#!/bin/bash

advi_texdir='@ADVI_TEXDIR@'
texdir='@TEXDIR@'
latexdir='@LATEXDIR@'
advi_latexdir=${advi_texdir}/tex/latex
dest=${latexdir}/advi

cmd=advi-latex-files


warn () {
    echo "$@" 1>&2; 
}

error () {
    case $# in 0) ;; *) warn "$@";; esac
    exit 1
}

usage () {
    cat<<EOF
Usage:
    ${cmd} --install help
    ${cmd} --install default
    ${cmd} --install <DESTPATH>
    ${cmd} --uninstall
    ${cmd} --list
    ${cmd} --path
EOF
    error
}

help () {
    cat <<EOF
Usage:

        ${cmd} --install <DESTPATH>

 - If <DESTPATH> is equal to "help", print this message.

 - If <DESTPATH> is equal to "default", this will attempt to find
   the default path for latex style files in your latex distribution
   hierarchy and install the files there.

   This command must then probably be run as root.
   You may actually need to provide the full path:

        sudo $(which ${cmd}) --install default

 - Otherwise, <DESTPATH> must be a valid directory. 

   This will attempt to install the files in this directory, which should
   exist and be writable.

   You then must ensure that <DESTPATH> is included in your latex source
   path environment variable "TEXINPUTS". You may also have to run

        mktexlsr

   manually to rebuild filename databases used by TeX.

EOF
    exit 0
    }

case $# in 1) ;; 2) ;; *) usage; esac
command="$1"
path="$2"

case "${command}" in
    --install)
        case "${path}" in
            ""|help) help ;;
            default) ;;
            /*) dest="${path}";;
            *) error 'You give a full path' ;;
        esac
        ;;
    --uninstall)
        case $# in 2) usage;; esac
        if test "${latexdir}" = undefined
        then
            error 'Unknown installation directory: cannot uninstall.'
        fi
        ;;
    --list)
        ls "${advi_latexdir}"
        exit 0
        ;;
    --path)
        echo "${advi_latexdir}"
        exit 0
        ;;
    *) usage
       ;;
esac


install-message () {
    echo 'Latex files, which are currently in:'
    echo
    echo '    ' "${advi_latexdir}/"
    echo
    echo 'will be installed in the repository'
    echo
    echo '    ' "${dest}/"
    echo
    echo "See ${cmd} -help to see how to choose another path"
    echo 'You may also manually copy the files in some other location'
    echo 'in your TEXINPUTS path.'
    echo
}

installed () {
    if test ! -r ${dest}
    then
        echo "No files installed in ${dest}"
        exit 1;
    fi
}

check () {
    if test ! -x ${latexdir}
    then
        warn "Destination ${latexdir} does not exits."
        error "Tou must create it first."
    fi

    if test ! -w ${latexdir}
    then
        warn "Destination ${latexdir} is not writable"
        error 'This script must be run as root.'
    fi

    read -p 'Continue [yes/no] ' answer

    case ${answer} in
        yes) echo 'Proceeding...' ;;
        *) echo Aborted; exit 1 ;;
    esac
}

doinstall () {    
    echo "install ${advi_latexdir}/* ${dest}" && \
        install -d ${dest}/ && \
        install ${advi_latexdir}/* ${dest}/ && \
        echo mktexlsr && \
        mktexlsr && \
        echo Done || error 'An error occured'
}

uninstall-message () {
    echo 'This is going to uninstall latex files ecurrently in the distribution repository'
    echo
    echo '    ' "${dest}/"
    echo
    echo 'You may also do this manually.'
    echo
}

douninstall () {
    for i in $(cd ${dest} && ls)
    do
        rm -v ${dest}/$i
    done && 
    rmdir ${dest} &&
    mktexlsr
}

case ${command} in
     --install)
          install-message && check && doinstall ;;
     --uninstall) 
          installed && uninstall-message && check && douninstall ;;
esac
