productivity.sh

#!/bin/bash
TMP_FILE='/tmp/media_hosts'
HOSTS_FILE='/etc/hosts'
DIVERTISMENT_START="=========================DIVERTISMENT_START====================="
DIVERTISMENT_END="=========================DIVERTISMENT_END======================="

D_START_FOUND=false;
D_END_FOUND=false;

> $TMP_FILE

writeLine() {
	echo "$1" >> $TMP_FILE
}
insertMedia() {
	writeLine "127.0.0.1 www.unimedia.info unimedia.info"
	writeLine "127.0.0.1 www.protv.md protv.md"
	writeLine "127.0.0.1 www.facebook.com facebook.com"
	writeLine "127.0.0.1 www.point.md point.md"
}

if [[ $UID != 0 ]]; then
    echo "Please run this script with sudo:"
    echo "sudo $0 $*"
    exit 1
fi

# begin 
IFS=''
while read line
do
# check for start delimitator
	if [[ "$D_START_FOUND" = false ]]
	then
		echo $line | grep -q $DIVERTISMENT_START

		if [ $? -eq 0 ]
		then
			D_START_FOUND=true
			# keep start delimitator line
			writeLine $DIVERTISMENT_START
			insertMedia
			continue
		fi	
	fi

# check for end delimitator
	if [[ "$D_START_FOUND" = true ]]
	then
		echo $line | grep -q $DIVERTISMENT_END

		if [ $? -eq 0 ]
		then
			D_END_FOUND=true
			# keep end delimitator line
			writeLine $DIVERTISMENT_END
			continue
		fi	
	fi

	# before delimitators
	if [[ "$D_START_FOUND" = false && "$D_END_FOUND" = false ]]
	then
		writeLine $line
	fi

	# after delimitators
	if [[ "$D_START_FOUND" = true && "$D_END_FOUND" = true ]]
	then
		writeLine $line
	fi

done < $HOSTS_FILE

# if delimitators not exist in file, create them
if [[ "$D_START_FOUND" = false && "$D_END_FOUND" = false ]]
then
	writeLine $DIVERTISMENT_START
	insertMedia
	writeLine $DIVERTISMENT_END
fi

cat $TMP_FILE > $HOSTS_FILE