#!/usr/bin/env bash
set -euo pipefail

ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"

BACKUP_DIR="${BACKUP_DIR:-$ROOT_DIR/deploy/trialrun/backups}"
mkdir -p "$BACKUP_DIR"

TS="$(date +%Y%m%d_%H%M%S)"
OUT_FILE="${OUT_FILE:-$BACKUP_DIR/hyb-oa-db-${TS}.dump}"

if [[ -e "$OUT_FILE" ]]; then
  echo "[ERR] backup output already exists: $OUT_FILE" >&2
  exit 1
fi

mkdir -p "$(dirname "$OUT_FILE")"

if [[ -z "${DATABASE_URL:-}" ]]; then
  echo "[ERR] DATABASE_URL is required" >&2
  exit 1
fi

DB_TOOL_MODE="${DB_TOOL_MODE:-auto}"
if [[ "$DB_TOOL_MODE" != "auto" && "$DB_TOOL_MODE" != "host" && "$DB_TOOL_MODE" != "docker" ]]; then
  echo "[ERR] DB_TOOL_MODE must be auto, host, or docker" >&2
  exit 1
fi

echo "[INFO] DB backup start: $OUT_FILE"

if [[ "$DB_TOOL_MODE" != "docker" ]] && command -v pg_dump >/dev/null 2>&1; then
  if pg_dump "$DATABASE_URL" --format=c --no-owner --no-acl --file "$OUT_FILE"; then
    if [[ ! -s "$OUT_FILE" ]]; then
      echo "[ERR] DB backup is empty: $OUT_FILE" >&2
      exit 1
    fi
    echo "[OK] DB backup done (pg_dump): $OUT_FILE"
    exit 0
  fi
  rm -f -- "$OUT_FILE"
  if [[ "$DB_TOOL_MODE" == "host" ]]; then
    echo "[ERR] host pg_dump failed" >&2
    exit 1
  fi
  echo "[WARN] host pg_dump failed; trying docker fallback" >&2
fi

if [[ "$DB_TOOL_MODE" == "host" ]]; then
  echo "[ERR] DB_TOOL_MODE=host requires pg_dump" >&2
  exit 1
fi

if ! command -v docker >/dev/null 2>&1; then
  echo "[ERR] pg_dump not found and docker not available" >&2
  exit 1
fi

DB_CONTAINER="${DB_CONTAINER:-}"
POSTGRES_DB="${POSTGRES_DB:-}"
POSTGRES_USER="${POSTGRES_USER:-}"
POSTGRES_PASSWORD="${POSTGRES_PASSWORD:-}"

if [[ -z "$DB_CONTAINER" ]]; then
  echo "[ERR] Using docker fallback requires explicit DB_CONTAINER" >&2
  exit 1
fi

if [[ -z "$POSTGRES_DB" || -z "$POSTGRES_USER" || -z "$POSTGRES_PASSWORD" ]]; then
  echo "[ERR] Using docker fallback requires POSTGRES_DB/POSTGRES_USER/POSTGRES_PASSWORD" >&2
  exit 1
fi

if ! PGPASSWORD="$POSTGRES_PASSWORD" docker exec -e PGPASSWORD "$DB_CONTAINER" \
  pg_dump -U "$POSTGRES_USER" -d "$POSTGRES_DB" --format=c --no-owner --no-acl \
  >"$OUT_FILE"; then
  rm -f -- "$OUT_FILE"
  echo "[ERR] docker pg_dump failed" >&2
  exit 1
fi

if [[ ! -s "$OUT_FILE" ]]; then
  echo "[ERR] DB backup is empty: $OUT_FILE" >&2
  exit 1
fi

echo "[OK] DB backup done (docker exec): $OUT_FILE"