#!/bin/ksh
#
# CD Player frontend for CDDA2WAV
#
# Programmed during the rainy feb 12, 2005
# (c) Peter van Eerten - free for all use
#
# Runs with GTK-server 2.2.1 or higher.
#
# 1.0: Initial release
# 1.1: Fixes for CDDA2WAV on OpenBSD (june 1 2005)
# 1.2: Now combobox synchronizes with track (june 4 2005)
# 1.2a: Fixes for CD's with more than 10 tracks (september 9, 2005)
# 1.3:	-Removed ' character from titles (october 18, 2005)
#	-Support for intern. characters (october 18, 2005)
# 1.4:	-Revised for async event handling (june 18, 2006)
#	-Window does not resize when track titles have large size (june 18, 2006)
# 1.5:	-Major code improvements (july 22, 2008)
#-------------------------------------------------------------------------------------
#
# Minimalistic frontend to play audio CD's over PCM
#
# Required tools:
# -cdda2wav
# -GNU Awk
# -rexima OR aumix
# -...and of course coreutils like 'cat' and 'tr'.
#
#------------------------------------------------ CHECK

function Check_Software
{
# Check on availability of AWK
AWK=`which gawk 2>/dev/null`
if [[ -z $AWK ]]
then
    echo "GNU Awk not found on your system! Exiting..."
    exit 1
fi

# Check on availability of REXIMA or AUMIX
MIXER=`which rexima 2>/dev/null`
if [[ -z $MIXER || $MIXER = "rexima: Command not found." ]]
then
    MIXER=`which aumix 2>/dev/null`
    if [[ -z $MIXER || $MIXER = "aumix: Command not found." ]]
    then
	echo "No mixer found! Exiting..."
	exit 1
    fi
fi

# Check on availability of cdda2wav
CDDA2WAV=`which cdda2wav 2>/dev/null`
if [[ -z $CDDA2WAV ]]
then
    echo "cdda2wav not found on your system! Exiting..."
    exit 1
fi
}

CDPARANOIA=`which cdparanoia >/dev/null`

#------------------------------------------------ GTK

# Communication function; $1 contains the string to be send
function gtk
{
print -p $1
read -p RESULT
}

#------------------------------------------------ GUI

function Build_Gui
{
# Start GTK-server in STDIN mode
gtk-server -stdin |&

# Check GTK version
gtk "gtk_check_version 2 4 0"
if [[ -n $RESULT ]]
then
    echo "Your GTK installation is too old!"
    echo "GTK version 2.4.0 or higher is required. Exiting..."
    gtk "gtk_server_exit"
    exit 1
fi

# Define GUI - mainwindow
gtk "gtk_init NULL NULL"
gtk "gtk_window_new 0"
WINDOW=$RESULT
gtk "gtk_window_set_title $WINDOW 'CD Player 1.5'"
gtk "gtk_window_set_position $WINDOW 1"
#gtk "gtk_widget_set_size_request $WINDOW 350 60"
# Register timeout in WAIT callback later
gtk "gtk_server_connect $WINDOW show main_window"
gtk "gtk_server_timeout 500 $WINDOW show"
# Buttons
gtk "gtk_button_new_from_stock gtk-stop"
G_BUTTON_STOP=$RESULT
gtk "gtk_button_new_from_stock gtk-refresh"
G_BUTTON_REFRESH=$RESULT
gtk "gtk_button_new_from_stock gtk-quit"
G_BUTTON_QUIT=$RESULT
gtk "gtk_button_new_from_stock gtk-help"
G_BUTTON_HELP=$RESULT
# Volume slider
gtk "gtk_vscale_new_with_range 0 100 1"
G_VOLUME=$RESULT
gtk "gtk_scale_set_draw_value $G_VOLUME 0"
gtk "gtk_range_set_value $G_VOLUME 25"
# Combobox with titles of CD
gtk "gtk_combo_box_new_text"
G_COMBO=$RESULT
# Create layout
gtk "gtk_hbox_new 0 0"
H1BOX=$RESULT
gtk "gtk_box_pack_start $H1BOX $G_BUTTON_STOP 1 1 1"
gtk "gtk_box_pack_start $H1BOX $G_BUTTON_REFRESH 1 1 1"
gtk "gtk_box_pack_start $H1BOX $G_BUTTON_HELP 1 1 1"
gtk "gtk_box_pack_end $H1BOX $G_BUTTON_QUIT 1 1 1"
gtk "gtk_vbox_new 0 0"
VBOX=$RESULT
gtk "gtk_box_pack_start $VBOX $H1BOX 1 1 1"
gtk "gtk_box_pack_start $VBOX $G_COMBO 1 1 1"
gtk "gtk_hbox_new 0 0"
HTOPBOX=$RESULT
gtk "gtk_box_pack_start $HTOPBOX $VBOX 1 1 1"
gtk "gtk_box_pack_start $HTOPBOX $G_VOLUME 0 0 0"
gtk "gtk_container_add $WINDOW $HTOPBOX"
gtk "gtk_widget_show_all $WINDOW"
# Create ABOUT box
gtk "gtk_server_version"
TMP="\t*** A simple CD player for XFCE ***\r\rProgrammed with KSH and GTK-server $RESULT.\r\r Visit http://www.gtk-server.org/ for more info!"
gtk "gtk_message_dialog_new $WINDOW 0 0 2 '$TMP' ''"
ABOUT=$RESULT
gtk "gtk_window_set_title $ABOUT 'About CD Player 1.5'"
}

