How to sort issues in issue picker

[jira@migu.cn]

For each bug, we need log which story introduce it, thus I add a issue picker (script field) with jql.

For some projects, in the issue picker I only want to show the stories having same project with the bug. How to set the current project as a parameter of the issue picker jql?

For other projects, the bug may logged in project A, sometimes its corresponding story may locate in project B.   For the bug from project A, in the picker, when showing the story list, I want to put the epic of project A at the front, followed by epics of other projects.  How to sort the stories?

Much appriciated for any help or suggestion.