#!/bin/bash
# Description: This simple Scripts creates an Virtualmachine on Proxmox, with the Qemu-Cli.
# Usage: Just Execute the script, it's a guided Script (chmod +x CreateCloudInitVM.sh && ./ CreateCloudInitVM.sh)
#
# Creator: Janic Joël Voser, Mettmenstetten - CH
# Date of Creation: 03.12.2021
#
# Active Maintainer: Janic Joël Voser
# Date of Last Maintenance: 03.12.2021
#
# Current State: Development
# Version: 1.0.0
# Version History:
# v0.0.1 - Basic Script Structure
# v0.1.0 - Get the User input
# v0.2.0 - Gather Virtual Machine ID
# v0.3.0 - Get & Select the Image of the Virtualmachine
# v0.4.0 - Create the VM & Gather additional Information
# v0.5.0 - Add proper Comments
# v1.0.0 - First Properly Working Version

# Planned Features:
#   - [X] Guided VM Creation
#   - [X] Image Download URL
#   - [X] Image Selection
#   - [X] VM-ID check
#   - [X] Choose Memorysize
#   - [X] Choose CPU cores
#   - [X] Choose Network
#   - [X] IMG & ISO & qcow2 support

# Global Constants
IMAGE_STORAGE_LOCATION="/var/lib/vz/template/iso/" # Enter here the location of your iso-Templates - This is not adjustable while running the script
DEFAULT_VM_STORAGE="tank-vms" # Enter here the default Storage Location, so you can Skip it by pressing enter
DEFAULT_DOWNLOAD_IMG_yn="n" # Set the default value for the "Download new Image"-Questing
DEFAULT_VM_NAME="cloudinit-vm" # Set the default value for the Virtual Machine Name
DEFAULT_VM_RAM="2048" # Set the default value of Memory for the Virtual Machine
DEFAULT_VM_CORES="2" # Set the default amount of cpu-cores for the Virtual Machine
DEFAULT_VM_NET="vmbr0" # Set the default network interface for the Virtual Machine

# Functions
## Gather the ID of the Virtual machine
function gather_vmid {
    echo "Already used IDs"
    qm list | tr -s ' ' | cut -d ' ' -f 2,3 # Get the already used VMIDs & VM-Name
    echo "Enter the new ID of your Virtual Machine (It must be unused)"
    read VM_ID # Get the User Input(This VMID will be used for the new created VM)
    readarray -t VMID_ARRAY < <(qm list | tail -n +2 | tr -s ' ' | cut -d ' ' -f 2)
    if [[ "${VMID_ARRAY[*]}" =~ "$VM_ID" ]]; then # Check if Virtual Machine ID is alredy in use
        echo "Your selected Virtual Machine ID is already in use, choose an other ID"
        gather_vmid
    fi
}
## Download a new Image in to the Image Storage
function get_img {
    echo "Do you wish to download an Image? (yes/no)"
    read DOWNLOAD_IMG_yn
    case "${DOWNLOAD_IMG_yn:=DEFAULT_DOWNLOAD_IMG_yn}" in # Case Statement to switch based on the User Input
        yes|YES|Yes|y|Y) # The Yes case enables the possibility to download an Image
            echo "Please enter the URL of your Image"
            read DOWNLOAD_IMG_URL
            wget "$DOWNLOAD_IMG_URL" --directory-prefix="$IMAGE_STORAGE_LOCATION" # Download the Image in to the default Image-Storage
            if [ $? -eq 0 ]; then # Check if last command (Download) was successful
                echo "Download was Successful"
            else 
                echo "Download failed"
                echo "Retry or Downloadfile manually"
                get_img
            fi
            ;;
        no|NO|No|n|N) # The No Case skips the Image Download step
            echo "Carrying on without a new Image"
            ;;
        *)
            echo "Invalid Argument: Please type \"yes\" or \"no\""
            get_img # Question again if the Answer was not an possible Option
            ;;
    esac
}
## Select an Image
function sel_img {
    echo "The following list represents all Images which exist on the Hoststorage"
    ls $IMAGE_STORAGE_LOCATION -l | tr -s ' ' | cut -d' ' -f 6-9 # List all files in the Image Location and their Age of Creation
    readarray -t OS_IMG_ARRAY < <(ls $IMAGE_STORAGE_LOCATION -l | tr -s ' ' | cut -d' ' -f 9) # Create an Array of all Images
    echo "Please enter the correct Image Name(shown above)"
    read OS_IMG_NAME
    if ! [[ "${OS_IMG_ARRAY[*]}" =~ "$OS_IMG_NAME" ]]; then # Check if Selected Image is in the Array, else go back to the selection
        echo "Your selected Image does not exist"
        echo "Maybe it was a Typo, Please check:"
        echo " - Upper/Lowercase writing"
        echo " - Fileextension(needs to be appended)"
        echo "ProTip: Copy & Paste"
        sleep 3
        sel_img
    fi
}
## Get the prepared Cloud-Init Image
function gather_img {
    get_img
    sel_img
}
## Gather Virtualmachine Network
function gather_vm_net {
    ip -o link show | awk -F': ' '{print $2}' | grep vmbr # Get all the Virtual Bridge Interfaces of the Hostsystem
    echo "Enter one of the above shown Network-Interfaces to add to your VM"
    read VM_NET
    readarray -t VM_NET_ARRAY < <(ip -o link show | awk -F': ' '{print $2}' | grep vmbr) # Create an array of all Virtual Bridge Interfaces of the Hostsystem
    if ! [[ "${VM_NET_ARRAY[*]}" =~ "$VM_NET" ]]; then # Check if Selected Network is an existing network else go back to the Selection
        echo "Your selected Network does not exist"
        echo "Maybe it was a Typo, Please check:"
        echo " - Upper/Lowercase writing"
        echo "ProTip: Copy & Paste"
        sleep 3
        gather_vm_net
    fi
}
## Gather hardware
function gather_hardware {
    echo "Enter the amount of memory in MegaBytes"
    echo "Example for 2GB = \"2048\""
    read VM_RAM
    echo "Enter the amount of Cpu-Cores you want to give to the Virtual machine"
    read VM_CORES
    gather_vm_net
}
## Gather all aditional Data
function gather_additional {
    gather_vmid
    echo "Enter the name of the new Virtualmachine"
    read VM_NAME

