#!/bin/bash
set -eo pipefail
shopt -s nullglob

# if command starts with an option, prepend mysqld
if [ "${1:0:1}" = '-' ]; then
        set -- mysqld "$@"
fi

# skip setup if they want an option that stops mysqld
wantHelp=
for arg; do
        case "$arg" in
                -'?'|--help|--print-defaults|-V|--version)
                        wantHelp=1
                        break
                        ;;
        esac
done

# usage: file_env VAR [DEFAULT]
#    ie: file_env 'XYZ_DB_PASSWORD' 'example'
# (will allow for "$XYZ_DB_PASSWORD_FILE" to fill in the value of
#  "$XYZ_DB_PASSWORD" from a file, especially for Docker's secrets feature)
file_env() {
        local var="$1"
        local fileVar="${var}_FILE"
        local def="${2:-}"
        if [ "${!var:-}" ] && [ "${!fileVar:-}" ]; then
                echo >&2 "error: both $var and $fileVar are set (but are exclusive)"
                exit 1
        fi
        local val="$def"
        if [ "${!var:-}" ]; then
                val="${!var}"
        elif [ "${!fileVar:-}" ]; then
                val="$(< "${!fileVar}")"
        fi
        export "$var"="$val"
        unset "$fileVar"
}

_check_config() {
        toRun=( "$@" --verbose --help --log-bin-index="$(mktemp -u)" )
        if ! errors="$("${toRun[@]}" 2>&1 >/dev/null)"; then
                cat >&2	<<-EOM

				ERROR: mysqld failed while attempting to check config
				command was: "${toRun[*]}"

				$errors
				EOM
                exit 1
        fi
}

# Fetch value from server config
# We use mysqld --verbose --help instead of my_print_defaults because the
# latter only show values present in config files, and not server defaults
_get_config() {
        local conf="$1"; shift
        "$@" --verbose --help --log-bin-index="$(mktemp -u)" 2>/dev/null | awk '$1 == "'"$conf"'" { print $2; exit }'
}

# allow the container to be started with `--user`
if [ "$1" = 'mysqld' -a -z "$wantHelp" -a "$(id -u)" = '0' ]; then
        _check_config "$@"
        DATADIR="$(_get_config 'datadir' "$@")"
        mkdir -p "$DATADIR"
        find "$DATADIR" \! -user mysql -exec chown mysql '{}' +
        exec gosu mysql "$BASH_SOURCE" "$@"
fi

if [ "$1" = 'mysqld' -a -z "$wantHelp" ]; then
        # still need to check config, container may have started with --user
        _check_config "$@"
        # Get config
        DATADIR="$(_get_config 'datadir' "$@")"

        if [ ! -d "$DATADIR/mysql" ]; then
                file_env 'MYSQL_ROOT_PASSWORD'
                if [ -z "$MYSQL_ROOT_PASSWORD" -a -z "$MYSQL_ALLOW_EMPTY_PASSWORD" -a -z "$MYSQL_RANDOM_ROOT_PASSWORD" ]; then
                        echo >&2 'error: database is uninitialized and password option is not specified '
                        echo >&2 '  You need to specify one of MYSQL_ROOT_PASSWORD, MYSQL_ALLOW_EMPTY_PASSWORD and MYSQL_RANDOM_ROOT_PASSWORD'
                        exit 1
                fi

                mkdir -p "$DATADIR"

                echo 'Initializing database'
                # "Other options are passed to mysqld." (so we pass all "mysqld" arguments directly here)
                mysql_install_db --datadir="$DATADIR" --rpm "${@:2}"
                echo 'Database initialized'

                SOCKET="$(_get_config 'socket' "$@")"
                "$@" --skip-networking --socket="${SOCKET}" &
                pid="$!"

