#autoload

# Complete the arguments of the current command according to the
# descriptions given as arguments to this function.

local long cmd="$words[1]" descr mesg subopts opt usecc autod
local oldcontext="$curcontext" hasopts multi ismulti

long=$argv[(I)--]
if (( long )); then
  local name tmp tmpargv

  if [[ long -eq 1 ]]; then
    tmpargv=()
  else
    tmpargv=( "${(@)argv[1,long-1]}" )
  fi

  name=${~words[1]}
  [[ "$name" = [^/]*/* ]] && name="$PWD/$name"

  name="_args_cache_${name}"
  name="${name//[^a-zA-Z0-9_]/_}"

  if (( ! ${(P)+name} )); then
    local iopts sopts pattern tmpo cur cache
    typeset -U lopts

    cache=()

    # We have to build a new long-option cache, get the `-i' and
    # `-s' options.

    set -- "${(@)argv[long+1,-1]}"

    iopts=()
    sopts=()
    while [[ "$1" = -[is]* ]]; do
      if [[ "$1" = -??* ]]; then
        tmp="${1[3,-1]}"
        cur=1
      else
        tmp="$2"
	cur=2
      fi
      if [[ "$tmp[1]" = '(' ]]; then
	tmp=( ${=tmp[2,-2]} )
      else
	tmp=( "${(@P)tmp}" )
      fi
      if [[ "$1" = -i* ]]; then
        iopts=( "$iopts[@]" "$tmp[@]" )
      else
        sopts=( "$sopts[@]" "$tmp[@]" )
      fi
      shift cur
    done

    # Now get the long option names by calling the command with `--help'.
    # The parameter expansion trickery first gets the lines as separate
    # array elements. Then we select all lines whose first non-blank
    # character is a hyphen. Since some commands document more than one
    # option per line, separated by commas, we convert commas into
    # newlines and then split the result again at newlines after joining 
    # the old array elements with newlines between them. Then we select
    # those elements that start with two hyphens, remove anything up to
    # those hyphens and anything from the space or tab after the
    # option up to the end.

    lopts=("--${(@)^${(@)${(@)${(@M)${(@ps:\n:j:\n:)${(@)${(@M)${(@f)$(_call options ${~words[1]} --help 2>&1)//\[--/
--}:#[ 	]#-*}//,/
}}:#[ 	]#--*}#*--}%%[]	 ]*}:#}")
    lopts=( "${(@)lopts:#--}" )

    # Now remove all ignored options ...

    while (( $#iopts )); do
      lopts=( ${lopts:#$~iopts[1]} )
      shift iopts
    done

    # ... and add "same" options

    while (( $#sopts )); do
      lopts=( $lopts ${lopts/$~sopts[1]/$sopts[2]} )
      shift 2 sopts
    done

    # Then we walk through the descriptions plus a few builtin ones.

    set -- "$@" '*=FILE*:file:_files' \
           '*=(DIR|PATH)*:directory:_files -/' '*: :'

    while (( $# )); do

      # First, we get the pattern and the action to use and take them
      # from the positional parameters.

      pattern="${${${(M)1#*[^\\]:}[1,-2]}//\\\\:/:}"
      descr="${1#${pattern}}"
      shift

      # We get all options matching the pattern and take them from the
      # list we have built. If no option matches the pattern, we
      # continue with the next.

      tmp=("${(@M)lopts:##$~pattern}")
      lopts=("${(@)lopts:##$~pattern}")

      (( $#tmp )) || continue

      opt=''

      # If there are option strings with a `[=', we take these get an
      # optional argument.

      tmpo=("${(@M)tmp:#*\[\=*}")
      if (( $#tmpo )); then
        tmp=("${(@)tmp:#*\[\=*}")
        tmpo=("${(@)${(@)tmpo%%\=*}//[^a-z0-9-]}")

        if [[ "$descr" = ::* ]]; then
	  cache=( "$cache[@]" "${(@)^tmpo}=${descr}" )
        else
	  cache=( "$cache[@]" "${(@)^tmpo}=:${descr}" )
        fi
      fi

