###
### common bindings for dbconfig-common
###
###	all variables and functions fall under the namespace "dbc_foo" and
###	"_dbc_foo", depending on whether or not they are "external"
###

[ "$_dbc_logfile" ] || _dbc_logfile="/var/log/dbconfig-common/dbc.log"

##
## dbc_logpart: log interal messages (without newline)
##
dbc_logpart(){
	printf "$* " >&2
	printf "$* " >> $_dbc_logfile
}

##
## dbc_logline: log interal messages
##
dbc_logline(){
	printf "$*.\n" >&2
	printf "$*.\n" >> $_dbc_logfile
}

###
### simple debugging function
###
_dbc_debug(){
	if [ "${dbc_debug:-}" ]; then
		dbc_logline "$@"
	fi
}

##
## internal check for an installed db client package
##
_dbc_detect_installed_dbtype(){
	_dbc_debug "_dbc_detect_installed_dbtype() $@"
	# see if the dbtype is already installed.  this is still not 100% accurate
	case "$1" in
	mysql)
		if ! which mysql >/dev/null; then
			return 1
		fi
	;;
	pgsql|psql)
		# if postgresql-client-common is installed without postgresql-client-8.x,
		# psql --version will exit with an error
		if ! which psql >/dev/null 2>&1 || \
		   ! psql --version >/dev/null 2>&1; then
			return 1
		fi
	;;
	"sqlite"|"sqlite3")
		if ! which $1 >/dev/null 2>&1; then
			return 1
		fi
	;;
	*)
		dbc_logline "_dbc_detect_installed_dbtype() called for unknown dbtype $@"
		return 1
	;;
	esac
	return 0
}

##
## internal sanity check for certain important variables
##
_dbc_sanity_check(){
	while [ $# -ne 0 ]; do
		case "$1" in
		"package")
			if [ -z "$dbc_package" ]; then
				dbc_error="dbconfig-common can not determine the
					name of the package it is configuring."
				dbc_logline "sanity check failed for dbc_package"
				return 1
			fi
		;;
		"packageconfig")
			if [ -z "$dbc_packageconfig" ]; then
				dbc_error="dbconfig-common can not determine the
					name of the package configuration file."
				dbc_logline "sanity check failed for dbc_packageconfig"
				return 1
			fi
		;;
		"dbtype")
			if [ -z "$dbc_dbtype" ]; then
				dbc_error="dbconfig-common can not determine the
					database type."
				dbc_logline "sanity check failed for dbc_dbtype"
				return 1
			fi
		;;
		"command")
			if [ -z "$dbc_command" ]; then
				dbc_error="dbconfig-common can not determine the
					maintainer script running it."
				dbc_logline "sanity check failed for dbc_command"
				return 1
			fi
		;;
		"dbname")
			if [ -z "$dbc_dbname" ]; then
				dbc_error="No database name specified. Have
				       to know the name to create it."
				dbc_logline "sanity check failed for dbc_dbname"
				return 1
			fi
		;;
		"dbadmin")
			if [ -z "$dbc_dbadmin" ]; then
				dbc_error="No database administrator specified."
				dbc_logline "sanity check failed for dbc_dbadmin"
				return 1
			fi
		;;
		"dbuser")
			if [ -z "$dbc_dbuser" ]; then
				dbc_error="No database user specified."
				dbc_logline "sanity check failed for dbc_dbuser"
				return 1
				fi
				;;
		"dbpass")
			if [ -z "$dbc_dbpass" ]; then
				dbc_error="No database password specified."
				dbc_logline "sanity check failed for dbc_dbpass"
				return 1
				fi
				;;
		"mysql"|"psql"|"sqlite"|"sqlite3")
			if ! _dbc_detect_installed_dbtype $1; then
				dbc_error="No $1 client to execute.  (have
				       you installed the ${dbc_dbclientpackage:-$1} package?)"
				dbc_logline "sanity check failed for $1"
				return 1
			fi
		;;
		"createdb")
			if ! which createdb >/dev/null; then
				dbc_error="No pgsql createdb to execute.  (have
				       you installed postgresql-client?"
				dbc_logline "sanity check failed for createdb"
				return 1
			fi
		;;
		"dropdb")
			if ! which dropdb >/dev/null; then
				dbc_error="No pgsql dropdb to execute.  (have
				       you installed postgresql-client?"
				dbc_logline "sanity check failed for dropdb"
				return 1
			fi
		;;
		"createuser")
			if ! which createuser >/dev/null; then
				dbc_error="No pgsql createuser to execute.  (have
				       you installed postgresql-client?"
				dbc_logline "sanity check failed for createuser"
				return 1
			fi
		;;
		"dropuser")
			if ! which dropuser >/dev/null; then
				dbc_error="No pgsql dropuser to execute.  (have
				       you installed postgresql-client?"
				dbc_logline "sanity check failed for dropuser"
				return 1
			fi
		;;
		"pg_dump")
			if ! which pg_dump >/dev/null; then
				dbc_error="No pgsql pg_dump to execute.  (have
				       you installed postgresql-client?"
				dbc_logline "sanity check failed for pg_dump"
				return 1
			fi
		;;
		"mysqldump")
			if ! which mysqldump >/dev/null; then
				dbc_error="No mysqldump to execute.  (have
				       you installed mysql-client?"
				dbc_logline "sanity check failed for mysqldump"
				return 1
			fi
		;;
		*)
			dbc_error="don't know how to sanity check for $1"
			dbc_logline "don't know how to sanity check for $1"
			return 1
		;;
		esac
		shift
	done
}

dbc_mktemp(){
	local tfile ttemplate
	if [ "${1:-}" ]; then 
		ttemplate="$1"; 
	else
		ttemplate="dbconfig-common.XXXXXX"; 
	fi

	tfile=`mktemp -t "$ttemplate"`
	if [ ! -f "$tfile" ]; then
		dbc_error="error creating temporary file"
		dbc_logline "error creating temporary file"
		return 1
	else
		echo $tfile
	fi
}