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#! /usr/bin/perl
#########################################################################
#        This Perl script is Copyright (c) 2006, Peter J Billam         #
#     c/o P J B Computing, GPO Box 669, Hobart TAS 7001, Australia      #
#                                                                       #
#     This script is free software; you can redistribute it and/or      #
#            modify it under the same terms as Perl itself.             #
#########################################################################
# see 20111002    midislide ?
# 20140306 seconded ! : for pitch-adjusting the midi
#   when there are midi files and audio-files
#   so that the synth can be tuned by hand to an arbitrary wav file
# could simply offer pitchbend as a alternative to cc=?
#   perhaps just the letter "p" instead of the cc number !
# Or, should always apply to all channels ? This will be the common case...
#
# Also: an audiofile-mixer option, which starts up a suitable ecasound
# and offers vol,pan,filter on each audiofile !
#   midifade -audio v,p gtr.wav v,f,q str.wav v brass.wav backing.wav

# and could record its fadermovements in a midi file
#   which (or several of which) can be replayed behind subsequent passes
#   should contain a comment on which vpfq and which audiofile,
#     so the ecasound commands can be reconstructed.
#   midifade -audio -replay mix0.mid,mix1.mid v,p,f,q vocal.wav final.wav
#     those midifiles should automatically replay their audio-file.
# However the whole mechanism only redoes what can be done by producing
#   a mixed-down .wav, and then using that as subsequent audio input.
# Therefore forget the -replay option and the custom midi-comments.


# Curses interface from midiedit, midi stuff from midikbd.
# On exit, could print the equivalent muscript, or Perl,Python,or Lua ?
# 20130814: midifade could conceiveably take an a=auto for the value,
#   asking somehow for min, max, period, perhaps sin/tri/sawup/sawdown, and
#   then behave like panfarm on MIDI::ALSA. Probably need a child process...
# 20130815: Also, then what would the Up/Down/PgUp/PgDown/Home/End keys do ?
#   or, instead of n=new, perhaps w=wahwah and p=pan ?  74 wants also 71
#   should this be in our hypothetical midihub? Only really applies to 11,74

my $Version      = '1.8';
my $VersionDate  = '23mar2013';
my $OutputPort   = $ENV{'ALSA_OUTPUT_PORTS'};
my $ColsPerFader = 6;

eval 'require Curses'; if ($@) {
	die "you'll need to install the Curses module from www.cpan.org\n";
}
import Curses;
eval 'require MIDI::ALSA'; if ($@) {
	die "you'll need to install the MIDI::ALSA module from www.cpan.org\n";
}
import MIDI::ALSA;

# use Data::Dumper;

while ($ARGV[$[] =~ /^-(\w)/) {
	if ($1 eq 'd')      { $UseCurses = 0; shift;
	} elsif ($1 eq 'o') { shift; $OutputPort = shift;
	} else {
print <<EOT; exit 0;
Usage:
   midifade c13m71v120 c2m11v80 # 2 faders: cha2 cc11=80, cha13 cc71=120
   midifade -o 128:0            # outputs to port 0 of client 128
   midifade -v                  # prints the Version number
   perldoc midifade             # read the manual :-)
Version $Version   $VersionDate   http://www.pjb.com.au/midi
EOT
	}
}
my @Faders = ();  # LoL {$c,$m,$v}
my $IFader = undef;

my @note2letter=split / /,'C C D E E F F G G A B B c c d e e f f g g a b b';
my @note2acc = ('','#','','b','','','#','','#','','b','');

if (! MIDI::ALSA::client( "midifade pid=$$", 0, 1, 1 )) {
	die "can't start up the ALSA client\n";
}
foreach my $cl_po (split /,/, $OutputPort) {  # 1.3
	if ($cl_po ne '0') {
		if (! MIDI::ALSA::connectto( 1, $cl_po )) {  # 1.4
			die "can't connect to ALSA client $cl_po\n";
		}
	}
}
if (! MIDI::ALSA::start()) { die "can't start the ALSA client queue\n"; }
my $ID = MIDI::ALSA::id();

while ($ARGV[$[] =~ /^c(\d+)m(\d+)(v(\d+))?$/) {  # must start client first!
	add_new_fader($1,$2,$4); shift;
}

