#!/bin/bash

#########################################################################
# Title: XenOrchestraInstallerUpdater                                   #
# Author: Roni Väyrynen                                                 #
# Repository: https://github.com/ronivay/XenOrchestraInstallerUpdater   #
#########################################################################

# image url is static and not configurable by user
IMAGE_URL="https://xo-image.yawn.fi/downloads/image.xva.gz"

function OSCheck {
    set -e

    if [[ -z $(command -v xe 2>/dev/null) ]]; then
        echo "this scripts needs xe command. make sure you're on xenserver/xcp-ng host"
        exit 1
    fi

    echo
    echo "Welcome. This script will import a preconfigured Debian 11 VM image which has Xen Orchestra installed using https://github.com/ronivay/XenOrchestraInstallerUpdater"
    echo "You need at least 2vCPU/4GB/10GB disk free resources to import VM"
    echo
    echo "Please report any issues to this github project"
    echo

}

function NetworkChoose {

    set +e

    # get network name/uuid of all available networks configured in the pool
    # shellcheck disable=SC1117
    IFS=$'\n' read -r -d '' -a networks <<<"$(xe network-list | grep "uuid\|name-label" | cut -d':' -f2 | sed 's/^ //' | paste - -)"

    echo
    echo "Which network should the VM use?"
    echo
    local PS3="Pick a number. CTRL+C to exit: "
    select network in "${networks[@]}"; do
        # get only the network uuid from array which we need later on when adding vif
        read -r -a network_split <<<"$network"
        networkuuid=${network_split[0]}

        # print a menu where to choose network from
        case $network in
            *)
                # save network uuid for later
                vifuuid="$networkuuid"
                break
                ;;
        esac
    done

}

function StorageChoose {

    set +e

    # get storage name/uuid of all available storages with content-type=user which should match all usable storage repositories
    # shellcheck disable=SC1117
    IFS=$'\n' read -r -d '' -a storages <<<"$(xe sr-list content-type=user | grep "uuid\|name-description" | cut -d':' -f2 | sed 's/^ //' | paste - -)"

    # bail out if no storage repositories are found
    if [[ ${#storages[@]} -eq 0 ]]; then
        echo "No storage repositories found, can't import VM"
        echo "Create SR and try again. More information: https://xcp-ng.org/docs/storage.html"
        exit 1
    fi

    echo "Which storage repository should the VM use?"
    echo "default will attempt to use pool default SR"
    echo
    local PS3="Pick a number. CTRL+C to exit: "
    select storage in "${storages[@]}" "default"; do
        # get only the storage repository uuid which we need later on when importing image
        read -r -a storage_split <<<"$storage"
        storageuuid=${storage_split[0]}

        # print a menu where to choose storage from
        case $storage in
            default)
                # this value is handled during import if set to default
                sruuid=default
                break
                ;;
            *)
                # save storage uuid for later
                sruuid=$storageuuid
                break
                ;;
        esac
    done

}

function NetworkSettings {

    set -e

    ipregex="^[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}$"

    echo
    echo "Set network settings for VM. Leave IP-address as blank to use DHCP"
    echo

    # read ip address from user input. dhcp is default if left empty
    read -r -p "IP address: " ipaddress
    ipaddress=${ipaddress:-dhcp}

    # if not using dhcp, we need more information
    if [[ "$ipaddress" != "dhcp" ]]; then
        # get network details from user and prompt again if input doesn't match ip address regex
        while ! [[ $ipaddress =~ $ipregex ]]; do
            echo "Check IP address format"
            read -r -p "IP address: " ipaddress
        done
        read -r -p "Netmask [255.255.255.0]: " netmask
        netmask=${netmask:-255.255.255.0}
        while ! [[ $netmask =~ $ipregex ]]; do
            echo "Check gateway format"
            read -r -p "Netmask [255.255.255.0]: " netmask
            netmask=${netmask:-255.255.255.0}
        done
        read -r -p "Gateway: " gateway
        while ! [[ $gateway =~ $ipregex ]] && [[ $gateway != "" ]]; do
            echo "Check gateway format"
            read -r -p "Gateway: " gateway
        done
        read -r -p "DNS [8.8.8.8]: " dns
        dns=${dns:-8.8.8.8}
        while ! [[ $dns =~ $ipregex ]]; do
            echo "Check dns format"
            read -r -p "DNS [8.8.8.8]: " dns
            dns=${dns:-8.8.8.8}
        done

