#!/bin/bash
set -uo pipefail
IFS=$'\n\t'

PATH="/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin"
SCRIPT_NAME=$(basename "$0")
LOGFILE="/var/log/${SCRIPT_NAME%.sh}.log"

log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] $*" | tee -a "$LOGFILE"
}

usage() {
    echo "Usage:"
    echo "  $0 -c /path/to/config                 # Full backup run"
    echo "  $0 [function]                         # Run individual function"
    echo "  $0 help                               # Show available functions"
    exit 1
}

CONFIG_FILE=""
while getopts "c:" opt; do
    case "$opt" in
        c) CONFIG_FILE="$OPTARG" ;;
        *) usage ;;
    esac
done

# Bei Einzelaufruf muss Konfiguration geladen sein
shift $((OPTIND - 1))

if [[ -n "${CONFIG_FILE:-}" ]]; then
    if [[ ! -f "$CONFIG_FILE" ]]; then
        log "ERROR: Configuration file not found: $CONFIG_FILE"
        exit 1
    fi

if ! bash -n "$CONFIG_FILE"; then
    log "Syntaxfehler in Konfigurationsdatei $CONFIG_FILE"
    exit 1
fi

    source "$CONFIG_FILE"

    # ==========================
    # Konfigurationsprüfung
    # ==========================
    REQUIRED_VARS=(
        SSHPORT
        BACKUPSERVER
        ZSYNC
        MAINTDAY
        SHUTDOWN
        UPDATES
        SOURCEHOST
        ZFSROOT
        ZFSSECOND
        ZFSTRGT
        ZPUSHTAG
        ZPUSHMINKEEP
        ZPUSHKEEP
        ZPUSHLABEL
        ZPUSHFILTER
        PBSHOST
        BACKUPSTORE
        BACKUPSTOREPBS
        BACKUPEXCLUDE
        REPLEXCLUDE
    )

    MISSING_VARS=()
    for var in "${REQUIRED_VARS[@]}"; do
        #if [[ -z "${!var:-}" ]]; then
        if ! declare -p "$var" &>/dev/null || [[ -z "${!var}" ]]; then
            MISSING_VARS+=("$var")
        fi
    done

    if [[ "${#MISSING_VARS[@]}" -ne 0 ]]; then
        log "Fehlende Konfigurationsvariablen:"
        for var in "${MISSING_VARS[@]}"; do
            log " - $var"
        done
        log "Breche ab – bitte Konfigurationsdatei prüfen."
        exit 1
    else
        log "Alle erforderlichen Konfigurationsvariablen sind gesetzt."
    fi
fi

# Funktionen
remote_ssh() {
    ssh -p "$SSHPORT" "$@"
}

remote_scp() {
    scp -P "$SSHPORT" "$@"
}

set_wol_g_enabled() {
    log "Pruefe, ob ethtool installiert ist..."

    if ! command -v ethtool >/dev/null 2>&1; then
        log "ethtool ist nicht installiert, versuche Installation..."
        apt update && apt install -y ethtool || {
            log "Fehler: ethtool konnte nicht installiert werden."
            return 1
        }
    else
        log "ethtool ist bereits installiert."
    fi

    log "Pruefe und setze Wake-on-LAN (WOL) auf 'g' nur bei Interfaces mit statischer IP..."

    for iface in $(ls /sys/class/net | grep -vE '^(lo|tap|vmbr|veth|br|docker|bond|wl)'); do
        if [[ -e "/sys/class/net/$iface/device" ]]; then
            log "Bearbeite physisches Interface: $iface"

            # Aktuellen WOL-Status pruefen
            current_wol=$(ethtool "$iface" 2>/dev/null | awk '/Wake-on:/ {print $2}')
            if [[ "$current_wol" != "g" ]]; then
                log "Setze WOL auf 'g' fuer $iface..."
                ethtool -s "$iface" wol g || log "Fehler beim Setzen von WOL auf $iface"
            else
                log "WOL ist bereits korrekt auf 'g' fuer $iface"
            fi

            # Pruefen, ob ein 'iface $iface inet static' Eintrag existiert
            if grep -qE "^\s*iface\s+$iface\s+inet\s+static" /etc/network/interfaces; then
                if ! grep -A 5 -E "^\s*iface\s+$iface\s+inet\s+static" /etc/network/interfaces | grep -q "post-up ethtool -s $iface wol g"; then
                    log "Ergaenze WOL-Befehl im statischen Block fuer $iface..."
                    sed -i "/^\s*iface\s\+$iface\s\+inet\s\+static/a \    post-up ethtool -s $iface wol g" /etc/network/interfaces
                else
                    log "WOL-Befehl fuer $iface ist bereits im statischen Block vorhanden."
                fi
            else
                log "Kein statischer Eintrag fuer $iface gefunden, keine Aenderung vorgenommen."
            fi
        fi
    done
}

