[OS] indexYZ.txt files

#!/bin/bash
#if the number of arguments is not 3
if [ $# -ne 3 ]
then
    echo "USAGE: `basename $0` number1 number2 destination_folder"
    exit 1
fi
#if the directory exists remove it, then create it again
if [ -d $3 ]
then
    rm $3
fi
mkdir $3
TO=$3
number1=$1
number2=$2
#get all txt files from the home directory that have been modified between the last 10 and 14 days.
txt_files=`find ./home -name "\.txt$" -type f -mtime +${number1} -mtime -${number2}`
number_of_txt_files=`find ./home -name "\.txt$" -type f -mtime +${number1} -mtime -${number2} | wc -l`
touch temp.txt
i=0
while [ i -lt $number_of_txt_files ]
do
    #so we dump the files that are below or equal to 150B size and stick to more superior ones
    filesize=`ls -l ./home | grep ${text_files[${i}]} | awk 'print $4'`
    if [ filesize -gt 150 ]
    then
        echo "${txt_files[${i}]}" >> temp.txt
    fi
    i=`expr $i + 1`
done
for row in $(cat temp.txt)
do
    #apparently this is how we count how many times a ceratin word appears in a file
    echo_count=`grep -o 'echo' $row | wc -l`
    #if there ain't a file with indexY.txt name where Y is the echo_count, make one and continue with another file
    if [ ! -f $TO/index${echo_count} ]
    then
        cp ./home/$row $TO/index${echo_count}.txt
        continue;
    fi
    #if there exists a file with that name, we add another digit character that kinda counts in a way how many files have the exact number of echos in em
    Zcount=1
    flag=0
    while [ flag -eq 0 ]
    do
        #if a file like this ain't existing, create it finally and get out, continue with another file
        if [ ! -f $TO/index${echo_count}${Zcount} ]
        then
            cp ./home/$row $TO/index${echo_count}${Zcount}.txt
            break;
        else
            #if a file like that exists try again by incrementing Z
            Zcount=`expr $Zcount + 1`
        fi
    done
done
#let us see what we've got...
echo `ls -l | $TO | awk 'print $9'`