Linux shell script, parsing each line [closed] - sed

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I am facing a problem with my shell script (I'm using SH):
I have a file with multiple line including mail adressess, for example:
abcd
plm
name_aA.2isurnamec#Text.com -> this is a line that checks the correct condition
random efgh
aaaaaa
naaame_aB.3isurnamec#Text.ro ->same (this is not part of the file)
I have used grep to filter the correct mail adresses like this:
grep -E '^[a-z][a-zA-Z_]*.[0-9][a-zA-Z0-9]+#[A-Z][A-Z0-9]{,12}.(ro|com|eu)$' file.txt
I have to write a shell that cheks the file and prints the following (for the above example it would be like this ):
"Incorrect:" abcd
"Incorrect:" plm
"Correct:" name_aA.2isurnamec#Text.com
"Incorrect:" random efgh
"Incorrect:" aaaaaa
"Correct:" naaame_aB.3isurnamec#Text.ro
I want to solve this problem using grep or sed, while, if, or pipes etc i dont want to use lists or other things.
I have tried using something like this
grep condition abc.txt | while read -r line ; do
echo "Processing $line"
# your code goes here
done
but it only prints the correct lines, and i know that i can also print the lines that dont match the grep condition using -v on grep, but i want to print the lines in the order they appear in the text file.
I'm having trouble trying to parse each line of the file, or maybe i don't need to parse the lines 1
by 1, i really dont know how to solve it.
If you could help me i would appreciate it.
Thanks

Answer 1

#!/bin/bash
pattern='^[a-z][a-zA-Z_]*\.[0-9][a-zA-Z0-9]+#[A-Z][A-Za-z0-9]{,12}\.(ro|com|eu)$'
while read line; do
if [ "$line" ]; then
if echo "$line" | grep -E -q $pattern; then
echo "\"Correct:\" $line"
else
echo "\"Incorrect:\" $line"
fi
fi
done
Invoke like this, assuming the bash script is called filter and the text file, text.txt: ./filter < text.txt.
Note that the full stops in the regular expression are escaped and that the domain name can contain lowercase letters (although, I think that your regex is too restrictive). Other characters are not escaped because the string is in single quotes.
while reads the standard input line by line into $line; the first if skips the empty lines; the second one checks $line against $pattern (-q suppresses grep output).