#!/usr/bin/bash
# Push VM-Disk-Image on server
set -eu

show_help() {
    cat << EOF >&2
Usage: $(basename "$0") [-u vmname] [-d vmname] [-a] [-t]"
When using option -u (upload), the disk from VM vmname will be synced on server.
Otherwise the images from images.list and xml-directory will be synced from server.
Using flag -t all torrents and xml-VM-Definitions will be synced
EOF
}

VM_DIR="/tmp/${SUDO_UID}/vmimages"

upload_image() {
    # check if VM-Diskimage exists
    if [[ ! (-f "/var/lib/libvirt/images/${VM_NAME}.qcow2" || -f "${VM_DIR}/${VM_NAME}.qcow2") ]]; then
        echo "File not found ${VM_NAME}.qcow2" >&2
        exit 1
    fi
    # link private VM-Diskimage to system-Dir
    if [[ -f "${VM_DIR}/${VM_NAME}.qcow2" \
          &&   ( -f "/var/lib/libvirt/images/${VM_NAME}.qcow2" && ("${VM_DIR}/${VM_NAME}.qcow2" -nt "/var/lib/libvirt/images/${VM_NAME}.qcow2") \
          || ! -f "/var/lib/libvirt/images/${VM_NAME}.qcow2") ]]; then
      echo "copy private VM-Diskimage to system-dir"
      ln -f "${VM_DIR}/${VM_NAME}.qcow2" "/var/lib/libvirt/images/${VM_NAME}.qcow2"
    fi
    # check if VM-Machine-Definition XML exists
    if [[ ! (-f "/var/lib/libvirt/images/xml/${VM_NAME}.xml" || -f "${VM_DIR}/xml/${VM_NAME}.xml") ]]; then
        echo "File not found ${VM_NAME}.xml" >&2
        exit 1
    fi
    # copy private VM-Maschine-Definition XML to system-Dir
    if [[ -f "${VM_DIR}/xml/${VM_NAME}.xml" \
          &&   ( -f "/var/lib/libvirt/images/xml/${VM_NAME}.xml" && $(cmp -s "${VM_DIR}/xml/${VM_NAME}.xml" "/var/lib/libvirt/images/xml/${VM_NAME}.xml") \
          || ! -f "/var/lib/libvirt/images/xml/${VM_NAME}.xml") ]]; then
      echo "copy private VM-Maschine-Definition XML to system-dir"
      cp "${VM_DIR}/xml/${VM_NAME}.xml" "/var/lib/libvirt/images/xml/"
    fi
    # (re-) create torrent file
    /usr/local/bin/vmimage-torrent create "${VM_NAME}.qcow2"
    # Upload Torrent, qcow2 and machine-definition-XML
    [[ -f "/var/lib/libvirt/images/${VM_NAME}.qcow2.torrent" ]] && rsync -av --password-file=/etc/rsync.secret \
	  "/var/lib/libvirt/images/${VM_NAME}.qcow2.torrent" rsync://vmuser@server:/vmimages-upload/
    rsync -av --password-file=/etc/rsync.secret "/var/lib/libvirt/images/${VM_NAME}.qcow2" \
	  rsync://vmuser@server:/vmimages-upload/
    rsync -av --password-file=/etc/rsync.secret "/var/lib/libvirt/images/xml/${VM_NAME}.xml" \
	  rsync://vmuser@server:/vmimages-upload/xml/
}

download_image() {
    if [[ -f "/var/lib/libvirt/images/${VM_NAME}.qcow2.torrent" ]]; then
      cd /var/lib/libvirt/images
      ctorrent -e 0 "${VM_NAME}.qcow2.torrent"
      /usr/local/bin/vmimage-torrent restart "${VM_NAME}.qcow2"
    else 
      rsync -av --password-file=/etc/rsync.secret \
	  "rsync://vmuser@server:/vmimages-download/${VM_NAME}.qcow2" \
	  /var/lib/libvirt/images/
      rsync -av --password-file=/etc/rsync.secret \
	  "rsync://vmuser@server:/vmimages-download/xml/${VM_NAME}.xml" \
	  /var/lib/libvirt/images/xml/
    fi
}

sync_all_images() {
    rsync -av --password-file=/etc/rsync.secret --files-from=/var/lib/libvirt/images/images.list \
	  rsync://vmuser@server:/vmimages-download/ /var/lib/libvirt/images/
    rsync -av --password-file=/etc/rsync.secret rsync://vmuser@server:/vmimages-download/xml \
	  /var/lib/libvirt/images/
}

sync_all_torrents() {
    rsync -av --password-file=/etc/rsync.secret rsync://vmuser@server:/vmimages-download/*.torrent \
	  /var/lib/libvirt/images/
    rsync -av --password-file=/etc/rsync.secret rsync://vmuser@server:/vmimages-download/xml \
	  /var/lib/libvirt/images/
}

while getopts ':u:d:at' OPTION; do
    case "$OPTION" in
        u)
            VM_NAME=$OPTARG
            upload_image
            ;;
        d)
            VM_NAME=$OPTARG
            download_image
            ;;
        a)
            sync_all_images
            ;;
        t)
            sync_all_torrents
            ;;
        ?)
        show_help
        exit 1
        ;;
    esac
done