#!/bin/bash

VERSION="1.4"

# ---------- configuration -----------#
# For ex. 1.2 and 10 are suitable values for the mouse
MOUSE_DECELERATION=1.2 # don't set below 1.0 !!!
MOUSE_SCALING=10

# Most touchpads contain the string "touchpad" (this is case insensitive)
TOUCHPAD_STRING="touchpad"
#For ex. 3.0 and 10 are suitable values for the touchpad.
TOUCHPAD_DECELERATION=3.0 # don't set below 1.0 !!!
TOUCHPAD_SCALING=10

# -------- end of configuration -------#

# -------- auto-detect mouse -------#
# select all slave pointers that are not the Virtual core pointer, 
# nor a touchscreen, nor the touchpad:
MOUSE=$(xinput --list --short | grep "slave  pointer" | egrep -iv "Virtual core|touchscreen" | grep -v "Virtual core" | grep -iv "$TOUCHPAD_STRING" | cut -f 1 | cut -d" " -f 5- | sed 's/\s\+$//g')
#edit this section if needed:
#MOUSE="YOUR-MOUSE-IDENTIFIER"

#--------- installation --------------#
# In case you use a touchpad without the string "touchpad" in it's identifier string adapt the 
# variable TOUCHPAD_STRING in the configuration section
# search for the right string with
# xinput --list --short

#-------------- Author:  -------------#
# by Ruben Barkow
# Website: 	http://coffeeplusplus.z11.de
# 		An ergonomic alternative keyboard-layout for typing with both hands and optional with only one (english and german)
# git: 		https://github.com/rubo77/mouse-speed

#--- Copyright and license -----------#
#This code is covered by the GNU General Public License 3.


# state-file where the current speed is saved:
CURRENTSPEEDFILE=/tmp/.mouse-speed.state
# initial percent of speed:
CURRENTSPEED=100

#############

store_speed ()
{
	echo "CurrenSpeed: $CURRENTSPEED" >$CURRENTSPEEDFILE
	echo "# this is the current speed-state for mouse-speed" >>$CURRENTSPEEDFILE
}

#store and read configfile:
if [ -f $CURRENTSPEEDFILE ] ; then
	CURRENTSPEED=$(cat $CURRENTSPEEDFILE | grep CurrenSpeed:| cut -d ' ' -f 2 )
else
	echo "Initiate mouse-speed"
	echo "create state file in $CURRENTSPEEDFILE"
	store_speed
	chmod 777 $CURRENTSPEEDFILE
fi
VERBOSE=false

# Execute getopt on the arguments passed to this program, identified by the special character $@
PARSED_OPTIONS=$(getopt -n "$0"  -o hrs:vVd:a: --long "help,reset,set:,verbose,vv,version,decelerate:,accelerate:"  -- "$@")

#Bad arguments, something has gone wrong with the getopt command.
if [ $? -ne 0 ]; then
  exit 1
fi

# A little magic, necessary when using getopt.
eval set -- "$PARSED_OPTIONS"

# Now go through all options with a case and using shift to analyse one argument at a time.
# $1 identifies the first argument, and when we use shift we discard the first argument, 
# so $2 becomes $1 and goes again through the case.
while true; do
  case "$1" in

    -h|--help)
      echo "

  NAME:

    mouse-speed

  DESCRIPTION:

    this script sets the mouse- and touchpad accelleration speed 
    to a relative percentage of the previous speed or to a certain absolute percentage

  GLOBAL OPTIONS:
    
    Mandatory arguments to long options are mandatory for short options too.
    
    -d, --decelerate=PERCENT
        decellerate for PERCENT of previous value
    -a, --accelerate=PERCENT
        accellerate for PERCENT of previous value
    -s, --set=PERCENT
        set the speed to PERCENT
    -r, --reset
        Reset to 100% (the same as mouse-speed -s 100)
    -h, --help 
        Display help documentation
    -V, --version 
        Display version information
    -v, --verbose
        more verbose output
    --vv
        even more verbose (for debugging onny)
   
  USAGE EXAMPLES:
      
