#!/bin/sh
#
# make_disc_trees
#
# From the list of packages we have, lay out the CD trees

set -e

BASEDIR=$1
MIRROR=$2
TDIR=$3
CODENAME=$4
ARCHES=$5
MKISOFS=$6

LIST=$TDIR/list
LIST_EX=$TDIR/list.exclude

DISKNUM=1
MAX_DONE=0

BDIR=$TDIR/$CODENAME
LOG=$BDIR/make_disc_tree.log

MiB=1048576
MB=1000000
BLOCKSIZE=2048

# Calculate the maximum number of 2K blocks in the output images
case $DISKTYPE in
	BC)
		MAXDISKBLOCKS=`echo "680 * $MB / $BLOCKSIZE" | bc`
		DISKDESC="businesscard"
		;;
	NETINST)
		MAXDISKBLOCKS=`echo "680 * $MB / $BLOCKSIZE" | bc`
		DISKDESC="netinst"
		;;
	*CD)
		MAXDISKBLOCKS=`echo "680 * $MB / $BLOCKSIZE" | bc`
		DISKDESC="650MiB CD"
		;;
	CD700)
		MAXDISKBLOCKS=`echo "737 * $MB / $BLOCKSIZE" | bc`
		DISKDESC="700MiB CD"
		;;
	DVD)
		MAXDISKBLOCKS=`echo "4700 * $MB / $BLOCKSIZE" | bc`
		DISKDESC="4.7GB DVD"
		;;
	CUSTOM)
		MAXDISKBLOCKS=$CUSTOMSIZE
		DISKDESC="User-supplied size"
		;;
esac

export MAXDISKBLOCKS DISKDESC

# Cope with HFS-hybrid disks using extra space for the HFS metadata
case "$ARCHES" in
	*m68k*|*powerpc*) SIZE_CHECK_PERCENT="90 / 100";;
	*)                SIZE_CHECK_PERCENT="95 / 100";;
esac

# How full should we let the disc get before we stop estimating and
# start running mkisofs?
SIZE_SWAP_CHECK=`echo "$MAXDISKBLOCKS * $SIZE_CHECK_PERCENT" | bc`

PKGS_THIS_CD=0
PKGS_DONE=0
SIZE=0
OVERFLOWPKG=""
MKISOFS_CHECK="$MKISOFS -r -print-size -quiet"

#############################################
#
#  Local helper functions
#
#############################################
check_base_installable () {
	ARCH=$1
	CDDIR=$2
	ok=0

	for p in `debootstrap --arch $ARCH --print-debs $CODENAME $TDIR/debootstrap.tmp file:$MIRROR $DEBOOTSTRAP_SCRIPT 2>/dev/null`
	do
		if ! grep -q "^Package: $p$" $CDDIR/dists/$CODENAME/main/binary-$ARCH/Packages 2>/dev/null; then
			if [ -n "$BASE_EXCLUDE" ] && grep -q ^$p$ $BASE_EXCLUDE ; then
				echo "Missing debootstrap-required $p but included in $BASE_EXCLUDE" >> $LOG
				continue
			fi
			ok=$(($ok + 1))
			echo "Missing debootstrap-required $p" >> $LOG
		fi
	done
	rm -rf $TDIR/debootstrap.tmp
	echo $ok
}

finish_disc () {
	CDDIR=$1
	NOT=$2

	if [ $DISKNUM = 1 ] ; then
		for ARCH in $ARCHES_NOSRC
		do
			echo "  Checking base is installable for $ARCH" 
			ARCHOK=`check_base_installable $ARCH $CDDIR`
			if [ $ARCHOK -gt 0 ] ; then
				echo "  $ARCH is missing $ARCHOK files needed for debootstrap, look in $LOG for the list"
			fi
			ok=$(($ok + $ARCHOK))
		done
		if [ $ok = 0 ] ; then
			touch $CDDIR/.disk/base_installable
			echo "  all files needed for debootstrap"
		else
			echo "  $ok files missing for debootstrap, not creating base_installable"
			if [ "$DISKTYPE"x = "BC"x ] ; then
			    echo "  This is expected - building a BC"
			fi
		fi
		echo "$ok files missing for debootstrap" >> $LOG
	fi

	echo "  Finishing off md5sum.txt"
	cd $CDDIR
	# Just md5 the bits we won't have seen already
	find ./.disk ./dists -type f | xargs md5sum >> md5sum.txt
	# And sort; it should make things faster for people checking
	# the md5sums, as ISO9660 dirs are sorted alphabetically
	LANG=C sort -uk2 md5sum.txt > md5sum.txt.tmp
	mv -f md5sum.txt.tmp md5sum.txt
	cd $BDIR

