#!/usr/local/bin/perl

# crd2sb - convert chordpro files to songbook (LaTeX style)

# Usage: crd2sb filename.crd [filename2.crd] . . [filenamen.crd]

# The input files are "*.crd" and the output files are "*.tex" (in the
# current directory).

# $Id: crd2sb,v 1.9 1997/12/05 19:25:05 abel Exp $

# (C)Copyright 1997 Abel Chow <abel@g2networks.com>

# You may distribute under the terms of the Artistic License,
# as specified in the relnotes.txt file.

use File::Basename;

$debuglevel = 0;
$date = localtime;

sub Init
{
    $title = "";
    $key = "";
    $copyright = "Unknown";
    $wandm = "Unknown";
    $sref = "";
    $ccli = "";
    $lyrics = "";

    $nextenv = "SBVerse";
}
    
sub EndSong
{
    unless ($title) {
	print STDERR "$file:$.: No title defined for song.\n";
	Init();
	return;
    }
    $ccli = "\\NotCCLIed" if $copyright =~ /\bPublic Domain\b/;

    print STDERR "$file:$.: key undefined for \"$title\".\n" unless $key;
    print STDERR "$file:$.: copyright info undefined for \"$title\".\n" if $copyright eq "Unknown";
    print STDERR "$file:$.: author undefined for \"$title\".\n" if $wandm eq "Unknown";
#    print STDERR "$file:$.: scripture ref. undefined for \"$title\".\n" unless $sref;
    print STDERR "$file:$.: CCLI status undefined for \"$title\".\n" unless $ccli;

    if ($env) {
	DoEnd($env);
    }

    print "% This file is machine generated.  Do not edit.\n";
    print "% crd2sb $file\n";
    print "% created on $date\n";
    print "\\begin{song}{$title}{$key}\n";
    print "  {$copyright}\n  {$wandm}\n  {$sref}\n  {$ccli}\n";
    print "$lyrics";
    print "\\end{song}\n";
    Init();
}

sub DoNewSong
{
    EndSong();
    Init();
}

sub DoSubTitle
{
    ($_) = @_;
    # figure out if it's a copyright
    if (s/\(C\)// + s/\bCopyright\b//) {
	s/^\s+//;
	s/\s+$//;
	$copyright = $_;
	return;
    }
    if (/Public Domain/) {
	$copyright = $_;
	return;
    }
    s/^W&M://;
    s/^\s+//;
    s/\s+$//;
    $wandm = $_;
}

sub DoComment
{
    ($_) = @_;
    print STDERR "$file:$.: > $_\n" if $debuglevel > 0;
    if (($p) = /^tex:\s*(.*)/) {
	$lyrics .= "$p\n";
	return;
    }
    if (($p) = /^note:\s*(.*)/) {
	$lyrics .= "\\SBMargNote{$p}\n";
	return;
    }
    if (($p) = /^intro:\s*(.*)/) {
	$p =~ s/#/\$\\sharp\$/g;
	$p =~ s/b/\$\\flat\$/g;
	$p =~ s/\|/\$|\$/g;
	$lyrics .= "\\SBIntro{\\ChFont $p}\n";
	return;
    }
    if (/^section:/) {
	$nextenv = "SBSection";
	return;
    }
    # figure out if there's a CCLI ref anywhere
    $ccli = "\\CCLIed" if /\bccli\b/i;
    # key setting
    if (/^\s*key:\s*(.*)/) {
	my($k) = $1;
	if ($k !~ /^[A-G]\S*/) {
	    print STDERR "$file:$.: invalid key $k\n";
	}
	$k =~ s/#/\$\\sharp\$/g;
	$k =~ s/b/\$\\flat\$/g;
	$key = $k;
	return;
    }
    $sref = $1 if /^\s*sref:\s*(.*)/;
}

sub DoBegin
{
    my($myenv) = @_;
    printf STDERR "$file:$.: missing env $env" if $env;
    $env = $myenv;
    $lyrics .= "\\begin{$env}\n";
    $first = 1;
}

sub DoEnd
{
    print STDERR "$file:$.: mismatched quote\n" if $quote;
    $quote = 0;
    printf STDERR "$file:$.: missing env $env\n" unless ($env);
    $lyrics .= "\\end{$env}\n";
    $env = "";
}

unless (@ARGV) {
    print "usage: crd2sb filename.crd [filename2.crd] ... [filenamen.crd]\n"
}

Init();
foreach $file (@ARGV) {
    ($base, $path, $type) = fileparse($file, '\.crd');
    unless ($type) {
	print STDERR "$file: not a Chordpro (*.crd) file\n";
	next;
    }
    $outfile = "$base.tex";
    print STDERR "#### $file -> $outfile ####\n"
	if $debuglevel > 0;
    unless (open(INFILE, $file)) {
	print STDERR "$file: $!\n";
	exit;
    }
    close(STDOUT);
    unless (open(STDOUT, ">$outfile")) {
	print STDERR "$outfile: $!\n";
	exit;
    }
    while (<INFILE>) {
	if (/^#\s+(.*)/) {
	    DoComment($1);
	    next;
	}
	next if /^#/;
	# directive
	if (m/^\s*{([^\}:]+)(:\s*([^\}]*))?}/) {
	    # title
	    if ($1 eq "title" || $1 eq "t") {
		$title = $3; next;
	    }
	    if ($1 eq "subtitle" || $1 eq "st") {
		DoSubTitle($3); next;
	    }
	    if ($1 eq "comment" || $1 eq "c") {
		DoComment($3); next;
	    }
	    # new_song
	    if ($1 eq "new_song" || $1 eq "ns") {
		DoNewSong(); next;
	    }
	    if ($1 eq "start_of_chorus" || $1 eq "soc") {
		DoBegin("SBChorus"); next;
	    }
	    if ($1 eq "end_of_chorus" || $1 eq "eoc") {
		DoEnd("SBChorus"); next;
	    }
	    next;
	}
	if (/{/ || /}/) {
	    print STDERR "$file:$.: unmatched brace\n";
	}

	# strip blank spaces and comments
	s/\s+/ /;
	s/^\s//;
	s/\s$//;
	s/&/\\&/;
	unless ($_) {		# blank line
	    DoEnd() if $env;
	    next;
	}
	while (/"/) { # " 
	       if ($quote) {
		   $quote = 0 if (s/"/\'\'/); # " }
	       }
	       else {
		   $quote = 1 if (s/"/\`\`/); # " }
	       }
	   }
	# protect the parens in chords
	s/(\[[^\[\]]*)\(/$1</g;
	s/\)([^\[\]]*\])/>$1/g;
	s/\(/{\\em /g;
	s/\)/}/g;
	tr/\<\>/\(\)/;

	s/\|/\$|\$/g;
	s/\[([^\[\]]*)\]-/\\Ch{$1}{\\SBem}/g;
	s/\[([^\[\]]*)\]([A-Za-z0-9,;:.!"'`]+)/\\Ch{$1}{$2}/g; #'`
	s/\[([^\[\]]*)\]/\\Ch{$1}{}/g;#}}
	s/\.\.\./\\ldots{}/g;

	unless ($env) {
	    DoBegin($nextenv) unless $env;
	    $nextenv = "SBVerse";
	}
	$lyrics .= "\n" if $env && !$first;
	$first = 0;
	$lyrics .= "$_\n";
    }
    DoNewSong();
}