/* 
   By default, this workflow sends at most one email per day, per error type,
   per workflow. The second time a specific error is raised from the same 
   workflow in the same 24-hour period, no email will be sent. You can modify
   this behavior to apply any notification logic you'd like.
*/
import dateFormat from 'dateformat';
import { differenceInHours } from 'date-fns';

const { code, msg, ts } = event.error
const { id, workflow_id, workflow_name } = event.original_context


// $checkpoint allows us to save any JSON-serializable data in a workflow,
// reading it on subsequent invocations. Here, we save the last time we 
// saw a specific error on a workflow, exiting if we've seen the error recently.
if ($checkpoint && $checkpoint[workflow_id] && $checkpoint[workflow_id][code]) {
  console.log(`We've seen error ${code} for workflow ${workflow_id} before. Checking the time of the last event.`)
  // Check if we've seen this error within the past 24 hours
  const lastErrorDate = new Date($checkpoint[workflow_id][code].lastSeen)
  const diffInHours = differenceInHours(new Date(ts), lastErrorDate)
  if (diffInHours <= 24) {
    $end(`Error ${code} occurred ${diffInHours} hours ago. No notification to send.`)
  }
}

// We haven't seen the error recently, so we can send our error notitication
const errorTime = dateFormat(event.original_context.ts, "h:MM:ss TT Z")
const errorDate = dateFormat(event.original_context.ts, "dddd, mmmm dS, yyyy")

const formattedErrMsg = msg ? `${code} — ${msg}` : code

this.subject = `[pipedream] Error in workflow ${workflow_name || workflow_id} at ${errorTime}`
this.text = `Your workflow at https://pipedream.com/@/${workflow_id}?e=${id} generated the following error at ${errorTime} on ${errorDate}:

${formattedErrMsg}`

const options = {
  subject: params.subject,
  text: params.text,
}
if (params.html) {
  options.html = params.html
}
$send.email(options)

import { merge } from 'lodash-es';

const { code, ts } = event.error
const { workflow_id } = event.original_context

// The first time our workflow runs, initialize $checkpoint
if (!$checkpoint) {
  console.log("First run of Global Error Workflow. Checkpointing initial state")
  $checkpoint = {} // workflow error gets set on merge below
}

// Finally, we need to checkpoint the time we saw this error for 
// this workflow, merging it with the existing checkpoint data.
merge($checkpoint, {
  [workflow_id]: {
    [code]: {
      lastSeen: ts
    }
  }
})