import { z } from 'zod';

const configSchema = z.object({
  NODE_ENV: z.enum(['development', 'test', 'production']).default('development'),
  QIPAI_API_HOST: z.string().min(1).default('0.0.0.0'),
  QIPAI_API_PORT: z.coerce.number().int().min(1).max(65535).default(3001),
  QIPAI_API_VERSION: z.string().min(1).default('0.1.0'),
  QIPAI_API_CORS_ORIGINS: z.string().default('https://api.txyundm.cn'),
  QIPAI_MYSQL_HOST: z.string().min(1).default('127.0.0.1'),
  QIPAI_MYSQL_PORT: z.coerce.number().int().min(1).max(65535).default(3306),
  QIPAI_MYSQL_DATABASE: z.string().min(1).default('qipai'),
  QIPAI_MYSQL_USER: z.string().min(1).default('qipai_app'),
  QIPAI_MYSQL_PASSWORD: z.string().default(''),
  QIPAI_MYSQL_CONNECTION_LIMIT: z.coerce.number().int().min(1).max(50).default(10),
  QIPAI_JWT_SECRET: z.string().min(32).default('development-only-change-this-jwt-secret'),
  QIPAI_ACCESS_TOKEN_TTL_SECONDS: z.coerce.number().int().min(60).max(86400).default(900),
  QIPAI_SESSION_TTL_SECONDS: z.coerce.number().int().min(300).max(2592000).default(604800),
  QIPAI_WECHAT_APP_SECRETS: z.string().default('{}'),
  QIPAI_MQTT_URL: z.string().url().default('mqtt://101.42.38.246:1883'),
  QIPAI_MQTT_USERNAME: z.string().default(''),
  QIPAI_MQTT_PASSWORD: z.string().default('')
});

export type AppConfig = ReturnType<typeof loadConfig>;

export function loadConfig(env: NodeJS.ProcessEnv = process.env) {
  const parsed = configSchema.parse(env);
  if (
    parsed.NODE_ENV === 'production'
    && parsed.QIPAI_JWT_SECRET === 'development-only-change-this-jwt-secret'
  ) {
    throw new Error('QIPAI_JWT_SECRET must be explicitly configured in production.');
  }

  return {
    nodeEnv: parsed.NODE_ENV,
    host: parsed.QIPAI_API_HOST,
    port: parsed.QIPAI_API_PORT,
    version: parsed.QIPAI_API_VERSION,
    corsOrigins: parsed.QIPAI_API_CORS_ORIGINS.split(',').map((item) => item.trim()).filter(Boolean),
    mysql: {
      host: parsed.QIPAI_MYSQL_HOST,
      port: parsed.QIPAI_MYSQL_PORT,
      database: parsed.QIPAI_MYSQL_DATABASE,
      user: parsed.QIPAI_MYSQL_USER,
      credential: parsed.QIPAI_MYSQL_PASSWORD,
      passwordConfigured: parsed.QIPAI_MYSQL_PASSWORD.length > 0,
      connectionLimit: parsed.QIPAI_MYSQL_CONNECTION_LIMIT
    },
    auth: {
      jwtSecret: parsed.QIPAI_JWT_SECRET,
      accessTokenTtlSeconds: parsed.QIPAI_ACCESS_TOKEN_TTL_SECONDS,
      sessionTtlSeconds: parsed.QIPAI_SESSION_TTL_SECONDS,
      wechatAppSecretsJson: parsed.QIPAI_WECHAT_APP_SECRETS
    },
    mqtt: {
      url: parsed.QIPAI_MQTT_URL,
      usernameConfigured: parsed.QIPAI_MQTT_USERNAME.length > 0,
      passwordConfigured: parsed.QIPAI_MQTT_PASSWORD.length > 0
    }
  };
}