#!/usr/bin/env bash

which sudo &>/dev/null && SUDO="sudo" || SUDO=""

debrelease="buster"
debmirror="http://debian.mirror.rafal.ca/debian"
debpkglist="lvm2,parted,gdisk,grub-pg,linux-image-amd64,sudo,vim,gpg,gpg-agent,aptitude,openssh-server"

clear

titlestring_text="| Preparing to install a PVC node base system. |"
titlestring_len="$( wc -c <<<"${titlestring_text}" )"
for i in $( seq 2 ${titlestring_len} ); do echo -n "-"; done; echo
echo "${titlestring_text}"
for i in $( seq 2 ${titlestring_len} ); do echo -n "-"; done; echo
echo

echo "1) Please enter a fully-qualified hostname for the system."
while [[ -z ${target_hostname} ]]; do
    echo
    echo -n "> "
    read target_hostname
    if [[ -z ${target_hostname} ]]; then
        echo
        echo "Please enter a hostname."
        continue
    fi
    echo
done

disks="$(
    for disk in /dev/sd?; do
        gdisk_data="$( $SUDO gdisk -l ${disk} )"
        echo -n "${disk}"
        echo -n "\t$( grep "^Model:" <<<"${gdisk_data}" | awk '{ $1=""; print $0 }' )"
        echo -n "\t$( grep "^Disk ${disk}:" <<<"${gdisk_data}" | awk '{ $1=$2=""; print $0 }' )"
        echo
    done
)"

echo "2) Please enter the disk to install the PVC base system to. This disk will be"
echo "wiped, an LVM PV created on it, and the system installed to this LVM."
echo
echo "Available disks:"
echo
echo -e "$( sed 's/\(.*\)/  \1/' <<<"${disks[@]}" )"
while [[ ! -b ${target_disk} ]]; do
    echo
    echo -n "> "
    read target_disk
    if [[ ! -b ${target_disk} ]]; then
        echo
        echo "Please enter a valid target disk."
        continue
    fi
    echo
done

for interface in $( ip address | grep '^[0-9]' | grep 'enp\|ens\|wlp' | awk '{ print $2 }' | tr -d ':' ); do
    $SUDO ip link set ${interface} up
done
sleep 2
interfaces="$(
    ip address | grep '^[0-9]' | grep 'enp\|ens\|wlp' | awk '{ print $2"\t"$3 }' | tr -d ':'
)"
echo "3a) Please enter the primary network interface for external connectivity."
echo
echo "Available interfaces:"
echo
echo -e "$( sed 's/\(.*\)/  \1/' <<<"${interfaces[@]}" )"
while [[ -z ${target_interface} ]]; do
    echo
    echo -n "> "
    read target_interface
    if ! grep -qw "${target_interface}" <<<"${interfaces[@]}"; then
        echo
        echo "Please enter a valid interface."
        target_interface=""
        continue
    fi
    echo
done

echo "3b) Please enter the IP address, in CIDR format [X.X.X.X/YY], of the primary network interface."
echo "Leave blank for DHCP configuration of the interface on boot."
echo
echo -n "> "
read target_ipaddr
if [[ -n ${target_ipaddr} ]]; then
    target_netformat="static"
    echo
    echo "3c) Please enter the default gateway IP address of the primary"
    echo "network interface."
    while [[ -z ${target_defgw} ]]; do
        echo
        echo -n "> "
        read target_defgw
        if [[ -z ${target_defgw} ]]; then
            echo
            echo "Please enter a default gateway; the installer requires Internet access."
            continue
        fi
        echo
    done
else
    target_netformat="dhcp"
    echo
fi

