#!/bin/bash
# back up a MySQL database
# $Id$

OIFS="$IFS"
IFS=" 	
"

if test -f "$HOME/bin/functions"
then
    . "$HOME/bin/functions"
else
    echo "Cannot open functions library $HOME/bin/functions" 1>&2
    exit 1
fi

abort()
{
	notice "Aborted"
}

cleanup()
{
    info "Cleaning up"

    if test -f "$dfout"
    then
        run rm -rf -- "$dfout"
    fi
}

#
# default configuration
#
debug=
quiet=true
src=/home/mikelward/library
tmpdir="${TMPDIR:-$HOME/tmp}"
dst=home:/home/mikel/library
logfile="$HOME"/log/librarybackup.log
dateformat='%-e %B %Y'
timeformat='%H:%M:%S'
#databases="books movies music"
databases="library"

#
# start
#
trap 'abort' INT TERM
trap 'cleanup' EXIT

src=${src%/}

info "Starting backup of $src on "$(date +"$dateformat")" at "$(date +"$timeformat")

if test ! -d "$src"
then
	mkdir "$src"
fi

#
# ensure required programs are available
#
if ! silent type mysqldump
then
    error "Cannot find mysqldump in PATH"
    exit 1
fi

#
# create a dump of the desired MySQL databases
#
set -- $databases
if test $# -ge 1
then
	for database in $databases
	do
		info "Dumping $database"
		mysqldump $database > $src/$database.sql
		if test $? -eq 0
		then
			debug "OK"
		else
			error "Error dumping $database"
		fi
	done
else
	info "Dumping all databases"
	mysqldump --all-databases > $src/library.sql
	if test $? -eq 0
	then 
		debug "OK"
	else
		error "Error dumping databases"
	fi
fi

#
# check disk space requirements
#
size=$(get_size_of_file_or_directory "$src")
if test $? -ne 0
then
    error "Cannot determine disk usage of $src"
    exit 1
fi

tmpdir=$(get_temporary_directory)
if test $? -ne 0
then
    error "Cannot determine temporary directory"
    exit 1
fi

available=$(get_free_space_on_filesystem "$tmpdir")
if test $? -ne 0
then
    error "Cannot determine free space on $tmpdir"
    exit 1
fi

if test $available -lt $size
then
    error "Need at least $size kilobytes free on $tmpdir"
    exit 1
fi

#
# copy the hot copy to the backup directory
#
if is_remote "$dst"
then
    debug "Remote destination"

    info "Synchronizing $src to $dst"
    flags=
    if test "$debug"
    then
        flags="$flags -v"
    fi
    if test "$quiet"
    then
        flags="$flags -q"
    fi
    #scp -C -r $flags "$src" "$dst"
    # ensure source has a trailing slash so we only copy the directory contents
    # (local:~/svn.12345/ -> remote:~/svn rather than
    #  local:~/svn.12345/ -> remote:~/svn/svn.12345)
    run rsync -a --delete $flags "$src"/ "$dst"
    if test $? -ne 0
    then
        error "Error synchronizing $src to $dst"
        exit 1
    fi
else
    debug "Local destination, using cp"
    error "Local files are currently unsupported"
    exit 1
fi

info "Finished backup of $src on "$(date +"$dateformat")" at "$(date +"$timeformat")