const koa = require('koa')

//koa路由器，不同于express天生自带路由，koa需要引入路由中间件

const koaRouter = require('koa-router')

//koa的静态文件处理中间件

const static = require('koa-static')

//处理post过来文件的中间件

const body = require('koa-better-body');

//配合better-body使用

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

// url解析

const url = require('url')

//不同于express，koa需要new

const server = new koa()

//监听端口

server.listen(8080)

//配置接受文件存储位置，扩展名是否加上

server.use(convert(body({

  uploadDir: './upload',

  keepExtensions: true

})))

//正常koa的使用方法use

server.use(async (ctx,next) => {

    ctx.user_id = '123456789'

    //跨域可能需要加上的2个http头

    ctx.set('Access-Control-Allow-Origin','*')

    ctx.set('Access-Control-Allow-Headers','*')

    await next()

})

//路由需要new

const r1 = new koaRouter()

//嵌套路由

r1.use('/test', async ctx => {

    //获取http头信息,例如x-token是自定义的http头

    let token = ctx.headers['x-token']

})

r1.use('/api', require('./routers/api.routers'))

//返回给koa server的时候需要调用routes函数

server.use(r1.routes())

//koa静态文件中间件

server.use(static('./www'))

const koaRouter = require('koa-router')

const db = require('../libs/mysql')

const r1 = new koaRouter()

//操作日志

r1.get('/collect/:type/:data', async ctx => {

    // ctx.params获取url上的顶死的参数

    let {type,data} = ctx.params

    // ctx.query获取?后的参数

    let {username, password} = ctx.query

    await db.insert('collect_table', {

        type, data

    })

    ctx.body = {OK: true}

})

//获取餐厅

r1.post('/restaurant/:page/:size', async ctx => {

    //获取post body上的参数

    console.log(this.request.body)    // if buffer or text

    console.log(this.request.files)   // if multipart or urlencoded

    console.log(this.request.fields)  // if json

// -------------------------------------------------------------------------

    let {page,size} = ctx.params

    let data = await db.query(`

        SELECT * FROM restaurant_table LIMIT ${page*size},${size}

    `)

    ctx.body = data

})

//嵌套路由需要返回routes()

module.exports = r1.routes()

const mysql = require('mysql')

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

const assert = require('assert')

const db = mysql.createPool({

    host:config.DB_HOST,

    port:config.DB_PORT,

    database:config.DB_DATABASE,

    user:config.DB_USER,

    password:config.DB_PASS

})

function filter(val) {

    return val.replace(/"/g,'\\"').replace(/'/g,'\\\'')

}

db._query = db.query

db.query = function(sql) {

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

        db._query(sql, (err, data) => {

            if(err) {

                reject(err)

            } else {

                resolve(data)

            }

        })

    })

}

db.select = function(table, fields, data) {

    let WHERE = ''

    if(!data) {

        WHERE = '1 = 1'

    } else {

        let arr = [];

        for(let key in data){

            arr.push(`${key}="${filter(data[key])}"`)

        }

        WHERE = arr.join(' AND ')

    }

    return db.query(`SELECT ${fields} FROM ${table} WHERE ${WHERE}`)

}

db.insert = function(table, data) {

    let keys = []

    let vals = []

    for(let key in data) {

        keys.push(key)

        vals.push('"'+filter(data[key].toString())+'"')

    }

    return db.query(`INSERT INTO ${table} (${keys.join(',')}) VALUES(${vals.join(',')})`)

}

db.update = function(table, data, where) {

    assert(where)

    assert(typeof where == 'object')

    let arr = []

    for(let i in data) {

        arr.push(`${i}="${data[i]}"`)

    }

    let whereArr = []

    for(let i in where) {

        whereArr.push(`${i}="${where[i]}"`)

    }

    return db.query(`UPDATE ${table} SET ${arr.join(',')} WHERE ${whereArr.join(' AND ')}`)

}

db.delete = function(table, data) {

    assert(data)

    assert(typeof data == 'object')

    let arr = []

    for(let i in data) {

        arr.push(`${i}="${data[i]}"`)

    }

    return db.query(`DELETE FROM ${table} WHERE ${arr.join(' AND ')}`)

}

module.exports = db