const express = require('express');
const cors = require('cors');
const swaggerUi = require('swagger-ui-express');
const logger = require('./config/logger');
const swaggerSpec = require('./config/swagger');
const routes = require('./routes');
const { notFound, errorHandler } = require('./middlewares/errorHandler');

/**
 * 创建 Express 应用
 */
function createApp() {
  const app = express();

  // 中间件配置
  app.use(cors()); // 跨域支持
  app.use(express.json()); // JSON 解析
  app.use(express.urlencoded({ extended: true })); // URL 编码解析
  app.use(logger); // 日志记录

  // API 文档 - Swagger UI
  app.use('/api-docs', swaggerUi.serve, swaggerUi.setup(swaggerSpec, {
    explorer: true,
    customCss: '.swagger-ui .topbar { display: none }',
    customSiteTitle: 'Steel Prices Service API Documentation',
    swaggerOptions: {
      persistAuthorization: true,
      displayRequestDuration: true,
      docExpansion: 'list',
      filter: true,
      showRequestHeaders: true,
      tryItOutEnabled: true
    }
  }));

  // 路由
  app.use('/', routes);

  // 错误处理
  app.use(notFound);
  app.use(errorHandler);

  return app;
}

module.exports = createApp;