#!/bin/bash

set -e

COREOS_VERSION=444.0.0
BASE_URL="http://storage.core-os.net/coreos/amd64-usr/$COREOS_VERSION"

KERNEL="/boot/coreos/vmlinuz"
INITRD_IMAGE="/boot/coreos/initrd.cpio.gz"
INITRD_TEMPLATE="/boot/coreos/initrd.template"
CONFIG_LINK_DIR="/boot/coreos/initrd.template/usr/share/oem"

if [ "$1" = "-d" -o "$1" = "--download" ]; then
  shift
  REDOWNLOAD_KERNEL=1
  REDOWNLOAD_INITRD=1
fi

mkdir -p "$CONFIG_LINK_DIR"

cp -avx /usr/share/oem/* "$CONFIG_LINK_DIR"

if [ ! -s "$KERNEL" ]; then
  REDOWNLOAD_KERNEL=1
fi

if [ "$(find "$INITRD_TEMPLATE" -name "*.squashfs" -type f -size +0 | wc -l)" -eq 0 ]; then
  REDOWNLOAD_INITRD=1
fi

if [ -n "$REDOWNLOAD_KERNEL" ]; then
  curl --retry 10 -f "$BASE_URL/coreos_production_pxe.vmlinuz" > "$KERNEL"
fi

if [ -n "$REDOWNLOAD_INITRD" ]; then
  find "$INITRD_TEMPLATE" -name "*.squashfs" -type f -delete

  TMP=`mktemp -d`
  pushd "$TMP" >/dev/null
    curl --retry 10 -f "$BASE_URL/coreos_production_pxe_image.cpio.gz" | zcat | cpio -id
    test ${PIPESTATUS[0]} -eq 0
    find "$TMP" -name "*.squashfs" -type f -exec 'mv' '{}' "${INITRD_TEMPLATE}/" ';'
  popd >/dev/null
  rm -rf "$TMP"
fi


rm -f "$INITRD_IMAGE"

pushd "$INITRD_TEMPLATE" >/dev/null
  rm -f ./manifest
  find . -name "*.squashfs" >> ./manifest
  find ./usr >> ./manifest
  cat ./manifest | cpio -o -H newc -L | gzip -nc - > "$INITRD_IMAGE"
popd >/dev/null