import { Context, Request } from 'koa'
import * as fp from 'lodash/fp'
import { LogFn } from 'pino'
import { Stream } from 'stream'
import defaultLogger from '../../logger'

export default function requestLoggerFactory({
  logger = defaultLogger.debug.bind(defaultLogger) as LogFn,
}: { logger?: LogFn } = {}) {
  return async function requestLogger(ctx: Context, next: () => void) {
    const start = Date.now()

    const {
      method,
      originalUrl,
      headers: requestHeaders,
      body: requestBody,
      ip: remoteIp,
    }: Request & { body?: any } = ctx.request
    const httpRequest = fp.omitBy(fp.isNil, {
      method,
      remoteIp,
      url: originalUrl,
      referrer: ctx.request.get('referer'),
      userAgent: ctx.request.get('user-agent'),
      headers: requestHeaders,
      body: requestBody,
    })

    await next()

    const ms = Date.now() - start
    const { status, headers: responseHeaders, body: responseBody = '' } = ctx.response
    const httpResponse = fp.omitBy(fp.isNil, {
      status,
      headers: responseHeaders,
      body: responseBody instanceof Stream ? '[Stream]' : responseBody,
    })

    logger(
      {
        httpRequest,
        httpResponse,
        duration: `${ms}ms`,
      },
      `${method}: ${originalUrl}`
    )
  }
}