# eval 'sub END {all_sounds_off();}';

# ----- the Curses app...
initscr(); cbreak(); noecho(); nonl(); clear();
# start_color();  # can't seem to get it not to enforce white on black
# init_pair(1, COLOR_WHITE(), COLOR_BLACK());
# init_pair(2, COLOR_RED(), COLOR_RED());
# attrset(COLOR_PAIR(1));
# http://docstore.mik.ua/orelly/perl/cookbook/ch15_13.htm  BUT:
keypad(stdscr(),1);
$SIG{'INT'} = sub {exit 0;}; $SIG{'TERM'} = sub {exit 0;};
eval 'sub END {endwin();}';  # mustn't create call to endwin in nonCurses mode
display_clientstr();   # 1.6
display_screen();

while (1) {  # the loop
	my $c = getch();
	if ($c == ERR())   {
		# see man ncurses ==> man inopts
		timeout(-1);  # Shouldn't happen. Anyway, block next read
		# but could use this for a Message which vanishes after 2 sec
	} elsif ($c eq 'q')  { quit();
	} elsif ($c eq 'Q')  { exit 0;
	} elsif ($c eq 'D') { # or $c==KEY_DL() or $c==KEY_DC()) { too close to End
		if (@Faders) {
			splice @Faders, $IFader, 1;
			if ($IFader > $#Faders) { $IFader = $#Faders; }
		}
		display_screen();
	} elsif ($c eq 'n')    {
		my ($c,$m,$v) = new_fader_dialogue();
		if (defined $m) { add_new_fader($c,$m,$v); }
		display_screen();
	} elsif ($c == KEY_UP() or $c eq 'k')    {
		my ($c,$m,$v) = @{$Faders[$IFader]};
		$v += 1; if ($v > 127) { $v = 127; }
		$Faders[$IFader] = [$c,$m,$v]; output_fader($IFader); display_screen();
	} elsif ($c == KEY_DOWN() or $c eq 'j')  {
		my ($c,$m,$v) = @{$Faders[$IFader]};
		$v -= 1; if ($v < 0) { $v = 0; }
		$Faders[$IFader] = [$c,$m,$v]; output_fader($IFader); display_screen();
	} elsif ($c == KEY_LEFT() or $c eq 'h')  {
		if ($IFader>$[) { $IFader -= 1; } display_screen();
	} elsif ($c == KEY_RIGHT() or $c eq 'l') {
		if ($IFader<$#Faders) { $IFader += 1; } display_screen();
	} elsif ($c eq "\t") {
		if ($IFader<$#Faders) { $IFader += 1; } else { $IFader = $[; }
		display_screen();
	} elsif ($c == KEY_PPAGE() or $c eq 'K') {
		my ($c,$m,$v) = @{$Faders[$IFader]};
		$v += 10; if ($v > 127) { $v = 127; }
		$Faders[$IFader] = [$c,$m,$v];
		output_fader($IFader); display_screen();
	} elsif ($c == KEY_NPAGE() or $c eq 'J') {
		my ($c,$m,$v) = @{$Faders[$IFader]};
		$v -= 10; if ($v < 0) { $v = 0; }
		$Faders[$IFader] = [$c,$m,$v];
		output_fader($IFader); display_screen();
	} elsif ($c == KEY_HOME())  {
		my ($c,$m,$v) = @{$Faders[$IFader]};
		$Faders[$IFader] = [$c,$m,127];
		output_fader($IFader); display_screen();
	} elsif ($c == KEY_END())   {  # all_sounds_off ? or v=0?
		my ($c,$m,$v) = @{$Faders[$IFader]};
		$Faders[$IFader] = [$c,$m,0];
		output_fader($IFader); display_screen();
	}
}

#-------------- Infrastructure for the Curses version -------------
sub addl { my ($lin,$col,$str) = @_;
	move($lin,$col); addstr($str); clrtoeol();
}

sub all_sounds_off {
	foreach my $c (0..15) {
		MIDI::ALSA::output(MIDI::ALSA::controllerevent($c,120,0));
	}
	MIDI::ALSA::stop();
}

