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

ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
COMPOSE_FILE="${ROOT_DIR}/deploy/docker-compose.prod.yml"
BACKEND_ENV="${ROOT_DIR}/backend/.env"
BACKEND_LOG_DIR="${ROOT_DIR}/backend/logs"
MIGRATIONS_DIR="${ROOT_DIR}/backend/migrations"
HEALTH_URL="${PROD_HEALTH_URL:-http://127.0.0.1:7890/api/health}"
PUBLIC_URL="${PROD_PUBLIC_URL:-http://hfb.221329.cc.cd:7890}"
READY_TIMEOUT="${PROD_READY_TIMEOUT:-120}"

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[1;34m'
NC='\033[0m'

log() {
  printf "${BLUE}[deploy]${NC} %s\n" "$*"
}

log_success() {
  printf "${GREEN}[deploy]${NC} %s\n" "$*"
}

log_warn() {
  printf "${YELLOW}[deploy]${NC} %s\n" "$*"
}

log_error() {
  printf "${RED}[deploy]${NC} %s\n" "$*" >&2
}

need_cmd() {
  if ! command -v "$1" >/dev/null 2>&1; then
    log_error "缺少命令：$1"
    exit 1
  fi
}

env_value() {
  local key="$1"
  awk -F= -v key="${key}" '$1 == key { sub(/^[^=]*=/, ""); print; exit }' "${BACKEND_ENV}"
}

require_env() {
  local key="$1"
  local value
  value="$(env_value "${key}")"
  if [[ -z "${value}" ]]; then
    log_error "backend/.env 缺少或未填写 ${key}"
    exit 1
  fi
  printf "%s" "${value}"
}

show_help() {
  cat << EOF
用法: ./scripts/deploy-prod.sh [选项]

选项:
  --no-build      不重新构建镜像，仅启动已有镜像
  --no-migrate    不执行数据库迁移
  --reset-db      重置数据库（测试阶段使用，会删除并重建）
  --logs          部署完成后跟随查看后端日志
  -h, --help      显示帮助信息

环境变量:
  PROD_HEALTH_URL=http://127.0.0.1:7890/api/health
                  部署后健康检查地址
  PROD_PUBLIC_URL=http://hfb.221329.cc.cd:7890
                  输出给用户看的访问地址
  PROD_READY_TIMEOUT=120
                  等待服务就绪秒数

示例:
  ./scripts/deploy-prod.sh
  ./scripts/deploy-prod.sh --no-build
  ./scripts/deploy-prod.sh --reset-db
  ./scripts/deploy-prod.sh --logs
EOF
}

NO_BUILD=0
NO_MIGRATE=0
RESET_DB=0
FOLLOW_LOGS=0

while [[ $# -gt 0 ]]; do
  case "$1" in
    --no-build)
      NO_BUILD=1
      shift
      ;;
    --no-migrate)
      NO_MIGRATE=1
      shift
      ;;
    --reset-db)
      RESET_DB=1
      shift
      ;;
    --logs)
      FOLLOW_LOGS=1
      shift
      ;;
    -h|--help)
      show_help
      exit 0
      ;;
    *)
      log_error "未知选项：$1"
      show_help
      exit 1
      ;;
  esac
done

if [[ "${RESET_DB}" == "1" && "${NO_MIGRATE}" == "1" ]]; then
  log_error "--reset-db 会清空数据库，不能和 --no-migrate 同时使用"
  exit 1
fi

validate_env() {
  if [[ ! -f "${BACKEND_ENV}" ]]; then
    log_error "未找到 backend/.env，请先执行：cp backend/.env.prod.example backend/.env 并填写生产配置"
    exit 1
  fi