    fi

}

function VMImport {

    set -e

    echo
    echo "Downloading and importing XVA image..."
    echo

    # Import image. We pipe through zcat because xe vm-import should transparently decompress gzipped image, but doesn't seem to understand when stream ends when piped through curl/wget whatnot.
    # if SR was not defined, we leave that parameter out
    if [[ $sruuid == "default" ]]; then
        uuid=$(curl "$IMAGE_URL" | zcat | xe vm-import filename=/dev/stdin)
    else
        uuid=$(curl "$IMAGE_URL" | zcat | xe vm-import filename=/dev/stdin sr-uuid="$sruuid")
    fi

    # exit if import failed for any reason
    # shellcheck disable=SC2181
    if [[ $? != "0" ]]; then
        echo "Import failed"
        exit 1
    fi
    echo
    echo "Import complete"

    # no network interface included in the image, we need to create one based on network uuid set by user earlier
    xe vif-create network-uuid="$vifuuid" vm-uuid="$uuid" device=0 >/dev/null

    # VM startup script reads network details from xenstore and configures interface based on that so set values based on user input earlier
    if [[ "$ipaddress" != "dhcp" ]]; then
        xe vm-param-set uuid="$uuid" xenstore-data:vm-data/ip="$ipaddress" xenstore-data:vm-data/netmask="$netmask" xenstore-data:vm-data/gateway="$gateway" xenstore-data:vm-data/dns="$dns"
    fi

    # remove all other boot options except disk to speed startup
    xe vm-param-remove uuid="$uuid" param-name=HVM-boot-params param-key=order
    xe vm-param-set uuid="$uuid" HVM-boot-params:"order=c"

    echo
    echo "Starting VM..."
    xe vm-start uuid="$uuid"

    set +e

    # loop max 300 seconds for VM to startup and xen tools to announce ip-address value
    count=0
    limit=10
    ip=$(xe vm-param-get uuid="$uuid" param-name=networks param-key=0/ip 2>/dev/null)
    while [[ -z "$ip" ]] && [[ "$count" -lt "$limit" ]]; do
        echo "Waiting for VM to start and announce it got IP-address"
        sleep 30
        ip=$(xe vm-param-get uuid="$uuid" param-name=networks param-key=0/ip 2>/dev/null)
        ((count++))
    done

    # network details are needed in xenstore only during first startup so remove them at this point since VM should be running
    if [[ "$ipaddress" != "dhcp" ]]; then
        xe vm-param-remove param-name=xenstore-data param-key=vm-data/ip uuid="$uuid" 2>/dev/null
        xe vm-param-remove param-name=xenstore-data param-key=vm-data/netmask uuid="$uuid" 2>/dev/null
        xe vm-param-remove param-name=xenstore-data param-key=vm-data/gateway uuid="$uuid" 2>/dev/null
        xe vm-param-remove param-name=xenstore-data param-key=vm-data/dns uuid="$uuid" 2>/dev/null
    fi

    # if we got ip-address value from VM, we print how to access it...
    if [[ "$ip" != "" ]]; then
        echo
        echo "VM Started successfully"
        echo
        echo "You can access Xen Orchestra at https://$ip and via SSH at $ip"
        echo "Default credentials for UI: admin@admin.net/admin"
        echo "Default credentials for SSH: xo/xopass"
        echo
        echo "Remember to change both passwords before putting VM to use!"
    # ... and print the same without ip-address information if ip-address value was missing
    else
        echo
        echo "VM started but we couldn't fetch it's ip-address from xentools"
        echo
        echo "Check VM status/ip-address manually. If VM started correctly, it should have Web UI and SSH accessible at it's ip-address"
        echo "Default credentials for UI: admin@admin.net/admin"
        echo "Default credentials for SSH: xo/xopass"
        echo
        echo "Remember to change both passwords before putting VM to use!"
    fi

}

# run all functions in a specific order
OSCheck
StorageChoose
NetworkChoose
NetworkSettings
VMImport