#! /bin/bash

# - Take new tar file as argument		DONE
# - Verify argument is valid			DONE
# - Verify script is running as sudo		DONE
# - Move existing firefox to firefox.OLD	DONE
# - create directory for new installation	DONE
# - unpack tar file to new location		DONE
# - Optional, verify desktop file extsts


helpFunction()
{
  echo " "
  echo "Provides convenient means to install a new Firefox tar file."
  echo "Pass new tar file as argument and this script will handle backing up the current installation and unpacking the new installation."
  echo "This script will prompt before deleting a previous archive."
  echo "Must run with root privileges."
  echo " "
  echo "Usage: $0 [filename]"
  echo " "
}




## Take input and verify file and root user##

filename=$1

if [ "$filename" = "-h" ] || [ "$filename" = "--help" ]; then
  helpFunction
  exit 0
fi

if ! [ -f "$filename" ]; then
  echo "$1 not found."
  helpFunction
  exit 1
fi

if [ -z "$filename" ]
then
  echo " "
  echo "No filename given.  Aborting."
  helpFunction
  exit 1
fi

if [ "$USER" != "root" ]; then
  echo "Must be running as root to install new software.  Use sudo or root user"
  helpFunction
  exit 1
fi

echo "$1 file found"


## Move existing folder to .OLD and delete existing .OLD if needed ##

echo "Checking for old installations"

if [ -d "/opt/firefox.OLD" ]; then
  read -p  "firefox.OLD already exists?  Should I delete it? ENTER to continue or CTRL+C to abort." input
fi

echo "Deleting existing firefox.OLD folder"

rm -rf /opt/firefox.OLD

echo "Moving Existing firefox to firefox.OLD"

mv /opt/firefox /opt/firefox.OLD

echo "Making new firefox directory"

mkdir /opt/firefox

echo "unpacking "$filename" to /opt/firefox"

## Check file type and unpack accordingly ##

if [[ "$filename" == *.tar.xz ]]; then
  echo "Unpacking as tar.xf file" 
  tar -xvf "$filename" -C "/opt/"
elif [[ "$filename" == *.tar.bz2 ]]; then
  echo "Unpacking as tar.bz2 file"
  tar -xjvf "$filename" -C "/opt/"
else
  echo "WARNING: Unknown Compression Type.  Aborting."
  exit 1
fi


# ensure symlink is set

ln -fs /opt/firefox/firefox /usr/local/bin/firefox
echo "Symlink /usr/local/bin/firefox set."

# ensure /opt permissions are set correctly

chown mike:mike /opt/firefox
echo "/opt/firefox permissions set"

# ensure .desktop file is set

if [ -f "firefox.desktop" ]; then
  echo "Setting .desktop file."
  ln -fs /home/mike/Software/firefox/firefox.desktop /usr/local/share/applications
  echo "Done."
else
  echo ""
  echo "WARNING: firefox.desktop not found.  Could not install desktop file."
  echo "Check for existence of firefox.desktop file in this folder."
  exit 1
fi