c4ctrl/c4ctrl.vim

" c4ctrl.vim: This Vim plugin makes some functionality of the c4ctrl command
"             line utility available from within Vim.
"
" Last Change: 2017 Apr 16
" Maintainer: Shy
" License: This file is placed in the public domain.
"
" Usage: C4ctrl [get | kitchentext [REGISTER] | open PRESET |
"                set [w] [p] [f] [-magic] | write PRESET]

if exists("g:loaded_c4ctrl")
  finish
endif
let g:loaded_c4ctrl = 1


" ************************************************************************** "
" Utility function: Find the path to the c4ctrl configuration directory and  "
" return it as string.                                                       "
" ************************************************************************** "
function s:FindConfigDir() " {{{1

  " Return early if we already know it from an earlier invocation.
  if exists("s:config_dir")
    return s:config_dir
  endif

  if expand("$XDG_CONFIG_HOME") != "$XDG_CONFIG_HOME"
    let s:config_dir = expand("$XDG_CONFIG_HOME/c4ctrl/")
  else
    let s:config_dir = expand("$HOME/.config/c4ctrl/")
  endif

  if !isdirectory(s:config_dir)
    redraw
    echohl WarningMsg
    echo "Error: could not access config directory: ".s:config_dir."!"
    echohl None
    return ""
  endif
  return s:config_dir
endfunction " }}}1


" ************************************************************************** "
" Make some functionality of the 'c4ctrl' command line utility available     "
" from within Vim.                                                           "
" Available commands are 'get', 'kitchentext', 'open', 'set' and 'write'.    "
" Arguments:                                                                 "
"   prev_cursor_pos   -- cursor position as returned by getcurpos()          "
"   mods              -- modifiers (:command variable <f-mods>)              "
"   first_line        -- first line of range (:command <line1>)              "
"   last_line         -- last line of range (:command <line2>)               "
"   command           -- user command ('get', 'set' etc.)                    "
"   [...]             -- optional command options                            "
" ************************************************************************** "
function C4ctrl(prev_cursor_pos, mods, first_line, last_line, command, ...) range " {{{1

  try " We utilize the finally section to clean up the environment later on.

    " Name of the executable.
    let s:c4ctrl = "c4ctrl"
  
    " ********************************************************************** "
    " Utility function to print out a warning message.                       "
    " ********************************************************************** "
    function! s:Warn(message) " {{{2

      redraw
      echohl WarningMsg
      echo a:message
      echohl None

    endfunction " }}}2

    " ********************************************************************** "
    " Utility function to be called after a preset has been loaded.          "
    " ********************************************************************** "
    function! s:SynHighlight() " {{{2
  
      syn clear
      " Match topics
      syn match Identifier "^\s*[[:alnum:]/]\+\ze\s*="
      " Match color values with 3 digits
      syn match Number "=\s*\zs\%(\s*\x\)\{3}"
      " Match color values with 6 digits
      syn match Number "=\s*\zs\%(\s*\x\)\{6}"
      " Match comments
      syn match Comment "^\s*#.*" 
      " Match error: too few digits
      syn match Error "=\s*\zs\x\{1,2}\s*$"
      " Match error: invalid chars as digit
      syn match Error "=\s*\zs.*[^[:blank:][:xdigit:]]\+.*"
      "syn match Error "=\s*\zs.*\%(\S\&\X\)\+.*"

      " Move the cursor somewhere more practical.
      call cursor(1,1)
      call search("^[^#].*=[ \t]*[0-9a-fA-F]", 'eW')

    endfunction " }}}2
  
    " Check if we can execute c4ctrl or c4ctrl.py and modify the variable
    " s:c4ctrl accordingly if needed.
    if !executable(s:c4ctrl) " {{{2
      " Maybe we just need to add .py to the command?
      if executable(s:c4ctrl.".py")
        let s:c4ctrl .= ".py"
      else
        call s:Warn("Executable not found! Please put \"".s:c4ctrl."\" into your $PATH.")
        unlet s:c4ctrl
        return
      endif
    endif " }}}2
  
    " *************************************************** "
    " Command 'get': Read current status into new buffer. "
    " *************************************************** "
    if stridx("get", a:command) == 0 " {{{2

      execute a:mods "new"
      silent execute "0 read !" s:c4ctrl "-o -"
      if v:shell_error == 0
        call s:SynHighlight()
        set nomodified " Mark as unmodified.
      else
        call s:Warn(printf("Error: %s returned exit code %d!", s:c4ctrl, v:shell_error))
      endif
    " }}}2
  
