#!/bin/sh

# Copyright (C) 2009 Modestas Vainius <modax@debian.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>
# Tag debian package release

info()
{
    echo "pkgkde-vcs: $*"
}

die()
{
    info "fatal: $*" >&2
    exit 1
}

# Determine VCS type of the repository in the current directory and echo
# its type to standard output.
# Supports Git at the moment
determine_vcs()
{
    # VCS might have been requested via program name
    local vcs
    vcs="`basename "$0"`"
    vcs="${vcs##pkgkde-}"
    case "$vcs" in
        vcs)
            if which git > /dev/null && git rev-parse --git-dir >/dev/null 2>/dev/null; then
                echo git
                return 0
            fi
            return 1
            ;;
        git)
            if which git > /dev/null; then
                echo "$vcs"
                return 0
            fi
            return 1
            ;;
        *)
            return 1
            ;;
    esac
}

# Determine LIBDIR. Supports both running in-source and installed
# version.
determine_libdir()
{
    local libdir
    libdir=`dirname $0 2>/dev/null`
    if [ -n "$libdir" ] && [ -d "$libdir/vcslib" ]; then
        echo "$libdir/vcslib"
        return 0
    else
        libdir="/usr/share/pkg-kde-tools/vcs"
        if [ -d "$libdir" ]; then
            echo "$libdir"
            return 0
        fi
    fi
    return 1
}

# Run the command prompting for confirmation if necessary
runcmd()
{
    local ans exitval
    if [ -n "$OPT_VERBOSE" ] || [ "$OPT_PROMPT" = "prompt" ]; then
        echo "$" "$*" >&2
    fi
    if [ "$OPT_PROMPT" = "prompt" ]; then
        echo -n "Run the command above and all others? (p = prompt next time) [Y/n/p]: "
        while true; do
            read ans
            if [ "$ans" = "Y" ] || [ "$ans" = "y" ] || [ -z "$ans" ]; then
                OPT_PROMPT="y"
                break
            elif [ "$ans" = "p" ] || [ "$ans" = "P" ]; then
                break;
            elif [ "$ans" = "N" ] || [ "$ans" = "n" ]; then
                info "Cancelled by user." >&2
                exit 2
            else
                echo -n "Enter Y (default) or N: "
            fi
        done
    fi

    if [ "$OPT_PROMPT" = "n" ]; then
        return 0
    fi

    # Run the command
    "$@"
    exitval="$?"
    if [ "$exitval" -eq "0" ]; then
        return 0
    else
        info "Command failed with $exitval" >&2
        exit $exitval
    fi
}

_get_deb_field()
{
    cat | grep "^$1:" | sed "s/^$1:[[:space:]]*\(.*\)\$/\1/"
}

# Given path to the package root (where debian/ subdirectory is), set some
# informational variables (DEB_* namespace) about the package
get_debian_package_info()
{
    local rootdir _pchangelog
    rootdir="$1"

    if [ -f "$rootdir/debian/changelog" ]; then
        _pchangelog="$(dpkg-parsechangelog "-l$rootdir/debian/changelog")"
        DEB_VERSION="$(echo "$_pchangelog" | _get_deb_field 'Version')"
        if [ -n "$DEB_VERSION" ]; then
            DEB_VERSION_WO_EPOCH=$(echo $DEB_VERSION | sed 's/^[[:digit:]]\+://')
        else
            die "unable to determine package version."
        fi
        DEB_SOURCE="$(echo "$_pchangelog" | _get_deb_field 'Source')"
        DEB_DISTRIBUTION="$(echo "$_pchangelog" | _get_deb_field 'Distribution')"
        DEB_URGENCY="$(echo "$_pchangelog" | _get_deb_field 'Urgency')"
    else
        die "debian/changelog could not be found in $rootdir"
    fi
}

is_valid_package_root()
{
    test -f "$1/debian/changelog" && test -f "$1/debian/control"
}

is_distribution_valid()
{
    local distro
    test -n "$1" || distro="$DEB_DISTRIBUTION"
    if [ "$(expr match "$distro" '^\(\(stable\|testing\)\(-security\|-proposed-updates\)\|\(squeeze\|wheezy\)-backports\|stable\|unstable\|experimental\)$')" = "$distro" ]; then
        return 0
    fi
    return 1
}

opt_till_double_dash() {
    local name
    # Parse out remaining -- if needed
    while getopts ":" name; do
        case "$name" in
            ?)  if [ -n "$OPTARG" ]; then OPTIND=$(($OPTIND-1)); fi; break;;
            :)  die "$OPTARG option is missing a required argument" ;;
        esac
    done
    if [ "$OPTIND" -gt 1 ]; then
        echo "$(($OPTIND-1))"
    else
        echo "0"
    fi
}

# Parse common options
OPT_VERBOSE=
OPT_PROMPT='prompt'

while getopts ":vyn" name; do
    case "$name" in
        v)  OPT_VERBOSE=1 ;;
        y)  OPT_PROMPT='y' ;;
        n)  OPT_PROMPT='n' ;;
        ?)  if [ -n "$OPTARG" ]; then OPTIND=$(($OPTIND-1)); fi; break;;
        :)  die "$OPTARG option is missing a required argument" ;;
    esac
done

if [ "$OPTIND" -gt 1 ]; then
    shift "$(($OPTIND-1))"
    OPTIND=1
fi

# Determine VCS type and source its library script

VCS=$(determine_vcs)
case "$VCS" in
    "")
        die "unable to determine VCS type or VCS tools (git, svn) are not installed."
        ;;
    *)
        # Load VCS script file. Determines LIBDIR in the process
        if LIBDIR=$(determine_libdir) && [ $? -eq 0 ]; then
            if [ -f "$LIBDIR/$VCS.sh" ]; then
                . "$LIBDIR/$VCS.sh"
            else
                die "$VCS VCS is NOT supported (via $LIBDIR)."
            fi
        else
            die "unable to determine pkgkde-vcs library directory."
        fi
        ;;
esac

exit 0