#!/bin/bash

# Creates text file named '@LOG_FILENAME@'
# at the root of the target volume. This is to give the user
# a record of the installation process and also to show why
# possibly the installation process failed (even though the
# package installer ends reading 'Installation Successful').

# This script also prepares the Ram Disk and the InstallConfig.plist
mainLine="=============================================================================="
subLine="------------------------------------------------------------------------------"

if [ "$3" == "/" ]
then
    targetVolume="/Volumes/"$( ls -1F /Volumes | sed -n 's:@$::p' )
else
    targetVolume="$3"
fi

v_mntpt="/Volumes/BOOTRAMDISK"
size='409600' # is the size of a standard EFI partition
logName="@LOG_FILENAME@"
configFile="/private/tmp/InstallConfig.plist"

# Functions to create/umount the RAM DISK
UMOUNT_VDISK() {
        umount -f "${1}"
        hdiutil detach "${1}"
}

RAM_DISK() {
    if [ $( df | awk '{$1=$2=$3=$4=$5=$6=$7=$8=""; print $0}' | \
        sed -e 's/^ *//' | sed -e 's/ *$//' | grep -x "${v_mntpt}" ) ]; then
        devToUmount=$( LC_ALL=C diskutil info "${v_mntpt}" | grep -i 'Device Node:' | awk '{print $3}' )
        UMOUNT_VDISK $devToUmount
    fi
    echo "CREATING RAM DISK"
#    mkdir -p $v_mntpt

    dev=$(hdiutil attach -nomount ram://${size})
    if [ $? -eq 0 ] ; then
        diskutil erasevolume FAT32 "BOOTRAMDISK" ${dev}
    else
        echo "Failed to create the Ram Disk, installation aborted!"
        exit 1
    fi

    dev=$( echo "${dev}" | tr -d " \t\n" )
    rm -f $configFile
    # adding the Ram disk device to InstallConfig.plist to be shared with other packages
    /usr/libexec/PlistBuddy -c "Add :ramdisk  string ${dev}" $configFile
}

RAM_DISK

# ensure that ram disk has "/Volumes/BOOTRAMDISK" mount point
v_mntpt=$( LC_ALL=C diskutil info ${dev} | grep -i 'mount point' | awk '{$1=$2=""; print $0}' | \
                                                             sed -e 's/^ *//' | sed -e 's/ *$//' )
if [ ! -d "${v_mntpt}" ]; then
    echo "Ram Disk not found!"
    exit
fi

touch "${v_mntpt}/${logName}"
exec > >(tee -a "${v_mntpt}/${logName}") 2>&1

echo "$mainLine"
echo "SYSTEM INFO:"
sw_vers
echo "$mainLine"
echo "Pre-Install Script"
echo "$subLine"

# creating a symlink (from Clover)
echo "Creating ${targetVolume}/EXTRAROOTDIR symlink targeting ${v_mntpt}"
ln -sf "${v_mntpt}" "${targetVolume}/EXTRAROOTDIR"

# Preparing Backing up of Chameleon files
backupRootDir="${targetVolume}/Chameleon.Backups"
backupDir=$( date -j "+%F-%Hh%M" )

# Create the backup directory
mkdir -p "${backupRootDir}/${backupDir}"

# Remove the invisible flag of files in the backups
chflags -R nohidden "${backupRootDir}"

# adding the backupdir name to InstallConfig.plist to be shared with other packages
/usr/libexec/PlistBuddy -c "Add :backupDir  string ${backupDir}" $configFile >/dev/null

diskutil list >> "${v_mntpt}/${logName}"
echo "$subLine"
echo "END - Pre-Install Script"

exit 0