#!/bin/bash
#shellcheck disable=SC1091
# wslu - Windows 10 linux Subsystem Utility
# Component of Windows 10 linux Subsystem Utility
# <https://github.com/wslutilities/wslu>
# Copyright (C) 2019 Patrick Wu
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Current utility
wslu_util_fullpath="$0"
wslu_util_name="${wslu_util_fullpath##*/}"

# Version
wslu_version=4.1.10-1
wslu_prefix="/usr"
wslu_dest_dir=""

# Speed up script by using unicode.
LC_ALL=C
LANG=C

# current state location
wslu_state_dir=${XDG_STATE_HOME:-$HOME/.local/state}/wslu
if [ ! -d "$wslu_state_dir" ]; then
  mkdir -p "$wslu_state_dir"
fi

# prevent bash -x
set +x

bash_version_full=$(bash --version | head -n 1)
bash_version_major=$(echo "$bash_version_full" | cut -d ' ' -f 4 | cut -d '.' -f 1)
bash_version_minor=$(echo "$bash_version_full" | cut -d ' ' -f 4 | cut -d '.' -f 2)

# pipeline content to pipe... if it is wslclip
if [[ "$wslu_util_name" == "wslclip" ]]; then
  if [[ -p /dev/stdin ]]; then
    PIPE=$(cat -)
  fi
fi

# conf handling module
__wsl_conf_read() {
  if [ -f /etc/wsl.conf ]; then
    tmp="$(sed -nr "/^\[${1}\]/ { :l /^${2}[ ]*=/ { s/[^=]*=[ ]*//; p; q;}; n; b l;}" /etc/wsl.conf)"
    if [ -n "$tmp" ]; then
      if [ ${#tmp} -ge 2 ]; then
        if [ "${tmp:0:1}" == '"' ] && [ "${tmp: -1}" == '"' ]; then
          echo "${tmp:1:-1}"
        elif [ "${tmp:0:1}" == "'" ] && [ "${tmp: -1}" == "'" ]; then
          echo "${tmp:1:-1}"
        else
          echo "$tmp"
        fi
      else
        echo "$tmp"
      fi
    fi
  fi
}

# checking interopability
if __wsl_conf_read interop enabled | grep false >/dev/null; then
   echo -e "WSL Interopability is disabled and WSL Utilities won't work. Please enable it by:
  1. open /etc/wsl.conf using root or equivalent editing permission;
  2. under [interop] section, set enabled to true;
  3. restart your distribution."
  exit 1
elif [ -f /proc/sys/fs/binfmt_misc/WSLInterop ] && grep -q '^disabled' /proc/sys/fs/binfmt_misc/WSLInterop; then
    echo "WSL Interopability is temporarily disabled and WSL Utilities won't work. Please enable it by:
    # echo 1 > /proc/sys/fs/binfmt_misc/WSLInterop"
    exit 1
elif [ -f /proc/sys/fs/binfmt_misc/WSLInterop-late ] && grep -q '^disabled' /proc/sys/fs/binfmt_misc/WSLInterop-late; then
    echo "WSL Interopability is temporarily disabled and WSL Utilities won't work. Please enable it by:
    # echo 1 > /proc/sys/fs/binfmt_misc/WSLInterop-late"
    exit 1
fi

# when --verbose, verbose; when --debug, debug.
#
# They should not exist at the same time, otherwise
# the output would be too messy.
wslu_debug=""
if [ "$1" == "--verbose" ]; then
  echo -e '\e[38;5;202m\033[1m[verbose] Showing verbose output. \033(B\033[m' 1>&2
  shift
  set -x
elif [ "$1" == "--debug" ]; then
  wslu_debug="--debug"
  echo -e '\e[38;5;202m\033[1m[debug:'"${wslu_util_fullpath}"'] Showing debug output. \033(B\033[m' 1>&2
  shift
fi