sub cc2str { my $m = $_[$[];
	if (! %c2s) { %c2s = (
		0, 'Bank Select (MSB)',
		32, 'Bank Select (LSB)',
		64, 'Sustain Pedal',
		96, 'Data Increment',
		1, 'Modulation (MSB)',
		33, 'Modulation (LSB)',
		65, 'Portamento on/off',
		97, 'Data Decrement',
		2, 'Breath Control (MSB)',
		34, 'Breath Control (LSB)',
		66, 'Sostenuto Pedal',
		98, 'non-reg param lsb',
		67, 'Soft Pedal',
		99, 'non-reg param msb',
		4, 'Foot Control (MSB)',
		36, 'Foot Control (LSB)',
		68, 'Legato Pedal',
		100, 'Reg Param (LSB)',
		5, 'Portamento Time (MSB)',
		37, 'Portamento Time (LSB)',
		69, 'Hold 2',
		101, 'Reg Param (MSB)',
		6, 'Data Entry (MSB)',
		38, 'Data Entry (LSB)',
		70, 'Sound Variation',
		7, 'Channel Volume (MSB)',
		39, 'Channel Volume (LSB)',
		71, 'Resonance, Q',
		8, 'Balance (MSB)',
		40, 'Balance (LSB)',
		72, 'Release Time',
		73, 'Attack Time',
		10, 'Pan (MSB)',
		42, 'Pan (LSB)',
		74, 'Cut-off Frequency',
		11, 'Expression (MSB)',
		43, 'Expression (LSB)',
		75, 'Decay Time',
		12, 'Effects Controller 1',
		76, 'Vibrato Rate',
		13, 'Effects Controller 2',
		77, 'Vibrato Depth',
		78, 'Vibrato Delay',
		84, 'Portamento Control',
		120, 'All Sound Off',
		121, 'Reset All Controllers',
		122, 'Local Control',
		91, 'Reverb Depth',
		123, 'All Notes Off',
		92, 'Tremolo Depth',
		124, 'Omni Off',
		93, 'Chorus Depth',
		125, 'Omni On',
		94, 'Celeste (De-tune)',
		126, 'Mono On (Poly off)',
		95, 'Phaser Depth',
		127, 'Poly On (Mono off)',
		);
	}
	return $c2s{$_[$[]} || '';
}

sub debug {
	open (T, '>>', '/tmp/debug');
	print T $_[$[],"\n";
	close T;
}

sub add_new_fader { my ($c,$m,$v) = @_;
	if (! defined $v) { $v = 64; }
	$c = 0+$c; $m = 0+$m; $v = 0+$v;
	my $i = $[; while ($i <= $#Faders) {
		my ($this_c,$this_m,$this_v) = @{$Faders[$i]};
		if ($this_c == $c and $this_m == $m) {  # a duplicate; update $v
			$Faders[$i] = [$c,$m,$v];  $IFader = $i;
			output_fader($IFader); return 1;
		} elsif ($this_c > $c or ($this_c == $c and $this_m > $m)) {
			splice @Faders, $i, 0, [$c,$m,$v];  $IFader = $i;
			output_fader($IFader); return 1;
		}
		$i += 1;
	}
	push @Faders, [$c,$m,$v]; $IFader = $#Faders;
	output_fader($IFader); return 1;
}

sub display_faders {
	foreach my $irow (1..$LINES-4) { move($irow, 0); clrtoeol(); } # XXX
	foreach my $i ($[ .. $#Faders) { display_fader($i); }
	refresh();
}

sub output_fader { my $i = $_[$[];
	if ($i < $[ or $i > $#Faders) { die "output_fader: i=$i\n"; }
	my ($c,$m,$v) = @{$Faders[$i]};
	my ($status,$time,$events ) = MIDI::ALSA::status();
	MIDI::ALSA::output(MIDI::ALSA::controllerevent($c,$m,$v,$time));
	MIDI::ALSA::syncoutput();
}
sub display_fader { my $i = $_[$[];
	if ($i < $[ or $i > $#Faders) { die "display_fader: i=$i\n"; }
	my $icol = 2 + $ColsPerFader * ($i-$[);
	my ($c,$m,$v) = @{$Faders[$i]};
	move($LINES-6,$icol); addstr(substr " c=$c   ",$[,6);
	move($LINES-5,$icol); addstr(substr " m=$m   ",$[,6);
	move($LINES-4,$icol); addstr(substr " v=$v   ",$[,6);
	my $top_of_fader = 0 + round(($LINES-7) * (128-$v) / 128);
	my $irow = 1; while ($irow < $top_of_fader) {
		move($irow, $icol); attrset(A_NORMAL()); addstr(q{ } x $ColsPerFader);
		$irow += 1;
	}
	while ($irow < ($LINES-6)) {
		move($irow, $icol+2);
		if ($i == $IFader) {
			attrset(A_REVERSE()); addstr('  '); attrset(A_NORMAL());
		} else {
			# attrset(A_REVERSE()); attrset(COLOR_PAIR(2));
			addstr('XX');
			# addstr("\e[41m  \e[0m");   # addstr escapes the escapes :-(
			# refresh(); print STDERR "\e[41m  \e[0m\e[D\e[D"; leaves bg wrong
			# attrset(A_NORMAL()); attrset(COLOR_PAIR(1));
		}
		$irow += 1;
	}
	if ($i == $IFader) {
		move(0,0); clrtoeol();
		my $s1 = cc2str($m);
		my $x = $icol + 4 - round(0.5 * length($s1));
		if ($x < 0) { $x = 0; } elsif ($x > $COLS) { $x = $COLS - length $s1; }
		display_clientstr();
		move(0,$x); addstr("$s1 "); # cc-str overwrites client-str if conflict
	}
	if ($i == $#Faders) {
		foreach my $irow (1..$LINES-4) { move($irow, $icol+6); clrtoeol(); }
	}
	move($LINES-4, ($IFader-$[) * $ColsPerFader + 4);
}

