#!/bin/sh

#######
### restore mailcow from borgbackup repository
### this assumes three things:
###     1. standard mailcow-dockerized setup as per the docs
###     2. backups made using the backup script from this git repo
###     3. backups already downloaded from your borg repo
#######

### text-formatting presets
if command -v tput >/dev/null; then
    bold=$(tput bold)
    cyan=$(tput bold)$(tput setaf 6)
    err=$(tput bold)$(tput setaf 1)
    info=$(tput sgr0)
    magenta=$(tput sgr0)$(tput setaf 5)
    norm=$(tput sgr0)
    ok=$(tput setaf 2)
    width=$(tput cols)
    yellow=$(tput sgr0)$(tput setaf 3)
else
    bold=''
    cyan=''
    err=''
    info=''
    magenta=''
    norm=''
    ok=''
    width=80
    yellow=''
fi

### trap
trap trapExit 1 2 3 6

### functions

consoleError() {
    printf "\n%s%s\n" "$err" "$2"
    printf "Exiting.\n\n%s" "$norm"
    exit "$1"
}

exitError() {
    printf "%s[%s] --- %s execution completed with error ---\n%s" "$err" "$(stamp)" "$scriptName" "$norm" >>"$logfile"
    exit "$1"
}

scriptHelp() {
    textNewline
    printf "%sUsage: %s [parameters]%s\n\n" "$bold" "$scriptName" "$norm"
    textNewline
    textblock "If a parameter is not supplied, its default value will be used. Switch parameters will remain DEactivated if NOT specified."
    textNewline
    exit 0
}

stamp() {
    (date +%F' '%T)
}

textblock() {
    printf "%s\n" "$1" | fold -w "$width" -s
}

textblockHeader() {
    printf "\n%s%s***%s***%s\n" "$bold" "$magenta" "$1" "$norm"
}

textblockParam() {
    if [ -z "$2" ]; then
        # no default
        printf "%s%s%s\n" "$cyan" "$1" "$norm"
    else
        # default parameter provided
        printf "%s%s %s(%s)%s\n" "$cyan" "$1" "$yellow" "$2" "$norm"
    fi
}

textNewline() {
    printf "\n"
}

trapExit() {
    printf "%s[%s] -- [ERROR] 99: Caught signal --%s\n" "$err" "$(stamp)" "$norm" >>"$logfile"
    cleanup
    printf "%s[%s] --- %s execution terminated via signal ---\n%s" "$err" "$(stamp)" "$scriptName" "$norm" >>"$logfile"
    exit 99
}

writeLog() {
    if [ "$1" = "task" ]; then
        printf "%s[%s] -- [INFO] %s... " "$info" "$(stamp)" "$2" >>"$logfile"
    elif [ "$1" = "done" ]; then
        if [ -z "$2" ]; then
            printf "%sdone%s --\n%s" "$ok" "$info" "$norm" >>"$logfile"
        elif [ "$2" = "error" ]; then
            printf "%sERROR%s --\n%s" "$err" "$info" "$norm" >>"$logfile"
        elif [ "$2" = "warn" ]; then
            printf "%swarning%s --\n%s" "$yellow" "$info" "$norm" >>"$logfile"
        fi
    elif [ "$1" = "error" ]; then
        printf "%s[%s] -- [ERROR] %s: %s --\n%s" "$err" "$(stamp)" "$2" "$3" "$norm" >>"$logfile"
    elif [ "$1" = "warn" ]; then
        printf "%s[%s] -- [WARNING] %s --\n%s" "$yellow" "$(stamp)" "$2" "$norm" >>"$logfile"
    elif [ "$1" = "info" ]; then
        printf "%s[%s] -- [INFO] %s --\n%s" "$info" "$(stamp)" "$2" "$norm" >>"$logfile"
    elif [ "$1" = "success" ]; then
        printf "%s[%s] -- [SUCCESS] %s --\n%s" "$ok" "$(stamp)" "$2" "$norm" >>"$logfile"
    fi
}

### parameter defaults
# script related
scriptPath="$(CDPATH='' cd -- "$(dirname -- "$0")" && pwd -P)"
scriptName="$(basename "$0")"
errorCount=0
warnCount=0
backupLocation=""
sqlBackup=""
restoreMail=1
restoreSQL=1
restorePostfix=1
restoreRedis=1
restoreRspamd=1
verbose=0
# logfile default: same location and name as script but with '.log' extension
logfile="$scriptPath/${scriptName%.*}.log"
# mailcow/docker related
mcConfig='/opt/mailcow-dockerized/mailcow.conf'
mcDockerCompose='/opt/mailcow-dockerized/docker-compose.yml'
sqlRunning=0
dockerStartTimeout=180
dockerStopTimeout=120

