cabal command line completion

cabal

# cabal command line completion
# Copyright 2014 "Osman Veliev" <ocmanv@gmail.com>
#
# Реализовано:
# - кеширование списка пакетов - _cabal_cach()
# - автодополнение версии пакета
# - напоминания об устаревшей базе пакетов - _cabal_log()
# - и установленных версиях пакета - _cabal_installed()
# - автодополнение для "cabal list"

# Input: $@
# Output: STDERR
_cabal_echo()
{
    if [[ "$1" != "" ]]; then
        echo >&2
        for i in "$@" ; do
            echo "$i" >&2
        done
        kill -SIGWINCH $$
    fi
}

# Input: STDIN
# Output: STDERR
_cabal_log()
{
    local IFS=$'\n'
    read -t 10 -a line
    while read -t 2 ln ; do
        line+=("${ln[*]}")
    done
    _cabal_echo "${line[@]}"
}

# Input: $1
# Output: STDERR
_cabal_installed()
{
    local name="$1"
    local message=( )
    for db in global user ; do
        local a="$( ghc-pkg --simple-output --$db list | sed 'y:\ :\n:' | grep -E "^${name}-([.0-9]+)$" )"
        [[ "$a" ]] && message+=("Warning: Installed in $db DB: $a")
    done
    _cabal_echo "${message[*]}"
}

# Input: $cur $cach
# Output: $COMPREPLY
_cabal_packages()
{
    local name vers ver
    if [[ ${cur} =~ ^(([^.-]+-)+)([.0-9]+)?$ ]]; then
        name="${BASH_REMATCH[1]%-}"
        ver="${BASH_REMATCH[3]}"
        vers=( $( cat "$cach" | grep -E "^${name} " ) )
    fi

    if [[ "$vers" ]]; then
        _cabal_installed "${name}"
#        [[ "${COMP_WORDBREAKS}" != *-* ]] && export COMP_WORDBREAKS+=-
#        COMPREPLY=( $( compgen -W "${vers[*]:1}" -- "$ver" ) )
        COMPREPLY=( $( compgen -P "${name}-" -W "${vers[*]:1}" -- "$ver" ) )
    else
#        export COMP_WORDBREAKS="${COMP_WORDBREAKS//-}"
        COMPREPLY=( $( compgen -W "$( cat ${cach} | cut -d' ' -f1 )" -- "$cur" ) )
    fi
}

# Input: $cach
# Output: STDERR file://"$cach"
_cabal_cach()
{
    local path="$HOME/.cabal/packages/hackage.haskell.org"
    local f="$path/00-index.cache"
    local cmd="${words[0]} list --simple-output"

    if [[ "$f" -nt "$cach" ]]; then
        touch "$cach"
        (
            _cabal_echo "Caching..."
            ( $cmd | sed -rn ':a $!N; s:^(.*)( .*)\n\1( .*)$:\1\2\3:; ta; P; D' >"$cach" ) 2>&1 | _cabal_log
            _cabal_echo "Cached"
        ) & >&- <&-
    fi
}

_cabal()
{
#    export COMP_WORDBREAKS="${COMP_WORDBREAKS//-}"

    local cur words cword
    _get_comp_words_by_ref -n - cur words cword

    local cach="/tmp/bash-completion-cabal"
    _cabal_cach

    local left="${words[*]:1:(($cword-1))}"

    if [[ "$cur" != -* && " ${left} " =~ \ (install|list|info|fetch|get)\  ]]; then
        if [[ ${BASH_REMATCH[1]} == list ]]; then
            COMPREPLY=( $( cat ${cach} | cut -d' ' -f1 | grep -i "$cur" ) )
        else
            _cabal_packages
        fi
    else
        local cmd=( ${words[@]} )
        cmd[${cword}]="--list-options"
        COMPREPLY=( $( compgen -W "$( ${cmd[@]} )" -- $cur ) )
    fi
}

complete -F _cabal -o default cabal