}
## Gather VM_Storage
function gather_vm_storage {
    echo "Please enter the Virtual Machine Storage Pool:[$DEFAULT_VM_STORAGE]"
    read VM_STORAGE
    VM_STORAGE=${VM_STORAGE:=$DEFAULT_VM_STORAGE} # Get the Storage of the VM, if nothing is set just use the Default
}
## Get all the Variables from the User
function get_user_input {
    gather_img
    gather_hardware
    gather_vm_storage
    gather_additional
}
# Import the Cloudinit image and append it to the Virtual Machine
function vm_import_cloudinit_img {
    IMG_TYPE=$(echo "$OS_IMG_NAME" | rev | cut -d "." -f 1 | rev) # Get the Image Fileending for further operations
    if [ $IMG_TYPE == "iso" ] || [ $IMG_TYPE == "img" ];then # If the Image Fileending is "iso" or img" do the following
        qm importdisk "$VM_ID" "$IMAGE_STORAGE_LOCATION$OS_IMG_NAME" "$VM_STORAGE" -format qcow2 # Convert the Image to qcow2 format and write it to the VM-Storage
        if ! [ $? -eq 0 ];then
            echo "It was not possible to convert a new Image with your values"
            echo "Read the error message above"
            exit
        fi
    elif [ $IMG_TYPE == "qcow2" ];then # If the Image Fileending is "qcow2" do the following
        qm importdisk "$VM_ID" "$IMAGE_STORAGE_LOCATION$OS_IMG_NAME" "$VM_STORAGE" #import a copy of the Image to the VM, safe the copy in the set Storagepath
        if ! [ $? -eq 0 ];then 
            echo "It was not possible to convert a new Image with your values"
            echo "Read the error message above"
            exit
        fi
    else 
        echo "Your OS-Image does not have a fileending which is supported by this scirpt"
        echo "only iso & img are Supported"
        exit
    fi
}
# Create the Virtual Machine with Set-Values
function create_qm_vm {
    qm create "$VM_ID" --name "${VM_NAME:=$DEFAULT_VM_NAME}" --memory "${VM_RAM:=$DEFAULT_VM_RAM}" --cores "${VM_CORES:=$DEFAULT_VM_CORES}" --net0 virtio,bridge="${VM_NET:=$DEFAULT_VM_NET}" # Create the Virtualmachine with the set hardware specification
    if ! [ $? -eq 0 ];then
        echo "It was not possible to create a Virtual machine with your values"
        echo "Read the error message above"
        exit
    fi
    vm_import_cloudinit_img # Import the Image to the Virtual Machine
    qm set $VM_ID --scsihw virtio-scsi-pci --scsi0 $VM_STORAGE:vm-$VM_ID-disk-0 #Add the Image to  the Virtual Machine
    if ! [ $? -eq 0 ];then
        echo "It was not possible to add the custom Image to your Virtual machine"
        echo "Read the error message above"
        exit
    fi
    qm set $VM_ID --ide2 $VM_STORAGE:cloudinit --boot c --bootdisk scsi0 --serial0 socket --vga serial0 #Add the Cloud-Initdrive & set the Bootdrive & Add a serial console(is needed for cloud-init)
    if ! [ $? -eq 0 ];then
        echo "It was not possible to add an cloudinit drive to your Virtual machine"
        echo "Read the error message above"
        exit
    fi
}
# Main Script
get_user_input
create_qm_vm
echo "Script was Successful"
echo "Have fun with your newly deployed Virtual Machine"