#!/bin/bash
# Shell functions for common operations using fbwhiptail
. /etc/functions

# Pause for the configured timeout before booting automatically.  Returns 0 to
# continue with automatic boot, nonzero if user interrupted.
pause_automatic_boot()
{
	if IFS= read -t "$CONFIG_AUTO_BOOT_TIMEOUT" -s -n 1 -p \
		"Automatic boot in $CONFIG_AUTO_BOOT_TIMEOUT seconds unless interrupted by keypress... "; then
		return 1 # Interrupt automatic boot
	fi
	return 0 # Continue with automatic boot
}

mount_usb()
{
  TRACE_FUNC
  # Unmount any previous USB device
  if grep -q /media /proc/mounts ; then
    umount /media || die "Unable to unmount /media"
  fi
  # Mount the USB boot device
  mount-usb && USB_FAILED=0 || ( [ $? -eq 5 ] && exit 1 || USB_FAILED=1 )
  if [ $USB_FAILED -ne 0 ]; then
    whiptail $BG_COLOR_ERROR --title 'USB Drive Missing' \
      --msgbox "Insert your USB drive and press Enter to continue." 0 80
    mount-usb && USB_FAILED=0 || ( [ $? -eq 5 ] && exit 1 || USB_FAILED=1 )
    if [ $USB_FAILED -ne 0 ]; then
      whiptail $BG_COLOR_ERROR --title 'ERROR: Mounting /media Failed' \
        --msgbox "Unable to mount USB device" 0 80
      exit 1
    fi
  fi
}

# Create display text for a size in bytes in either MB or GB, unit selected
# automatically, rounded to nearest
display_size() {
	local size_bytes unit_divisor unit_symbol
	size_bytes="$1"

	# If it's less than 1 GB, display MB
	if [ "$((size_bytes))" -lt "$((1024*1024*1024))" ]; then
		unit_divisor=$((1024*1024))
		unit_symbol="MB"
	else
		unit_divisor=$((1024*1024*1024))
		unit_symbol="GB"
	fi

	# Divide by the unit divisor and round to nearest
	echo "$(( (size_bytes + unit_divisor/2) / unit_divisor )) $unit_symbol"
}

# Create display text for the size of a block device using MB or GB, rounded to
# nearest
display_block_device_size() {
	local block_dev disk_size_bytes
	block_dev="$1"

	# Obtain size of thumb drive to be wiped with fdisk
	if ! disk_size_bytes="$(blockdev --getsize64 "$block_dev")"; then
		exit 1
	fi

	display_size "$disk_size_bytes"
}

# Display a menu to select a file from a list.  Pass the name of a file
# containing the list.
# --show-size: Append sizes of files listed.  Currently only supports block
#   devices.
# $1: Name of file listing files that can be chosen (one per line)
# $2: Optional prompt message
# $3: Optional prompt title
#
# Success: Sets FILE with the selected file
# User aborted: Exits successfully with FILE empty
# No entries in list: Displays error and exits unsuccessfully
file_selector()
{
	TRACE_FUNC

	local FILE_LIST MENU_MSG MENU_TITLE CHOICE_ARGS SHOW_SIZE OPTION_SIZE option_index

	FILE=""

	if [ "$1" = "--show-size" ]; then
		SHOW_SIZE=y
		shift
	fi

	FILE_LIST=$1
	MENU_MSG=${2:-"Choose the file"}
	MENU_TITLE=${3:-"Select your File"}

	CHOICE_ARGS=()
	n=0
	while read option; do
		n="$((++n))"

		if [ "$SHOW_SIZE" = "y" ] && OPTION_SIZE="$(display_block_device_size "$option")"; then
			option="$option - $OPTION_SIZE"
		fi
		CHOICE_ARGS+=("$n" "$option")
	done < "$FILE_LIST"

	if [ "${#CHOICE_ARGS[@]}" -eq 0 ]; then
		whiptail $BG_COLOR_ERROR --title 'ERROR: No Files Found' \
			--msgbox "No Files found matching the pattern. Aborting." 0 80
		exit 1
	fi

	CHOICE_ARGS+=(a Abort)

	# create file menu options
	option_index=""
	while [ -z "$option_index" ]; do
		whiptail --title "${MENU_TITLE}" \
			--menu "${MENU_MSG} [1-$n, a to abort]:" 20 120 8 \
			-- "${CHOICE_ARGS[@]}" \
			2>/tmp/whiptail || die "Aborting"

		option_index=$(cat /tmp/whiptail)

		if [ "$option_index" != "a" ]; then
			FILE="$(head -n "$option_index" "$FILE_LIST" | tail -1)"
		fi
	done
}

show_system_info()
{
  TRACE_FUNC
  battery_charge="$(print_battery_charge)"
  battery_health="$(print_battery_health)"
  if [ -n $battery_charge -a -n $battery_health ];then
	  battery_status="\nBattery charge: $battery_charge%\nBattery health: $battery_health%\n"
  fi

  memtotal=$(cat /proc/meminfo | grep 'MemTotal' | tr -s ' ' | cut -f2 -d ' ')
  memtotal=$((${memtotal} / 1024 / 1024 + 1))
  cpustr=$(cat /proc/cpuinfo | grep 'model name' | uniq | sed -r 's/\(R\)//;s/\(TM\)//;s/CPU //;s/model name.*: //')
  kernel=$(uname -s -r)

  whiptail $BG_COLOR_MAIN_MENU --title 'System Info' \
    --msgbox "${BOARD_NAME}\n\nFW_VER: ${FW_VER}\nKernel: ${kernel}\n\nCPU: ${cpustr}\nRAM: ${memtotal} GB\n$battery_status\n$(fdisk -l | grep -e '/dev/sd.:' -e '/dev/nvme.*:' | sed 's/B,.*/B/')" 0 80
}

# Get "Enable" or "Disable" to display in the configuration menu, based on a
# setting value
get_config_display_action()
{
  [ "$1" = "y" ] && echo "Disable" || echo "Enable"
}

# Invert a config value
invert_config()
{
  [ "$1" = "y" ] && echo "n" || echo "y"
}

# Get "Enable" or "Disable" for a config that internally is inverted (because it
# disables a behavior that is on by default).
get_inverted_config_display_action()
{
  get_config_display_action "$(invert_config "$1")"
}