awk - Duplicate, Rearrange and Add columns to file - awk

Question

I would like to :
duplicate 2 columns
switch position between columns
add a variable (as: 0,128,128) in a column at the end of the file
My file :
chr1 3006607 3006623 Class 0 +
chr1 3006607 3006623 Class 0 +
chr1 3006607 3006623 Class 0 +
chr1 3006607 3006623 Class 0 +
chr1 3006607 3006623 Class 0 +
....continue
My code :
cat FILE.txt | awk 'BEGIN { FS=" "; OFS="\t" } { print $1, $2=$2 "\t" $2, $3=$3 "\t" $3, $4, $5, $6 }' | awk 'BEGIN { FS="\t"; OFS="\t" } { print $1, $2, $4, $6, $7, $8, $3, $5 "\t" "0,128,128" }' > FILE.bed
My out-put :
chr1 3006607 3006623 Class 0 +
3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 +
3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 +
3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 +
3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 +
3006607 3006623 0,128,128
...continue
ERROR = DUPLICATED COLUMNS AND THE ADDED ONE ARE IN A ROW BELOW
What I would like to obtain !
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
.....continue
What am I doing wrong?
Am I missing NR or paste0?

Answer 1

If the code in your question produces output that puts the duplicated values on a new row then your input has DOS line endings (or similar?) causing that to happen because your code will not do that.
See Why does my tool output overwrite itself and how do I fix it? for how to handle DOS line endings and then this is all you really need instead of the script in your question:
$ awk -v OFS='\t' '{print $0, $2, $3, "0,128,128"}' file
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128

Answer 2

You may use:
awk -v OFS='\t' -v s='0,128,128' '{$1=$1; print $0, $2, $3, s}' file
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
chr1 3006607 3006623 Class 0 + 3006607 3006623 0,128,128
$1=$1 is to force $0 to be reformatted with tab as field separator.