Shell Programming and Scripting

I post my question here also because i have a difficult script to create that do the following:

The examples i got dont support it.
Lets say the input file is:
ABC^1^~^data^x
ABC^2^~^data^x
ABC^3^~^data^x
DEF^4^~^data^y
DEF^4^~^data^z
DEF^5^~^data^y
DEF^5^~^data^z
DEF^6^~^data^z
DEF^6^~^data^y
XYZ^7^~^data^t

Now I would like to group couple of fields(field 2 and field 5) and concatenate them with comma according to my key which is the first field.
My output should be:

ABC^1,2,3^~^data^x
DEF^4,5,6^~^data^y,z
XYZ^7^~^data^t

Notice that I would like to print all the line's fields.

Is it possible?

This is the start but i have problem on duplicate data, does anyone have any idea regarding it

BEGIN { FS=OFS="^" }
{
arr[$1] = ($1 in arr) ? arr[$1] "," $2 : $2
arr2[$1] = ($1 in arr2) ? arr2[$1] "," $5 : $5
#In order not to repeat the value, how can i validate it
}
END {
if ( length(arr2) > length(arr1) ) {

}
if ( length(arr1) > length(arr2) ) {

}
if(length(arr1) == length(arr2) {

}

for (i in arr)
# I need to print all
}

Very similar question to https://www.unix.com/shell-programming-and-scripting/19562-shell-script-comparing-files-file.html
You should be easily able to mod the python code presented there.