nuwiki/autoload/nuwiki/complete.vim

" autoload/nuwiki/complete.vim — command-line completion for the
" :Vimwiki*/:Nuwiki* commands (mirrors upstream vimwiki's -complete= specs).
"
" Pure client-side and synchronous: candidates come from config and the
" filesystem, never the LSP, so a `-complete=customlist,{fn}` attribute can
" call these directly under vim-lsp, coc, and Neovim alike.
"
" NOTE on files/RenameFile: upstream's :VimwikiRenameFile takes a new-name arg
" with file completion because upstream performs the rename itself. nuwiki
" delegates renaming to the LSP rename request (`:LspRename` / coc `rename`),
" which drives its own interactive prompt — there is no filename argument to
" complete, so no file completer is provided (documented divergence).

" Page-name completion (VimwikiGoto). Globs every configured wiki root for its
" `*<ext>` files and returns their root-relative names with the extension
" stripped, filtered by {arglead}. Mirrors upstream complete_links_raw.
function! nuwiki#complete#pages(arglead, cmdline, cursorpos) abort
  let l:names = {}
  for l:w in nuwiki#commands#wiki_list()
    let l:root = substitute(get(l:w, 'root', ''), '/\+$', '', '')
    if l:root ==# '' | continue | endif
    let l:ext = get(l:w, 'ext', '.wiki')
    for l:f in glob(l:root . '/**/*' . l:ext, 0, 1)
      let l:rel = l:f[len(l:root) + 1 :]
      if l:rel ==# '' | continue | endif
      let l:rel = l:rel[: -len(l:ext) - 1]
      let l:names[l:rel] = 1
    endfor
  endfor
  return filter(sort(keys(l:names)), 'stridx(v:val, a:arglead) == 0')
endfunction

" Colour completion (VimwikiColorize) — keys from any configured `color_dic`
" (per-wiki `g:nuwiki_wikis[].color_dic` or the scalar `g:nuwiki_color_dic`)
" plus colours already used in `color:NAME` spans in the current buffer.
function! nuwiki#complete#colors(arglead, cmdline, cursorpos) abort
  let l:set = {}
  for l:w in get(g:, 'nuwiki_wikis', [])
    for l:k in keys(get(l:w, 'color_dic', {}))
      let l:set[l:k] = 1
    endfor
  endfor
  for l:k in keys(get(g:, 'nuwiki_color_dic', {}))
    let l:set[l:k] = 1
  endfor
  for l:line in getline(1, '$')
    let l:start = 0
    while 1
      let l:m = matchstrpos(l:line, 'color:\s*\zs[^"'';)]\+', l:start)
      if l:m[1] < 0 | break | endif
      let l:set[trim(l:m[0])] = 1
      let l:start = l:m[2]
    endwhile
  endfor
  return filter(sort(keys(l:set)), 'stridx(v:val, a:arglead) == 0')
endfunction

" Tag completion (VimwikiSearchTags / VimwikiGenerateTagLinks). The tag index
" lives in the LSP server, which a synchronous completer can't query, so we
" harvest `:tag:` tokens by scanning the configured wikis' files directly —
" the same source the server indexes. Runs only on <Tab> at the `:` line.
function! nuwiki#complete#tags(arglead, cmdline, cursorpos) abort
  let l:set = {}
  for l:w in nuwiki#commands#wiki_list()
    let l:root = substitute(get(l:w, 'root', ''), '/\+$', '', '')
    if l:root ==# '' | continue | endif
    let l:ext = get(l:w, 'ext', '.wiki')
    for l:f in glob(l:root . '/**/*' . l:ext, 0, 1)
      for l:line in readfile(l:f)
        " Tags come in colon-delimited runs like `:foo:bar:` (no spaces).
        " Match a whole run, then split out each tag (adjacent tags share a
        " colon, so a per-tag scan would miss every other one).
        let l:start = 0
        while 1
          let l:m = matchstrpos(l:line, ':\%([^:[:space:]]\+:\)\+', l:start)
          if l:m[1] < 0 | break | endif
          for l:t in split(l:m[0], ':')
            if l:t !=# '' | let l:set[l:t] = 1 | endif
          endfor
          let l:start = l:m[2]
        endwhile
      endfor
    endfor
  endfor
  return filter(sort(keys(l:set)), 'stridx(v:val, a:arglead) == 0')
endfunction