                mysql=( mysql --protocol=socket -uroot -hlocalhost --socket="${SOCKET}" )

                for i in {60..0}; do
                        if echo 'SELECT 1' | "${mysql[@]}" &> /dev/null; then
                                break
                        fi
                        echo 'MySQL init process in progress...'
                        sleep 1
                done
                if [ "$i" = 0 ]; then
                        echo >&2 'MySQL init process failed.'
                        exit 1
                fi

                if [ -z "$MYSQL_INITDB_SKIP_TZINFO" ]; then
                        # sed is for https://bugs.mysql.com/bug.php?id=20545
                        mysql_tzinfo_to_sql /usr/share/zoneinfo | sed 's/Local time zone must be set--see zic manual page/FCTY/' | "${mysql[@]}" mysql
                fi

                if [ ! -z "$MYSQL_RANDOM_ROOT_PASSWORD" ]; then
                        export MYSQL_ROOT_PASSWORD="$(pwgen -1 32)"
                        echo "GENERATED ROOT PASSWORD: $MYSQL_ROOT_PASSWORD"
                fi

                rootCreate=
                # default root to listen for connections from anywhere
                file_env 'MYSQL_ROOT_HOST' '%'
                if [ ! -z "$MYSQL_ROOT_HOST" -a "$MYSQL_ROOT_HOST" != 'localhost' ]; then
                        # no, we don't care if read finds a terminating character in this heredoc
                        # https://unix.stackexchange.com/questions/265149/why-is-set-o-errexit-breaking-this-read-heredoc-expression/265151#265151
                        read -r -d '' rootCreate	<<-EOSQL || true
						CREATE USER 'root'@'${MYSQL_ROOT_HOST}' IDENTIFIED BY '${MYSQL_ROOT_PASSWORD}' ;
						GRANT ALL ON *.* TO 'root'@'${MYSQL_ROOT_HOST}' WITH GRANT OPTION ;
						EOSQL
                fi

                "${mysql[@]}"	<<-EOSQL
						-- What's done in this file shouldn't be replicated
						--  or products like mysql-fabric won't work
						SET @@SESSION.SQL_LOG_BIN=0;

						DELETE FROM mysql.user WHERE user NOT IN ('mysql.sys', 'mysqlxsys', 'root') OR host NOT IN ('localhost') ;
						SET PASSWORD FOR 'root'@'localhost'=PASSWORD('${MYSQL_ROOT_PASSWORD}') ;
						GRANT ALL ON *.* TO 'root'@'localhost' WITH GRANT OPTION ;
						${rootCreate}
						DROP DATABASE IF EXISTS test ;
						FLUSH PRIVILEGES ;
					EOSQL

                if [ ! -z "$MYSQL_ROOT_PASSWORD" ]; then
                        mysql+=( -p"${MYSQL_ROOT_PASSWORD}" )
                fi

                file_env 'MYSQL_DATABASE'
                if [ "$MYSQL_DATABASE" ]; then
                        echo "CREATE DATABASE IF NOT EXISTS \`$MYSQL_DATABASE\` ;" | "${mysql[@]}"
                        mysql+=( "$MYSQL_DATABASE" )
                fi

                file_env 'MYSQL_USER'
                file_env 'MYSQL_PASSWORD'
                if [ "$MYSQL_USER" -a "$MYSQL_PASSWORD" ]; then
                        echo "CREATE USER '$MYSQL_USER'@'%' IDENTIFIED BY '$MYSQL_PASSWORD' ;" | "${mysql[@]}"

                        if [ "$MYSQL_DATABASE" ]; then
                                echo "GRANT ALL ON \`$MYSQL_DATABASE\`.* TO '$MYSQL_USER'@'%' ;" | "${mysql[@]}"
                        fi
                fi

                echo
                for f in /docker-entrypoint-initdb.d/*; do
                        case "$f" in
                                *.sh)     echo "$0: running $f"; . "$f" ;;
                                *.sql)    echo "$0: running $f"; "${mysql[@]}" < "$f"; echo ;;
                                *.sql.gz) echo "$0: running $f"; gunzip -c "$f" | "${mysql[@]}"; echo ;;
                                *)        echo "$0: ignoring $f" ;;
                        esac
                        echo
                done

                if ! kill -s TERM "$pid" || ! wait "$pid"; then
                        echo >&2 'MySQL init process failed.'
                        exit 1
                fi

                echo
                echo 'MySQL init process done. Ready for start up.'
                echo
        fi
fi

exec "$@"