#!/bin/bash
#
# CIS 130 Midterm
#
# Rich Simms
# Spring 2007
#
# This script is a ls command for directoreis
#
# usage: lsd [-dla] [path1] [path2] ... [pathn]
#
#            path - path to the location of the directories
#            d - debug tracing
#            l - long listing
#            a - show hidden directories
#

# Initialize
usage="lsd [-dla] [path1][path2] ... [pathn]"
TRUE=1
FALSE=""
trace=$FALSE
long=$FALSE
hidden=$FALSE
result=0

# Process options
while getopts ":dla" opt; do
  case $opt in
     d) trace=$TRUE ;;
     l) long=$TRUE ;;
     a) hidden=$TRUE ;;
     *) echo "-- Usage: " $usage >&2
        exit 1 ;;
  esac
done

# Debug tracing to verify options
[ $trace ] && echo "trace=$trace"
[ $trace ] && echo "long=$long"
[ $trace ] && echo "hidden=$hidden"

#ls args: l=long, a=show hidden, L=show linked file types
arg="lL"
if [ $hidden ]; then arg="lLa"; fi

# Shift out any options
if [ $OPTIND -ge 1 ]; then shift $(($OPTIND - 1)); fi

if [ $# -eq 0 ]; then path="$(pwd)"; fi
if [ $# -gt 1 ]; then multiple=$TRUE; fi

# Get first path
path=$1

# If not path specified default to current directory
if [ "$path" = "" ]; then path="$(pwd)"; fi
while [ $path ]
do
   [ $trace ] && echo "path=$path"
   # Check if it is a directory
   if ! [ -d $path ]; then
      echo "$path is not a directory." >&2
      result=1
   # Check for read access
   elif ! [ -r $path ]; then
      echo "$path: permission denied." >&2
      result=2
   # If more than one path, print path and indent, otherwise just list directories
   elif [ $multiple ]; then
      echo "$path:"
      if [ $long ]; then
         # Long listing of directories indented
         ls -$arg $path | grep '^d.*' | sed -e 's/\(^.*\)\( \)\(.*$\)/     \1\2\3/g'
      else
         # Just directory name indented
         ls -$arg $path | grep '^d.*' | sed -e 's/\(^.*\)\( \)\(.*$\)/     \3/g'
      fi
   else
      if [ $long ]; then
         # Long listing of directories
         ls -$arg $path | grep '^d.*'
      else
         # Short listing of directories
         ls -$arg $path | grep '^d.*' | sed -e 's/\(^.*\)\( \)\(.*$\)/\3/g'
      fi
   fi
   shift
   path=$1
done
exit $result