### check if user is root
if [ "$(id -u)" -ne 0 ]; then
    consoleError '2' "This script must be run as ROOT."
fi

### process startup parameters
while [ $# -gt 0 ]; do
    case "$1" in
    -h|-\?|--help)
        # display help
        scriptHelp
        ;;
    -l|--log)
        # set logfile location
        if [ -z "$2" ]; then
            consoleError '1' "Log file path cannot be null. Leave unspecified to save log in the same directory as this script."
        fi
        logfile="$2"
        shift
        ;;
    -v|--verbose)
        verbose=1
        ;;
    -d|--docker-compose)
        # FULL path to docker-compose file
        if [ -n "$2" ]; then
            if [ -f "$2" ]; then
                mcDockerCompose="$2"
                shift
            else
                consoleError '1' "$1: cannot find docker-compose file as specified."
            fi
        else
            consoleError '1' "$1: cannot be blank/empty."
        fi
        ;;
    -m|--mailcow-config)
    # FULL path to mailcow configuration file file
        if [ -n "$2" ]; then
            if [ -f "$2" ]; then
                mcConfig="$2"
                shift
            else
                consoleError '1' "$1: cannot find mailcow configuration file as specified."
            fi
        else
            consoleError '1' "$1: cannot be blank/empty."
        fi
        ;;
    -t1|--timeout-start)
        if [ -z "$2" ]; then
            consoleError '1' "$1: cannot be blank/empty."
        else
            dockerStartTimeout="$2"
            shift
        fi
        ;;
    -t2|--timeout-stop)
        if [ -z "$2" ]; then
            consoleError '1' "$1: cannot be blank/empty."
        else
            dockerStopTimeout="$2"
            shift
        fi
        ;;
    -b|--backup-location)
        if [ -n "$2" ]; then
            if [ -d "$2" ] && [ -n "$( ls -A "$2" )" ]; then
                backupLocation="${2%/}"
                shift
            else
                consoleError '1' "$1: cannot find specified backup location directory or it is empty."
            fi
        else
            consoleError '1' "$1: cannot be blank/empty."
        fi
        ;;
    --skip-mail)
        restoreMail=0
        ;;
    --skip-sql)
        restoreSQL=0
        ;;
    --skip-postfix)
        restorePostfix=0
        ;;
    --skip-redis)
        restoreRedis=0
        ;;
    --skip-rspamd)
        restoreRspamd=0
        ;;
    *)
        printf "\n%sUnknown option: %s\n" "$err" "$1"
        printf "Use '--help' for valid options.%s\n\n" "$norm"
        exit 1
        ;;
    esac
    shift
done

### pre-flight checks
# set path so checks are valid for this script environment
export PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"

# docker installed?
if ! command -v docker >/dev/null; then
    consoleError '3' 'docker does not seem to be installed!'
fi
# mailcow.conf?
if [ ! -f "$mcConfig" ]; then
    consoleError '1' "mailcow configuration file ($mcConfig) cannot be found."
fi
# docker-compose configuration?
if [ ! -f "$mcDockerCompose" ]; then
    consoleError '1' "docker-compose configuration ($mcDockerCompose) cannot be found."
fi
# forgot to set backup location?
if [ -z "$backupLocation" ]; then
    consoleError '1' "'--backup-location' cannot be unspecified or null/empty."
fi
# change to mailcow directory so commands execute properly
\cd "${mcConfig%/*}" || consoleError '4' 'Cannot change to mailcow directory as determined from mailcow.conf location.'

### read mailcow.conf and import vars
# shellcheck source=./mailcow.conf.shellcheck
. "$mcConfig"
export COMPOSE_HTTP_TIMEOUT="$dockerStartTimeout"

### start logging
# verify logfile specification is valid
if ! printf "%s" "$logfile" | grep -o / >/dev/null; then
    # no slashes -> filename provided, save in scriptdir
    logfile="$scriptPath/$logfile"
elif [ "$(printf "%s" "$logfile" | tail -c 1)" = '/' ]; then
    # ends in '/' --> directory provided, does it exist?
    if [ ! -d "$logfile" ]; then
        if ! mkdir -p "$logfile" >/dev/null 2>&1; then
            consoleError '1' "Unable to make specified log file directory."
        fi
    fi
    logdir="$(cd "$logfile" 2>/dev/null && pwd -P)"
    logfile="${logdir}/${scriptName%.*}.log"
else
    # full path provided, does the parent directory exist?
    if [ ! -d "${logfile%/*}" ]; then
        # make parent path
        if ! mkdir -p "${logfile%/*}" >/dev/null 2>&1; then
            consoleError '1' "Unable to make specified log file path."
        fi
    fi
fi
# write initial log entries
if ! printf "%s[%s] --- Start %s execution ---\n%s" "$magenta" "$(stamp)" "$scriptName" "$norm" 2>/dev/null >>"$logfile"; then
    consoleError '1' "Unable to write to log file ($logfile)"
fi
writeLog 'info' "Log located at $logfile"

