#!/bin/bash

###########################
####### LOAD CONFIG #######
###########################

while [ $# -gt 0 ]; do
  case $1 in
    -c)
      if [ -r "$2" ]; then
        source "$2"
        shift 2
      else
        ${ECHO} "Unreadable config file \"$2\"" 1>&2
        exit 1
      fi
      ;;
    *)
      ${ECHO} "Unknown Option \"$1\"" 1>&2
      exit 2
      ;;
  esac
done

if [ $# = 0 ]; then
  if [ -f "/opt/xsg/etc/my_backup.config" ]; then
    source "/opt/xsg/etc/my_backup.config"
  fi
fi;

###########################
#### PRE-BACKUP CHECKS ####
###########################
# Make sure we're running as the required backup user
if [ "$BACKUP_USER" != "" -a "$(id -un)" != "$BACKUP_USER" ]; then
	echo "This script must be run as $BACKUP_USER. Exiting." 1>&2
	exit 1;
fi;

###########################
### INITIALISE DEFAULTS ###
###########################
if [ ! $HOSTNAME ]; then
	HOSTNAME="localhost"
fi;

if [ ! $USERNAME ]; then
	USERNAME="root"
fi;

###########################
#### START THE BACKUPS ####
###########################
FINAL_BACKUP_DIR=$BACKUP_DIR"`date +\%Y-\%m-\%d`/"

echo "Making backup directory in $FINAL_BACKUP_DIR"

if ! mkdir -p $FINAL_BACKUP_DIR; then
	echo "Cannot create backup directory in $FINAL_BACKUP_DIR. Go and fix it!" 1>&2
	exit 1;
fi;

#######################
### GLOBALS BACKUPS ###
#######################
echo -e "\n\nPerforming dump backup"
echo -e "--------------------------------------------\n"

if [ $ENABLE_DUMP_BACKUPS = "yes" ]
then
  echo "Dump backup"

  #if ! sudo -H pg_dumpall -g -h "$HOSTNAME" -U "$USERNAME" | gzip > $FINAL_BACKUP_DIR"globals".sql.gz.in_progress; then
  #  echo "[!!ERROR!!] Failed to produce globals backup" 1>&2
  #else
  #  mv $FINAL_BACKUP_DIR"globals".sql.gz.in_progress $FINAL_BACKUP_DIR"globals".sql.gz
  #fi
else
	echo "None"
fi

###########################
### SCHEMA-ONLY BACKUPS ###
###########################
for SCHEMA_ONLY_DB in ${SCHEMA_ONLY_LIST//,/ }
do
	SCHEMA_ONLY_CLAUSE="$SCHEMA_ONLY_CLAUSE or datname ~ '$SCHEMA_ONLY_DB'"
done

SCHEMA_ONLY_QUERY="select datname from pg_database where false $SCHEMA_ONLY_CLAUSE order by datname;"

echo -e "\n\nPerforming schema-only backups"
echo -e "--------------------------------------------\n"

SCHEMA_ONLY_DB_LIST=`sudo -H psql -h "$HOSTNAME" -U "$USERNAME" -At -c "$SCHEMA_ONLY_QUERY" postgres`

echo -e "The following databases were matched for schema-only backup:\n${SCHEMA_ONLY_DB_LIST}\n"

for DATABASE in $SCHEMA_ONLY_DB_LIST
do
	echo "Schema-only backup of $DATABASE"

	if ! sudo -H pg_dump -Fp -s -h "$HOSTNAME" -U "$USERNAME" "$DATABASE" | gzip > $FINAL_BACKUP_DIR"$DATABASE"_SCHEMA.sql.gz.in_progress; then
		echo "[!!ERROR!!] Failed to backup database schema of $DATABASE" 1>&2
	else
		mv $FINAL_BACKUP_DIR"$DATABASE"_SCHEMA.sql.gz.in_progress $FINAL_BACKUP_DIR"$DATABASE"_SCHEMA.sql.gz
	fi
done

###########################
###### FULL BACKUPS #######
###########################
for SCHEMA_ONLY_DB in ${SCHEMA_ONLY_LIST//,/ }
do
	EXCLUDE_SCHEMA_ONLY_CLAUSE="$EXCLUDE_SCHEMA_ONLY_CLAUSE and datname !~ '$SCHEMA_ONLY_DB'"
done

FULL_BACKUP_QUERY="select datname from pg_database where not datistemplate and datallowconn $EXCLUDE_SCHEMA_ONLY_CLAUSE order by datname;"

echo -e "\n\nPerforming full backups"
echo -e "--------------------------------------------\n"

for DATABASE in `sudo -H psql -h "$HOSTNAME" -U "$USERNAME" -At -c "$FULL_BACKUP_QUERY" postgres`
do
	if [ $ENABLE_PLAIN_BACKUPS = "yes" ]
	then
		echo "Plain backup of $DATABASE"

		if ! sudo -H pg_dump -Fp -h "$HOSTNAME" -U "$USERNAME" "$DATABASE" | gzip > $FINAL_BACKUP_DIR"$DATABASE".sql.gz.in_progress; then
			echo "[!!ERROR!!] Failed to produce plain backup database $DATABASE" 1>&2
		else
			mv $FINAL_BACKUP_DIR"$DATABASE".sql.gz.in_progress $FINAL_BACKUP_DIR"$DATABASE".sql.gz
		fi
	fi

	if [ $ENABLE_CUSTOM_BACKUPS = "yes" ]
	then
		echo "Custom backup of $DATABASE"

		if ! sudo -H pg_dump -Fc -h "$HOSTNAME" -U "$USERNAME" "$DATABASE" -f $FINAL_BACKUP_DIR"$DATABASE".custom.in_progress; then
			echo "[!!ERROR!!] Failed to produce custom backup database $DATABASE" 1>&2
		else
			mv $FINAL_BACKUP_DIR"$DATABASE".custom.in_progress $FINAL_BACKUP_DIR"$DATABASE".custom
		fi
	fi

done

echo -e "\nAll database backups complete!"