  local app_env mysql_dsn redis_addr storage_endpoint
  app_env="$(require_env APP_ENV)"
  mysql_dsn="$(require_env MYSQL_DSN)"
  redis_addr="$(require_env REDIS_ADDR)"
  storage_endpoint="$(require_env STORAGE_ENDPOINT)"
  require_env MYSQL_DATABASE >/dev/null
  require_env MYSQL_ROOT_PASSWORD >/dev/null
  require_env MYSQL_USER >/dev/null
  require_env MYSQL_PASSWORD >/dev/null
  require_env JWT_SECRET >/dev/null
  require_env MINIO_ROOT_USER >/dev/null
  require_env MINIO_ROOT_PASSWORD >/dev/null
  require_env STORAGE_ACCESS_KEY_ID >/dev/null
  require_env STORAGE_SECRET_ACCESS_KEY >/dev/null

  if [[ "${app_env}" != "production" ]]; then
    log_warn "APP_ENV 当前是 ${app_env}，生产部署建议改为 production"
  fi

  if [[ "${mysql_dsn}" == *"127.0.0.1"* || "${mysql_dsn}" == *"localhost"* ]]; then
    log_error "MYSQL_DSN 仍指向本机，请改为 tcp(mysql:3306)"
    exit 1
  fi
  if [[ "${redis_addr}" == "127.0.0.1:"* || "${redis_addr}" == "localhost:"* ]]; then
    log_error "REDIS_ADDR 仍指向本机，请改为 redis:6379"
    exit 1
  fi
  if [[ "${storage_endpoint}" == *"127.0.0.1"* || "${storage_endpoint}" == *"localhost"* ]]; then
    log_error "STORAGE_ENDPOINT 仍指向本机，请改为 http://minio:9000"
    exit 1
  fi
  if awk -F= '/^[A-Z0-9_]+=/{ if ($0 ~ /=(change-|保持你的|你的)/) found=1 } END { exit found ? 0 : 1 }' "${BACKEND_ENV}"; then
    log_error "backend/.env 里还有占位值，请先替换后再部署"
    exit 1
  fi
}

compose() {
  docker compose -f "${COMPOSE_FILE}" "$@"
}

prepare_log_dir() {
  mkdir -p "${BACKEND_LOG_DIR}"
}

wait_service_healthy() {
  local service="$1"
  local label="$2"
  local attempt

  log "等待 ${label} 就绪..."
  for ((attempt = 1; attempt <= READY_TIMEOUT; attempt++)); do
    local container_id status
    container_id="$(compose ps -q "${service}" 2>/dev/null || true)"
    if [[ -n "${container_id}" ]]; then
      status="$(docker inspect -f '{{if .State.Health}}{{.State.Health.Status}}{{else}}{{.State.Status}}{{end}}' "${container_id}" 2>/dev/null || true)"
      if [[ "${status}" == "healthy" || "${status}" == "running" ]]; then
        log_success "${label} 已就绪"
        return 0
      fi
    fi
    sleep 1
  done

  log_error "${label} 启动超时，请执行：docker compose -f deploy/docker-compose.prod.yml logs ${service}"
  exit 1
}

mysql_exec() {
  compose exec -T mysql sh -c 'MYSQL_PWD="$MYSQL_PASSWORD" mysql -u"$MYSQL_USER" "$@"' sh "$@"
}

mysql_root_exec() {
  compose exec -T mysql sh -c 'MYSQL_PWD="$MYSQL_ROOT_PASSWORD" mysql -uroot "$@"' sh "$@"
}

mysql_scalar() {
  mysql_exec -N -s "$(require_env MYSQL_DATABASE)" -e "$1"
}

ensure_migration_table() {
  mysql_exec "$(require_env MYSQL_DATABASE)" <<'SQL'
CREATE TABLE IF NOT EXISTS schema_migrations (
  version VARCHAR(255) PRIMARY KEY,
  applied_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
SQL
}

bootstrap_existing_schema_history() {
  local migration_count users_exists system_configs_exists
  migration_count="$(mysql_scalar "SELECT COUNT(*) FROM schema_migrations;")"
  users_exists="$(mysql_scalar "SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = DATABASE() AND table_name = 'users';")"
  system_configs_exists="$(mysql_scalar "SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = DATABASE() AND table_name = 'system_configs';")"