	SIZE=`$SIZE_CHECK $CDDIR` 
	BYTES=`echo "$SIZE * 2048" | bc`
	echo "CD #$DISKNUM $NOT filled with $PKGS_THIS_CD packages, $SIZE blocks, $BYTES bytes" >> $LOG
	echo "  CD #$DISKNUM $NOT filled with $PKGS_THIS_CD packages, $SIZE blocks, $BYTES bytes"
	date >> $LOG
}

cd $BDIR

# Size calculation is slightly complicated:
#
# 1. At the start, ask mkisofs for a size so far (including all the
#    stuff in the initial tree like docs and boot stuff
#
# 2. After that, add_packages will tell us the sizes of the files it
#    has added. This will not include directories / metadata so is
#    only a rough guess, but it's a _cheap_ guess
#
# 3. Once we get >90% of the max size we've been configured with,
#    start asking mkisofs after each package addition. This will
#    be slow, but we want to be exact at the end

echo "Starting to lay out packages into $DISKTYPE ($DISKDESC) images: $MAXDISKBLOCKS 2K-blocks maximum per image"

for PKG in `cat $BDIR/packages` # | head -2000`
do
	CDDIR=$BDIR/CD${DISKNUM}
    if [ ! -d $CDDIR ] ; then
		if [ "$MAXCDS"x != ""x ] && [ $DISKNUM -gt $MAXCDS ] ; then
			echo "Disk #$DISKNUM is beyond the configured MAXCDS of $MAXCDS; exiting now..."
			MAX_DONE=1
			break
		fi
		echo "Starting new disc $DISKNUM at "`date` >> $LOG
		start_new_disc $BASEDIR $MIRROR $TDIR $CODENAME "$ARCHES" $DISKNUM

		echo "  Starting the md5sum.txt file"
		# Grab all the early stuff, apart from dirs that will change later
		cd $CDDIR && \
			find . -type f | grep -v -e ^\./\.disk -e ^\./dists | \
			xargs md5sum > md5sum.txt && \
			cd $BDIR

		echo "  Placing packages into image $DISKNUM"
		MKISOFS_OPTS=`cat $BDIR/$DISKNUM.mkisofs_opts` || true
		MKISOFS_DIRS=`cat $BDIR/$DISKNUM.mkisofs_dirs` || true
		SIZE_CHECK="$MKISOFS_CHECK $MKISOFS_OPTS $MKISOFS_DIRS"
		SIZE=`$SIZE_CHECK $CDDIR`
		echo "CD #$DISKNUM: size is $SIZE before starting to add packages" >> $LOG
		if [ "$OVERFLOWPKG"x != ""x ] ; then
			echo "Starting with the package that failed on the last disc: $OVERFLOWPKG" >> $LOG
			GUESS_SIZE=`add_packages $CDDIR $OVERFLOWPKG`
			SIZE=$(($SIZE + $GUESS_SIZE))
			echo "CD #$DISKNUM: GUESS_TOTAL is $SIZE after adding $OVERFLOWPKG" >> $LOG
			OVERFLOWPKG=""
			PKGS_THIS_CD=1
			PKGS_DONE=$(($PKGS_DONE + 1))
		fi
	fi

	GUESS_SIZE=`add_packages $CDDIR $PKG`
	SIZE=$(($SIZE + $GUESS_SIZE))
	echo "CD #$DISKNUM: GUESS_TOTAL is $SIZE after adding $PKG" >> $LOG
	if [ $SIZE -gt $SIZE_SWAP_CHECK ] ; then
		SIZE=`$SIZE_CHECK $CDDIR` 
		echo "CD #$DISKNUM: Real current size is $SIZE blocks after adding $PKG" >> $LOG
	fi
	if [ $SIZE -gt $MAXDISKBLOCKS ] ; then
		echo "CD #$DISKNUM over-full. Rollback!" >> $LOG
		GUESS_SIZE=`add_packages --rollback $CDDIR $PKG`
		SIZE=`$SIZE_CHECK $CDDIR` 
		echo "CD #$DISKNUM: Real current size is $SIZE blocks after rolling back $PKG" >> $LOG

		finish_disc $CDDIR ""
		# Put this package first on the next disc
		OVERFLOWPKG=$PKG
		# And reset, to start the next disc
		SIZE=0
		DISKNUM=$(($DISKNUM + 1))		
	else
		PKGS_THIS_CD=$(($PKGS_THIS_CD + 1))
		PKGS_DONE=$(($PKGS_DONE + 1))
	fi
	
done

if [ "$MAX_DONE" = 0 ] ; then
	finish_disc $CDDIR "(not)"
fi

echo "Finished: $PKGS_DONE packages placed" >> $LOG
echo "Finished: $PKGS_DONE packages placed"
BYTES=`echo "$SIZE * 2048" | bc`
date >> $LOG