Scriptrunner - Update start and end dates for Epics and Initiatives

[Milos Pejkovic]

Dear community,

I hope that all of you are safe and well.

Maybe someone of you can help us. We are using Jira + Advanced roadmaps and we would like to automate updating the dates in Advanced roadmaps.

Is there a way to make a Listener in Scriptrunner which will monitor Update issue events and do the following? Or is there a better way? :) 

1. Update Start date of Epic
   Any update of the start date of any issue type being child issue of any Epic should check if the current Epic start date is empty, if yes, update it with the same date. If the Epic start date is not empty, the function should check if the current Epic start date is after the date of child start date and if yes, update the Epic start date with the same date as the start date of the child issue.
2. Update Start date of Initiative
   Any update of the start date of any issue type being child issue of any Initiative should check if the Initiative current start date is empty, if yes, update it with the same date. If the Initiative start date is not empty, the function should check if the current Initiative start date is after the date of child start date and if yes, update the Initiative start date with the same date as the start date of the child issue.
3. Update End date of Epic
   Any update of the end date of any issue type being child issue of any Epic should check if the current Epic end date is empty, if yes, update it with the same date. If the Epic end date is not empty, the function should check if the current Epic end date is before the date of the child end date and if yes, update the Epic end date with the same date as the end date of the child issue.
4. Update End date of Initiative
   Any update of the end date of any issue type being child issue of any Initiative should check if the current Initiative end date is empty, if yes, update it with the same date. If the Initiative end date is not empty, the function should check if the current Initiative end date is before the date of the child end date and if yes, update the Initiative end date with the same date as the end date of the child issue.

Start date = customField_13033
End date = customField_13034

Many thanks and regards!