#!/bin/bash
# ============================================
# Backup Monitor - Prueft Backup-Alter
# Warnt wenn Backups zu alt oder fehlend
# ============================================
# Aufruf:  bash backup-monitor.sh
# Cron:    0 8 * * *  bash /opt/scripts/backup-monitor.sh
# Quelle:  sgit.space/downloads
# ============================================

set -euo pipefail

# --- Konfiguration ---
# Maximales Alter in Stunden bevor Warnung
MAX_AGE_VZDUMP=26    # vzdump: 1x taeglich = max 26h
MAX_AGE_APP=50       # App-Backups: 1x taeglich = max 50h

# Backup-Verzeichnisse pruefen (anpassen!)
VZDUMP_DIR="/mnt/backup/dump"        # vzdump Storage
APP_BACKUP_DIRS=(
    "/mnt/backup/app-backups/mail"
    "/mnt/backup/app-backups/n8n"
    "/mnt/backup/app-backups/bitwarden"
)

# Telegram (optional)
TELEGRAM_ENABLED=false
# TELEGRAM_BOT_TOKEN="your-token"
# TELEGRAM_CHAT_ID="your-chat-id"

# --- Farben ---
GREEN='\033[0;32m'
RED='\033[0;31m'
YELLOW='\033[1;33m'
NC='\033[0m'

WARNINGS=0
OK=0
ERRORS=""

log() { echo -e "$1"; }

check_backup_age() {
    local DIR="$1"
    local MAX_HOURS="$2"
    local LABEL="$3"

    if [ ! -d "$DIR" ]; then
        log "${RED}FEHLER${NC}: $LABEL — Verzeichnis $DIR nicht gefunden"
        WARNINGS=$((WARNINGS + 1))
        ERRORS="${ERRORS}\n$LABEL: Verzeichnis fehlt"
        return
    fi

    # Neueste Datei finden
    NEWEST=$(find "$DIR" -type f -name "*.tar" -o -name "*.gz" -o -name "*.zst" -o -name "*.lzo" -o -name "*.sql" -o -name "*.dump" 2>/dev/null | xargs -r ls -t 2>/dev/null | head -1)

    if [ -z "$NEWEST" ]; then
        log "${RED}FEHLER${NC}: $LABEL — Keine Backup-Dateien gefunden"
        WARNINGS=$((WARNINGS + 1))
        ERRORS="${ERRORS}\n$LABEL: Keine Dateien"
        return
    fi

    # Alter berechnen
    FILE_AGE_SEC=$(( $(date +%s) - $(stat -c %Y "$NEWEST") ))
    FILE_AGE_HOURS=$(( FILE_AGE_SEC / 3600 ))
    FILE_SIZE=$(du -sh "$NEWEST" | cut -f1)
    FILE_NAME=$(basename "$NEWEST")

    if [ "$FILE_AGE_HOURS" -gt "$MAX_HOURS" ]; then
        log "${RED}WARNUNG${NC}: $LABEL — ${FILE_AGE_HOURS}h alt (max: ${MAX_HOURS}h)"
        log "         Datei: $FILE_NAME ($FILE_SIZE)"
        WARNINGS=$((WARNINGS + 1))
        ERRORS="${ERRORS}\n$LABEL: ${FILE_AGE_HOURS}h alt"
    else
        log "${GREEN}OK${NC}: $LABEL — ${FILE_AGE_HOURS}h alt ($FILE_SIZE)"
        OK=$((OK + 1))
    fi
}

# === vzdump Backups ===
log "\n===== Backup Monitor ====="
log "Datum: $(date '+%Y-%m-%d %H:%M')\n"

log "--- vzdump Backups ---"
if [ -d "$VZDUMP_DIR" ]; then
    # Pro Container das neueste Backup pruefen
    for CONF in $(find "$VZDUMP_DIR" -name "vzdump-lxc-*.tar.*" -o -name "vzdump-lxc-*.vma.*" 2>/dev/null | sed 's/.*vzdump-lxc-\([0-9]*\).*/\1/' | sort -un); do
        CT_DIR="$VZDUMP_DIR"
        LABEL="vzdump CT $CONF"
        NEWEST=$(find "$CT_DIR" -name "vzdump-lxc-${CONF}-*" -type f 2>/dev/null | xargs -r ls -t 2>/dev/null | head -1)
        if [ -n "$NEWEST" ]; then
            FILE_AGE_SEC=$(( $(date +%s) - $(stat -c %Y "$NEWEST") ))
            FILE_AGE_HOURS=$(( FILE_AGE_SEC / 3600 ))
            FILE_SIZE=$(du -sh "$NEWEST" | cut -f1)
            if [ "$FILE_AGE_HOURS" -gt "$MAX_AGE_VZDUMP" ]; then
                log "${RED}WARNUNG${NC}: $LABEL — ${FILE_AGE_HOURS}h alt"
                WARNINGS=$((WARNINGS + 1))
                ERRORS="${ERRORS}\n$LABEL: ${FILE_AGE_HOURS}h alt"
            else
                log "${GREEN}OK${NC}: $LABEL — ${FILE_AGE_HOURS}h ($FILE_SIZE)"
                OK=$((OK + 1))
            fi
        fi
    done
else
    log "${YELLOW}SKIP${NC}: vzdump-Verzeichnis nicht gefunden ($VZDUMP_DIR)"
fi

# === App-Level Backups ===
log "\n--- App-Level Backups ---"
for DIR in "${APP_BACKUP_DIRS[@]}"; do
    LABEL=$(basename "$DIR")
    check_backup_age "$DIR" "$MAX_AGE_APP" "$LABEL"
done

# === Zusammenfassung ===
log "\n===== Ergebnis ====="
log "OK: $OK | Warnungen: $WARNINGS"

if [ "$WARNINGS" -gt 0 ]; then
    log "${RED}ACHTUNG: $WARNINGS Backup(s) pruefen!${NC}"

    if [ "$TELEGRAM_ENABLED" = true ]; then
        MSG="<b>Backup Monitor</b>
OK: $OK | Warnungen: $WARNINGS
$(echo -e "$ERRORS")"
        curl -s -X POST "https://api.telegram.org/bot${TELEGRAM_BOT_TOKEN}/sendMessage" \
            -d chat_id="${TELEGRAM_CHAT_ID}" -d text="$MSG" -d parse_mode="HTML" > /dev/null 2>&1 || true
    fi
    exit 1
fi

exit 0