Simple script to play a WAV notification sound

play_sound_notification.sh

#!/bin/bash
# Play notification sound at givel volume with given file

PATH_TO_NOTIFICATIONS="/home/USER/Music/notifications"
PATH_TO_DING="/home/USER/Music/notifications/stop.wav"

verbose=$3
sound_volume=$1
file_to_play=$2

play_sound_notification(){
  # No verbose by default, and verbose if any arg!
  if [ -z "$verbose" ]; then
    verbose=false
  else
    verbose=true
    echo "DEBUG: mode at any arg: $verbose"
  fi

  # Volume check if integer:
  if [[ "$sound_volume" =~ ^[0-9]+$ || "$sound_volume" =~ ^[-][0-9]+$  ]]; then
    # Volume check if GTE 101 or LT 1:
    if [[ $sound_volume -ge 101 ]] || [[ $sound_volume -lt 0 ]]; then
      echo "ERROR: Volume is incorrect not 1-100: $volume"
      return 0
    fi
    # All correct:
    if $verbose ; then echo "DEBUG: volume is OK: $volume"; fi
  else
    echo "ERROR: Volume is incorrect, not an integer: $volume"
    return 0
  fi

  # Check if file exsists:
  file_full_path="$PATH_TO_NOTIFICATIONS/$file_to_play"
  if [ -f $file_full_path ]; then
      if $verbose ; then echo echo "DEBUG: file exists: $file_full_path"; fi
  else
    echo "File: $file_to_play"
    echo "ERROR: The file does not exist at path with this name: $file_full_path"
    return 0
  fi

  # Set volume:
  if $verbose; then
    echo "Set volume at level: $sound_volume"
    echo "============================"
    amixer set Master $sound_volume%
    echo "============================"
    echo "Play initial ding to wake up USB Sound device: $PATH_TO_DING"
    aplay --device="dmix:CARD=Audio,DEV=0" -q --nonblock --duration=1 $PATH_TO_DING
    echo "Now play requested notification: $file_full_path"
    aplay --device="dmix:CARD=Audio,DEV=0" -q $file_full_path
    echo "Set volume back at level 10%"
    echo "============================"
    amixer set Master 10%
    echo "============================"
  else
    amixer set Master $sound_volume% >> /dev/null
    aplay --device="dmix:CARD=Audio,DEV=0" -q --nonblock --duration=1 $PATH_TO_DING
    aplay --device="dmix:CARD=Audio,DEV=0" -q $file_full_path
    amixer set Master 10% >> /dev/null
  fi
  # Play notification:

  # End and exit
  return 0
}

play_sound_notification $sound_volume $file_to_play $verbose