      # Descriptions with `=': mandatory argument.

      tmpo=("${(@M)tmp:#*\=*}")
      if (( $#tmpo )); then
        tmp=("${(@)tmp:#*\=*}")
        tmpo=("${(@)${(@)tmpo%%\=*}//[^a-z0-9-]}")

	cache=( "$cache[@]" "${(@)^tmpo}=${descr}" )
      fi

      # Everything else is just added as a option without arguments.

      if (( $#tmp )); then
        tmp=("${(@)tmp//[^a-zA-Z0-9-]}")
	cache=( "$cache[@]" "$tmp[@]" )
      fi
    done
    eval "${name}=( \"\${(@)cache:# #}\" )"
  fi
  set -- "$tmpargv[@]" "${(@P)name}"
fi

multi=(-i)
subopts=()
while [[ "$1" = -(O*|C|M*) ]]; do
  case "$1" in
  -C) usecc=yes; shift ;;
  -O) subopts=( "${(@P)2}" ); shift 2 ;;
  -O*)  subopts=( "${(@P)1[3,-1]}" ); shift ;;
  -M) ismulti=yes multi=(-I "$2" "$3"); shift 3 ;;
  -M*) ismulti=yes multi=(-I "${1[3,-1]}" "$2"); shift 2 ;;
  esac
done

zstyle -s ":completion:${curcontext}:options" auto-description autod

if (( $# )) && comparguments "$multi[@]" "$autod" "$@"; then
  local nm="$compstate[nmatches]" action noargs aret expl local
  local next direct odirect equal single match matched ws tmp1 tmp2 tmp3
  local opts subc tc prefix suffix descrs actions subcs
  local origpre="$PREFIX" origipre="$IPREFIX"

  if comparguments -D descrs actions subcs; then
    if comparguments -O next direct odirect equal; then
      opts=yes
      _tags "$subcs[@]" options
    else
      _tags "$subcs[@]"
    fi
  else
    if comparguments -a; then
      noargs='no more arguments'
      had_args=yes
    else
      noargs='no arguments'
    fi
    comparguments -O next direct odirect equal || return 1

    opts=yes
    _tags options
  fi

  context=()
  state=()

  while true; do
    while _tags; do
      while (( $#descrs )); do

	action="$actions[1]"
	descr="$descrs[1]"
	subc="$subcs[1]"

        if [[ -n "$matched" ]] || _requested "$subc"; then

          curcontext="${oldcontext%:*}:$subc"

          _description "$subc" expl "$descr"

          if [[ "$action" = \=\ * ]]; then
            action="$action[3,-1]"
            words=( "$subc" "$words[@]" )
	    (( CURRENT++ ))
          fi

          if [[ "$action" = -\>* ]]; then
            comparguments -W line opt_args
            state=( "$state[@]" "${${action[3,-1]##[ 	]#}%%[ 	]#}" )
	    if [[ -n "$usecc" ]]; then
	      curcontext="${oldcontext%:*}:$subc"
	    else
	      context=( "$context[@]" "$subc" )
	    fi
            compstate[restore]=''
            aret=yes
          else
            if [[ -z "$local" ]]; then
              local line
              typeset -A opt_args
              local=yes
            fi

            comparguments -W line opt_args

            if [[ "$action" = \ # ]]; then

              # An empty action means that we should just display a message.

              [[ -n "$matched" ]] &&
                  compadd -n -Q -S '' -s "$SUFFIX" - "$PREFIX"
              mesg="$descr"

            elif [[ "$action" = \(\(*\)\) ]]; then

              # ((...)) contains literal strings with descriptions.

              eval ws\=\( "${action[3,-3]}" \)

              _describe -t "$subc" "$descr" ws -M "$match" "$subopts[@]"

            elif [[ "$action" = \(*\) ]]; then

              # Anything inside `(...)' is added directly.

              _all_labels "$subc" expl "$descr" \
                  compadd "$subopts[@]" - ${=action[2,-2]}
            elif [[ "$action" = \{*\} ]]; then

