#!/bin/bash
B="http://kernel.ubuntu.com/~kernel-ppa/mainline/"
if [ -z "$1" ]; then
  # identify latest version
  V="$(wget -O - $B 2>/dev/null | grep '[DIR]' | sed 's/.*a href="\(.*\)">v.*/\1/' | tail -1)"
else
  if ! wget -O - "$B/$1" 2>/dev/null >&2; then
    echo "error: Cannot find version $1 in the Ubuntu mainline kernel archive" >&2
    exit 1
  fi
  V="$1/"
fi
mkdir -p $V && pushd $V >/dev/null || exit 1
# fetch each Debian package in the version's directory
for U in $(wget -O - $B$V 2>/dev/null | sed -n 's/.*a href="\(linux.*\(i386\|amd64\|all\)\.deb\)">.*/\1/p'); do
  if [ ! -f $U ]; then
    wget $B$V$U;
  else
    echo "info: skipping download; already have $V$U"
  fi
done
popd
sudo dpkg -i $V/*generic*$(dpkg --print-architecture).deb $V/*_all.deb