#!/bin/sh

# lazy config
_sqlports="/usr/local/share/sqlports"
_pkgpath="$(head -1 /etc/installurl)/$(uname -r)/packages/$(uname -m)"

# parameters can be freely combined
_usage() {
    echo "usage: pkg-depends [options] <pkgpath>"
    echo "options: -r       - list run dependencies (default)"
    echo "         -l       - list lib dependencies (default)"
    echo "         -b       - list build dependencies"
    echo "         -t       - list test dependencies"
    echo "         -p       - show packges names (default)"
    echo "         -P       - show port paths"
    echo "         -d <dir> - download packages to <dir>"
    echo
    echo "Only one flavor / subpackage in pkgpath(7) is supported."
    exit 2
}

while getopts rlbtpPd: arg
do
    case $arg in
        l)      _deps="$_deps 0" ;;
        r)      _deps="$_deps 1" ;;
        b)      _deps="$_deps 2" ;;
        t)      _deps="$_deps 3" ;;
        p)      _showmode=$(( _showmode + 1 )) ;;
        P)      _showmode=$(( _showmode + 2 )) ;;
        d)      _dldir=$OPTARG ;;
        h)      _usage ;;
        ?)      _usage ;;
    esac
done
shift $(($OPTIND - 1))

[ -z "$1" ] \
    && _usage

if [ ! -f "$_sqlports" ]
then
    echo "$_sqlports not found. Install \"sqlports\" to use this script."
    exit 1
fi

### FUNCTIONS

# a little helper in case no pkgpath is provided
_do_pkg() {
    echo "pkg-depends needs pkgpath(7) as argument, pkg_info -P can help."
    echo "Here, I'm calling it for you:"
    echo
    echo "$ pkg_info -P $1"
    pkg_info -P "$1"
    exit 0
}

_do_sql() {

    # XXX: This lists all dependencies for the dependencies for the
    # dependencies. I haven't encountert an endless loop here (yet?).
    # I guess sqlite takes care or that?
    # I'm sure the performance can be improved by not using the big
    # ports view to grab the pkgname. But it's late and it works and
    # this is a problem for another day.
    _query="
    WITH RECURSIVE pkg(x) AS (
        SELECT \"$1\"
        UNION
        SELECT distinct dependspath FROM canonical_depends
        JOIN pkg ON fullpkgpath=x WHERE type in ($2)
    ) SELECT x, fullpkgname FROM pkg
      JOIN ports ON fullpkgpath=x;
    "
    echo "SQL QUERY: $_query" > $HOME/pkg-depends.log
    echo "RESULT:" >> $HOME/pkg-depends.log
    sqlite3 "$_sqlports" "$_query" | tee -a $HOME/pkg-depends.log
}

_handle_list() {
    # build the comma sparated list that descibes the types
    # to include in the list. Used in the sql query.
    # _deps are set in getops, with a leading space when 0
    # is not set. FIXME: I'm sure there's a better way to do this.
    if [ -z "$_deps" ]
    then
        _deps="0,1"
    else
        _deps="$(echo "$_deps" \
                    | tr -s " " \
                    | sed 's/^ //g' \
                    | tr ' ' ',')"
    fi

    # download mode: create directory provided in -d <dir>
    if [ -n "$_dldir" ]
    then
        mkdir -p "$_dldir"
    fi

    echo "Figuring out recursive dependencies, this may take some time..."
    # FIXME: even though the list ist sorted -u this is only true for 
    # pkgpath, as textproc/libical and textproc/libical,-main are the
    # going to be the same package. Simply stripping off all ,-main
    # could fix it.. but it doesn't feel right.
    _do_sql "$1" "$_deps" | sort -u | while read line
    do
        _portpath=$(echo "$line" | cut -d"|" -f1)
        _pkgname=$(echo "$line" | cut -d"|" -f2)

        # download mode: -d <dir>
        if [ -n "$_dldir" ]
        then
            _extra="(downloading)"
        fi

        # showmode:
        # unset: shows pkgpath and pkgname
        # 1: shows pkgname only
        # 2: shows pkgpath only
        # 3: equals unset # FIXME: set 3 as default and don't handle unset.
        # default || both on
        if [ -z "$_showmode" ] || [ "$_showmode" == "3" ]
        then
            echo "$_portpath ($_pkgname) $_extra"
        fi
        # pkgname only
        if [ "$_showmode" == "1" ]
        then
            echo "$_pkgname $_extra"
        fi
        # portpath only
        if [ "$_showmode" == "2" ]
        then
            echo "$_portpath $_extra"
        fi

        # download mode: download file from mirror
        # note: this needs sqlports information and the mirror to be
        # in sync, which only the case on -release.
        # FIXME: figure out a way to do this in snaps.
        # Naive idea: cut off the version, get index list from mirror with
        # match agains the non-version name and download everything found.
        if [ -n "$_dldir" ]
        then
            ftp -MV -C -o $_dldir/$_pkgname.tgz $_pkgpath/$_pkgname.tgz
        fi
    done

    if [ -n "$_dldir" ]
    then
        # XXX: Are both variables needed?
        echo "Set the following environmane variables to enable offline installation:"
        echo "$ export TRUSTED_PKG_PATH=\"$(readlink -f "$_dldir")\""
        echo "$ export PKG_PATH=\"$(readlink -f "$_dldir")\""
        # FIXME: name the package that has been downloaded. But to translate $1
        # to the package name, another sqlports db call would be necessary.
        # There is also pkg_info -e ..., but that only works for alread installed
        # packages.
        echo "$ pkg_add <package>"
    fi
}

### MAIN PROGRAM :)
case "$1" in
    */*) _handle_list "$1" ;;
      *) _do_pkg "$1" ;;
esac