#!/bin/bash
#
#  Synchronize several httpup repositories to a centralized collection.
#

. /etc/prtsync.conf

#  Print $1 to stderr and exit.
error(){
	echo "=======> ERROR: $1" >&2
	exit 1
}

#  Ensure $1 is a directory and is readable or writeable, depending 
#  on the optional parameter $2.  Exit if conditions are not met.
ensure_path(){
	if [ ! -d "$1" ]; then
		error "$1 is not a directory."
	elif [ "$2" = "r" -a ! -r "$1" ]; then
		error "$1 is not readable."
	elif [ "$2" = "w" -a ! -w "$1" ]; then
		error "$1 is not writeable."
	fi
}

#  Sends a Cc notification email to address(es) $1 with subject $2 
#  and body $3.  Mails are always sent to $mailer.
notify(){
	/usr/sbin/sendmail -t -f$mailer <<-EOF
	To: $mailer
	`for recipient in $1; do echo Cc: $recipient; done`
	Subject: $2	
	
	$3
	
	Please rectify the problem.
EOF
}

#  Iterates the collection $1, tagging and untagging all ports.
tag_untag_ports(){
	
	echo "Tagging ports in $1..";
	
	ports=`find $1 -mindepth 1 -type d | sort`
	for port in $ports; do  #tag or untag based on prompt
	
		prompt="y/N"; default="n"
			
		if [ -f $port/.sync ]; then  #resolve default
			prompt="Y/n"; default="y"
		fi
	
		p=`basename $port`; echo -n "$p [$prompt]: "
		read c; test "$c" || c=$default
		
		if [ "$c" = "y" -o "$c" = "Y" ]; then
			tagged="$tagged $p "
			touch $port/.sync
		else
			untagged="$untagged $p "
			rm -f $port/.sync
		fi
	
	done
	
	httpup-repgen $1 >/dev/null
	
	echo "  Tagged:   $tagged" | sed 's/  /\n/g'
	echo "  Untagged:   $untagged" | sed 's/  /\n/g'	
}

#  Syncs collections defined in $1 to $2, notifying appropriate parties 
#  of errors and removing ports without .sync files.
sync_ports(){
	
	echo "Syncing collections in $1 to $2.." 
	
	for driver in $1/*.httpup; do  #parse driver file, sync repo
		
		email=`fgrep "EMAIL=" $driver | sed "s/EMAIL=//"`
		url=`fgrep "URL=" $driver | sed "s/URL=//"`
		collection=`basename $driver .httpup`
		
		if httpup sync $url $2/$collection >/dev/null 2>&1; then
			synced="$synced $collection "
		else  #notify of failure
			notify "$email" "Sync failed for $collection" "" 
			failed="$failed $collection "
		fi		
	done
	
	echo "  Synced:   $synced" | sed 's/  /\n/g'
	echo "  Failed:   $failed" | sed 's/  /\n/g'
}

#  Merges ports in $2 to $3, notifying of any duplicates.  Notifications are 
#  made to addresses specified in the collections defined in $1.  In the 
#  event of a duplicate, the last stable version of a port from the attic $4
#  is used if available.
merge_ports(){
	
	echo "Merging ports in $2 to $3.."
	
	mv $3/.current $3/.prev 2>/dev/null
	
	if [ "$ignore_tag_files" = "true" ]; then  #merge all ports
		ports=`find $2 -mindepth 2 -type d | sort`
	else  #or only tagged ones
		ports=`find $2 -mindepth 3 -name .sync | sed 's|/\.sync||' | sort`
	fi
		
	for port in $ports; do  #prune duplicates, notify affected parties
		
		p=`basename $port`
		
		echo "$duplicated" | grep " $p " >/dev/null && continue
		paths=`echo "$ports" | grep "/$p$"`
		
		if [ `echo "$paths" | wc -l` -gt 1 ]; then  #duplicate found, notify
						
			drivers=`echo -e "\n\n$paths" | sed "s|^$2/|$1/|; s|/$p|.httpup|g"`
			emails=`fgrep -h "EMAIL=" $drivers | sed "s/EMAIL=//g"`
			
			notify "$emails" "Duplicate port $p" "Port $p found in:$drivers"
			duplicated="$duplicated $p "
			
			test -d $4/$p && port=$4/$p || continue  #use attic or skip
		fi
		
		test -d $base/$p -o -d $opt/$p || cp -r $port $3
		echo $p >>$3/.current
	
	done
				
	if [ -f $3/.current ]; then  #generate REPO, ignoring archive
		echo "TARBALL" > $3/.httpup-repgen-ignore
		httpup-repgen $3 >/dev/null
		
		if [ "$use_archive" = "true" ]; then  #update archive
			cd $3; tar zcf $2/TARBALL .
			mv $2/TARBALL $3; cd -
		fi
	fi
		
	if [ -f $3/.prev ]; then  #resolve added/removed	
		added=`diff $3/.prev $3/.current | grep '>'`
		removed=`diff $3/.prev $3/.current | grep '<'`
	else  #no .prev, all ports were added
		added=`cat $3/.current 2>/dev/null`
	fi
	
	echo "  Added:  $added" | sed 's/  /\n/g; s/> //g'
	echo "  Removed:  $removed" | sed 's/  /\n/g; s/< //g'
	echo "  Duplicated:   $duplicated" | sed 's/  /\n/g'
	echo	
}

#
#    Execution begins.  Process arguments and dispatch function calls.
#

test "$1" = "-i" && ignore_tag_files="true" && shift
test "$1" = "-a" && use_archive="true" && shift

case $1 in
	"tag")  #client mode, tag/untag ports in $2 or pwd
		collection=$2; test -d $collection || collection=`pwd`
		
		ensure_path $collection "w"
		
		tag_untag_ports $collection
		;;
	
	"sync")  #sync repos to $work, notify of errors
		mkdir -p $work; ensure_path $work "w"
		ensure_path $collections "r"				
		
		sync_ports $collections $work
		;;
		
	"merge")  #merge ports in $work to a clean $destination
		ensure_path $collections "r"
		ensure_path $work "r"
		ensure_path $base "r"
		ensure_path $opt "r"
		
		mkdir -p $destination; ensure_path $destination "w"
		mkdir -p $attic; ensure_path $attic "w"
		
		export GLOBIGNORE="TARBALL:.*"  #keep archive and dotfiles
		
		chmod 700 $destination $attic  #drop permissions for merge		
		(cd $destination; mv -f * $attic 2>/dev/null)
				
		merge_ports $collections $work $destination $attic
		chmod 755 $destination $attic  #and then restore them
		;;
	*)  #show usage and exit
		echo "Usage: prtsync [options] command" >&2
		exit 1
		;;
	
esac

exit 0

#End of file