#!/bin/bash
#  $HeadURL$ $LastChangedRevision$

#  Properties
MY_ID=system_boot_net_pxe
PARENT_ID=system_boot_net
MY_PRIVATE_ATTRIBUTES="uname status"
MY_PUBLIC_ATTRIBUTES=
MY_ATTRIBUTES="$MY_PRIVATE_ATTRIBUTES $MY_PUBLIC_ATTRIBUTES"
MY_HELPER_IDS=
for MY_ATTRIBUTE in ${MY_ATTRIBUTES^^}; do eval "$MY_ATTRIBUTE="; done

#  Defaults for the questions we ask (should only used here)

#  Hooks
create_prologue()
{
    #  my attributes
    inherit MY_ATTRIBUTES ${MY_ATTRIBUTES^^} 
    #  those inherited attributes i will use
    inherit RELEASE ARCH KERNEL_COMMANDLINE MACADDR
    #  real local
    local TFTP_ROOTDIR
    #  make sure MODROOT is set
    inherit MODROOT

    #  Sanity checks and derivations
    helper_sanity_checks_and_derivations

    #  Guts
    info "creating PXE config file ..."
    {
        echo "default linux"
        echo "prompt 0"
        echo "timeout 30"
        echo
        echo "label linux"
        echo "    kernel pxe-images/linux_$RELEASE-$ARCH"
        #  Beware that these kernel command line arguments are also in vm-editor (where
        #  they are only used for PVs, though the netcfg/dhcp_timeout is really only for
        #  PVs which get to doing an DHCP request so much faster)
        echo "    append ipv6.disable=1 initrd=pxe-images/initrd.gz_$RELEASE-$ARCH $KERNEL_COMMANDLINE"
    } > $TFTP_ROOTDIR/pxelinux.cfg/01-${MACADDR//:/-}

    #  Update /srv/tftp/pxe-images (it will not accept a symlink to ~/opt/mdi/lib/pxe-images
    #  and I'm always forgetting that, having updated an image in ~/opt/mdi/lib/pxe-images
    #  that that's not enough).
    rsync -a --delete $MODROOT/lib/pxe-images/ $TFTP_ROOTDIR/pxe-images/
    
    return 0
}

delete_epilogue()
{
    #  my attributes
    inherit MY_ATTRIBUTES ${MY_ATTRIBUTES^^} 
    #  those inherited attributes i will use
    inherit MACADDR
    #  real local
    local TFTP_ROOTDIR

    #  Sanity checks and derivations
    helper_sanity_checks_and_derivations

    #  Guts
    info "deleting PXE config file ..."
    #  rememeber, delete functions are not allowed to fail; hence -f
    RM_OUTPUT=$(rm -f $TFTP_ROOTDIR/pxelinux.cfg/01-${MACADDR//:/-} 2>&1) || warning "rm: failed (output was: $RM_OUTPUT)"

    return 0
}

list_prologue()
{
    #  list functions do not use attributes
    #  real local
    local UNAMES TFTP_ROOTDIR

    #  Sanity checks and derivations
    helper_sanity_checks_and_derivations

    #  Fake guts - to be removed
    UNAMES=$($SQLITE_CMD $DB_FILE "select group_concat(uname,' ') from attribute_values where helper == '$MY_ID' and attribute == 'status' and value == 'installing';")
    debug 10 "list_prologue: the following hosts are marked installing: $UNAMES"

    #  Guts
    echo "PXE config files"
    echo "================"
    echo
    ls -l $TFTP_ROOTDIR/pxelinux.cfg/01-* 2>/dev/null || true
    echo
}

#  Support functions
helper_sanity_checks_and_derivations()
{
    #  we will set this for the caller
    inherit TFTP_ROOTDIR
    #  real local
    local TFTPSERVER_RELEASE

    #  Sanity checks and derivations
    debug 10 "helper_sanity_checks_and_derivations: checking what TFTP root is ..."
    get_release_by_inspection TFTPSERVER_RELEASE || return $?

    #  Guts
    case $TFTPSERVER_RELEASE in
        lenny)   TFTP_ROOTDIR=/var/lib/tftpboot ;;
        squeeze) TFTP_ROOTDIR=/srv/tftp ;;
        wheezy)  TFTP_ROOTDIR=/srv/tftp ;;
        *)       internal "$TFTPSERVER_RELEASE: unhandled" ;;
    esac
}