#!/bin/bash

## COPYRIGHT 2013 : MARK E. LEE (BLUERIDER) : mlee24@binghamton.edu; mark@markelee.com

## LOG
## 1/16/2013 : updates nvram and specfied efi directory ($efi_dir); can also generate $efi_dir
## 1/16/2013 : depends on awk and bash
## 1/16/2013 : $efi_dir must possessess only 4 directories
## 1/16/2013 : currently doesn't copy config files
## 1/16/2013 : fixed copying /usr/share/refind instead of /usr/share/refind/* in update-efi-dir
## 1/16/2013 : added support for detecting if an nvram update is necessary

function main () {  ## main insertion function
  declare -r efi_dir="/boot/efi/EFI/refind"; ## set the refind directory
  ## convert efi_dir to efibootmgr format
  declare -r refind_efi=$(echo ${efi_dir/\/boot\/efi/} | awk -F'/' '{OFS= "\\"; print ($1,$2,$3)}');
  declare -r arch=$(uname -m | awk -F'_' '{if ($1 == "x86"){print $2}}') &&  ## get bit architecture
  update-efi-dir;  ## updates or creates the refind directory
  declare -r ref_bin=$(ls $efi_dir | grep $arch*.efi);  ## get the name of the refind binary
  update-efi-nvram;  ## updates nvram if needed
}

function update-efi-dir () {  ## setup the refind directory
  if [ ! -d $efi_dir ]; then  ## check if refind directory exists
    echo "Couldn't find $efi_dir";
    sudo mkdir $efi_dir &&  ## make the refind directory if needed
    echo "Made $efi_dir";
  fi;
  if [ "$arch" ]; then  ## check if anything was stored in $arch
    sudo cp -r /usr/{share/refind/*,lib/refind/*$arch*} $efi_dir/  && ## update bin and dirs
    echo "Updated binaries and directory files for refind at $efi_dir";
   else
    echo "Failed to detect an x86 architecture";
    exit;
  fi;
}

function update-efi-nvram () { ## update the nvram with efibootmgr
  ## insert escape characters into $refind_efi\$ref_bin
  declare -r awk_efi_patch=$(echo "$refind_efi\\$ref_bin" | awk -F'\' '{OFS = "\\\\"; print ($1,$2,$3,$4)}');
  declare -r boot_entry=$(sudo efibootmgr -v | grep $awk_efi_patch);  ## find the boot entry
  sudo modprobe efivars && ## grab the efi variables for efibootmgr
  if [ -z "$boot_entry" ]; then
    declare -r esp=$(mount -l | awk '/ESP/ {print $1}') &&  ## get ESP partition
    declare -r efiDisk=${esp:0:8} &&  ## get ESP disk
    declare -r efiPart=${esp:8} && ## get ESP partition number
    ## update the nvram with entry "rEFInd"
    sudo efibootmgr -c -g -d $efiDisk -p $efiPart -w -L "rEFInd" -l "$refind_efi\\$ref_bin" &&
    echo "Updated nvram with entry rEFInd to boot $refind_efi\\$ref_bin";
    echo "Did not copy configuration files, please move refind.conf to $efi_dir/";
   else
    echo "Found boot entry, no need to update nvram";
  fi;
}

main;  ## run the main insertion function