#!/bin/bash

# /usr/local/sbin/vm-firstrun.sh

# This script depends on having these packages installed:
#   - cloud-utils-growpart
#   - parted

# This should be a simple bash file that sets the CFG_* variables
[ -f /etc/sysconfig/vm-firstrun ] && . /etc/sysconfig/vm-firstrun

## Set default values for anything that wasn't already set
# This will be run at firstboot to generate the hostname
CFG_HOSTNAME_SCRIPT="${CFG_HOSTNAME_SCRIPT:=uuidgen}"
# These can be set in config, there's just no reason for a default besides (blank)
# CFG_HOSTNAME_PREFIX="${CFG_HOSTNAME_PREFIX:=}"
# CFG_HOSTNAME_POSTFIX="${CFG_HOSTNAME_POSTFIX:=}"
CFG_DOMAIN="${CFG_DOMAIN:=localdomain}"
CFG_ROOTFS_DISK="${CFG_ROOTFS_DISK:=/dev/vda}"
CFG_DISK_TYPE="${CFG_DISK_TYPE:=lvm}"
CFG_ROOTFS_PARTITION="${CFG_ROOTFS_PARTITION:=3}"
CFG_ROOTFS_TYPE="${CFG_ROOTFS_TYPE:=xfs}"
CFG_SERVICE_NAME="${CFG_SERVICE_NAME:=vm-firstrun}"

## Helper Functions
function log() {
    echo "$@" | logger --stderr -t vm-firstrun
}


## Do the things
old_hostname="$(hostname -f)"
new_hostname="${CFG_HOSTNAME_PREFIX}$(${CFG_HOSTNAME_SCRIPT})${CFG_HOSTNAME_POSTFIX}"
if ! [ -z "${CFG_DOMAIN}" ]; then
    new_hostname="${new_hostname}.${CFG_DOMAIN}"
fi

log "Setting hostname from '${old_hostname}' to '${new_hostname}'"
hostnamectl set-hostname "${new_hostname}"

if [ -b "${CFG_ROOTFS_DISK}" ]; then
    if [ -b "${CFG_ROOTFS_DISK}${CFG_ROOTFS_PARTITION}" ]; then

        # # expand the partition
        # log "Expanding rootfs partition"
        # growpart "${CFG_ROOTFS_DISK}" "${CFG_ROOTFS_PARTITION}"
        # # reload partition table
        # log "Reloading partition table"
        # partprobe "${CFG_ROOTFS_DISK}"
        # expand the partition
        log "Expanding rootfs partition"
        growpart "${CFG_ROOTFS_DISK}" "${CFG_ROOTFS_PARTITION}"
        pvresize "${CFG_ROOTFS_DISK}""${CFG_ROOTFS_PARTITION}"
        lvextend -l +100%FREE /dev/mapper/centos-root
        # # reload partition table
        log "Reloading partition table"
        partprobe "${CFG_ROOTFS_DISK}"

        # grow the rootfs
        case "${CFG_ROOTFS_TYPE}" in
            xfs)
                log "Growing rootfs of type: ${CFG_ROOTFS_TYPE}"
                xfs_growfs /
                ;;
            ext*)
                log "Growing ${CFG_ROOTFS_TYPE} rootfs on device: ${CFG_ROOTFS_DISK}${CFG_ROOTFS_PARTITION}"
                resize2fs "${CFG_ROOTFS_DISK}${CFG_ROOTFS_PARTITION}"
                ;;
            *)
                log "Unsupported rootfs type: ${CFG_ROOTFS_TYPE}"
                log "Doing nothing, please grow the fs manually"
                ;;
        esac
    else
        log "rootfs partition not found, unable to expand: ${CFG_ROOTFS_DISK}${CFG_ROOTFS_PARTITION}"
    fi
else
    log "rootfs disk not found, unable to expand: ${CFG_ROOTFS_DISK}"
fi

#Run update to get the latest packages
log "Updating latest packages"
yum update -y
log "updating done"

log "initial config done, disabling myself"
systemctl disable "${CFG_SERVICE_NAME}"