              # A string in braces is evaluated.

              while _next_label "$subc" expl "$descr"; do
                eval "$action[2,-2]"
              done
            elif [[ "$action" = \ * ]]; then

              # If the action starts with a space, we just call it.

	      eval "action=( $action )"
              while _next_label "$subc" expl "$descr"; do
                "$action[@]"
              done
            else

              # Otherwise we call it with the description-arguments.

              eval "action=( $action )"
              while _next_label "$subc" expl "$descr"; do
                "$action[1]" "$subopts[@]" "$expl[@]" "${(@)action[2,-1]}"
	      done
            fi
          fi
        fi
        shift 1 descrs
        shift 1 actions
        shift 1 subcs
      done

      if [[ -z "$matched$hasopts" ]] && _requested options &&
          { ! zstyle -T ":completion:${curcontext}:options" prefix-needed ||
            [[ "$origpre" = [-+]* ||
            ( -z "$aret$mesg" && nm -eq compstate[nmatches] ) ]] } ; then
	local prevpre="$PREFIX" previpre="$IPREFIX"

	hasopts=yes

	PREFIX="$origpre"
	IPREFIX="$origipre"

        comparguments -M match
	
        if comparguments -s single; then

          if [[ "$single" = direct ]]; then
            _all_labels options expl option \
	        compadd -QS '' - "${PREFIX}${SUFFIX}"
          elif [[ "$single" = next ]]; then
            _all_labels options expl option \
	        compadd -Q - "${PREFIX}${SUFFIX}"
          elif [[ "$single" = equal ]]; then
            _all_labels options expl option \
	        compadd -QqS= - "${PREFIX}${SUFFIX}"
          else
	    tmp1=( "$next[@]" "$direct[@]" "$odirect[@]" "$equal[@]" )
	    tmp3=( "${(M@)tmp1:#[-+]?[^:]*}" )
	    tmp1=( "${(M@)tmp1:#[-+]?(|:*)}" )
	    tmp2=( "${PREFIX}${(@M)^${(@)${(@)tmp1%%:*}#[-+]}:#?}" )

            _describe -o option \
                      tmp1 tmp2 -Q -S '' -- \
		      tmp3 -Q
          fi
          single=yes
        else
          next=( "$next[@]" "$odirect[@]" )
          _describe -o option \
            next -Q -M "$match" -- \
            direct -QS '' -M "$match" -- \
            equal -QqS= -M "$match"
        fi
	PREFIX="$prevpre"
	IPREFIX="$previpre"
      fi
    done
    if [[ -n "$opts" && -z "$aret$matched$mesg" &&
          nm -eq compstate[nmatches] ]]; then

      PREFIX="$origpre"
      IPREFIX="$origipre"

      prefix="${PREFIX#*\=}"
      suffix="$SUFFIX"
      PREFIX="${PREFIX%%\=*}"
      SUFFIX=''
      compadd -M "$match" -D equal - "${(@)equal%%:*}"

      if [[ $#equal -eq 1 ]]; then
        PREFIX="$prefix"
	SUFFIX="$suffix"
	IPREFIX="${IPREFIX}${equal[1]%%:*}="
	matched=yes

	comparguments -L "${equal[1]%%:*}" descrs actions subcs

	_tags "$subcs[@]"

	continue
      fi
    fi
    break
  done

  [[ -z "$aret" || -z "$usecc" ]] && curcontext="$oldcontext"

  [[ -n "$aret" ]] && return 300

  [[ -n "$mesg" ]] && _message "$mesg"
  if [[ -n "$noargs" ]]; then
    [[ -z "$ismulti" && nm -eq "$compstate[nmatches]" ]] && _message "$noargs"
  else
    has_args=yes
  fi

  # Set the return value.

  [[ nm -ne "$compstate[nmatches]" ]]
else
  return 1
fi