### get location of docker volumes
dockerVolumeMail=$(docker volume inspect -f '{{ .Mountpoint }}' ${COMPOSE_PROJECT_NAME}_vmail-vol-1)
writeLog 'info' "Using MAIL volume: ${dockerVolumeMail}"
dockerVolumeCrypt=$(docker volume inspect -f '{{ .Mountpoint }}' ${COMPOSE_PROJECT_NAME}_crypt-vol-1)
writeLog 'info' "Using MAILCRYPT volume: ${dockerVolumeCrypt}"
dockerVolumePostfix=$(docker volume inspect -f '{{ .Mountpoint }}' ${COMPOSE_PROJECT_NAME}_postfix-vol-1)
writeLog 'info' "Using POSTFIX volume: ${dockerVolumePostfix}"
dockerVolumeRedis=$(docker volume inspect -f '{{ .Mountpoint }}' ${COMPOSE_PROJECT_NAME}_redis-vol-1)
writeLog 'info' "Using REDIS volume: ${dockerVolumeRedis}"
dockerVolumeRspamd=$(docker volume inspect -f '{{ .Mountpoint }}' ${COMPOSE_PROJECT_NAME}_rspamd-vol-1)
writeLog 'info' "Using RSPAMD volume: ${dockerVolumeRspamd}"
# exit if mail or crypt containers cannot be found (mailcow not initialized beforehand)
if [ -z "$dockerVolumeMail" ] || [ -z "$dockerVolumeCrypt" ]; then
    writeLog 'error' '5' "Cannot find mail volume. Mailcow probably not initialized before running restore."
    exitError 5
fi

### restore SQL
if [ "$restoreSQL" -eq 1 ]; then
    writeLog 'task' "Restoring mailcow database"

    # sql restore pre-requisites
    sqlBackup=$(find "${backupLocation}/tmp" -iname "*.sql")
    if [ -n "$sqlBackup" ]; then
        # start mysql container if not already running
        if ! docker container inspect -f '{{ .State.Running }}' ${COMPOSE_PROJECT_NAME}_mysql-mailcow_1 > /dev/null 2>&1; then
            docker-compose up -d mysql-mailcow
            if docker container inspect -f '{{ .State.Running }}' ${COMPOSE_PROJECT_NAME}_mysql-mailcow_1 > /dev/null 2>&1; then
                sqlRunning=1
            else
                writeLog 'done' 'error'
                writeLog 'error' '12' "Cannot start mysql-mailcow container -- cannot restore mailcow database!"
                errorCount=$((errorCount+1))
            fi
        else
            sqlRunning=1
        fi
    else
        writeLog 'done' 'error'
        writeLog 'error' '11' "Cannot locate SQL backup -- cannot restore mailcow database!"
        errorCount=$((errorCount+1))
    fi

    # restore sql
    if [ "$sqlRunning" -eq 1 ]; then
        if docker exec -i "$(docker-compose ps -q mysql-mailcow)" mysql -u${DBUSER} -p${DBPASS} ${DBNAME} < "${sqlBackup}" > /dev/null 2>&1; then
            writeLog 'done'
        else
            writeLog 'done' 'error'
            writeLog 'error' '13' "Something went wrong while trying to restore SQL database. Perhaps try again?"
            errorCount=$((errorCount+1))
        fi
    fi
fi

#TODO: stop containers
#TODO: copy backups to correct docker volumes
#TODO: restart docker containers
#TODO: optionally reindex dovecot (parameter)

### exit gracefully
writeLog 'success' "All processes completed"
printf "%s[%s] --- %s execution completed ---\n%s" "$magenta" "$(stamp)" "$scriptName" "$norm" >>"$logfile"
# note non-terminating errors
if [ "$errorCount" -gt 0 ]; then
    printf "%s%s errors encountered!%s\n" "$err" "$errorCount" "$norm" >>"$logfile"
fi
# note warnings
if [ "$warnCount" -gt 0 ]; then
    printf "%s%s warnings issued!%s\n" "$yellow" "$warnCount" "$norm" >>"$logfile"
fi
exit 0

### error codes:
# 1: parameter error
# 2: not run as root
# 3: docker not installed
# 4: cannot change to mailcow directory
# 5: mailcow not initialized before running script
# 1x: SQL errors
#     11: cannot locate SQL dump in backup directory
#     12: cannot start mysql-mailcow container
#     13: restoring SQL dump was unsuccessful
# 99: TERM signal trapped
# 100: could not change to mailcow-dockerized directory
# 101: could not stop container(s)
# 102: could not start container(s)

#EOF