#!/bin/bash
#/**
#@file    importimage
#@usage   importimage [str_user] str_repo str_imagename
#@brief   Imports an image file from other repository
#@param   str_user      username to access the remote repository (local user, by default)
#@param   str_repo      repository IP address or hostaname
#@param   str_imagename image name to download
#@warning Program will request the repository REST token.
#@version 1.1.1 - Initial version
#@author  Ramón M. Gómez, ETSII Universidad de Sevilla
#@date    2018-10-08
#*/


# Variables.
PROG="$(basename "$0")"
OPENGNSYS="/opt/opengnsys"
REPODIR="$OPENGNSYS/images"
REPOCONF="$OPENGNSYS/etc/ogAdmRepo.cfg"
SERVERCONF="$OPENGNSYS/etc/ogAdmServer.cfg"
DEFAULTFILE="/etc/default/opengnsys"
MYCNF=$(mktemp /tmp/.my.cnf.XXXXX)
let BACKUP=0
source $DEFAULTFILE
source $REPOCONF &>/dev/null
[ "$RUN_OGADMSERVER" == "yes" ] && source $SERVERCONF &>/dev/null

# Functions.
source $OPENGNSYS/lib/ogfunctions.sh


# Main program.

# Error control.
[ "$USER" == "root" ] || raiseError access "Need to be root."
[ "$RUN_OGADMREPO" == "yes" ] || raiseError access "This server is not defined as image repository."
[ -w "$REPODIR" ] || raiseError access "Cannot write in local repository."
[ -n "$IPlocal" ] || raiseError access "Cannot read repository configuration file."
case $# in
    2)  USERNAME="$SUDO_USER"; REPO="$1"; IMAGE="$2" ;;
    3)  USERNAME="$1"; REPO="$2"; IMAGE="$3" ;;
    *)  [ "$*" == "help" ] && help || raiseError usage
esac
[ "${REPO,,}" == "${HOSTNAME,,}" ] || [ "${REPO,,}" == "localhost" ] || [[ ${REPO} =~ ^127\. ]] || [ "${REPO,,}" == "${IPlocal,,}" ] && raiseError access "Cannot import from local repository."

# Fetching image info from the repository.
read -rp "Enter repository API token: " APITOKEN
IMAGEINFO="$(curl -k -H "Authorization: $APITOKEN" "https://$REPO/opengnsys/rest/repository/image/$IMAGE" 2> /dev/null | jq -r .)"
IMAGENAME="$(jq -r '.name' <<< "$IMAGEINFO" 2>/dev/null)"
case "$IMAGEINFO" in
    "") # Connection error.
        raiseError access "Cannot connect to $REPO" ;;
    "[]") # Image not found.
        raiseError notfound "Image $IMAGE in remote repository $REPO" ;;
    *)  # Checking REST error.
        MESSAGE="$(jq -r '.message' <<< "$IMAGEINFO" 2>/dev/null)"
        [ -n "$MESSAGE" ] && raiseError access "$MESSAGE"
esac
IMAGETYPE="$(jq -r '.type' <<< "$IMAGEINFO" 2>/dev/null)"
IMAGELOCKED="$(jq -r '.locked' <<< "$IMAGEINFO" 2>/dev/null)"
[ "$IMAGELOCKED" == "true" ] && raiseError access "Image locked by remote repository."
IMAGESIZE="$(jq -r '.size' <<< "$IMAGEINFO" 2>/dev/null)"
[ -z "$IMAGESIZE" ] && raiseError access "Cannot retrieve image size"
# Checking if local image exists.
IMAGEPATH="$REPODIR/$IMAGENAME.$IMAGETYPE"
LOCKFILE="$IMAGEPATH.lock"
if [ -e "$IMAGEPATH" ]; then
    # Checking if local image is locked.
    [ -f "$LOCKFILE" ] && raiseError access "Local image is locked, cannot write."
    # Confirm image download.
    read -rp "Image $IMAGENAME exists in the local repository. Do you want to continue? (y/N): " ANSWER
    [ "${ANSWER,,}" = "y" ]  || exit
    BACKUP=1
    REMOTEDATE=$(jq -r '.modified' <<< "$IMAGEINFO" 2>/dev/null)
    LOCALDATE=$(stat -c "%y" "$IMAGEPATH" | cut -f1 -d.)
    if [[ "$REMOTEDATE" < "$LOCALDATE" ]]; then
        read -rp "Remote image seems older than the local one. Do you want to continue? (y/N): " ANSWER
        [ "${ANSWER,,}" = "y" ]  || exit
    fi
fi