    " ***************************************************************** "
    " Command 'kitchentext': Send given register or text in range to    "
    " the Kitchenlight.                                                 "
    " ***************************************************************** "
    elseif stridx("kitchentext", a:command) == 0 " {{{2

      let kitchentext = 'kitchentext'
      if !executable(kitchentext)
        call s:Warn('Executable not found! Please put "'.kitchentext.'" into your $PATH.')
        return
      endif

      let command_line = 'kitchentext -f -d 150 -p'
      if exists('a:1')
        " Use text from given register.
        let text = getreg(a:1, 0, 1)
        if text == []
          call s:Warn('Warning: register "'.a:1.'" is empty!")
          return
        endif
      else
        " Use text in range.
        let text = getline(a:first_line, a:last_line)

        " Check if user marked a substring using visual selection.
        " Note: stridx() returns '0' when the second parameter evaluates to an
        " empty string. Thus the leading space in the first parameter.
        if stridx(' v', visualmode()) > 0 && stridx(histget('', -1), "'<,'>") != -1
          let visual_start = getpos("'<")
          let visual_end = getpos("'>")

          " Better safe than sorry: lets check if the last visual selection
          " starts and ends on the same lines as the range we were given.
          if visual_start[1] == a:first_line && visual_end[1] == a:last_line
            if visualmode() == 'v'
              " Beware: text[0] and text[-1] may be the same line of text.
              " Thus this somewhat counter-intuitive order.
              let text[-1] = strpart(text[-1], 0, visual_end[2])
              let text[0] = strpart(text[0], (visual_start[2] - 1))
            else " Box selection.
              call map(text, 'strpart(v:val, 0, '.visual_end[2].')')
              call map(text, 'strpart(v:val, '.(visual_start[2] -1).')')
            endif
          endif " visual_start[1] ...

        else " stridx(' v', ...
          " No visual selection then.
          " Let's warn the user if she's about to put the whole buffer on the
          " Kitchenlight.
          if a:first_line != a:last_line && a:first_line == 1 && a:last_line == line('$')
            let responce = input('Really send the whole buffer to the Kitchenlight? [y/N]: ')
            if responce != 'y' && responce != 'Y'
              redraw
              echo 'Canceled.'
              return
            endif
          endif " a:firt_line != a:last_line ...

        endif " stridx(' v', ...
      endif " exists('a:1')

      " Strip any leading white spaces.
      call map(text, 'substitute(v:val, "^[ \t]*", "", "")')
      let ret = system(command_line, text)
    " }}}2
  
    " ******************************************************* "
    " Command 'open': Load an exiting preset into the buffer. "
    " ******************************************************* "
    elseif stridx("open", a:command) == 0 " {{{2

      if !exists("a:1")
        call s:Warn("Missing filename!")
        return
      endif
  
      let s:config_dir = s:FindConfigDir()
      if s:config_dir == ""
        return
      endif
      let filename = s:config_dir . a:1
      if !filereadable(filename)
        call s:Warn("Error: could not open file ".filename)
        return
      endif
  
      execute a:mods "new"
      execute "edit" fnameescape(filename)
      call s:SynHighlight()
    " }}}2
  
    " *********************************************** "
    " Command 'set': Apply range or buffer as preset. "
    " *********************************************** "
    elseif stridx("set", a:command) == 0 " {{{2

      " Let's start by building a command line.
      let command_line = s:c4ctrl
      let rooms_given = 0
  
      for i in range(a:0)
        let  arg = a:000[i]
        for room in ["wohnzimmer", "plenarsaal", "fnordcenter"]
          if stridx(room, arg) == 0
            let command_line = printf("%s -%s -", command_line, arg[0])
            let rooms_given = 1
          endif
        endfor
        if stridx("-magic", arg) == 0
          let command_line = printf("%s --magic", command_line)
        endif
      endfor
  
      if rooms_given == 0
        " If no room is given, set colors for all rooms.
        let command_line .= " -w - -p - -f -"
      endif
  
      silent let ret = system(command_line, getline(a:first_line, a:last_line))
  
      " Restore cursor position.
      call setpos('.', a:prev_cursor_pos)
    " }}}2
  
    " ************************************************************* "
    " Command 'write': Save buffer as preset into config directory. "
    " ************************************************************* "
    elseif stridx("write", substitute(a:command, "!$", "", "")) == 0 " {{{2

      if !exists("a:1")
        call s:Warn("Missing filename!")
        return
      endif
  
      let s:config_dir = s:FindConfigDir()
      if s:config_dir == ""
        return
      endif
  
      let filename = s:config_dir . a:1
  
      if strridx(a:command, "!") == (len(a:command) - 1)
        " Force if a '!' was appended to the command.
        execute "saveas!" fnameescape(filename)
      else
        execute "saveas" fnameescape(filename)
      endif
      call s:SynHighlight()
    " }}}2
  
