#!/bin/sh

set -e
# garbage collect a package database
# flags to skip phases

# -C clear all phases
# -n dry run
# -a all phases
# default is failed packages, orphaned elf, vacuum
# 
# only affect files with the status in the list
status=
# phases
# -cC remove command history by date
remove_command_history=
# -dD remove dry run
remove_dry_run=1
# -eE remove orphaned elf
remove_orphaned_elf=1
# -fF remove failed
remove_failed=1
# -hH fix file content hash
remove_incomplete_packages=0
fix_hash=0
# -hH remove install history by date
remove_history=
# -lL remove old logs, given by date
remove_logs=
# -nN remove acked notes
remove_acked_notes=0
# -pP remove history for missing packages
clean_missing_package_history=0

# -hH remove all file content that is not scripts or configs
remove_packagefile_content=1
remove_script_content=1
remove_config_content=1
# -rR remove removed packages, unless preserved
remove_removed_packages=0

# -vV compactify the database file
vacuum=0

# remove orphaned rows in files table packagefiles, notes, scripts, ...
unreferenced_file_content=1

# remove outdated packages, unless preserved
remove_old_packages=1

db=${ZPMDB:-/var/lib/zpm/local.db}

retain_old=${ZPM_KEEP_PACKAGES:-2}

while getopts 'f:PcCk:' opt; do
	case $opt in
		f) db="$OPTARG" ;;
		P) remove_old_packages=0 ;;
		c) vacuum=1 ;;
		C) unreferenced_file_content=0 ;;
		k) retain_old="$OPTARG" ;;
	esac
done

retain_old=$((retain_old + 0))
if [ $retain_old -le 0 ]; then
	retain_old=0
fi

if [ -z "$db" ]; then
	echo must specify database file
	exit 1
fi

ZPMDB=$db
export ZPMDB

# check for incorrect hash file content

# remove orphaned elf info

# remove failed packages
for pkg in $(zpm list -s failed); do
	zpm rmpackage -m 'gc removed failed' "$pkg"
	echo removed $pkg
done

for pkg in $(zpm list -s dryrun); do
	zpm rmpackage -m 'gc removed dryrun' "$pkg"
	echo removed $pkg
done

# remove incomplete packages
# TODO use temporary gc delete log trigger?
if [ $remove_incomplete_packages -ne 0 ]; then
	for pkg in $(zpm list -F 'hash is null'); do
		zpm rmpackage -m 'gc removed incomplete' $pkg
	echo removed $pkg
	done
fi

# remove old version packages, unless preserved
# remove removed packages, unless preserved
if [ $remove_old_packages -ne 0 ]; then
	zpm shell $ZPMDB "select printf('%s-%s-%s',package,version,release) from package_age where age > $retain_old" | while read pkg; do
	zpm rmpackage -m 'gc removed old package' $pkg
	echo removed $pkg
done
fi

# remove orphaned rows in files table
# references in packagefiles, notes, scripts, possibly others

if [ $remove_orphaned_files -ne 0 ]; then
	count=$(zpm shell $ZPMDB 'delete from files where hash in (select hash from filerefs where refcount = 0);select changes()')
	if [ $count -gt 0 ]; then
		zpm log -v -i -a 'gc' -t $ZPMDB "removed $count unreferenced content"
	fi
fi

# remove old logs, given by date

# remove acked notes
if [ $remove_acked_notes -ne 0 ]; then
	zpm shell $ZPMDB 'delete from notes where ack != 0'
fi

# remove install history by date

# remove history for missing packages
if [ $clean_missing_package_history -ne 0 ]; then
	# delete from zpmlog where ?
	true
fi

# remove command history by date

# compactify the database file
if [ $vacuum -ne 0 ]; then
	osize=$(zpm stat -f '%s' $ZPMDB)
	zpm shell $ZPMDB vacuum
	nsize=$(zpm stat -f '%s' $ZPMDB)
	zpm log -v -i -a 'gc compacted' -t $ZPMDB "$osize -> $nsize"

	printf 'original size %s\n' $osize
	printf 'new size %s\n' $nsize
fi