#!/bin/bash
#
# 	DESCRIPTION:	install bootloader for OS
#
#	SCRIPT NAME:	install_bootloader.sh
#
#	Input:	
#			[--help]      show this message
#			<-t|--type>      boot loader type:grub,etc.
#	Output:	
#			NULL
#	Return value:
#			1 argument error
#			2 bootloader type doesn't specify
#			3 bootloader no implement
#			127 bootloader utils not found
#
#	AUTHOR:		Qin Bo
#
#	EMAIL:		bqin@linx-info.com
#
#	DATE:		2010-09-02
#
#	HISTORY:
#	REVISOR		DATE			MODIFICATION
#	Qin Bo		2010-09-02		create
#
#
#

source ./functions

usage ()
{
	if [ "$1" == "-n" ];then
		cmd="info"
		ret=0
	else
		cmd="err"
		ret=1
	fi
	$cmd "
This script will install boot loader for system

Usage: $0 options

options:
	[--help]      show this message
	<-t|--type>      boot loader type:grub, etc.
   
   "
   return $ret
}

install_grub ()
{

# generate device.map
grub --batch --no-floppy --device-map="$DEVICEMAP" << EOF 1>>"$DEV_LOG" 2>&1
quit
EOF
	# in order to let bios to load grub correct,
	# we install grub to first hard disk by default,
	# so even though OS install in secondary hard disk,
	# the OS still can be loaded from first hard disk.

	f_hd=$(grep "(hd0)" "$DEVICEMAP"|awk '{print $NF}')

	grub-install --no-floppy --root-directory=$TARGET $f_hd 1>>$DEV_LOG 2>&1
}

# This should probably be rewritten using udevadm or similar.
# from di grub-install
device_to_disk ()
{
    if [ "$(echo $1 |grep '/dev/mapper')"x != x ];then
        if [ "$(echo $1 |grep [0-9]p[0-9]$)"x != x ];then
            echo ${1%p*}
        else
	        echo "$1" |sed 's/\(.*[a-z]\)\(.*\)/\1/'
        fi
    else
        echo "$1" | \
        sed 's:\(/dev/\(cciss\|ida\|rs\)/c[0-9]d[0-9][0-9]*\|/dev/mmcblk[0-9]\|/dev/\(ad\|da\)[0-9]\+\|/dev/[hs]d[0-9]\+\|/dev/[a-z]\+\).*:\1:'
    fi
}

install_grub2()
{
    mount -obind /dev $TARGET/dev
    mount -obind /proc $TARGET/proc
    mount -obind /sys $TARGET/sys

    boot_dev=$(chroot $TARGET grub-probe -t device /boot)
    disk=$(device_to_disk $boot_dev)

    chroot $TARGET update-grub > /dev/null 2>&1
    chroot $TARGET grub-install  $disk --force > /dev/null 2>&1
    chroot $TARGET update-grub > /dev/null  2>&1
}

main ()
{
	if [ $# -eq 0 ];then
		usage; erv
	fi

	tmp=$(getopt -o t: --long type:,help -- "$@" 2>>$DEV_LOG)
	if [ $? -ne 0 ];then
		usage; erv
	fi

	# set all argument to arg variable
	eval set -- "$tmp"

	while true ;do
		case "$1" in
			-t|--type) 
				type="$2" 
				shift 2
			;;
			--help) usage -n; exit 0 ;;
			# shift the last "--", this dash is define by getopt (more information see man getopt)
			--) shift; break;;
			*) usage; erv ;;
		esac
	done

	if [ -n "$type" ];then
		case "$type" in
			grub)
				install_grub
				erv
				;;
			grub2)
				install_grub2
				erv
				;;
			elilo)
				echo "install elilo";
				sed -i '/tmppoint/d' $TARGET/etc/fstab
                umount /tmp/tmppoint
                rm -rf /tmp/tmppoint
				;;
			*)
			
				err "$type bootloader no implement yet !"
				exit 3
				;;
		esac
	else
		err "bootloader type doesn't specify"
		exit 2
	fi
}

GRUB_DIR="$TARGET/boot/grub"
DEVICEMAP="$GRUB_DIR/device.map"

main "$@"