#!/bin/bash
###########################################################################
#
# rove Version 0.4
#
# Designed to allow you to recurse over a selected set of directories and
# execute any given command from that directory.  Please note that complex
# commands require extensive knowledge of shell metacharacter escapement.
#
# Written by Jeff Albro <jeff@antistatic.com>, with pointers from Patrick
# Jordan <patrick@antistatic.com>.
#
# Copyright 2002, Jeff Albro, Liscensed under the GNU GPL, Version 2.
#
# See www.gnu.org for details.
#
# Compatability:
#
# May need minor tweaks to run under ksh.  Should run fine under sh if
# getopts exists.  Getopt can be used instead, but it is less robust.
#
# To do:
#
# Allow for preexecution queries
# Add provsion for dealing with hidden directories.
#
###########################################################################

#####################################
# some global information

version="0.4"

############################################
# function to clue the user in, then exit...

echo_usage ()
{
cat <<EOF

rove $version, by Jeff Albro <jeff@antistatic.com>

Usage:
        rove [-ce#fils#tvw] start-directory [command]

Options:
        -c      check command before executing (recommended)
        -e#     end level (level 0 is the start directory)
        -f      follow symbolic links
        -i      interactive (implies -c)
        -l      leaves only (execute in directories without subdirectories)
        -s#     start level (level 0 is the start directory)
        -t      top down (default is bottom up)
        -v      verbose
        -w      wood only (execute in directories with subdirectories)

Warning:
        Be sure to escape metacharacters such as $<>&|(); with a \ or by
        quoting to bypass intial shell evaluation, if desired.  Use -c
        for pre-confirmation.

EOF

exit $1
}

################################################
# determine if a directory has no subdirectories

leaf ()
{
if [ -z "$(command find $1 -mindepth 1 -maxdepth 1 -type d)" ]; then
        return 0
else
        return 1
fi
}

##########################################################
# determine if a directory has at least one subdirectories

wood ()
{
if [ -n "$(command find $1 -mindepth 1 -maxdepth 1 -type d )" ]; then
        return 0
else
        return 1
fi
}

####################
# begin main program

opt_command=""
opt_end=""
opt_end_level=""
opt_followlinks=""
opt_interactive=""
opt_leaves=""
opt_start=""
opt_start_level=""
opt_top_down="-depth"
opt_verbose=""
opt_wood=""

################################
# need to save starting location

start=$PWD

#################
# process options

while getopts ":ce:fils:tvw" opt
do
        case $opt in

        c) opt_command="TRUE";;
        e) opt_end="-maxdepth"; opt_end_level="$OPTARG";;
        f) opt_followlinks="-follow";;
        i) opt_interactive="TRUE"; opt_command="TRUE";;
        l) opt_leaves="TRUE";;
        s) opt_start="-mindepth"; opt_start_level="$OPTARG";;
        t) opt_top_down="";;
        v) opt_verbose="TRUE";;
        w) opt_wood="TRUE";;
        ?) echo_usage 1;;

        esac
done

shift $(($OPTIND - 1))


#################################
# time out for error checking

if [ $# = 0 ]; then
        echo_usage 1
fi

if [ -n "$opt_wood" ] && [ -n "$opt_leaves" ]; then
        echo_usage 1
fi


#################################
# continue preprocessing

findstart=$1

shift

command=$@


#############################
# print the command

if [ -n "$opt_verbose" ] || [ -n "$opt_command" ]; then
        if [ -n "$command" ]; then
                echo
                echo "\"$command\" will be executed in each processed directory"
                echo
        else
                echo
                echo "No commands to be executed"
                echo
        fi
fi


if [ -n "$opt_command" ]; then

        #query user
        while [ true ]; do
                echo -n "Is this what you want? (Y/n) "
                read answer

                if [ "$answer" = "n" ] || [ "$answer" = "N" ]; then
                        echo
                        echo "exiting..."
                        echo
                        exit 1
                elif [ "$answer" = "Y" ] || [ "answer" = "y" ] || [ -z "$answer" ]; then
                        echo
                        echo "continuing..."
                        echo
                        break
                else
                        echo
                        echo "Invalid answer, please try again..."
                        echo
                fi
        done
fi

##################################
# get unfiltered directory listing

preliminary_list=$(command find $findstart $opt_followlinks $opt_start $opt_start_level $opt_end $opt_end_level $opt_top_down -type d)

##############################
# filter preliminary_list here

if [ -n "$opt_leaves" ]; then
        for directory in $preliminary_list; do
                if leaf $directory; then
                        directory_list="$directory_list $directory"
                fi
        done

elif [ -n "$opt_wood" ]; then
        for directory in $preliminary_list; do
                if wood $directory; then
                        directory_list="$directory_list $directory"
                fi
        done
else
        directory_list=$preliminary_list
fi

#####################
# process directories

for directory in $directory_list; do

        if [ -n "$opt_interactive" ]; then

                #query user
                while [ true ]; do

                        echo -n "Process $directory? (Y/n/q) "
                        read answer

                        if [ "$answer" = "y" ] || [ "$answer" = "Y" ] || [ -z "$answer" ]; then
                                command cd $directory
                                eval $command
                                command cd $start
                                break
                        elif [ "$answer" = "n" ] || [ "$answer" = "N" ]; then
                                break
                        elif [ "$answer" = "q" ] || [ "$answer" = "Q" ]; then
                                echo
                                echo "exiting..."
                                echo
                                exit 1
                        else
                                echo
                                echo "Invalid answer, please try again..."
                                echo
                        fi
                done

        elif [ -n "$opt_verbose" ]; then

                echo "Processing $directory"

                command cd $directory
                eval $command
                command cd $start

        else
                command cd $directory
                eval $command
                command cd $start
        fi

done

##################
#exit successfully

exit 0

##################
# end of rove