write_zsync_config() {
    local conf_file="/etc/bashclub/$SOURCEHOST.conf"
    log "Writing zsync config to $conf_file"
    {
        echo "target=$ZFSTRGT"
        echo "source=root@$SOURCEHOST"
        echo "sshport=$SSHPORT"
        echo "tag=$ZPUSHTAG"
        echo "snapshot_filter=$ZPUSHFILTER"
        echo "min_keep=$ZPUSHMINKEEP"
        echo "zfs_auto_snapshot_keep=$ZPUSHKEEP"
        echo "zfs_auto_snapshot_label=$ZPUSHLABEL"
        echo "zfs_auto_snapshot_engine=internal"
        echo "checkzfs_disabled=0"
        echo "checkzfs_local=0"
        echo "checkzfs_prefix=miyagi-$SOURCEHOSTNAME-$(hostname)-$ZPUSHTAG"
        echo "checkzfs_max_age=1500,2000"
        echo "checkzfs_max_snapshot_count=180,200"
        echo "checkzfs_spool=1"
        echo "checkzfs_spool_maxage=90000"
    } > "$conf_file"
}

run_zsync() {
    if [[ "$ZSYNC" != "no" ]]; then
        /usr/bin/bashclub-zsync -c "/etc/bashclub/$SOURCEHOST.conf"
    else
        log "Zsync is disabled"
    fi
}

run_remote_updates() {
    if [[ "$UPDATES" == "yes" ]]; then
        ssh "$PBSHOST" apt update && apt dist-upgrade -y
    else
        log "Remote updates disabled"
    fi
}

run_remote_updates() {
    if [[ "$UPDATES" == "yes" ]]; then
        ssh "$PBSHOST" apt update && apt dist-upgrade -y
    else
        log "Remote updates disabled"
    fi
}

send_piggyback_data() {
    # Falls SOURCEHOSTNAME leer ist, ueber SSH vom Zielhost ermitteln
    if [[ -z "${SOURCEHOSTNAME:-}" ]]; then
        log "SOURCEHOSTNAME is empty retrieving via SSH from $SOURCEHOST..."
        SOURCEHOSTNAME=$(ssh -p "$SSHPORT" "$SOURCEHOST" hostname)
        log "Detected SOURCEHOSTNAME: $SOURCEHOSTNAME"
    fi

    local combined_host="miyagi-${SOURCEHOSTNAME}-$(hostname)"
    local filename="90000_${combined_host}"

    log "Do nott forget to add a Host in CMK named: ${combined_host} (without Agent, Piggyback enabled)!"
    log "Creating piggyback file: $filename"

    {
        echo "<<<<${combined_host}>>>>"
        /usr/bin/check_mk_agent
        echo "<<<<>>>>"
    } > "$filename"

    if scp -P "$SSHPORT" "$filename" "$SOURCEHOST:/var/lib/check_mk_agent/spool/"; then
        log "Piggyback data successfully sent to $SOURCEHOST"
    else
        log "ERROR: Failed to send piggyback data to $SOURCEHOST"
    fi
}

run_pbs_backup() {
    if [[ -z "${SOURCEHOSTNAME:-}" ]]; then
        SOURCEHOSTNAME=$(ssh "$SOURCEHOST" hostname)
    fi

    log "Running PBS vzdump job..."

    # PBS-Storage ggf. aktivieren
    log "Checking if PBS storage '$BACKUPSTORE' is enabled on $SOURCEHOST..."
    if ssh root@"$SOURCEHOST" "pvesm status | grep -w '$BACKUPSTORE' | grep -q 'disabled'"; then
        log "PBS storage '$BACKUPSTORE' is disabled. Attempting to enable...sleep 10 Sekunden"
        ssh root@"$SOURCEHOST" "pvesm set '$BACKUPSTORE' --disable 0 && sleep 10"
        pbs_enabled_by_script=true
    else
        log "PBS storage '$BACKUPSTORE' is already enabled."
        pbs_enabled_by_script=false
    fi

    vzdump_success=false

    # Hauptversuch mit --pbs-change-detection-mode
    if ssh root@"$SOURCEHOST" vzdump --pbs-change-detection-mode metadata \
        --node "$SOURCEHOSTNAME" --storage "$BACKUPSTORE" \
        --exclude "$BACKUPEXCLUDE" --mode snapshot --all 1 \
        --notes-template '{{guestname}}'; then

        log "vzdump with change-detection-mode succeeded"
        vzdump_success=true

    else
        log "Fallback: vzdump with change-detection-mode failed, trying without it..."

