#!/usr/bin/env bash
# =============================================================================
# Kitchen — Migrate from Production
# =============================================================================
# Copies the live production kitchen_gp database and invoice files into the
# new stack (kitchen_db on LXC 100 + invoice_data volume on LXC 110).
#
# Run this from the Proxmox host AFTER kitchen and kds are deployed:
#   bash /opt/kitchen/migrate-from-production.sh
#
# It is safe to re-run: the final step truncates and re-imports, so a second
# run simply refreshes the data. Stop kitchen + kds before running if live.
#
# FILL IN SECTION BELOW before first run (D10: confirm production host + creds).
# =============================================================================
set -euo pipefail

# ── Production source (fill in) ──────────────────────────────────────────────
PROD_HOST=""          # e.g. 192.168.1.50 or laptop hostname
PROD_PG_PORT="5432"
PROD_PG_USER="postgres"
PROD_DB="kitchen_gp"  # production DB name
PROD_DATA_DIR=""      # path to invoice data on production, e.g. /home/user/data/invoices

# ── Stack target ─────────────────────────────────────────────────────────────
STACK_PG_HOST="10.10.10.100"
STACK_PG_PORT="5432"
STACK_PG_SUPER="postgres"   # postgres superuser in hotel-manage-postgres container
STACK_DB="kitchen_db"
STACK_DB_USER="kitchen"     # created by deploy_kitchen()
KITCHEN_LXC=110

# ── Load KITCHEN_DB_PASS from credentials file ────────────────────────────────
CREDS_FILE=/root/hotel-manage-credentials.txt
if [[ -f "$CREDS_FILE" ]]; then
  KITCHEN_DB_PASS=$(grep '^KITCHEN_DB_PASS=' "$CREDS_FILE" | cut -d= -f2- | head -1)
fi
if [[ -z "${KITCHEN_DB_PASS:-}" ]]; then
  echo "ERROR: KITCHEN_DB_PASS not found in ${CREDS_FILE}" >&2
  exit 1
fi

# =============================================================================
RD="\033[01;31m"; GN="\033[1;92m"; YW="\033[33m"; CL="\033[m"
die() { printf "${RD}✗ %s${CL}\n" "$*" >&2; exit 1; }
ok()  { printf "${GN}✓ %s${CL}\n" "$*"; }
inf() { printf "${YW}◌ %s${CL}\n" "$*"; }

[[ -z "$PROD_HOST" ]]     && die "PROD_HOST not set — edit this script first (see D10)"
[[ -z "$PROD_DATA_DIR" ]] && die "PROD_DATA_DIR not set — edit this script first"

DUMP_FILE="/tmp/kitchen_migration_$(date +%Y%m%d_%H%M%S).dump"

# =============================================================================
# 1. Dump production DB
# =============================================================================
inf "Dumping ${PROD_DB} from ${PROD_HOST}..."
PGPASSWORD="${PROD_PG_PASS:-}" pg_dump \
  -h "$PROD_HOST" -p "$PROD_PG_PORT" -U "$PROD_PG_USER" \
  -Fc --no-owner --no-privileges \
  "$PROD_DB" > "$DUMP_FILE"
ok "Dump written to ${DUMP_FILE} ($(du -sh "$DUMP_FILE" | cut -f1))"

# =============================================================================
# 2. Stop kitchen + kds so no writes arrive during restore
# =============================================================================
inf "Stopping kitchen and kds containers..."
pct exec 110 -- bash -c "cd /opt/kitchen && docker compose stop backend" 2>/dev/null || true
pct exec 125 -- bash -c "cd /opt/kds    && docker compose stop backend" 2>/dev/null || true
ok "Services stopped"

# =============================================================================
# 3. Drop + recreate kitchen_db (clean slate for restore)
# =============================================================================
inf "Recreating ${STACK_DB} on ${STACK_PG_HOST}..."
# Push dump file into LXC 100 for restore
pct push 100 "$DUMP_FILE" /tmp/kitchen_restore.dump

pct exec 100 -- bash -c "
  docker exec hotel-manage-postgres psql -U postgres -c \
    \"SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE datname = '${STACK_DB}' AND pid <> pg_backend_pid();\"
  docker exec hotel-manage-postgres psql -U postgres -c \
    \"DROP DATABASE IF EXISTS ${STACK_DB};\"
  docker exec hotel-manage-postgres psql -U postgres -c \
    \"CREATE DATABASE ${STACK_DB} OWNER ${STACK_DB_USER};\"
  docker exec hotel-manage-postgres psql -U postgres -d ${STACK_DB} -c \
    \"GRANT ALL ON SCHEMA public TO ${STACK_DB_USER};\"
"
ok "${STACK_DB} recreated"