echo "4) Please enter an HTTP URL containing a text list of SSH authorized keys to"
echo "fetch. These keys will be allowed access to the 'deploy' user via SSH."
echo "Leave blank to bypass this and use a password instead."
echo
echo -n "> "
read target_keys_url
if [[ -z ${target_keys_url} ]]; then
    echo
    echo "No SSH keys URL specified. Falling back to password configuration."
    echo
    echo "5) Please enter a password (hidden), twice, for the 'deploy' user."
    while [[ -z "${target_password}" ]]; do
        echo
        echo -n "> "
        read -s target_password_1
        echo
        echo -n "> "
        read -s target_password_2
        echo
        if [[ -n "${target_password_1}" && "${target_password_1}" -eq "${target_password_2}" ]]; then
            target_password="${target_password_1}"
        else
            echo
            echo "The specified passwords do not match or are empty."
        fi
    done
fi
echo

titlestring_text="| Proceeding with installation of host '${target_hostname}' to disk '${target_disk}'. |"
titlestring_len="$( wc -c <<<"${titlestring_text}" )"
for i in $( seq 2 ${titlestring_len} ); do echo -n "-"; done; echo
echo "${titlestring_text}"
for i in $( seq 2 ${titlestring_len} ); do echo -n "-"; done; echo
echo

### Script begins ###
set -o errexit

echo -n "Bringing up primary network interface in ${target_netformat} mode... "
case mode in ${target_netformat}
    'static')
        $SUDO ip link set ${target_interface} up &>/dev/null
        $SUDO ip address add ${target_ipaddr} dev ${target_interface} &>/dev/null
        $SUDO ip route add default via ${target_defgw} &>/dev/null
        formatted_ipaddr="$( sipcalc ${target_ipaddr} | grep -v '(' | awk '/Host address/{ print $NF }' )"
        formatted_netmask="$( sipcalc ${target_ipaddr} | grep -v '(' | awk '/Network mask/{ print $NF }' )"
        target_interfaces_block="auto ${target_interface}\niface ${target_interface} inet ${target_netformat}\n\taddress ${formatted_ipaddr}\n\tnetmask ${formatted_netmask}\n\tgateway ${target_defgw}"
    ;;
    'dhcp')
        $SUDO dhclient ${target_interface} &>/dev/null
        target_interfaces_block="auto ${target_interface}\niface ${target_interface} inet ${target_netformat}"
    ;;
esac
echo "done."

echo -n "Preparing block device... "
# New GPT, part 1 64MB ESP, part 2 960MB BOOT, part 3 inf LVM PV
echo -e "o\ny\nn\n1\n\n64M\nEF00\nn\n2\n\n960M\n8300\nn\n3\n\n\n8E00\nw\ny\n" | $SUDO gdisk ${target_disk}
echo "done."

echo -n "Rescanning disks... "
$SUDO partprobe &>/dev/null
echo "done."

echo -n "Creating LVM PV... "
$SUDO pvcreate ${target_disk}3 &>/dev/null
echo "done."

echo -n "Creating LVM VG named 'vgx'... "
$SUDO vgcreate vgx ${target_disk}3 &>/dev/null
echo "done."

echo -n "Creating root logical volume (16GB, ext4)... "
$SUDO lvcreate -L 16G -n root vgx &>/dev/null
$SUDO mkfs.ext4 -f /dev/vgx/root &>/dev/null
echo "done."

echo -n "Creating ceph logical volume (16GB, ext4)... "
$SUDO lvcreate -L 16G -n ceph vgx &>/dev/null
$SUDO mkfs.ext4 -f /dev/vgx/ceph &>/dev/null
echo "done."

echo -n "Creating swap logical volume (8GB)... "
$SUDO lvcreate -L 8G -n swap vgx &>/dev/null
$SUDO mkswap -f /dev/vgx/swap &>/dev/null
echo "done."

echo -n "Mounting disks on temporary target... "
target=$( mktemp -d )
$SUDO mount /dev/vgx/root ${target} &>/dev/null
$SUDO mkdir -p ${target}/boot &>/dev/null
$SUDO mount ${target_disk}2 ${target}/boot &>/dev/null
$SUDO mkdir -p ${target}/boot/efi &>/dev/null
$SUDO mount ${target_disk}1 ${target}/boot/efi &>/dev/null
$SUDO mkdir -p ${target}/var/lib/ceph &>/dev/null
$SUDO mount /dev/vgx/ceph ${target}/var/lib/ceph &>/dev/null
echo "done."

echo -n "Running debootstrap install... "
$SUDO debootstrap --include=${debpkglist} ${debrelease} ${target}/ ${debmirror} &>/dev/null
echo "done."

