#!/bin/bash

# === Load environment ===
ENV_FILE="./AdGuardBackup.env"
if [ ! -f "$ENV_FILE" ]; then
    echo "Environment file not found: $ENV_FILE"
    exit 1
fi
source "$ENV_FILE"

# === Sanity Check ===
sanity_check() {
    if [ -z "$HA_SSH_KEY" ]; then
        echo "Error: HA_SSH_KEY is not set."; exit 1
    fi
    if [ -z "$HA_SSH_USER" ]; then
        echo "Error: HA_SSH_USER is not set."; exit 1
    fi
    if [ -z "$BACKUP_DEST" ]; then
        echo "Error: BACKUP_DEST is not set."; exit 1
    fi
    if [ -z "$SERVER_LIST" ]; then
        echo "Error: SERVER_LIST is not set."; exit 1
    fi
    if [ "$NTFY_ENABLED" == "true" ]; then
        if [ -z "$NTFY_SERVER" ] || [ -z "$NTFY_TOPIC" ]; then
            echo "Error: NTFY settings are incomplete."; exit 1
        fi
    fi
    if [ "$DISCORD_ENABLED" == "true" ]; then
        if [ -z "$DISCORD_WEBHOOK_URL" ]; then
            echo "Error: DISCORD_WEBHOOK_URL is not set."; exit 1
        fi
    fi
}

# === Notification Functions ===
send_ntfy_notification() {
    local message="$1"
    if [ "$NTFY_ENABLED" = true ]; then
        curl -s -X POST -d "$message" "$NTFY_SERVER/$NTFY_TOPIC" >/dev/null
    fi
}

send_discord_notification() {
    local message="$1"
    if [ "$DISCORD_ENABLED" = true ]; then
        curl -s -X POST -H "Content-Type: application/json" \
             -d "{\"content\": \"$message\"}" "$DISCORD_WEBHOOK_URL" >/dev/null
    fi
}

# === Run Sanity Check ===
sanity_check

# === Setup Variables ===
TIMESTAMP=$(date '+%Y-%m-%d_%H-%M-%S')
START_TIME=$(date +%s)
LOG_FILE="$BACKUP_DEST/backup-$TIMESTAMP.log"
REMOTE_FILE=${REMOTE_FILE:-"/opt/AdGuardHome/AdGuardHome.yaml"}

mkdir -p "$BACKUP_DEST"
touch "$LOG_FILE"

# Parse server list
IFS=' ' read -r -a SERVERS <<< "$SERVER_LIST"

# === Start Logging and Notify ===
echo "[$(date)] Starting AdGuardHome backup..." | tee -a "$LOG_FILE"
send_ntfy_notification "🛡️ AdGuardHome backup started at $TIMESTAMP"
send_discord_notification "🛡️ AdGuardHome backup started at $TIMESTAMP"

# === Main Backup Loop ===
for HOST in "${SERVERS[@]}"; do
    SERVER="$HA_SSH_USER@$HOST"
    echo "[$(date)] Connecting to $SERVER..." | tee -a "$LOG_FILE"

    REMOTE_HOSTNAME=$(ssh -i "$HA_SSH_KEY" -o StrictHostKeyChecking=no "$SERVER" 'hostname' 2>/dev/null)
    if [[ -z "$REMOTE_HOSTNAME" ]]; then
        echo "[$(date)] ❌ Failed to retrieve hostname from $HOST" | tee -a "$LOG_FILE"
        send_ntfy_notification "❌ Backup failed: could not retrieve hostname from $HOST"
        send_discord_notification "❌ Backup failed: could not retrieve hostname from $HOST"
        continue
    fi

    DEST_FILE="$BACKUP_DEST/AdGuardHome.yaml-$REMOTE_HOSTNAME-$TIMESTAMP"

    scp -i "$HA_SSH_KEY" -o StrictHostKeyChecking=no "$SERVER:$REMOTE_FILE" "$DEST_FILE" 2>>"$LOG_FILE"
    if [[ $? -eq 0 ]]; then
        echo "[$(date)] ✅ Backup successful: $DEST_FILE" | tee -a "$LOG_FILE"
        send_ntfy_notification "✅ Backup complete for $REMOTE_HOSTNAME"
        send_discord_notification "✅ Backup complete for $REMOTE_HOSTNAME"
    else
        echo "[$(date)] ❌ Failed to copy from $HOST" | tee -a "$LOG_FILE"
        send_ntfy_notification "❌ Backup failed for $REMOTE_HOSTNAME"
        send_discord_notification "❌ Backup failed for $REMOTE_HOSTNAME"
    fi
done

# === Finalize ===
END_TIME=$(date +%s)
DURATION=$((END_TIME - START_TIME))

echo "[$(date)] Backup script completed in ${DURATION}s." | tee -a "$LOG_FILE"
send_ntfy_notification "📦 Backup completed in ${DURATION}s"
send_discord_notification "📦 Backup completed in ${DURATION}s"