# variables
## color
black=$(echo -e '\e[30m')
red=$(echo -e '\e[31m')
green=$(echo -e '\e[32m')
brown=$(echo -e '\e[33m')
blue=$(echo -e '\e[34m')
purple=$(echo -e '\e[35m')
cyan=$(echo -e '\e[36m')
yellow=$(echo -e '\e[33m')
white=$(echo -e '\e[37m')
dark_gray=$(echo -e '\e[1;30m')
light_red=$(echo -e '\e[1;31m')
light_green=$(echo -e '\e[1;32m')
light_blue=$(echo -e '\e[1;34m')
light_purple=$(echo -e '\e[1;35m')
light_cyan=$(echo -e '\e[1;36m')
light_gray=$(echo -e '\e[37m')
orange=$(echo -e '\e[38;5;202m')
light_orange=$(echo -e '\e[38;5;214m')
deep_purple=$(echo -e '\e[38;5;140m')
bold=$(echo -e '\033[1m')
reset=$(echo -e '\033(B\033[m')

## indicator
info="${green}[info]${reset}"
input_info="${cyan}[input]${reset}"
error="${red}[error]${reset}"
warn="${orange}[warn]${reset}"

## Windows build number constant
# Windows 10
readonly BN_SPR_CREATORS=15063		#1703, Redstone 2, Creators Update
readonly BN_FAL_CREATORS=16299		#1709, Redstone 3, Fall Creators Update
readonly BN_APR_EIGHTEEN=17134		#1803, Redstone 4, April 2018 Update
readonly BN_OCT_EIGHTEEN=17763		#1809, Redstone 5, October 2018 Update
readonly BN_MAY_NINETEEN=18362		#1903, 19H1, May 2019 Update
readonly BN_NOV_NINETEEN=18363		#1909, 19H2, November 2019 Update
readonly BN_MAY_TWENTYTY=19041		#2004, 20H1, May 2020 Update
readonly BN_OCT_NINETEEN=19042		#20H2, Windows 10 October 2020 Update
readonly BN_MAY_TWNETONE=19043		#21H1, Windows 10 May 2021 Update
readonly BN_NOV_TWENTONE=19044		#21H2, Windows 10 November 2021 Update
# Windows 11
readonly BN_ELEVEN_21H2=22000		#21H2, Windows 11

# echo functions
function debug_echo {
  [ "$wslu_debug" == "--debug" ] && echo "${orange}${bold}[debug:${wslu_util_fullpath}]${reset} $*" 1>&2;
}

function error_echo {
  echo "${error} $1"
  exit "$2"
}

# Check if the version number of bash is greater or equal to 4.4
if [ "$bash_version_major" -lt 4 ] || { [ "$bash_version_major" -eq 4 ] && [ "$bash_version_minor" -lt 4 ]; }; then
  error_echo "Bash version is too old. Please upgrade to 4.4 or later." 1
fi


# source default config
if [ -f "${wslu_dest_dir}${wslu_prefix}/share/wslu/conf" ]; then
  debug_echo "source default setting"
  source "${wslu_dest_dir}${wslu_prefix}/share/wslu/conf"
fi

# source user-defined config
if [ -f "${wslu_dest_dir}${wslu_prefix}/share/wslu/custom.conf" ]; then
  debug_echo "${wslu_dest_dir}${wslu_prefix}/share/wslu/custom.conf found, sourcing"
  source "${wslu_dest_dir}${wslu_prefix}/share/wslu/custom.conf"
fi

if [ -f "${wslu_dest_dir}/etc/wslu/conf" ]; then
  debug_echo "${wslu_dest_dir}/etc/wslu/conf found, sourcing"
  source "${wslu_dest_dir}/etc/wslu/conf"
fi

if [ -f "/etc/wslu/custom.conf" ]; then
  debug_echo "/etc/wslu/custom.conf found, sourcing"
  source "/etc/wslu/custom.conf"
fi

if [ -f "$HOME/.config/wslu/conf" ]; then
  debug_echo "$HOME/.config/wslu/conf found, sourcing"
  source "$HOME/.config/wslu/conf"
fi
if [ -f "$HOME/.wslurc" ]; then
  debug_echo "$HOME/.wslurc found, sourcing"
  source "$HOME/.wslurc"
fi

