#!/usr/bin/bash
################################################################
function usagemsg_fortune {
  echo "
Program: fortune

This script displays a fortune from either the file specified by 
the \"FileName\" parameter or by default from the \${HOME}/.fortunes
file.  After displaying the fortune, the fortune command exits. 

Usage: ${1##*/} [-?vVqdf] [-n #] [FileName ]
  Where:
    -v = Verbose mode - displays fortune file info
    -V = Very Verbose Mode - debug output displayed
    -q = Quiet mode - fortune not displayed
    -d = Data mode - displays the fortune file info in record format
    -f = Display the fortune number at the end of the fortune
    -n # = Display a specific fortune by it's numerical position 
           in the fortune data file

    FileName = FileName containing fortunes (Default: \${HOME}/.fortunes)

Author: Dana French (dfrench@mtxia.com) Copyright 2004
\"AutoContent\" enabled
"
}
################################################################
#### 
#### Description:
#### 
#### This script reads data from a "fortunes" formatted file
#### and writes a "stanza" of information from that file to
#### standard output.  Each stanza of information from the
#### "fortunes" file is delimited by a percent sign (%) on a
#### line by itself. 
#### 
#### Assumptions:
#### 
#### This script assumes the fortunes data file contains
#### lines of text, delimited into stanzas by a percent sign
#### (%) on a line by itself.  Each stanza represents a
#### "fortune" that is displayed randomly by this script.
#### 
#### Dependencies:
#### 
#### This script is dependent upon the unix utilities "grep",
#### "cut", and "sed".  These utilities must be in the PATH
#### in order for this script to work properly.
#### 
#### Products:
#### 
#### This script reads a data file and outputs a random stanza of
#### information from the data file.  Options to this script
#### can control which stanza is displayed, and information about
#### the randomly selected stanza.
#### 
#### Configured Usage:
#### 
#### This script can be executed from the command line,
#### startup script, or as a function from within another
#### script.  The most typical usage would be from a startup
#### script. 
#### 
#### Details:
#### 
################################################################
function fortune {
  typeset VERSION="1.1"
  typeset TRUE="1"
  typeset FALSE="0"
  typeset EXITCODE="0"
  typeset DATAMODE="${FALSE}"
  typeset QUIET="${FALSE}"
  typeset VERBOSE="${FALSE}"
  typeset VERYVERB="${FALSE}"
  typeset FORTBYNO="${FALSE}"
  typeset FORTNUMB="0"
  typeset FORTDISP="${FALSE}"
  typeset ARY
  typeset NUM

  while getopts ":vVqdfn#" OPTION
  do
      case "${OPTION}" in
          'n') FORTBYNO="${TRUE}"
               FORTNUMB="${OPTARG}";;
          'd') DATAMODE="${TRUE}";;
          'f') FORTDISP="${TRUE}";;
          'q') QUIET="${TRUE}";;
          'v') VERBOSE="${TRUE}";;
          'V') VERYVERB="${TRUE}";;
          '?') usagemsg_fortune "${0}" && exit 1 ;;
          ':') usagemsg_fortune "${0}" && exit 1 ;;
      esac
  done
   
  shift $(( ${OPTIND} - 1 ))
  
  typeset FORTFILE="${1:-${HOME}/.fortunes}"

  trap "usagemsg_fortune ${0}" EXIT
  if [[ "_${FORTFILE}" = "_" ]]
  then
    (( QUIET == FALSE )) &&
        echo "ERROR: Fortunes Filename not specified" >&2
    exit 3
  fi
  trap "-" EXIT
  
  (( VERBOSE  == TRUE )) && echo "# Version: ${VERSION}"
  (( VERYVERB == TRUE )) && set -x

################################################################

#### 
#### Check to see if the fortunes data file is readable, if not 
#### issue an error message and exit.
#### 

  if [[ ! -r ${FORTFILE} ]]
  then
    echo "# ERROR: Can't read fortunes FILE \"${FORTFILE}\"!" >&2
    return 1
  fi

#### 
#### Obtain a list of beginning line numbers for each
#### fortune.  Each fortune is delimited by a line beginning
#### with one or more "%".  Save the beginning line numbers
#### to an array for later use.
#### 

  ARY=( 1 $( egrep -n '^%%*[ 	]*' "${FORTFILE}" | cut -d: -f1 ) )

#### 
#### If there are no fortunes in the data file, issue an
#### error message and exit. 
#### 

  if (( ${#ARY[*]} == 0 ))
  then
    echo "# ERROR: No fortunes in FILE \"${FORTFILE}\"!" >&2
    return 2
  fi

####
#### Randomly select a fortune number by chosing and array element 
#### containing the beginning line number of a fortune from the data 
#### file.
####

  (( NUM = RANDOM % ${#ARY[*]} ))

####
#### If the -n option was specified on the command line, then compare the
#### fortune number specfied by the user against the number of fortunes in
#### the data file.  If the user specfied number is greater than the number
#### of fortunes in the data file, issue an error message and return with an
#### unsuccessful return code; otherwise set the fortune number to the
#### user specified number.
####

  if (( FORTBYNO == TRUE ))
  then
      if (( FORTNUMB < 0 )) || (( FORTNUMB > ( ${#ARY[*]} - 1 ) ))
      then
          echo "# ERROR: Invalid fortune number" >&2
          echo "# ERROR: Valid fortune numbers: 0 - $(( ${#ARY[*]} - 1 ))" >&2
          return 3
      fi
      NUM="${FORTNUMB}"
  fi

#### If VERBOSE mode is on, display some information about the
#### selected fortune.

  (( VERBOSE == TRUE )) && echo -E "# Fortune File: ${FORTFILE}"
  (( VERBOSE == TRUE )) && echo "# No. of fortunes in fortunes file: ${#ARY[*]}"
  (( VERBOSE == TRUE )) && echo "# Fortune No.: ${NUM}"
  (( VERBOSE == TRUE )) && echo "# Beginning line No.: ${ARY[NUM]}"

#### 
#### If the use specified DATA mode, display some information about
#### the selected fortune formatted as a data record separated by 
#### colon ":" delimeters.  The fortune itself is not displayed.
#### 

  if (( DATAMODE == TRUE ))
  then
      echo "# fortfile:fortcnt:fortnumb:fortline" >&2
      echo -E "${FORTFILE}:${#ARY[*]}:${NUM}:${ARY[NUM]}"
      return 0
  fi

#### If QUIET mode was specified by the user on the command line,
#### do not display the fortune, simply return with a successful
#### return code.

  (( QUIET == TRUE )) && return 0

#### 
#### Display one single fortune by using beginning line number of
#### the fortune and displaying all lines until the next
#### fortune delimeter "%" is found, or end of file.
#### 

  (( FORTDISP == TRUE )) && echo "Fortune ${NUM} of ${#ARY[*]}"
  sed -e "${ARY[NUM]},/^%%*[ 	]*$/ !d;s/^%.*//" "${FORTFILE}"

 return 0
}
################################################################

fortune "${@}"