Wrap a single oversize column with awk / bash (pretty print) - bash

Question

Im having this table structure (assume that the delimiters are tabs):
AAA BBBB CCC
01 Item Description here
02 Meti A very very veeeery long description which will easily extend the recommended output width of 80 characters.
03 Etim Last description
What i want is this:
AAA BBBB CCC
01 Item Description here
02 Meti A very very veeeery
long description which
will easily extend the
recommended output width
of 80 characters.
03 Etim Last description
That means I want to split $3 into an array of strings with predefined WIDTH, where the first element is appended "normally" to the current line and all subsequent elements get a new line width identation according to the padding of the first two columns (padding could also be fixed if thats easier).
Alternatively, the text in $0 could be split by a GLOBAL_WIDTH (e.g. 80 chars) into first string and "rest" -> first string gets printed "normally" with printf, the rest is split by GLOBAL_WIDTH - (COLPAD1 + COLPAD2) and appended width new lines as above.
I tried to work with fmt and fold after my awk formatting (which is basically just putting headings to the table) but they do not reflect awk's field perceptance of course.
How can I achieve this using bash tools and / or awk?

Answer 1

First build a test file (called file.txt):
echo "AA BBBB CCC
01 Item Description here
02 Meti A very very veeeery long description which will easily extend the recommended output width of 80 characters.
03 Etim Last description" > file.txt
Now the script (called ./split-columns.sh):
#!/bin/bash
FILE=$1
#find position of 3rd column (starting with 'CCC')
padding=`cat $FILE | head -n1 | grep -aob 'CCC' | grep -oE '[0-9]+'`
paddingstr=`printf "%-${padding}s" ' '`
#set max length
maxcolsize=50
maxlen=$(($padding + $maxcolsize))
cat $FILE | while read line; do
#split the line only if it exceeds the desired length
if [[ ${#line} -gt $maxlen ]] ; then
echo "$line" | fmt -s -w$maxcolsize - | head -n1
echo "$line" | fmt -s -w$maxcolsize - | tail -n+2 | sed "s/^/$paddingstr/"
else
echo "$line";
fi;
done;
Finally run it with the file as a single argument
./split-columns.sh file.txt > fixed-width-file.txt
Output will be:
AA BBBB CCC
01 Item Description here
02 Meti A very very veeeery long description
which will easily extend the recommended output
width of 80 characters.
03 Etim Last description

Answer 2

You can try Perl one-liner
perl -lpe ' s/(.{20,}?)\s/$1\n\t /g ' file
with the given inputs
$ cat thurse.txt
AAA BBBB CCC
01 Item Description here
02 Meti A very very veeeery long description which will easily extend the recommended output width of 80 characters.
03 Etim Last description
$ perl -lpe ' s/(.{20,}?)\s/$1\n\t /g ' thurse.txt
AAA BBBB CCC
01 Item Description
here
02 Meti A very very
veeeery long description
which will easily extend
the recommended output
width of 80 characters.
03 Etim Last description
$
If you want to try with length window of 30/40/50
$ perl -lpe ' s/(.{30,}?)\s/$1\n\t /g ' thurse.txt
AAA BBBB CCC
01 Item Description here
02 Meti A very very veeeery
long description which will easily
extend the recommended output width
of 80 characters.
03 Etim Last description
$ perl -lpe ' s/(.{40,}?)\s/$1\n\t /g ' thurse.txt
AAA BBBB CCC
01 Item Description here
02 Meti A very very veeeery long description
which will easily extend the recommended
output width of 80 characters.
03 Etim Last description
$ perl -lpe ' s/(.{50,}?)\s/$1\n\t /g ' thurse.txt
AAA BBBB CCC
01 Item Description here
02 Meti A very very veeeery long description which
will easily extend the recommended output width of
80 characters.
03 Etim Last description
$

Answer 3

#!/usr/bin/awk -f
# Read standard input, which should be a file of lines each line
# containing tab-separated strings. The string values may be very long.
# Columnate the output by
# wrapping long strings onto multiple lines within each field's
# specified length.
# Arguments are numeric field lengths. If an input line contains more
# values than the # of field lengths supplied, the last field length will
# be re-used.
#
# arguments are the field lengths
# invoke like this: wrapcolumns 30 40 40
BEGIN {
FS=" ";
for (i = 1; i < ARGC; i++) {
fieldlengths[i-1] = ARGV[i];
ARGV[i]="";
}
if (ARGC < 2) {
print "usage: wrapcolumns length1 ... lengthn";
exit;
}
}
function blanks(n) {
result = " ";
while (length(result) < n) {
result = result result;
}
return substr(result, 1, n);
}
{
# ARGC - 1 is the length of the fieldlengths array
# So ARGC - 2 is the index of its last element because its zero-origin.
# if the input line has more fields than the fieldlengths array,
# use the last element.
# any nonempty fields left?
gotanyleft = 1;
while (gotanyleft == 1) {
gotanyleft = 0;
for (i = 1; i <= NF; i++) {
# length of the current field
len = (ARGC - 2 < i) ? (fieldlengths[ARGC - 2]) : fieldlengths[i - 1];
# print that much of the current field and remove that much from the front
printf "%s", substr($(i) blanks(len), 1, len) ":::"
$(i) = substr($(i), len + 1);
if ($(i) != "") {
gotanyleft = 1;
}
}
print ""
}
}

Answer 4

loop-free awk-solution :
{m,g}awk -v ______="${WIDTH}" 'BEGIN {
1 OFS = ""
1 FS = "\t"
1 ___ = "\32\23"
1 __ = sprintf("\n%*s",
(_+=_^=_<_)+_^!_+(_+=_____=_+=_+_)+_____,__)
1 ____ = sprintf("%*s",______-length(__),"")
1 gsub(".",".",____)
sub("[.].......$","..?.?.?.?.?.?.?.[ ]",____)
1 ______ = _
} $!NF = sprintf("%.*s %*s %-*s %-s", _<_,_= $NF,_____,
$2,______, $--NF, substr("",gsub(____,
("&")___,_) * gsub("("(___)")+$","",_),
__ * gsub( (___), (__),_) )_)'
|
AAA BBBB CCC
01 Item Description here
02 Meti A very very veeeery long description which
will easily extend the recommended output
width of 80 characters.
03 Etim Last description