# Determine the bypath name of the specified system disk
for disk in /dev/disk/by-path/*; do
    bypathlink="$( readlink ${disk} | awk -F'/' '{ print $NF }' )"
    enteredname="$( awk -F'/' '{ print $NF }' <<<"${target_disk}" )"
    if [[ ${bypathlink} == ${enteredname} ]]; then
        bypath_disk="${disk}"
    fi
done

echo -n "Adding fstab entries... "
echo "/dev/mapper/vgx-root / ext4 errors=remount-ro 0 1" | $SUDO tee -a ${target}/etc/fstab &>/dev/null
echo "/dev/mapper/vgx-ceph /var/lib/ceph ext4 errors=remount-ro 0 2" | $SUDO tee -a ${target}/etc/fstab &>/dev/null
echo "/dev/mapper/vgx-swap nonde swap sw 0 0" | $SUDO tee -a ${target}/etc/fstab &>/dev/null
echo "${bypath_disk}2 /boot ext2 defaults 0 2" | $SUDO tee -a ${target}/etc/fstab &>/dev/null
echo "${bypath_disk}1 /boot/efi vfat umask=0077 0 2" | $SUDO tee -a ${target}/etc/fstab &>/dev/null
echo "done."

echo -n "Adding interface segment... "
echo -e "${target_interfaces_block}" | $SUDO tee -a ${target}/etc/network/interfaces &>/dev/null
echo "done."

echo -n "Adding 'deploy' user... "
$SUDO mv ${target}/home ${target}/var/home &>/dev/null
$SUDO chroot ${target} useradd -u 200 -d /var/home/deploy -m -s /bin/bash -g operator -G sudo deploy &>/dev/null
$SUDO chroot ${target} mkdir -p /var/home/deploy/.ssh
if [[ -n ${target_keys_url} ]]; then
$SUDO wget -O ${target}/var/home/deploy/.ssh/authorized_keys ${target_keys_url}
else
echo "${target_password}" | $SUDO chroot ${target} passwd --stdin deploy &>/dev/null
fi

echo -n "Setting hostname... "
echo "${target_hostname}" | sudo tee ${target}/etc/hostname &>/dev/null
echo "done."

echo -n "Installing GRUB bootloader... "
$SUDO mount --bind /dev ${target}/dev &>/dev/null
$SUDO mount --bind /dev/pts ${target}/dev/pts &>/dev/null
$SUDO mount --bind /proc ${target}/proc &>/dev/null
$SUDO mount --bind /sys ${target}/sys &>/dev/null
$SUDO chroot ${target} grub-install --target=x86_64-efi ${target_disk} &>/dev/null
$SUDO chroot ${target} update-grub &>/dev/null
echo "done."

echo -n "Cleaning up... "
$SUDO umount ${target}/sys &>/dev/null
$SUDO umount ${target}/proc &>/dev/null
$SUDO umount ${target}/dev/pts &>/dev/null
$SUDO umount ${target}/dev &>/dev/null
$SUDO umount ${target}/var/lib/ceph &>/dev/null
$SUDO umount ${target}/boot/efi &>/dev/null
$SUDO umount ${target}/boot &>/dev/null
$SUDO umount ${target} &>/dev/null
echo "done."
echo

titlestring_text="| PVC node installation finished. Press <Enter> to reboot into the installed system. |"
titlestring_len="$( wc -c <<<"${titlestring_text}" )"
for i in $( seq 2 ${titlestring_len} ); do echo -n "-"; done; echo
echo "${titlestring_text}"
echo "Verify the system is configured as you would expect, add any additional interfaces"
echo "to the /etc/network/interfaces file, and then run the PVC Ansible role in"
echo "'bootstrap=yes' mode to continue deploying the PVC system."
for i in $( seq 2 ${titlestring_len} ); do echo -n "-"; done; echo
echo
read

$SUDO reboot