# Trapping signal to unlock image before exit.
trap "rm -f $LOCKFILE $MYCNF" 1 2 3 6 9 15
# Creating lock file.
touch $LOCKFILE
# Backing up local image.
if [ $BACKUP -eq 1 ]; then
    mv -vf "$IMAGEPATH" "$IMAGEPATH.ant" 2>/dev/null
    mv -vf "$IMAGEPATH.torrent" "$IMAGEPATH.torrent.ant" 2>/dev/null
    mv -vf "$IMAGEPATH.sum" "$IMAGEPATH.sum.ant" 2>/dev/null
    mv -vf "$IMAGEPATH.full.sum" "$IMAGEPATH.full.sum.ant" 2>/dev/null
fi
# Downloading image file.
[[ $IMAGEPATH =~ / ]] && mkdir -p "$(dirname "$IMAGEPATH")"
scp "$USERNAME@$REPO:$IMAGEPATH" $REPODIR
ERRCODE=$?
if [ $ERRCODE -eq 0 ]; then
    # Cheking image size.
    DOWNLOADSIZE=$(stat -c "%s" "$IMAGEPATH")
    [ $IMAGESIZE -ne $DOWNLOADSIZE ] && echo "Warning: image sizes differ: source=$IMAGESIZE, target=$DOWNLOADSIZE."
    # Storing creation info.
    jq -r '.clonator+":"+.compressor+":"+.filesystem+":"+(.datasize|tostring)+":"' <<<"$IMAGEINFO" > "$IMAGEPATH.info"
    # Updating the database when the repo is also configured as Administration Server.
    if [ "$RUN_OGADMSERVER" == "yes" ]; then
        # Creating credentials file.
        cat << EOT > $MYCNF
[client]
user=$USUARIO
password=$PASSWORD
EOT
        if [ $BACKUP -eq 1 ]; then
            # If the image exists, increase its revision number.
            mysql --defaults-extra-file=$MYCNF -D "$CATALOG" -e \
                    "UPDATE imagenes
                        SET revision = revision + 1
                      WHERE nombreca='$IMAGE';" || \
                            echo "Warning: database cannot be updated."
	else
            # Obtaining defined Organizational Units.
            while read -re DATA; do 
                OUS[${#OUS[@]}]="$DATA" 
            done <<<$(mysql --defaults-extra-file=$MYCNF -D "$CATALOG" -Nse \
                              "SELECT idcentro, nombrecentro FROM centros;")
	    if [ ${#OUS[@]} -eq 1 ]; then
                # Only 1 OU is defined.
                let OUID="${OUS%% *}"
	    else
                # Choose image OU.
                echo "Choose Organization Unit:"
                PS3="Enter number: "
                select opt in "${OUS[@]#* }"; do
                    [ -n "$opt" ] && let OUID="${OUS[REPLY-1]%% *}" && break
                done
	    fi
            # Creating a new image associated with an empty software profile.
            mysql --defaults-extra-file=$MYCNF -D "$CATALOG" -e \
                    "SET @repoid = (SELECT idrepositorio FROM repositorios
                                     WHERE ip='$IPlocal' LIMIT 1),
                         @profname = '$IMAGE imported from $REPO';
                     INSERT INTO perfilessoft (descripcion, idcentro, grupoid)
                            SELECT @profname, '$OUID', 0 FROM DUAL
                             WHERE NOT EXISTS
                                   (SELECT descripcion FROM perfilessoft
                                     WHERE descripcion=@profname AND idcentro='$OUID')
                             LIMIT 1;
                     SET @profid = LAST_INSERT_ID();
                     INSERT INTO imagenes
                            (nombreca, revision, idperfilsoft, idcentro, comentarios, grupoid, idrepositorio, fechacreacion)
                     VALUES ('$IMAGE', 1, @profid, '$OUID', 'Image imported from repo $REPO', 0, @repoid, NOW());" || \
                            echo "Warning: database cannot be updated."
        fi
    fi
else
    # On download error, trying to recover backup.
    raiseError download "$USERNAME@$REPO:$IMAGEPATH"
    if [ $BACKUP -eq 1 ]; then
        mv -vf "$IMAGEPATH.ant" "$IMAGEPATH" 2>/dev/null
        mv -vf "$IMAGEPATH.torrent.ant" "$IMAGEPATH.torrent" 2>/dev/null
        mv -vf "$IMAGEPATH.sum.ant" "$IMAGEPATH.sum" 2>/dev/null
        mv -vf "$IMAGEPATH.full.sum.ant" "$IMAGEPATH.full.sum" 2>/dev/null
    fi
fi

# Unlocking image and removing temporary file.
rm -f $LOCKFILE $MYCNF