# functions

function help {
  app_name=$wslu_util_name
  echo -e "$app_name - Part of wslu, a collection of utilities for Windows Subsystem for Linux (WSL)
Usage: $2

For more help for $app_name, please use the command \`man $app_name\` or visit the following site: https://wslutiliti.es/wslu/man/$app_name.html.
For overall help, you can use the command \`man wslu\` or visite the following site: https://wslutiliti.es/wslu."
}

function version {
  echo "wslu v$wslu_version"
}

function double_dash_p {
  echo "${@//\\/\\\\}"
}

function interop_prefix {

  win_location="/mnt/"
  tmp="$(__wsl_conf_read automount root)"
  [ "$tmp" == "" ] || win_location="$tmp"
  [[ "$win_location" =~ ^.*/$ ]] || win_location="$win_location/" # make sure it always end with slash
  unset tmp
  echo "$win_location"

  unset win_location
}

function sysdrive_prefix {
  hard_reset=0
  for pt in "$(interop_prefix)"/*; do
    [[ -e "$pt" ]] || break
    if [ "$(echo "$pt" | wc -l)" -eq 1 ]; then
      if [ -d "$pt/Windows/System32" ]; then
        hard_reset=1
        pt=${pt%/}
        win_location="${pt##*/}"
        break
      fi
    fi
  done

  if [ $hard_reset -eq 0 ]; then
    win_location="c"
  fi

  echo "$win_location"

  unset win_location
  unset hard_reset
}

function wslu_get_build {
  build=$("$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/reg.exe query "HKLM\\Software\\Microsoft\\Windows NT\\CurrentVersion" /v CurrentBuild | tail -n 2 | head -n 1 | sed -e 's|\r||g')
  echo "${build##* }"
}

function wslu_get_wsl_ver {
  wslutmpbuild="$(( $(wslu_get_build) + 0 ))"
  if [ $wslutmpbuild -ge $BN_MAY_NINETEEN ]; then
    # The environment variable only available in 19H1 or later.
    wslu_distro_regpath=$("$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/reg.exe query "HKCU\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Lxss" /s /f DistributionName 2>&1 | sed -e 's|\r||g' | grep -B1 -e "$WSL_DISTRO_NAME$" | head -n1 )
    if "$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/reg.exe query "$wslu_distro_regpath" /v Flags &>/dev/null; then
      wslu_distro_version=$("$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/reg.exe query "$wslu_distro_regpath" /v Flags | tail -n 2 | head -n 1 | sed -e 's|\r||g')
      wslu_distro_version=${wslu_distro_version##* }
      wslu_distro_version_processed=$(( "$(printf "%d\n" "$wslu_distro_version")" / 8 ))
      if [ "$wslu_distro_version_processed" == "1" ]; then
        echo "2"
      elif [ "$wslu_distro_version_processed" == "0" ]; then
        echo "1"
      fi
    else
      echo "1"
    fi
  else
    echo "1"
  fi
}

function chcp_com {
  "$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/chcp.com "$@" >/dev/null
}

function winps_exec {
  debug_echo "winps_exec: called with command $*"
  if [[ "$WSLU_POWERSHELL_CHCP_WORKAROUND" == "true" ]]; then
    wslutmpbuild="$(wslu_get_build)"
    local cp
    cp="$(cat "${wslu_state_dir}"/oemcp 2>/dev/null)"
    if [[ -z "$cp" ]]; then
      var_gen
      cp="$(cat "${wslu_state_dir}"/oemcp 2>/dev/null)"
    fi

