#!/bin/sh

mw_var()
{
        local mw_local_settings=$1
        local mw_var=$2

        sed -n "s/^\$$mw_var = \"\(.*\)\";/\1/p" $mw_local_settings
}

mw_backup()
{
        local mw_root=$1
        local mw_name=$(basename $mw_root)
        local mw_local_settings=$mw_root/LocalSettings.php
        local mw_local_settings_backup=$(tempfile)
        local mw_db_type=$(mw_var $mw_local_settings "wgDBtype")
        local mw_db_server=$(mw_var $mw_local_settings "wgDBserver")
        local mw_db_name=$(mw_var $mw_local_settings "wgDBname")
        local mw_db_user=$(mw_var $mw_local_settings "wgDBuser")
        local mw_db_password=$(mw_var $mw_local_settings "wgDBpassword")
        local mw_backup_output="/opt/mediawiki-backup/$mw_name"

        [ "$mw_db_type" != "mysql" ] && echo "$mw_db_type is not supported" && exit 1
        [ ! -d "$mw_backup_output" ] && echo "$mw_backup_output directory does not exist" && exit 2
        [ ! -d "$mw_backup_output/.git" ] && echo "$mw_backup_output directory is not a git repository" && exit 3

        cp -p $mw_local_settings $mw_local_settings_backup
        cp $mw_local_settings $mw_backup_output
        echo "\$wgReadOnly = 'Dumping Database, Access will be restored shortly';" >> $mw_local_settings

        mysqldump -h $mw_db_server -u $mw_db_user -p $mw_db_name --default-character-set=utf8 > $mw_backup_output/mw-db.sql

        cd $mw_backup_output
        local mw_commit_message="$(date --iso-8601) - $(tail -n 1 mw-db.sql)"
        sed -i '$ d' mw-db.sql
        git add mw-db.sql LocalSettings.php && git commit -m "$mw_commit_message"
        cd -

        mv $mw_local_settings_backup $mw_local_settings
}