Splitting multiple overlapping date range interval in postgresql - sql

I am using postgresql version 10.9 and I am trying to split overlapping intervals from 2 different tables that record events.
For each interval of the main table, I need to detect the person movement (arrival or departure) that overlaps the main interval, and split it for each prod_line by the event. If the person movement is arrival, I need to take the highest value of a 5 minutes interval consecutive arrivals. If the person movement is departure, I need to take the lowest value of a 5 minutes interval of consecutive departures.
I only found samples of merging overlapping intervals for date ranges within the same table.
I tried to write a function that loops through the main data set and for each interval to loop through the attendance intervals and return overlapping intervals.
I failed to make the attendance intervals take into account the highest arrival_time within a 5 minute interval and the lowest value within a 5 minute interval for departure time and also further compare it to the main current interval to properly split it as expected.
My 2 tables have the following structure
main (prod_line text, item_code text, start_time timestamp without time zone, end_time timestamp without time zone);
attendance(person_id text, prod_line text, arrival_time timestamp without time zone, departure_time timestamp without time zone);
having the following sample data for Main:
"RS-5";"110067805";"2019-06-11 06:30:41";"2019-06-11 15:00:05"
and for Attendance
11770;"RS-5";"2019-06-11 06:30:09";"2019-06-11 11:00:12"
675;"RS-5";"2019-06-11 06:30:14";"2019-06-11 10:00:01"
11504;"RS-5";"2019-06-11 06:30:17";"2019-06-11 10:00:07"
101;"RS-5";"2019-06-11 06:30:23";"2019-06-11 11:00:10"
627;"RS-5";"2019-06-11 06:30:25";"2019-06-11 11:00:20"
11765;"RS-5";"2019-06-11 06:34:29";"2019-06-11 11:00:01"
675;"RS-5";"2019-06-11 11:30:09";"2019-06-11 15:00:25"
627;"RS-5";"2019-06-11 11:30:16";"2019-06-11 15:00:24"
11504;"RS-5";"2019-06-11 11:30:19";"2019-06-11 15:00:18"
11770;"RS-5";"2019-06-11 11:30:22";"2019-06-11 15:00:15"
11765;"RS-5";"2019-06-11 11:30:25";"2019-06-11 15:00:12"
101;"RS-5";"2019-06-11 11:30:27";"2019-06-11 15:00:30"
353;"RS-5";"2019-06-11 15:01:39";"2019-06-11 15:10:35"
11712;"RS-5";"2019-06-11 15:01:42";"2019-06-11 15:10:34"
817;"RS-5";"2019-06-11 15:01:44";"2019-06-11 15:10:32"
1337;"RS-5";"2019-06-11 15:01:46";"2019-06-11 15:10:30"
1363;"RS-5";"2019-06-11 15:01:48";"2019-06-11 15:10:28"
1510;"RS-5";"2019-06-11 15:01:50";"2019-06-11 15:10:24"
Rextester Fiddle
Basically, I would like to get a result of the intervals looking like this:
result (prod_line text, item_code text, start_time timestamp without time zone, end_time timestamp without time zone);
with the values
"RS-5";"110067805";"2019-06-11 06:34:29";"2019-06-11 10:00:01"
"RS-5";"110067805";"2019-06-11 10:00:07";"2019-06-11 11:00:01"
"RS-5";"110067805";"2019-06-11 11:00:01";"2019-06-11 11:30:27"
"RS-5";"110067805";"2019-06-11 11:30:27";"2019-06-11 15:00:05"

In case anyone else needs a solution for this, I figured something out (maybe not the best but it works)
The solution is available here

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SQL Fiddle