#------------------------------------------------ CDLOOKUP

function Lookup_CD
{
# Kill existing playing process first
Stop_CD

# First remove existing tracks from widget
if [[ $TRACKS -gt 0 ]]
then
    COUNTER=0
    until [[ $COUNTER -eq $TRACKS ]]
    do
	gtk "gtk_combo_box_remove_text $G_COMBO 0"
	((COUNTER+=1))
    done
fi

# Check availability of CD
if [[ -n $CDPARANOIA ]]
then
    CHECK=`$CDPARANOIA -Q 2>&1`
    if [[ $CHECK = +(*004*) ]]
    then
	return
    fi
fi

# Lookup information from CDDB
$CDDA2WAV -D $CDROM -J -v titles -L 1 -N -H 2>&1 | tr -d "'" | $AWK '/Album/ {print} /Track/ {print}' > $CDFILE

# Determine amount of tracks (includes album title)
TRACKS=`$AWK 'BEGIN {t = 0} /Track/ {t+=1} END {print t}' $CDFILE`

# If no tracks then reread CD
if [[ $TRACKS -lt 1 ]]
then
    # Restore default title
    gtk "gtk_window_set_title $WINDOW 'Unknown album'"
    # Get physical track index
    $CDDA2WAV -D $CDROM -J -v toc -N -H -g 2>&1 | tr -d "'" > $CDFILE
    # Determine amount of tracks (includes album title)
    TRACKS=`$AWK 'BEGIN {t = 0} /T[0-9]/ {t+=1} END {print t}' $CDFILE`
    # Add track numbering to combobox
    COUNTER=1
    until [[ $COUNTER -gt $TRACKS ]]
    do
	gtk "gtk_combo_box_append_text $G_COMBO '$COUNTER - Unknown track'"
	((COUNTER+=1))
    done
else
    # Add CD title to window title 
    L_TITLE=`$AWK '/Album/ {print}' $CDFILE`
    gtk "gtk_window_set_title $WINDOW '$L_TITLE'"
    # Add tracks to combobox
    COUNTER=1
    while read LINE
    do
	if [[ $LINE == +(*Track*) ]]
	then
	    gtk "g_locale_to_utf8 '$LINE' -1 NULL NULL NULL"
	    gtk "gtk_combo_box_append_text $G_COMBO '$RESULT'"
	fi
    done < $CDFILE
fi
}

#------------------------------------------------ STOP

function Stop_CD
{
# Only if PID exists, kill process
if [[ -n $P_PID ]]
then
    STOPPED=1
    kill -9 $P_PID >/dev/null 2>&1
    P_PID=""
fi
}

#------------------------------------------------ PLAY

function Play_CD
{
# Get selected track from combo
gtk "gtk_combo_box_get_active $G_COMBO"
let P_TRACK=$RESULT+1

# Kill existing playing process first
Stop_CD

# Start playing and save PID
$CDDA2WAV -D $CDROM -q -e -t$P_TRACK -d0 -N >/dev/null 2>&1 &

# Unset stopped flag
STOPPED=0

# Save ProcessID
P_PID=`jobs -p | head -1`
}

#------------------------------------------------ SELECT NEXT TRACK

function Action_Track
{
# Find out if track currently is being played
TMP=`jobs -l | grep $P_PID 2>/dev/null`

# If not, and not stopped, goto next track
if [[ -z $TMP && $STOPPED -eq 0 ]]
then
    # Get selected track from combo
    gtk "gtk_combo_box_get_active $G_COMBO"
    let P_TRACK=$RESULT+1

    # Put to next track
    if [[ $P_TRACK -lt $TRACKS ]]
    then
	# Put combobox to next track, inducing signal
	gtk "gtk_combo_box_set_active $G_COMBO $P_TRACK"
    fi
fi
}

#------------------------------------------------ VOLUME

function Adjust_Volume
{
# Get current value
gtk "gtk_range_get_value $G_VOLUME"
let V_VOL=100-`$AWK -v VAR=$RESULT 'BEGIN {print int(VAR)}'`

case $MIXER in
    `which rexima 2>/dev/null`) $MIXER pcm $V_VOL;;
    `which aumix 2>/dev/null`) $MIXER -v $V_VOL;;
esac
}

#------------------------------------------------ MAIN

# Set global variables
CDROM=/dev/cdrom
CDFILE=/tmp/CD.txt

# Check available packages
Check_Software

# Create GUI
Build_Gui

# Get CD info
Lookup_CD

# Put volume to default
Adjust_Volume

# Initialize variables
EVENT=0

# Mainloop
while [[ $EVENT -ne $WINDOW && $EVENT -ne $G_BUTTON_QUIT ]]
do
    # Wait for event
    gtk "gtk_server_callback wait"
    EVENT=$RESULT

    # Check events
    case $EVENT in

	# If refresh button is pressed
	$G_BUTTON_REFRESH)
	    Lookup_CD;;

	# If help button is pressed
	$G_BUTTON_HELP)
	    gtk "gtk_widget_show $ABOUT";;

	# If OK button in HELP dialog is pressed
	$ABOUT)
	    gtk "gtk_widget_hide $ABOUT";;

	# If stop button is pressed
	$G_BUTTON_STOP)
	    Stop_CD;;

	# If volume slider is moved
	$G_VOLUME)
	    Adjust_Volume;;

	# If combobox is changed
	$G_COMBO)
	    Play_CD;;
    esac

    # Check if we need to go to next track
    Action_Track

done

# Before exiting, stop playing CD
Stop_CD

# Remove temporary file
rm -f $CDFILE

# Exit GTK
gtk "gtk_server_exit"