#!/bin/sh

###########################################################################
#
# Copyright (c) 2021-2023 Diality Inc. - All Rights Reserved.
#
# THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
# WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
#
# @file    decommission.sh
#
# @author  (last)      Vy Duong
# @date    (last)      26-May-2023
# @author  (original)  Vy Duong
# @date    (original)  26-May-2023
#
############################################################################

# @details
#  This file is called by UI Software to decommission the device

if [ $# -eq 0 ]; then
    currentFile=$(basename "$0")
    echo "Usage: ./$currentFile <cloudsync token path>"
    exit 1
fi

ERR_FAILED_RM_WIFI_CONF=150
ERR_FAILED_CLEAR_BT_CACHE=151
ERR_FAILED_RESET_SETTINGS_CONF=152
ERR_FAILED_CLEAR_LOGS=153
ERR_FAILED_RM_SSH=154
ERR_FAILED_CLEAR_CLOUDSYNC_TOKEN=155


LOC_CLOUDSYNC_TOKEN=%1
LOC_SETTINGS_CONF="/home/root/.config/Settings/System.conf"
LOC_DEFAULT_SETTINGS_CONF="/home/root/scripts/default_settings.conf" #TODO update to reflect real location
LOC_WIFI_CONF="/etc/wpa_supplicant/wpa_supplicant-wlan0.conf"
LOC_BLUETOOTH_CACHE_FOLDER="/var/lib/bluetooth/"
LOC_SSH_FOLDER="$HOME/.ssh/"
LOC_LOG_PARENT_FOLDER="/media/sd-card/"

# removes all the files in the directory and subdirectory in a recursive manner
# exits with passed error code if either rm command fails or folder is not empty of files
# %1 - Directory path
# %2 - Error message string/msg
# %3 - Error code to return on exit in case of error
function clearFolderContent() {
    if [ -f $1 ]; then
        rm -rf "$1/*/*"
    fi

    rmCommandReturn=$?
    fileCount=$(find $1 -type f | wc -l)
    
    if [ "$fileCount" -ne 0 ] || [ "$rmCommandReturn" -ne 0 ]; then 
        echo "Error : $2 ($fileCount)" 
        exit $3
    fi
}

# Removes a single file
# exits with passed error code if either rm command fails or if file was not removed
# %1 - path to file
# %2 - Error message string/msg
# %3 - Error code to return on exit in case of error
function removeSingleFile() {
    if [ -f $1 ]; then
            rm "$1"
    fi
    if [ -f $1 ]; then
        echo "Error: $2"
        # the file still exists, exit with error message
        exit $3
    fi
}

# ==== For encrypted partition ====
ERR_CRYPTSETUP_USAGE=101
ERR_CRYPTSETUP_PASSWORD=102

ERR_CRYPTSETUP_CREATE_MKDIR=121
ERR_CRYPTSETUP_CREATE_FORMAT=122
ERR_CRYPTSETUP_CREATE_OPEN=123
ERR_CRYPTSETUP_CREATE_MKFS=124
ERR_CRYPTSETUP_CREATE_MOUNT=125
ERR_CRYPTSETUP_UNMOUNT_UNMOUNT=126
ERR_CRYPTSETUP_UNMOUNT_CLOSE=127

LOC_DEV="/dev/mmcblk0p7"
LOC_DIR="configurations"
LOC_MAP="/dev/mapper/"$LOC_DIR
LOC_VAR="/var/"$LOC_DIR
  	
function checkPassword() {
    if [ "$PASSWORD" == "" ]; then
        echo "Error : Setup command missing password argument"
        exit $ERR_CRYPTSETUP_PASSWORD
    fi
}

function checkOutput() {
    if [ "$3" == "" ]; then
        out=`          eval "$1" 2>&1`
    else
        out=`echo $3 | eval "$1" 2>&1`
    fi
    if [ "$?" -ne 0 ]; then
        echo $out
        exit $2
    fi
}

function unmount_luks_partition()
{
  	checkOutput "umount               $LOC_VAR          " $ERR_CRYPTSETUP_UNMOUNT_UNMOUNT
    checkOutput "cryptsetup luksClose $LOC_DIR          " $ERR_CRYPTSETUP_UNMOUNT_CLOSE
}

function create_luks_partition()
{
    umount_luks_partition
    
    checkOutput "mkdir      -p         $LOC_VAR         " $ERR_CRYPTSETUP_CREATE_MKDIR
    checkOutput "cryptsetup luksFormat $LOC_DEV         " $ERR_CRYPTSETUP_CREATE_FORMAT     $PASSWORD
    checkOutput "cryptsetup luksOpen   $LOC_DEV $LOC_DIR" $ERR_CRYPTSETUP_CREATE_OPEN       $PASSWORD
    checkOutput "mkfs.ext4             $LOC_MAP         " $ERR_CRYPTSETUP_CREATE_MKFS
    checkOutput "mount      -t ext4    $LOC_MAP $LOC_VAR" $ERR_CRYPTSETUP_CREATE_MOUNT
}

# ------------------------------ Remove Wifi Conf
removeSingleFile $LOC_WIFI_CONF "Failed to remove WiFi conf file" $ERR_FAILED_RM_WIFI_CONF

# ------------------------------ Remove Bluetooth cache
clearFolderContent $LOC_BLUETOOTH_CACHE_FOLDER "Failed to remove Bluetooth cache" $ERR_FAILED_CLEAR_BT_CACHE

# ------------------------------ Reset Settings Conf
cp $LOC_DEFAULT_SETTINGS_CONF $LOC_SETTINGS_CONF

# ------------------------------ Remove Logs
#TODO this will always fail due to the fact UI is not pausing on it's writing of log when we attempt a removal, causing the count to always be >0
clearFolderContent $LOC_LOG_PARENT_FOLDER "Failed to remove logs" $ERR_FAILED_CLEAR_LOGS

# ------------------------------ Format Encrypted Partition
checkPassword 
create_luks_partition

# ------------------------------ Remove CloudSync Token
clearFolderContent $LOC_CLOUDSYNC_TOKEN "Failed to remove CloudSync token" $ERR_FAILED_CLEAR_CLOUDSYNC_TOKEN

# ------------------------------ Remove ssh
clearFolderContent $LOC_SSH_FOLDER "Failed to remove ssh" $ERR_FAILED_RM_SSH

exit 0