#!/bin/bash
# Author: Joshua Bailey
# Script: divApp2
# This script takes the first argument you entered
# and writes to a file with that name.
# If it exists it prompts to append, overwrite, or exit
# It then opens the other file names you pass it to redirect
# Their output for the first files input.
# syntax: divApp2 fileAddTo addFrom1 addFrom2 addFrom3 ....

# function printBeginning
printBeginning ()
{
   # append a line break
   echo "================================================================" >> $1

   # append begin
   echo "               <*** Begin \"$2\" ***>" >> $1

   # space holder
   echo " " >> $1
} # end function printBeginning

# function printEnding
printEnding ()
{
   # space holder
      echo " " >> $1

      # append the end of file line break
      echo "               <*** End \"$2\" ***>" >> $1
      echo "================================================================" >> $1

      # space holder
                echo " " >> $1
      echo " " >> $1
} # end function printEnding

# function argumentCheck
argumentCheck ()
{
   # check to see if user used enough arguments
   if [[ ! $1 > 1 ]]
   then
      # tell the user that the syntax was entered incorrectly
      echo "*** Error: too few arguments!"
      echo "*** Must have a file to append to or create."
      echo "*** Must also have atleast one file to read from."
      echo "*** Syntax: divApp2 fileAddTo addFrom1 addFrom2 addFrom3..."
      exit
   fi
} # end function argumentCheck

# function existFileAddTo
existFileAddTo ()
{
   if [[ -e $1 ]]
   then

      # if it exists say so
      echo "File \"$1\" already exists."

      # ask user what they want to do
      read -p "Do you want to append, overwrite, or exit? (a|o|e) " ans

      # make sure the variable holds the correct case
      ans=`echo $ans | tr [:upper:] [:lower:]`

      # use only the first letter to decide what to do
      ans=${ans:0:1}

      # do what the user requested
      if [[ $ans = "e" ]]
      then
         echo "*** Exiting ***"
         exit
      elif [[ $ans = "o" ]]
      then
         echo "*** Overwriting ***"
         rm -f $1
         ans="T"
      elif [[ $ans = "a" ]]
      then
         echo "*** Appending ***"
         ans="T"
      else
         if [[ $ans != "T" ]]
         then
            echo "That choice is not an option!"
            echo "*** Exiting ***"
            exit
         fi
      fi
   fi
} # end function existFileAddTo

# function viewFile
viewFile ()
{
   read -p "Do you want to display the file? (y|n) " YesNo

   # make user input lower case
   YesNo=`echo $YesNo | tr [:upper:] [:lower:]`

   # cut off all except the first letter
   YesNo=${YesNo:0:1}

   if [[ $YesNo = "y" ]]
   then

      # display the file
      cat $1 | less
   fi
} # end function viewFile

# assign the first parameter (the created file) to copyTo
copyTo=$1

# assign the number of parameters to loopCount
loopCount=$#

# declare the array
declare -a arr

# check to see if user used enough arguments
argumentCheck $loopCount

# assign the arguments to an array
for ((i=0; i != ($loopCount-1); i++))
do
   arr[$i]=$2
   shift 1

   # see if all files listed exist...exit if they don't
   if [[ ! -e ${arr[$i]} ]]
   then
      echo "File \"${arr[$i]}\" does not exist, or you typed the wrong path!"
      echo "*** Aborting ***"
      exit
   fi
done

   # see if the fileAddTo file exists or not
   existFileAddTo $copyTo

   # loop the appending the number of parameters minus one (the first one)
   for ((i=0; i < `echo ${#arr[*]}`; i++))
   do

      printBeginning $copyTo ${arr[$i]}
   
      # append the contents of the file you specified
      cat ${arr[$i]} >> $copyTo

      printEnding $copyTo ${arr[$i]}

   done

   # state that the process is complete
   echo "*** Done ***"

   # see if user wants to view the file created
   viewFile $copyTo

todaytag=`date`
divApp2 logfiletomake.$todaytag logfile1 logfile2 logfile3...