const express = require('express')

const bodyParser = require('body-parser')

const multipart = require('connect-multiparty')

const config = require('./mock.config.js')

const Mock = require('mockjs')

const app = express()

// 解决跨域问题

app.use((req, res, next) => {

res.header('Access-Control-Allow-Origin', 'http://localhost:3000');

res.header('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE');

res.header('Access-Control-Allow-Headers', 'Content-Type');

next();

})

// body-parser 负责解析请求体, 可屏蔽掉不同请求不同编码格式及代码的边界异常的复杂处理过程,会将解析出来的内容挂在req.body对象上

// connect-multiparty: 处理文件上传的模块. 会在服务器上创建临时文件夹,但会不删除临时文件夹,需主动删除

const multipartMiddleware = multipart()

app.use(bodyParser.urlencoded({extended:false}))

app.use(bodyParser.json())

// 定义mock接口

const mock = (data, params) => {

if(Object.prototype.toString.call(data) === '[object Object]') {

return Mock.mock(data)

}

else if (typeof data === 'function') {

return Mock.mock(data(params))

}

else {

return 'error: data should be an Oject or a function'

}

}

config.forEach(({method, url, data}) => {

if(method === 'get') {

app.get(url, (req,res) => {

res.json(mock(data,req.query))

})

}

else if(method === 'post') {

app.post(url, multipartMiddleware, (req,res) => {

res.json(mock(data,req.body))

})

}

else if(method === 'jsonp') {

app.get(url, (req, res) => {

const query = req.query

const mockData = JSON.stringify(mock(data, req.query))

const callback = `typeof ${query.callback} === 'function' && ${query.callback}(${mockData})`

res.send(callback)

})

}

})

// 支持自定义接口

let port = 8081

process.argv.forEach((arg, index, arr) => {

if(arg === '--port') {

port = arr[index +1] || 8081

return false

}

})

module.exports = app.listen(port, ()=> {

console.log('Mock Server: http://localhost:' + port)

})