sub display_clientstr {   # 1.6
	my $s2 = "client $ID, midifade pid=$$";
	if (($icol+4) > 0.5*$COLS) { move(0,0);
	} else { move(0, $COLS-length($s2)-1);
	}
	addstr($s2);
	refresh();
}

sub display_keystrokes {
	$TopKeystrokesLine = $LINES-4;
	if ($Message) {
		move($LINES-2,2); clrtoeol();
		addl($LINES-2, round(0.4*($COLS - length $Message)) ,$Message);
		# move($LINES-3,2); clrtoeol();
		$Message = '';
	} else {
		addl($LINES-2,2,
		'Left,Right,Tab=move between faders  n=new  D=Delete  q=quit');
	}
	addl($LINES-1,2,
		  'k/Up/j/Down=+-1,  K/PageUp/J/PageDown=+-10,  Home=127,  End=0');
	refresh();
}

sub display_screen {
	move($LINES-3,1); hline($ACS_HLINE,$COLS-2);
	display_keystrokes();
	display_faders();
	refresh();
}

sub display_message {
	my ($y,$x); getyx($y,$x);
	$Message = $_[$[]; display_keystrokes();
	move($y,$x);
	refresh();
}

sub new_fader_dialogue {
	# Could introduce value=A meaning Auto like panfarm
	# and then ask for min, max, period, perhaps sin/tri/sawup/sawdown
	addl($LINES-3,2,'        Channel (0..15)  ?');
	addl($LINES-2,2,'MIDI-Controller (0..127) ?');
	addl($LINES-1,2,'          Value (0..127) ?');
	refresh();
	my @newfader = ();
	my $iline = 3;
	while ($iline > 0) {
		move($LINES-$iline,29);
		my $str; my $n;
		echo();
		if ($iline == 3) { $n = getnstr($str,2);   # 1.2
		} else { $n = getnstr($str,3);
		}
		noecho();
		if ($str) { $newfader[$[+3-$iline] = 0 + $str; }
		$iline -= 1;
	}
	return @newfader;
}

sub quit {
	move($LINES-2,2); clrtobot();
	addl($LINES-2,round(0.4*($COLS-24)),"OK to quit (y/n) ? ");
	my $c = getch();
	if ($c eq 'y') { exit 0; }
	display_keystrokes();
	move($LINES-4, ($IFader-$[) * $ColsPerFader + 4);
	refresh();
}

# ----------------------- infrastructure --------------------
sub round   { my $x = $_[$[];
	if ($x > 0.0) { return int ($x + 0.5); }
	if ($x < 0.0) { return int ($x - 0.5); }
	return 0;
}
sub deepcopy {
	use Storable;
	if (1 == @_ and ref($_[$[])) { return Storable::dclone($_[$[]);
	} else { my $b_ref = Storable::dclone(\@_); return @$b_ref;
	}
}

=pod

=head1 NAME

midifade - Provides faders generating midi-controller events

=head1 SYNOPSIS

 midifade c13m71v120 c2m11v80 # 2 faders: cha2 cc11=80, cha13 cc71=120
 midifade -o 128:0            # outputs to port 0 of client 128
 midifade -o TiMidity         # outputs to TiMidity
 midifade -v                  # prints the Version number
 perldoc midifade             # read the manual :-)

=head1 DESCRIPTION

B<Midifade> is a Curses and ALSA application which provides on-screen faders,
to control various midi-controllers on various midi-channels.