        if ssh root@"$SOURCEHOST" vzdump \
            --node "$SOURCEHOSTNAME" --storage "$BACKUPSTORE" \
            --exclude "$BACKUPEXCLUDE" --mode snapshot --all 1 \
            --notes-template '{{guestname}}'; then

            log "Fallback vzdump succeeded"
            vzdump_success=true

        else
            log "ERROR: vzdump failed even after fallback"
        fi
    fi

    # PBS-Storage wieder deaktivieren, wenn zuvor aktiviert und erfolgreich
    if [[ "$vzdump_success" == true && "$pbs_enabled_by_script" == true ]]; then
        log "Disabling PBS storage '$BACKUPSTORE' again on $SOURCEHOST..."
        ssh root@"$SOURCEHOST" "pvesm set '$BACKUPSTORE' --disable 1"
    fi

    # Monitoring-Output für Checkmk
    if [[ "$vzdump_success" == true ]]; then
        echo "0 DailyPBS - Daily Backup" > /tmp/cmk_tmp.out
    else
        echo "2 DailyPBS - Daily Backup FAILED" > /tmp/cmk_tmp.out
    fi

    ( echo "<<<local>>>" ; cat /tmp/cmk_tmp.out ) > /tmp/90000_checkpbs
    scp /tmp/90000_checkpbs root@"$SOURCEHOST":/var/lib/check_mk_agent/spool || log "Fehler beim SCP des Monitoring-Outputs"
}


run_maintenance() {
    if [[ "$(date +%u)" == "$MAINTDAY" ]]; then
        log "Running maintenance..."
        PRUNEJOB=$(ssh "$PBSHOST" proxmox-backup-manager prune-job list --output-format json-pretty | grep -m 1 "id" | cut -d'"' -f4)
        ssh root@"$PBSHOST" proxmox-backup-manager prune-job run "$PRUNEJOB"
        ssh root@"$PBSHOST" proxmox-backup-manager garbage-collection start "$BACKUPSTOREPBS"
        ssh root@"$PBSHOST" proxmox-backup-manager verify backup
    else
        log "No maintenance scheduled for today."
    fi
}

run_scrub_stop_src() {
    ssh -p "$SSHPORT" root@"$SOURCEHOST" 'for pool in $(zpool list -H -o name); do
        echo "Stoppe Scrub auf Pool: $pool"
        if zpool status "$pool" | grep -q "scrub in progress"; then
            if zpool scrub -s "$pool"; then
                echo "Scrub auf $pool gestoppt"
            else
                echo "Fehler beim Stoppen des Scrubs auf $pool"
            fi
        else
            echo "Kein aktiver Scrub auf $pool"
        fi
    done'
}

run_scrub_stop_local() {
    for pool in $(zpool list -H -o name); do
        echo "Stoppe Scrub auf Pool: $pool"
        if zpool status "$pool" | grep -q "scrub in progress"; then
            if zpool scrub -s "$pool"; then
                echo "Scrub auf $pool gestoppt"
            else
                echo "Fehler beim Stoppen des Scrubs auf $pool"
            fi
        else
            echo "Kein aktiver Scrub auf $pool"
        fi
    done
}

shutdown_if_requested() {
    log "SHUTDOWN-Variable: '${SHUTDOWN:-nicht gesetzt}'"
    #if [[ "${SHUTDOWN,,}" == "yes" ]]; then
    if [[ "$(echo "$SHUTDOWN" | tr '[:upper:]' '[:lower:]')" == "yes" ]]; then
        send_piggyback_data
        log "Shutting down now..."
        shutdown now
    else
        log "No shutdown requested."
    fi
}

main() {
    log "Backup-Routine startet in 60 Sekunden..."
    sleep 60
    log "Starting full backup routine..."

    SOURCEHOSTNAME=$(ssh "$SOURCEHOST" hostname)

    set_wol_g_enabled
    write_zsync_config
    run_zsync
    run_scrub_stop_local
    run_scrub_stop_src

    if [[ "${BACKUPSERVER,,}" == "yes" ]]; then
        log "BACKUPSERVER ist aktiviert, führe Backup aus..."
        run_maintenance
        run_pbs_backup
    else
        log "BACKUPSERVER ist nicht aktiviert (BACKUPSERVER=$BACKUPSERVER), überspringe Backup."
    fi

    run_remote_updates
    run_updates
    shutdown_if_requested

}

# Funktionsbasierter Aufruf
if [[ "${1:-}" == "help" ]]; then
    echo "Verfuegbare Funktionen:"
    declare -F | awk '{print " - " $3}' | grep -v "^ - _"
    exit 0
elif [[ "${1:-}" =~ ^[a-zA-Z0-9_]+$ && "$(type -t "$1")" == "function" ]]; then
    FUNC="$1"
    shift
    "$FUNC" "$@"
    exit 0
else
    main
fi