'use strict';

/**
 * 应用入口
 * Created by liamjung on 2018/5/21.
 */
require('co')(function* () {
  let config = require('./app_config');

  let appConfig;

  // 加载配置
  if (typeof config === 'function') {
    appConfig = yield config();
  } else {
    appConfig = global.appConfig = config;
  }

  const { Log } = require('@libfintech/api-gateway-core/log/log');
  global.Log = Log;

  const { Pipeline } = require('@libfintech/api-gateway-core/entity/pipeline');

  const Koa = require('koa');
  const bodyParser = require('@libfintech/api-gateway-core/util/koa_body_parser');
  const logger = require('koa-logger');
  const stripAnsi = require('strip-ansi');
  const fs = require('fs');
  const appRoot = require('app-root-path');

  const app = new Koa();
  app.on('error', (err, ctx) => Log.error('server error', err, ctx));

  /**
   * 响应客户端
   * @param ctx
   * @param resp
   */
  async function responseClient(ctx, resp) {
    // 设置状态
    ctx.response.status = resp.status;

    if (resp.headers) {
      // fix: The response headers can't include "Content-Length" with chunked encoding
      delete resp.headers['transfer-encoding'];

      // 设置响应头
      await ctx.response.set(resp.headers);
    }
    if (!ctx.type && resp.body && resp.body.startsWith('{')) ctx.type = 'application/json';
    ctx.length = !resp.body ? 0 : Buffer.byteLength(resp.body, 'utf8');

    // 刷新任何已设置的响应头，并开始主体
    ctx.response.flushHeaders();

    // 设置响应体
    ctx.response.body = resp.body;
  }

  // 中间件
  app.use(
    bodyParser({
      enableTypes: ['json', 'form', 'file', 'text'],
      extendTypes: {
        // will parse text/json type body as a JSON string
        json: ['text/json'],
        text: ['*/*'],
      },
    }),
  );
  app.use(
    logger((str, args) => {
      Log.info(stripAnsi(str));
    }),
  );

  // 初始化
  app.use(async (ctx, next) => {
    // 初始化管道
    ctx.pipeline = new Pipeline(ctx);

    ctx.pipeline.logger.debug('headers:\t\t' + JSON.stringify(ctx.request.headers));
    ctx.pipeline.logger.debug(ctx.request.method + ':' + ctx.pipeline.request.originalPath);
    ctx.pipeline.logger.debug('querystring:\t\t' + ctx.pipeline.request.querystring);
    let contentType = ctx.headers['content-type'];
    if (!contentType || !contentType.toLowerCase().includes('multipart/form-data'))
      ctx.pipeline.logger.debug('body:\t\t' + ctx.pipeline.request.body);
    ctx.pipeline.logger.debug(
      '----------------------------------------------------------------------------------------------------------------------',
    );

    await next();
  });

  // 引入插件
  appConfig.plugins.forEach((item, index) => {
    let path = item.path;

    if (!item.enable) {
      // 未开启时，忽略
      Log.info('Plugin (index: ' + index + '; path: ' + path + ') is not enabled');

      return;
    }

    // 入口方法名称必须为main
    let main = require(path + '/index').main;

    let configPath = item.config_path;

    // 插件配置
    let configs = {};
    if (configPath) {
      let configFiles = fs.readdirSync(appRoot.path + item.config_path);
      for (let cf of configFiles) {
        if (cf.endsWith('.conf.js')) configs = Object.assign(configs, require('.' + item.config_path + '/' + cf));
      }
    }

    app.use(async (ctx, next) => {
      ctx.pipeline.logger.info('Plugin (index: ' + index + '; path: ' + path + ')');

      try {
        await main(ctx.pipeline, configs);

        await next();
      } catch (err) {
        if (err.status) {
          // 响应客户端
          await responseClient(ctx, {
            status: err.status,
            headers: err.headers,
            body: err.body,
          });
        } else ctx.pipeline.logger.error('server error', err, ctx);
      }
    });

    Log.info('Load plugin (index: ' + index + '; path: ' + path + ')');
  });

  app.use(async (ctx, next) => await responseClient(ctx, ctx.pipeline.response));

  Log.info('App has been started, listen ' + appConfig.port + '.');

  app.listen(appConfig.port);
});