#!/bin/bash

MAX_VERSIONS=5

BASE_DIR="/home/backy/sw-backups"

DB_BACKUPS="$BASE_DIR/db"
DIR_BACKUPS="$BASE_DIR/dir"

MODE="0600"
OWNER="backy"
EXCLUDE_LIST="/etc/backup.exclude"

mkdir -p "$DB_BACKUPS" "$DIR_BACKUPS"
chown -R "$OWNER" "$DB_BACKUPS" "$DIR_BACKUPS"

rotate(){
	local dir="$1"
	local pattern="$2"
	local versions="$3"

	local files=($(find "$dir" -name "$pattern" -printf "%C@ %p\n" | sort -n | cut -d' ' -f2-))
	while [[ "${#files[@]}" -ge "$versions" ]]
	do
		rm -rf "${files[0]}"
		unset files[0]
		backups=( "${files[@]}" )
	done
}

store_compressed(){
	local dir="$1"
	local name="$2"
	local ext="$3"
	local versions="$4"
	shift 4

	local tmpfile="`mktemp`"

	$@ | bzip2 -9 -c > "$tmpfile"

	[[ "${PIPESTATUS[0]}" -eq 0 ]] || {
		rm -f "$tmpfile"
		return 1
	}

	rotate "$dir" "${name}_*$ext" "$versions"

	local bname="$dir/${name}_`date +"%d.%m.%Y_%H.%M"`.$ext"
	mv "$tmpfile" "$bname" || {
		rm -f "$tmpfile"
		return 1
	}

	chmod "$MODE" "$bname"
	chown "$OWNER" "$bname"
}

backup_db(){
	local dbname="$1"
	local user="$2"
	local password="$3"

	store_compressed "$DB_BACKUPS" "$dbname" "sql.bz2" "$MAX_VERSIONS" mysqldump -u "$user" --password="$password" -B "$dbname"
}

backup_dir(){
	local dir="$1"
	local parent="`dirname "$dir"`"
	local fname="`basename "$dir"`"

	store_compressed "$DIR_BACKUPS" "$fname" "tar.bz2" "$MAX_VERSIONS" tar -X "$EXCLUDE_LIST" -C "$parent" -cf - "$fname"
}

backup_db dbname dbuser dbpassword
backup_db dbname dbuser dbpassword

backup_dir /home/site1/public_html
backup_dir /home/site1/public_html

# now run the syncer
su - backy -c "sh -c 'cd dropbox-syncer && ruby cron.rb'"