#!/usr/bin/env bash
# Pull WordPress CT101 (pve-hetzner) → CT600 wp-mirror (pve-mu-3)
# CT101 impact: read-only mysqldump (--single-transaction) + read-only tar. No restarts.
set -euo pipefail

HETZNER_HOST="${HETZNER_HOST:-root@100.88.230.59}"
HETZNER_CT="${HETZNER_CT:-101}"
MIRROR_CT="${MIRROR_CT:-600}"
STAGING="${STAGING:-/opt/wp-mirror-sync/staging}"
LOG="${LOG:-/var/log/wp-mirror-sync.log}"
LOCK_FILE="/var/run/wp-mirror-sync.lock"
FAILOVER_FLAG="/opt/wp-mirror-sync/FAILOVER_ACTIVE"
MIRROR_SITEURL="http://192.168.178.142"
MYSQL_USER="wordpress"
MYSQL_PASS="astral66"
MYSQL_DB="wordpress"
WP_VOL="/var/lib/docker/volumes/wordpress_wp_data/_data"

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

tar_sync_files() {
  rm -rf "${STAGING}/wpfiles"
  mkdir -p "${STAGING}/wpfiles"
  ssh -o BatchMode=yes -o ConnectTimeout=30 "$HETZNER_HOST" \
    "ionice -c3 nice -n 19 pct exec ${HETZNER_CT} -- tar c -C ${WP_VOL} \
      --exclude=wp-content/cache \
      --exclude=wp-content/debug.log \
      --exclude=wp-content/upgrade \
      . 2>/dev/null" | tar x -C "${STAGING}/wpfiles"
}

exec 9>"$LOCK_FILE"
if ! flock -n 9; then
  log "SKIP: another sync is running"
  exit 0
fi

if [[ -f "$FAILOVER_FLAG" ]]; then
  log "SKIP: ${FAILOVER_FLAG} present (manual failover)"
  exit 0
fi

if ! command -v pct >/dev/null 2>&1; then
  log "ABORT: must run on Proxmox host with pct (pve-mu-3)"
  exit 1
fi

mkdir -p "$STAGING" "$(dirname "$LOG")"

log "Checking CT101 health..."
if ! ssh -o BatchMode=yes -o ConnectTimeout=15 "$HETZNER_HOST" \
  "pct exec ${HETZNER_CT} -- curl -sf -o /dev/null --max-time 15 http://127.0.0.1/"; then
  log "ABORT: CT101 does not respond on http://127.0.0.1/"
  exit 1
fi

log "START sync CT101 → CT600"

DB_FILE="${STAGING}/wordpress.sql.gz"
log "DB dump (single-transaction, read-only)..."
if ! ssh -o BatchMode=yes -o ConnectTimeout=30 "$HETZNER_HOST" \
  "ionice -c3 nice -n 19 pct exec ${HETZNER_CT} -- docker exec wordpress-mysql mysqldump \
    -u${MYSQL_USER} -p${MYSQL_PASS} \
    --single-transaction --quick --skip-lock-tables \
    --add-drop-table ${MYSQL_DB} 2>/dev/null" | gzip > "${DB_FILE}.tmp"; then
  log "ABORT: mysqldump failed"
  rm -f "${DB_FILE}.tmp"
  exit 1
fi
mv "${DB_FILE}.tmp" "$DB_FILE"
log "DB dump size: $(du -h "$DB_FILE" | awk '{print $1}')"

log "File sync via tar (read-only, ~5–8 min)..."
tar_sync_files
log "Files staged: $(du -sh "${STAGING}/wpfiles" | awk '{print $1}')"

log "Starting CT600 for import..."
if [[ "$(pct status "$MIRROR_CT" | awk '{print $2}')" != "running" ]]; then
  pct start "$MIRROR_CT"
fi
for _ in $(seq 1 45); do
  if pct exec "$MIRROR_CT" -- docker info >/dev/null 2>&1; then
    break
  fi
  sleep 2
done

pct exec "$MIRROR_CT" -- docker stop wordpress-app 2>/dev/null || true

log "Import DB into CT600..."
gunzip -c "$DB_FILE" | pct exec "$MIRROR_CT" -- docker exec -i wordpress-mysql \
  mysql -u"$MYSQL_USER" -p"$MYSQL_PASS" "$MYSQL_DB"

log "Import files into CT600..."
tar c -C "${STAGING}/wpfiles" . 2>/dev/null | pct exec "$MIRROR_CT" -- tar x -C "$WP_VOL"

log "Reset mirror idle siteurl/home..."
pct exec "$MIRROR_CT" -- docker exec wordpress-mysql mysql -u"$MYSQL_USER" -p"$MYSQL_PASS" "$MYSQL_DB" -e \
  "UPDATE wp_options SET option_value='${MIRROR_SITEURL}' WHERE option_name IN ('siteurl','home');"

pct exec "$MIRROR_CT" -- docker start wordpress-app
sleep 5

POSTS="$(pct exec "$MIRROR_CT" -- docker exec wordpress-mysql mysql -u"$MYSQL_USER" -p"$MYSQL_PASS" -N -e \
  "SELECT COUNT(*) FROM wp_posts WHERE post_status='publish' AND post_type='post';" "$MYSQL_DB" 2>/dev/null)"
LAST="$(pct exec "$MIRROR_CT" -- docker exec wordpress-mysql mysql -u"$MYSQL_USER" -p"$MYSQL_PASS" -N -e \
  "SELECT MAX(post_date) FROM wp_posts WHERE post_type='post';" "$MYSQL_DB" 2>/dev/null)"
log "Mirror verified: ${POSTS} published posts, latest ${LAST}"

if ! ssh -o BatchMode=yes -o ConnectTimeout=15 "$HETZNER_HOST" \
  "pct exec ${HETZNER_CT} -- curl -sf -o /dev/null --max-time 15 http://127.0.0.1/"; then
  log "WARN: CT101 health check failed AFTER sync — investigate immediately"
  exit 1
fi

log "Stopping CT600 (standby)..."
pct stop "$MIRROR_CT"
log "DONE"