# =============================================================================
# 4. Restore dump into kitchen_db
# =============================================================================
inf "Restoring dump into ${STACK_DB}..."
pct exec 100 -- bash -c "
  docker cp /tmp/kitchen_restore.dump hotel-manage-postgres:/tmp/
  docker exec hotel-manage-postgres pg_restore \
    -U postgres -d ${STACK_DB} \
    --no-owner --no-privileges \
    --exit-on-error \
    /tmp/kitchen_restore.dump
  docker exec hotel-manage-postgres rm -f /tmp/kitchen_restore.dump
  rm -f /tmp/kitchen_restore.dump
"
ok "Dump restored to ${STACK_DB}"

# =============================================================================
# 5. Re-run KDS migrations (add KDS columns not in production dump)
# =============================================================================
inf "Applying KDS schema additions to ${STACK_DB}..."
pct exec 125 -- bash -c "
  cd /opt/kds
  docker compose run --rm -e DATABASE_URL=postgresql://${STACK_DB_USER}:${KITCHEN_DB_PASS}@${STACK_PG_HOST}:${STACK_PG_PORT}/${STACK_DB} \
    backend python -c \"
import asyncio
from database import engine, Base
from migrations.add_kds_tables import run_migration as m1
from migrations.add_kds_course_flow import run_migration as m2
from migrations.add_kds_order_tracking import run_migration as m3
from migrations.add_kds_bookings_refresh import run_migration as m4
async def run():
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)
    for m in [m1, m2, m3, m4]:
        try:
            await m()
        except Exception as e:
            print(f'migration warning (may be ok): {e}')
asyncio.run(run())
\"" || true
ok "KDS schema additions applied"

# =============================================================================
# 6. Rsync invoice data files
# =============================================================================
inf "Syncing invoice data files from ${PROD_HOST}:${PROD_DATA_DIR} ..."
# Find the docker volume mount on LXC 110
VOLUME_PATH=$(pct exec 110 -- bash -c "
  docker inspect kitchen-backend-1 2>/dev/null | \
  python3 -c \"import sys,json; mounts=json.load(sys.stdin)[0]['Mounts']; \
  print(next(m['Source'] for m in mounts if 'invoice_data' in m.get('Name','') or '/app/data' in m.get('Destination','')))\"\
" 2>/dev/null || echo "")

if [[ -z "$VOLUME_PATH" ]]; then
  inf "Could not auto-detect invoice volume path — skipping file sync"
  inf "Manually rsync: ${PROD_HOST}:${PROD_DATA_DIR}/ → LXC 110's invoice_data volume"
else
  rsync -avz --progress "${PROD_HOST}:${PROD_DATA_DIR}/" \
    "root@${STACK_PG_HOST}:${VOLUME_PATH}/" || true
  ok "Invoice files synced to ${VOLUME_PATH}"
fi

# =============================================================================
# 7. Restart services
# =============================================================================
inf "Restarting kitchen and kds..."
pct exec 110 -- bash -c "cd /opt/kitchen && docker compose start backend"
pct exec 125 -- bash -c "cd /opt/kds    && docker compose start backend"
ok "Services restarted"

# =============================================================================
# 8. Verification report
# =============================================================================
inf "Running verification report..."

REPORT=$(pct exec 100 -- bash -c "
  docker exec hotel-manage-postgres psql -U postgres -d ${STACK_DB} -t -A -F'|' -c \"
    SELECT 'invoices'    , COUNT(*) FROM invoices;
    SELECT 'line_items'  , COUNT(*) FROM invoice_line_items;
    SELECT 'suppliers'   , COUNT(*) FROM suppliers;
    SELECT 'ingredients' , COUNT(*) FROM ingredients;
    SELECT 'recipes'     , COUNT(*) FROM recipes;
    SELECT 'resos_bookings', COUNT(*) FROM resos_bookings;
  \"
" 2>/dev/null || echo "verification query failed")

printf "\n${GN}══ Migration verification ══════════════════════════════════${CL}\n"
while IFS='|' read -r table count; do
  printf "  %-20s %s rows\n" "$table" "$count"
done <<< "$REPORT"
printf "\n"

# Monthly invoice total sanity check (compare with production before cutover)
MONTHLY=$(pct exec 100 -- bash -c "
  docker exec hotel-manage-postgres psql -U postgres -d ${STACK_DB} -t -A -F'|' -c \"
    SELECT TO_CHAR(invoice_date, 'YYYY-MM'), COUNT(*), ROUND(SUM(total_exc_vat)::numeric, 2)
    FROM invoices
    WHERE invoice_date >= NOW() - INTERVAL '6 months'
    GROUP BY 1 ORDER BY 1 DESC LIMIT 6;
  \"
" 2>/dev/null || echo "")

if [[ -n "$MONTHLY" ]]; then
  printf "${GN}  Monthly invoice counts (last 6 months)${CL}\n"
  while IFS='|' read -r month cnt total; do
    printf "  %s   %4s invoices   £%s\n" "$month" "$cnt" "$total"
  done <<< "$MONTHLY"
fi

printf "\n${GN}Done. Clean up dump file:${CL}\n"
printf "  rm -f %s\n\n" "$DUMP_FILE"