    [ "$wslutmpbuild" -ge "$BN_OCT_NINETEEN" ] || chcp_com "$cp"
    "$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/WindowsPowerShell/v1.0/powershell.exe -NoProfile -NonInteractive -ExecutionPolicy Bypass -Command "[Console]::OutputEncoding = [System.Text.Encoding]::UTF8; [Console]::InputEncoding = [System.Text.Encoding]::GetEncoding($cp); $*"
    EXIT_STATUS=$?
    [ "$wslutmpbuild" -ge "$BN_OCT_NINETEEN" ] || chcp_com 65001
    return "$EXIT_STATUS"
  else
    "$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/WindowsPowerShell/v1.0/powershell.exe -NoProfile -NonInteractive -ExecutionPolicy Bypass -Command "$*"
    EXIT_STATUS=$?
    return "$EXIT_STATUS"
  fi
}

function cmd_exec {
  debug_echo "cmd_exec: called with command $*"
  "$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/cmd.exe /c "$@"
  EXIT_STATUS=$?
  return $EXIT_STATUS
}

function baseexec_gen {
  debug_echo "baseexec_gen: called"
  wslutmpbuild="$(( $(wslu_get_build) + 0 ))"
  debug_echo "baseexec_gen: winbuild: $wslutmpbuild"
  if [ $wslutmpbuild -ge $BN_MAY_NINETEEN ]; then
    # The environment variable only available in 19H1 or later.
    debug_echo "baseexec_gen: 19H1 or higher"
    wslu_distro_regpath=$("$(interop_prefix)"c/Windows/System32/reg.exe query "HKCU\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Lxss" /s /f DistributionName 2>&1 | sed -e 's|\r||g' | grep -B1 -e "$WSL_DISTRO_NAME$" | head -n1 )
    if "$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/reg.exe query "$wslu_distro_regpath" /v PackageFamilyName &>/dev/null; then
      wslu_distro_packagename=$("$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/reg.exe query "$wslu_distro_regpath" /v PackageFamilyName | tail -n 2 | head -n 1 | sed -e 's|\r||g')
      # if it is a store distro
      debug_echo "baseexec_gen: store distro: $wslu_distro_packagename"
      wslu_distro_packagename=${wslu_distro_packagename##* }
      wslu_base_exec_folder_path="$(wslpath "$(winps_exec "[Environment]::GetFolderPath('LocalApplicationData')" | tr -d "\r")\\Microsoft\\WindowsApps\\$wslu_distro_packagename")"
      debug_echo "baseexec_gen: base_exe_folder_path: $wslu_base_exec_folder_path"
      if find "$wslu_base_exec_folder_path" -name "*.exe" -print -quit &>/dev/null; then
        debug_echo "baseexec_gen: found exe in wslu_base_exec_folder_path"
        wslpath -w "$(find "$wslu_base_exec_folder_path" -name "*.exe" -print -quit)" > "${wslu_state_dir}"/baseexec
      else
        debug_echo "baseexec_gen: do not have base exec in the folder; use fallback"
        echo "$(wslpath -w "$(interop_prefix)$(sysdrive_prefix)")\\Windows\\System32\\wsl.exe" > "${wslu_state_dir}"/baseexec
      fi
    else
      debug_echo "baseexec_gen: imported distro"
      # if it is imported distro
      echo "$(wslpath -w "$(interop_prefix)$(sysdrive_prefix)")Windows\\System32\\wsl.exe" > "${wslu_state_dir}"/baseexec
    fi
  else
    debug_echo "baseexec_gen: fallback mode"
    # older version fallback.
    echo "$(wslpath -w "$(interop_prefix)$(sysdrive_prefix)")\\Windows\\System32\\wsl.exe" > "${wslu_state_dir}"/baseexec
  fi
}

function var_gen {
  debug_echo "var_gen: called"
  date +"%s" > "${wslu_state_dir}"/triggered_time

  rm -f "${wslu_state_dir}"/baseexec
  rm -f "${wslu_state_dir}"/oemcp

  # generate oem codepage
  "$(interop_prefix)$(sysdrive_prefix)"/Windows/System32/reg.exe query "HKLM\\SYSTEM\\CurrentControlSet\\Control\\Nls\\CodePage" /v OEMCP 2>&1 | sed -n 3p | sed -e 's|\r||g' | grep -o '[[:digit:]]*' > "${wslu_state_dir}"/oemcp
  # generate base exe location
  baseexec_gen

