#!/usr/local/bin/bash

#The dialog tool to create our user interface needs a temp file
#that it can write output to
DIALOG_TEMP_FILE="/tmp/week7.dialog.tempfile"

#Grab a list of all the usernames in the password file
#The second grep excludes user who have just / for their home directory
usernamesList=`cat /etc/passwd | grep -v "^#" | cut -d":" -f1,6 | grep -v "/$" | cut -d":" -f1`

#Assemble a list of users for the dialog command
#This will look like this
# 1 danielt  2 wharrop  3 mdieker
userlist=""
counter=0
for username in $usernamesList
do
	counter="$((counter + 1))"
	userlist="$userlist  $counter  $username"
done


#Show a menu with an item for each user we found above
#The user will have to select an item from this list
menuWidth=30
menuHeight=30
menuItems=20
dialog --menu "Available Users" $menuHeight $menuWidth $menuItems  $userlist  2> $DIALOG_TEMP_FILE
  if [ $? = 1 ]; then
         clear
         exit 0
   fi
itemSelected=`cat ${DIALOG_TEMP_FILE}`

#Work out which user this corresponded to
#Do this by getting the Nth line of the userlist
usernameSelected=`echo "${usernamesList}" | head -n ${itemSelected} | tail -n 1 `

#Work out the other bits of information we're supposed to show
#We grab only the first 20 running processes to simplify our output
usersRunningPrograms=`ps -o"pid command" -U $usernameSelected | head -n 20`
lastLoginDate=`last -n 1 $usernameSelected | head -1 | tr -s '\t' ' ' | tr -s ' ' ' ' | cut -d' ' -f4-7`
usersHomeDirectory=`cat /etc/passwd | grep "^${usernameSelected}" | cut -d":" -f6`
sizeOfHomeDirectory=`du -ckh -d0 $usersHomeDirectory | grep "total" `

#Assemble this information into a big string and show it in an info box
usersInformation="You chose: ${usernameSelected} \n"
usersInformation="${usersInformation}Last Login: ${lastLoginDate} \n"
usersInformation="${usersInformation}Home Dir Size: ${sizeOfHomeDirectory} \n"
usersInformation="${usersInformation}Running Programs:\n\n ${usersRunningPrograms} "

infoBoxWidth=80
infoBoxHeight=30
dialog --msgbox "${usersInformation}" $infoBoxHeight $infoBoxWidth

#Re run ourselves
#HACK!
$0