#!/bin/ksh
#
########################################################################
#
# snaps.sh - Check if you can upgrade your OpenBSD OS base to
# last -current snapshot
#
# Copyright (c) 2017-2020, Fred Galusik <f AT galusik.fr>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# 3. Neither the name of the copyright holder nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
########################################################################

###
### VARS
###

VERSION=1.3

# choose your MIRROR
if [ ! "${MIRROR}" ]; then
    MIRROR=$(grep -v "^#" /etc/installurl)
fi

# curl is mandatory
CURL=/usr/local/bin/curl
if [[ ! -e ${CURL} ]]; then
    echo "{CURL} is requested to run this program. Aborting..."
    exit 1
fi

# 
CURRENTSYS=$(sed 1q /var/run/dmesg.boot)
ARCH=$(uname -m)
BASE=/snapshots/${ARCH}/
PACKAGES=/snapshots/packages/${ARCH}/

MIRRORB=${MIRROR}/snapshots/${ARCH}/
MIRRORPKG=${MIRROR}/snapshots/packages/${ARCH}/
HTTPSLIST=https://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/www/httpslist

SHAF=SHA256

GET='ftp -n -m -C'

LOGF=/var/log/snaps.log
NOW=$(date "+ %Y-%m-%d %R")

REMOTESNAPS='https://framagit.org/fredg/snaps/raw/master/snaps'
LASTSNAPS=/tmp/snaps

###
###
###


usage() {
    echo "${0##*/} $VERSION"
    echo "Usage: ${0##*/} [-scpluh]"
    echo ""
    echo "  -s  check \$MIRROR freshness & choose to sysupgrade or not"
    echo "  -c  check BASE and PACKAGES build date from \$MIRROR"
    echo "  -p  update port tree to -current"
    echo "  -l  list date and \$MIRROR of the 3 last upgrade with this script"
    echo "  -u  upgrade snaps to last version"
    echo "  -h  print this help and exit"
    echo ""
    echo "MIRROR is based upon /etc/installurl and set to: $MIRROR"
    echo ""
    echo "You can set it manually:"
    echo "\$ MIRROR=http://mirrors.ircam.fr/pub/OpenBSD snaps -c"
    echo ""
}


s_root() {
    if [[ $(id -u) != "0" ]]; then
        echo "WARNING: You need to be root to do this!" 1>&2
        exit 1
    fi
}


toupgrade() {
    echo "Checking snaps release..."
    if [[ -f "$LASTSNAPS" ]]; then
      rm -f $LASTSNAPS
    fi
    if $GET -V -o "$LASTSNAPS" "$REMOTESNAPS"; then
        REMOTEVERSION=$(awk -F '=' '/^VERSION=/ { print $2 }' "$LASTSNAPS")
        if [ "$VERSION" != "$REMOTEVERSION" ]; then
            echo "WARNING: snaps is not up-to-date !"
            echo "Last version: $REMOTEVERSION"
            echo "To upgrade, run 'snaps -u'"
        else
            echo "GOOD: snaps is up-to-date."
        fi
    else
          echo "WARNING: Remote snaps not reachable ! Check the connection."
    fi
    echo ""
}


upgrade() {
    SELFPATH=$(dirname "$(readlink -f -- "$0")")
    echo "Downloading last snaps version..."
    $GET -o "$SELFPATH" "$REMOTESNAPS"
}


get_log() {
    if [[ -f "$LOGF" ]]; then
        tail -n 3 $LOGF
    else
        echo "No $LOGF file. Seems you have not yet played with snaps."
        exit 1
    fi
}


s_upports() {
    echo "Updating Ports tree..."
    cd /usr/ports || exit 1
    cvs up -Pd || exit 1
    echo "New Ports tree fetched!"
}


s_cur() {
    echo "=== LOCAL BASE BUILD DATE ==="
    echo "${CURRENTSYS}"
}


s_when() {
    CURLB="$(${CURL} -sI "${MIRRORB}${SHAF}" | grep Last-Modified)"
    CURLP="$(${CURL} -sI "${MIRRORPKG}${SHAF}" | grep Last-Modified)"
    echo "=== ONLINE BASE AND PACKAGES BUILD DATE ==="
    echo "From ${MIRROR}"
    echo "Base (${ARCH})     => ${CURLB}"
    echo "Packages (${ARCH}) => ${CURLP}"
}


s_sysup () {
    echo ""
    echo -n "Do you want to run 'sysupgrade -s' ? (y/n): "
    read -r _c
    case ${_c} in
        y|Y)
            ;;
        *)
            echo "Aborting..."
            exit 1
            ;;
    esac
    echo "${NOW} FROM ${MIRRORB}" >> ${LOGF}
    sysupgrade -s
}


all_mirrors () {
    MIRRORLIST=$(${CURL} ${HTTPSLIST} | awk '{print $1}')
    for _m in ${MIRRORLIST}
    do
        CB="$(${CURL} -sI "${_m}${BASE}${SHAF}" | grep Last-Modified |\
            sed 's/Last-Modified: //')"
        CP="$(${CURL} -sI "${_m}${PACKAGES}${SHAF}" | grep Last-Modified |\
            sed 's/Last-Modified: //')"
        # only print mirror which give an answer
        # FIXME try to figure out how to print 1 mirror per line
        if [ "${CB}" ]; then
            echo "${_m}"
            echo "${CB}"
            echo "${CP}"
            echo ""
        fi
    done
}


##
## Run
##

case $1 in
    -s)
        s_root
        toupgrade
        s_cur
        echo ""
        s_when
        s_sysup
        ;;
    -c)
        s_when
        ;;
    -a)
        all_mirrors
        ;;
    -p)
        s_upports
        ;;
    -l)
        get_log
        ;;
    -u)
        upgrade
        ;;
    -h|*)
        usage
        exit 1
        ;;
esac