}

function wslu_function_check {
  # from https://stackoverflow.com/questions/85880/determine-if-a-function-exists-in-bash
  debug_echo "wslu_function_check: called with $*"
  declare -f -F "$1" > /dev/null
  return $?
}

function wslu_file_check {
  debug_echo "wslu_file_check: called with $*"
  should_i_show=""
  [[ "$3" == "?!S" ]] && should_i_show="n"

  if [[ ! -f "$1/$2" ]]; then
    [[ -z "$should_i_show" ]] && echo "${warn} $2 not found in Windows directory. Copying right now..."
    [[ -d "$1" ]] || mkdir "$1"
    if [[ -f "/usr/share/wslu/$2" ]]; then
      cp "/usr/share/wslu/$2" "$1"
      [[ -z "$should_i_show" ]] && echo "${info} $2 copied. Located at \"$1\"."
    else
      [[ -z "$should_i_show" ]] && echo "${error} $2 not found. Failed to copy."
      exit 30
    fi
  fi
}

function wslpy_check {
  debug_echo "wslpy_check"
  if type python3 > /dev/null 2>&1; then
    debug_echo "wslpy_check: python3 installed."
    tmp_wslpy_ver="$(python3 -c "import wslpy; print(wslpy.__version__)" 2>/dev/null)"
    if [[ "$tmp_wslpy_ver" != "" ]]; then
      debug_echo "wslpy_check: wslpy installed."
      older_ver="$(echo -e "$tmp_wslpy_ver\n0.1.0" | sort -n -t. | head -n1)"
      if [[ "$older_ver" == "$tmp_wslpy_ver" ]]; then
        debug_echo "wslpy_check: wslpy installed but a version < 0.1.0 is installed."
        return 1
      else
        debug_echo "wslpy_check: wslpy >= 0.1.0 is installed."
        return
      fi
    else
      debug_echo "wslpy_check: wslpy not installed."
      return 1
    fi
  else
    debug_echo "wslpy_check: python3 not installed."
    return 1
  fi
}


# pre_check to make sure WSL_INTEROP is properly set in WSL2
if [ "$(wslu_get_wsl_ver)" == "2" ] && [ -z "$WSL_INTEROP" ]; then
  for i in $(pstree -np -s $$ | grep -o -E '[0-9]+'); do
    if [[ -e "/run/WSL/${i}_interop" ]]; then
      export WSL_INTEROP=/run/WSL/${i}_interop
    fi
  done
fi

# first run, saving some information
if [ ! -d ~/.config/wslu ]; then
  debug_echo "first run; creating ~/.config/wslu"
  mkdir -p ~/.config/wslu
fi

# This gets tirggered then:
# 1. if it's the first time the script is triggered, i.e.,
#    ${wslu_state_dir}/triggered time
# 2. if update_time is also not present, i.e.,
#    badly installed packages or installed via install script
if [ ! -f "${wslu_state_dir}"/triggered_time ] || [ ! -f /usr/share/wslu/updated_time ]; then
  debug_echo "first run or update_time not present; calling var_gen"
  var_gen
# This gets triggered when:
#    installed time is larger than the last triggered time
elif [ "$(cat "${wslu_state_dir}"/triggered_time)" -lt "$(cat /usr/share/wslu/updated_time)" ]; then
  debug_echo "upgraded package; calling var_gen"
  var_gen
fi

