#!/bin/bash
#===================================================================================
#
#   FILE: lottery.sh 
#
#   USAGE: ./lottery.sh
#
# DESCRIPTION: Generate 5 random numbers between 1 and 50 and two random
#              lucky numbers between 1 and 11 to be used in the UK Euromillions lottery. 
#              The 5 normal numbers are picked using the following format to give an even 
#              spread:
#              * 1 number between 1 to 50
#              * 2 numbers between 1 and 25
#              * 2 numbers between 26 to 50   
#
#      OPTIONS: --- 
# REQUIREMENTS: ---
#         BUGS: ---
#        NOTES: ---
#       AUTHOR: --- 
#      COMPANY: ---
#      VERSION: --- 
#      CREATED: ---  
#     REVISION: --- 
#===================================================================================

#=== FUNCTION ================================================================
#        NAME: check_number
# DESCRIPTION: checks number passed to it that it doesn't exist in array 
# PARAMETER 1: Boolean variable to say if it exists or not
# PARAMETER 2: Number to be checked in array
#===============================================================================
check_number() {
  local  __check_number=$1
  local lottery_number=$2
  local x

  for ((x = 0; x < ${#lottery[@]} ; x ++ ))  
  do 
    if [ ${lottery[$x]} -eq $lottery_number ]
    then
      eval $__check_number=true
    fi
  done
}

#=== FUNCTION ================================================================
#        NAME: generate_main_number
# DESCRIPTION: Generate main lottery numbers, ensure there are no duplicates 
#              and put in array
# PARAMETER 1: lottery number that is to be passed back 
# PARAMETER 2: Type of number which determines which range it will be in ie. 
#              either between 1 and 25 or between 26 and 50 
#===============================================================================
generate_main_number() {
  local number

  number_type=$1

  number_picked=false
  until $number_picked ; do 
    if [ $number_type == "First" ]
    then    
      number=$(( $RANDOM % 24 + 1 ))
    else
      number=$(( $RANDOM % 24 + 26 ))
    fi
    number_exists=false
    check_number number_exists $number
    if ! $number_exists
    then
      return $number 
      number_picked=true
    fi 
  done
}

#=== FUNCTION ================================================================
#        NAME: main 
# DESCRIPTION: Main function to drive program 
# PARAMETER 1: ---
#===============================================================================
main () {
  local x
  # Generate first number
  lottery[0]=$(( $RANDOM % 49 +1 ))

  # Generate second and third lottery main number betwen one and fifty
  for ((x = 0; x <= 1 ; x ++ ))  
  do
    generate_main_number "First"
    lottery[1+$x]=$?
  done

  # Generate forth and fifth lottery main number between one and fifty
  for ((x = 0; x <= 1 ; x ++ ))  
  do
    generate_main_number "Second"
    lottery[3+$x]=$?
 done

  # Generate 2 lucky numbers ensuring they are two different numbers
  lottery[6]=$(( $RANDOM % 10 +1 )) 
  correct_number=false
  until  $correct_number ; do 
    lottery[7]=$(( $RANDOM % 10 +1 )) 
    if [ ${lottery[6]} -ne ${lottery[7]} ] 
    then
      correct_number=true
    fi
  done

  # display lottery number
  echo ${lottery[@]}
}

# Calls main function to start program
main