  if [[ "${migration_count}" == "0" && "${users_exists}" != "0" && "${system_configs_exists}" != "0" ]]; then
    log_warn "检测到已有表结构但没有迁移记录，将当前 migration 文件标记为已应用"
    local file version
    for file in "${MIGRATIONS_DIR}"/*.sql; do
      version="$(basename "${file}" .sql)"
      mysql_exec "$(require_env MYSQL_DATABASE)" -e \
        "INSERT IGNORE INTO schema_migrations (version) VALUES ('${version}');"
    done
  fi
}

reset_database() {
  if [[ "${RESET_DB}" != "1" ]]; then
    return 0
  fi

  local database
  database="$(require_env MYSQL_DATABASE)"
  if [[ ! "${database}" =~ ^[A-Za-z0-9_]+$ ]]; then
    log_error "MYSQL_DATABASE 只能包含字母、数字和下划线，当前值：${database}"
    exit 1
  fi

  log_warn "重置数据库 ${database}..."
  mysql_root_exec -e \
    "DROP DATABASE IF EXISTS \`${database}\`; CREATE DATABASE \`${database}\` CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;"
  log_success "数据库已重建"
}

run_migrations() {
  if [[ "${NO_MIGRATE}" == "1" ]]; then
    log_warn "已跳过数据库迁移"
    return 0
  fi

  log "执行数据库迁移..."
  ensure_migration_table
  bootstrap_existing_schema_history

  local file version applied
  shopt -s nullglob
  for file in "${MIGRATIONS_DIR}"/*.sql; do
    version="$(basename "${file}" .sql)"
    applied="$(mysql_scalar "SELECT COUNT(*) FROM schema_migrations WHERE version = '${version}';")"
    if [[ "${applied}" != "0" ]]; then
      if [[ "${version}" == "000001_init" ]]; then
        log "同步初始化脚本：${version}"
        mysql_exec "$(require_env MYSQL_DATABASE)" < "${file}"
      else
        log "跳过已应用迁移：${version}"
      fi
      continue
    fi

    log "导入迁移：${version}"
    mysql_exec "$(require_env MYSQL_DATABASE)" < "${file}"
    mysql_exec "$(require_env MYSQL_DATABASE)" -e \
      "INSERT INTO schema_migrations (version) VALUES ('${version}');"
  done
  shopt -u nullglob

  log_success "数据库迁移完成"
}

wait_http_ready() {
  local attempt
  log "等待接口健康检查通过..."
  for ((attempt = 1; attempt <= READY_TIMEOUT; attempt++)); do
    if curl -fsS --max-time 3 "${HEALTH_URL}" >/dev/null 2>&1; then
      log_success "健康检查通过：${HEALTH_URL}"
      return 0
    fi
    sleep 1
  done

  log_error "健康检查超时：${HEALTH_URL}"
  exit 1
}

main() {
  cd "${ROOT_DIR}"
  need_cmd docker
  need_cmd curl
  validate_env
  prepare_log_dir

  log "检查 Docker Compose 配置..."
  compose config >/dev/null

  if [[ "${NO_BUILD}" == "1" ]]; then
    log "启动生产服务..."
    compose up -d
  else
    log "构建并启动生产服务..."
    compose up -d --build
  fi

  wait_service_healthy mysql "MySQL"
  wait_service_healthy redis "Redis"
  wait_service_healthy minio "MinIO"
  reset_database
  run_migrations

  log "重启后端以加载最新数据库状态..."
  compose up -d --no-deps --force-recreate backend
  wait_service_healthy backend "后端"
  wait_http_ready

  log_success "部署完成：${PUBLIC_URL}"
  log "常用命令：docker compose -f deploy/docker-compose.prod.yml logs -f backend"

  if [[ "${FOLLOW_LOGS}" == "1" ]]; then
    compose logs -f backend
  fi
}

main "$@"