# basic distro detection
distro="$(sed -n -e '/^NAME=.*/p' /etc/os-release | sed -e 's/^NAME=\"//g')"
case $distro in
  *Clear\ Linux*) distro="clear";;
  *Common\ Base\ Linux\ Mariner*) distro="cblm";;
  *Pengwin*) distro="pengwin";;
  *WLinux*) distro="wlinux";;
  Ubuntu*) distro="ubuntu";;
  *Debian*) distro="debian";;
  *Kali*) distro="kali";;
  openSUSE*) distro="opensuse";;
  SLES*) distro="sles";;
  Alpine*) distro="alpine";;
  Arch*) distro="archlinux";;
  *Oracle*) distro="oracle";;
  AlmaLinux*) distro="almalinux";;
  Scientific*) distro="scilinux";;
  *Fedora\ Remix\ for\ WSL*) distro="fedoraremix";;
  *Fedora*) distro="fedora";;
  *Gentoo*) distro="gentoo";;
  *Generic*) [ "fedora" == "$(grep -e "LIKE=" /etc/os-release | sed -e 's/ID_LIKE=//g')" ] && distro="oldfedora" || distro="unknown";;
  *) distro="unknown";;
esac

debug_echo "distro: $distro"
# shellcheck shell=bash
##########   CAUTION   ###########
## wslupath is a legacy cli for backward compatbility.
## Use it unless it is necessary.

style=1
reg_path=0
set_path=""

help_short="wslupath [-dOr] [-D|-A|-T|-S|-W|-s|-su|-H|-P|...NAME...]\nwslupath [-h|-v|-R]"

function path_double_dash {
	new_path="${*//\\/\\\\}"
	echo "$new_path"
}

function general_converter {
	target="$*"

	if [[ $target =~ ^[A-Z]:(\\[^:\\]+)*(\\)?$ ]]; then
		p=$(wslpath -u "${target}")
	elif [[ $target =~ ^$(interop_prefix)[A-Za-z](/[^/]+)*(/)?$ ]]; then
		p=$(wslpath -w "${target}")
	else
		echo "${error} No proper path form detected: ""$*""."
		exit 20
	fi
	echo "$p"
}

function style_path {
	case $style in
		1) p="$(general_converter "$@")";;
		2) p="$*";;
		3) p="$(path_double_dash "$@")";;
	esac
	echo "$p"
}

if [[ $# -eq 0 ]]; then
	echo -e "$help_short"
	exit 20
else
	for args; do
		case $args in
			#styles
			-r|--reg-data) reg_path=1;;
			-O|--original) style=2;;
			-d|--doubledash-dir) style=3;;
			## system location

			-D|--desktop)
			set_path="$(style_path "$(wslvar -l 'Desktop')")"
			break;;
			-A|--appdata)
			set_path="$(style_path "$(wslvar -s APPDATA)")"
			break;;
			-T|--temp)
			set_path="$(style_path "$(wslvar -s TMP)")"
			break;;
			-S|--sysdir)
			set_path="$(style_path "$(wslvar -s windir)"\\System32)"
			break;;
			-W|--windir)
			set_path="$(style_path "$(wslvar -s windir)")"
			break;;
			-s|--start-menu)
			set_path="$(style_path "$(wslvar -l 'Start Menu')")"
			break;;
			-su|--startup)
			set_path="$(style_path "$(wslvar -l 'Startup')")"
			break;;
			-H|--home)
			set_path="$(style_path "$(wslvar HOMEDRIVE)""$(wslvar HOMEPATH)")"
			break;;
			-P|--program-files)
			set_path="$(style_path "$(wslvar -s ProgramFiles)")"
			break;;
			-h|--help) help "$0" "$help_short"; exit;;
			-v|--version) version; exit;;
			-R|--avail-reg) echo "Available registery input:"
			wslvar -L
			exit;;
			*)
			if [[ "$reg_path" == "1" ]]; then
				set_path="$(style_path "$(wslvar -l "$args")")"
			else
				set_path="$(style_path "$args")"
			fi
			break;;
		esac
	done
fi

if [[ "$set_path" == "" ]]; then
	echo "${error}No path input. Aborted."
	exit 21
else
	echo "$set_path"
fi