    # decellerate the mouse for 50%:
    mouse-speed -d 50

    # accelerate the mouse for 50%:
    mouse-speed -a 50

    # reset mouse speed to 100%:
    mouse-speed -r 

    # set mouse speed to 30%:
    mouse-speed -s 30
    
  DEVELOPER INFO
  
    requires the package xinput
    
    In case your mouse or touchpad are not recognized, adapt this script
    to the right mouse and touchpad devices with the help of the command:
    $ xinput --list --short
    add the right names for your devices in the configuration section of
    this script
    
    This procect on git:        https://github.com/rubo77/mouse-speed
"
      exit
      shift;;

    -V|--version)
      echo "mouse-speed $VERSION"
      exit 
      shift;;
    
    -r|--reset)
      echo "Speed reset to 100%"
      let CURRENTSPEED=100
      shift;;

    -d|--decelerate)
      #decelerate speed if argument -d i set
      if [ -n "$2" ]; then
        echo "Speed decellerated for $2"
        let CURRENTSPEED=$(($CURRENTSPEED * $((100-$2)) /100))
      fi
      shift 2;;

    -a|--accelerate)
      if [ -n "$2" ]; then
        echo "Speed accellerated for $2"
        let CURRENTSPEED=$(($CURRENTSPEED * $((100+$2)) /100))
        if [ $CURRENTSPEED -lt 3 ]; then
          CURRENTSPEED=$(($CURRENTSPEED+1))
        fi
      fi
      shift 2;;

    -s|--set)
      if [ -n "$2" ]; then
        echo "Speed set to $2%"
        let CURRENTSPEED=$2
      else
        echo "Missing argument at option $2"
      fi
      shift 2;;

    -v|--verbose)
      VERBOSE=true
      # for the verbose output:
      PS4="executing: "
      shift;;

    --vv)
      # very verbose for debugging
      VERBOSE=true
      set -x
      shift;;

    --)
      shift
      break;;
  esac
done


if [[ $CURRENTSPEED -gt 100 ]]; then 
    echo "SPEED max is 100%"
    CURRENTSPEED=100
fi
if [[ $CURRENTSPEED -lt 1 ]]; then 
    echo "SPEED min is 1%"
    CURRENTSPEED=1
fi

store_speed
echo new Speed: $CURRENTSPEED

MOUSE_DECELERATION=$(bc <<< "scale = 1; $MOUSE_DECELERATION * 100 / $CURRENTSPEED")
echo new mouse deceleration: $MOUSE_DECELERATION; 
TOUCHPAD_DECELERATION=$(bc <<< "scale = 1; $TOUCHPAD_DECELERATION * 100 / $CURRENTSPEED")
echo new touchpad deceleration: $TOUCHPAD_DECELERATION; 
        
#set touchpad
TP=$(xinput --list --short | grep -i $TOUCHPAD_STRING | cut -f 1 | cut -d" " -f 5- | sed 's/\s\+$//g')
if [ "$TP" ]; then
  if [ $VERBOSE == true ]; then
    echo setting speed for $TP
    echo was before:
    xinput --list-props "$TP"|grep Accel
  fi
  ( $VERBOSE && set -x
  xinput --set-prop "$TP" "Device Accel Constant Deceleration" $TOUCHPAD_DECELERATION
  xinput --set-prop "$TP" "Device Accel Velocity Scaling" $TOUCHPAD_SCALING
  )
  if [ $VERBOSE == true ]; then
    echo touchpad now set to:
    xinput --list-props "$TP"|grep Accel
  fi
elif [ $VERBOSE == true ]; then
  echo 'Touchpad device "'$TOUCHPAD_STRING'" not in xinput --list'
  echo call '"'$0 -help'"' for help
  echo
fi

#set mouse
if [ "$MOUSE" ]; then
 echo "$MOUSE"|while read -r M; do
  echo setting mouse-speed for '"'$M'"'
  ( $VERBOSE && set -x
  xinput --set-prop "pointer:$M" "Device Accel Constant Deceleration" $MOUSE_DECELERATION
  xinput --set-prop "pointer:$M" "Device Accel Velocity Scaling" $MOUSE_SCALING
  )
  if [ $VERBOSE == true ]; then
    echo mouse now set to:
    xinput --list-props "$M"|grep Accel
  fi
 done
elif [ $VERBOSE == true ]; then
  echo 'Mouse device not found in xinput --list'
  echo "If you have a mouse installed that wasn't found,"
  echo "call "'"'$0 --help'"'" for help"
fi

exit 0