It uses a simple user-interface:
The Left and Right arrow keys move from one fader to the next,
the Up and Down arrow keys adjust the value of the current fader by 1,
the PageUp and PageDown keys adjust the value by 10,
and the Home and End keys set it to maximum (127) or minimum (0).

The faders are always displayed sorted by channel-number
then by midi-controller-number.

The available keystrokes are displayed in the bottom three lines of the screen.

It uses the B<Curses> CPAN module for the user-interface,
and the B<MIDI::ALSA> CPAN module to set up an ALSA client
which can communicate with your synth.

=head1 OPTIONS

=over 3

=item I<-o 128:0>

This example plays into the ALSA port 128:0.
This option allows I<midifade> to use the same port-specification
as the other alsa-utils, e.g. I<aplaymidi> and I<aconnect>. 
For port 0 of a client, the ":0" part of the port specification
can be omitted.
The port specification is taken from the ALSA_OUTPUT_PORTS
environment variable if none is given on the command line.
Since Version 1.3, you may supply a comma-separated list of ports,
e.g. B<-o 20,128:1>

If the ALSA port is specified as B<0> then I<midifade> will start
up without connecting to anything. This allows you, for example,
to use I<midifade> (assumed here to be starting up as ALSA-client
129 ; check with I<aconnect -ol>)
to control I<ecasound>:

 midifade -o 0 c0m9v102 c1m9v105 c2m9v96 c3m9v64

 ecasound -c -r -Md:alsaseq,129:0 \
  -a:1 -i drums.wav                -ea:200 -km:1,0,250,9,1 \
  -a:2 -i synth-chords.wav -epp:30 -ea:120 -km:1,0,150,9,2 \
  -a:3 -i bass-guitar_take-2.ewf   -ea:75  -km:1,0,100,9,3 \
  -a:4 -i brass-lead.wav   -epp:70 -ea:50  -km:1,0,100,9,4 \
  -a:1,2,3,4 -o loop,1 \
  -a:5,6 -i loop,1 \
  -a:5 -o alsa \
  -a:6 -o current-mix.wav

Here I chose midi-controller 9 because it isn't defined in General-MIDI,
and therefore General-MIDI-labels, useless in this context,
do not appear in the I<midifade> screen.
See I<ecasound_manpage.html> and I<examples.html> in the
I<ecasound> documentation for details of the B<-ea> and B<-km> options.

=item I<-v>

Prints version number.

=back

=head1 ARGUMENTS

=over 3

=item I<c14m74v123>

This example starts I<midifade> up with a fader on channel 14 (0..15),
midi-controller 74 (0..127), set initially to a value of 123 (0..127).
( In I<muscript>, that would be expressed I<cha14 cc74=123> )
Multiple arguments can be specified.
The B<c> and B<m> and B<v> bits must be in that order,
all in one word with no spaces.
The B<v> bit is optional; its default value is 64.

=back

=head1 CHANGES

 1.8, 20130323, D can now delete the only fader
 1.7, 20120831, -o "string" works
 1.6, 20120820, display_clientstr called at start
 1.5, 20111216, if  -o 0  then midifade starts up but connects to nothing
 1.4, 20111103, use the new MIDI-ALSA 1.11 to handle portnames
 1.3, 20111028, OutputPort can be a comma-separated list
 1.2, 20111027, add-new-fader dialogue allows 3-digit controller-nums
 1.1, 20111023, much irrelevant code eliminated; q asks y/n first
 1.0, 20111022, first working version

=head1 AUTHOR

Peter J Billam  http://www.pjb.com.au/comp/contact.html

=head1 CREDITS

Based on the I<Curses> and I<MIDI::ALSA> CPAN modules.

=head1 SEE ALSO

 aconnect -oil
 http://www.pjb.com.au/muscript/index.html#midi_in_a_stave
 http://www.pjb.com.au/muscript/gm.html#cc
 http://ecasound.sourceforge.net/ecasound/Documentation/examples.html
 http://search.cpan.org/perldoc?Curses
 http://search.cpan.org/perldoc?MIDI::ALSA
 http://www.pjb.com.au/midi

=cut