const Koa = require('koa');

const Router = require('koa-router');

const app = new Koa();

const router = new Router();

const views = require('koa-views');

const json = require('koa-json');

const onerror = require('koa-onerror');

const bodyparser = require('koa-bodyparser');

const path = require('path');

const logger = require('koa-logger');

const request = require('request');

// error handler

onerror(app)

// middlewares

app.use(bodyparser())

    .use(json())

    .use(logger())

    .use(require('koa-static')(__dirname + '/public'))

    .use(views(path.join(__dirname, '/views'), {

        options: { settings: { views: path.join(__dirname, 'views') } },

        map: { 'html': 'nunjucks' },

        extension: 'html'

    }))

    .use(router.routes())

    .use(router.allowedMethods())

// x-response-time

app.use(async function(ctx, next) {

    const start = new Date();

    await next();

    const ms = new Date() - start;

    ctx.set('X-Response-Time', `${ms}ms`);

});

// logger

app.use(async function(ctx, next) {

    const start = new Date();

    await next();

    const ms = new Date() - start;

    console.log(`${ctx.method} ${ctx.url} - ${ms}`);

});

app.on('error', (err, ctx) =>

    log.error('server error', err, ctx)

);

router.get('/', async(ctx, next) => {

    var bd = "bd";

    // 从服务器获取数据

   bd = await getData();

    ctx.state = {

        title: 'Koa2',

        name: bd

     }

    // 发送到页面

     return  await ctx.render('index', ctx.state)

})

//获取服务器数据

async function  getData(){

    return new Promise((resolve,reject)=>{

        request("https://www.baidu.com",(error,response,body)=>{

            if(error){

                reject("error")

            }else{

                resolve("thank you");／／body

            }

        })

    })

}

router.get('/b', async(ctx, next) => {

    ctx.state = {

        title: 'Koa2',

        name: '小明-list'

    }

    await ctx.render('b', ctx.state)

})

app.listen(3000);

console.log('listen http://localhost:3000');