    " **************************** "
    " Fallback on unknown command. "
    " Error handling.              "
    " **************************** "
    else " {{{2
      call s:Warn("Unknown command: ".a:command)
      echo "Valid commands are get, kitchentext, open, set and write"
    endif
  
    " Echo return if shell exited with an error.
    if v:shell_error
      if exists("ret")
        echoerr ret
      endif
    endif " }}}2

  " {{{ Clean up environment after C4ctrl().
  finally
    unlet! s:c4ctrl s:config_dir
    delfunction s:SynHighlight
    delfunction s:Warn
  endtry
  " }}}

endfunction " }}}1


" ************************************************************************** "
" Custom command line completion.                                            "
" ************************************************************************** "
function s:C4ctrlCompletion(ArgLead, CmdLine, CursorPos) " {{{1

  " The name of the command we are adding to Vim.
  let command_name = "C4ctrl"
  " A list of current cmd line arguments, stripping everything up to the
  " first capital.
  let command_line = split(strpart(a:CmdLine, match(a:CmdLine, "[A-Z]")))
  " Check out if our name was abbreviated and modify accordingly
  while index(command_line, command_name) == -1
    let command_name = strpart(command_name, 0, len(command_name) - 1) 
    if len(command_name) == 0
      " This should never happen, but let's not risk an infinite loop anyway
      return ""
    endif
  endwhile
  " Position of our command in the command line.
  let command_index = index(command_line, command_name)

  try " We use the matching finally for cleaning up.
    if len(command_line) == command_index + 1 || (len(command_line) == command_index + 2 && a:ArgLead != "")
      " ************************** "
      " Complete the prime command "
      " ************************** "
      return "get\nkitchentext\nopen\nset\nwrite"
    endif

    if stridx("open", get(command_line, command_index + 1)) == 0 || (len(command_line) == command_index + 1 && a:ArgLead == command_name)
      " *************************** "
      " Complete the 'open' command "
      " *************************** "
      " ^ Note: the seconds part of the if rule above (the part after '||')
      " will eval to true whenever a filename matches our command name better
      " than the actually given command name (eg. ':C4 open C4c').
      if len(command_line) > command_index + 3 || (len(command_line) == command_index + 3 && a:ArgLead == "")
        " Do not return more than one file name.
        return ""
      endif
      let s:config_dir = s:FindConfigDir()
      if s:config_dir == ""
        return ""
      endif
      return join(map(glob(s:config_dir."*", 0, 1), "fnamemodify(v:val, ':t')"), "\n")

    elseif stridx("get", get(command_line, command_index + 1)) == 0
      " ************************** "
      " Complete the 'get' command "
      " ************************** "
      return ""

    elseif stridx("kitchentext", get(command_line, command_index + 1)) == 0
      " ********************************** "
      " Complete the 'kitchentext' command "
      " ********************************** "
      return ""

    elseif stridx("set", get(command_line, command_index + 1)) == 0
      " ************************** "
      " Complete the 'set' command "
      " ************************** "
      return "wohnzimmer\nplenarsaal\nfnordcenter\n-magic"

    elseif stridx("write", get(command_line, command_index + 1)) == 0 || (len(command_line) == command_index + 1 && a:ArgLead == command_name)
      " **************************** "
      " Complete the 'write' command "
      " **************************** "
      " ^ Note: the seconds part of the if rule above (the part after '||')
      " will eval to true whenever a filename matches our command name better
      " than the actually given command name (eg. ':C4 open C4c').
      if len(command_line) > command_index + 3 || (len(command_line) == command_index + 3 && a:ArgLead == "")
        " Do not return more than one file name.
        return ""
      endif
      let s:config_dir = s:FindConfigDir()
      if s:config_dir == ""
        return ""
      endif
      return join(map(glob(s:config_dir."*", 0, 1), "fnamemodify(v:val, ':t')"), "\n")

    else
      return ""
    endif

  finally
    unlet! s:config_dir
  endtry
endfunction " }}}1


" ************************************************************************** "
" Add our command to Vim.                                                    "
" ************************************************************************** "
if !exists(":C4ctrl") " {{{1
  command -nargs=+ -complete=custom,s:C4ctrlCompletion -range=% C4ctrl call C4ctrl(getcurpos(), <f-mods>, <line1>, <line2>, <f-args>)
endif " }}}1