode.string.time_mid))
    let uuiddecode.value.time_hi_and_version  = s:_le2be_word(s:_str2bytes(uuiddecode.string.time_hi_and_version))
    let uuiddecode.value.clk_seq_hi_res       = s:_str2bytes(uuiddecode.string.clock[0:1])
    let uuiddecode.value.clk_seq_low          = s:_str2bytes(uuiddecode.string.clock[2:3])
    let uuiddecode.value.node                 = 
          \ s:_le2be_word(s:_str2bytes(uuiddecode.string.node[0:1]))
          \ + s:_le2be_dword(s:_str2bytes(uuiddecode.string.node[2:5]))

    let uuiddecode.bytes = uuiddecode.value.time_low
          \ + uuiddecode.value.time_mid
          \ + uuiddecode.value.time_hi_and_version
          \ + uuiddecode.value.clk_seq_hi_res
          \ + uuiddecode.value.clk_seq_low
          \ + uuiddecode.value.node
  else
    throw 'vital: Data.UUID: format error'
  endif

  return uuiddecode
endfunction

function! s:_le2be_word(data) abort
  return reverse(copy(a:data[0:1]))
endfunction

function! s:_le2be_dword(data) abort
  return reverse(copy(a:data[0:3]))
endfunction

function! s:_str2bytes(str) abort
  return map(range(len(a:str)), 'char2nr(a:str[v:val])')
endfunction

" UEFI system partition GUID
echomsg string(s:uuiddecoder('C12A7328-F81F-11D2-BA4B-00A0C93EC93B'))