#!/usr/bin/perl

use strict; use warnings; use utf8;

sub hexTuple {
	my ($r, $g, $b) = @_;
	return sprintf('%02x%02x%02x', int(255*$r+0.5), int(255*$g+0.5), int(255*$b+0.5));
}
sub hsvHex {
	my ($hue, $sat, $val ) = @_;
	my $h = int($hue * 6);
	my $f = $hue * 6 - $h;
	my $p = $val * (1 - $sat);
	my $q = $val * ( 1 - $f * $sat);
	my $t = $val * ( 1 - (1-$f) * $sat);

	return hexTuple($val, $t, $p) if $h == 0 or $h == 6;
	return hexTuple($q, $val, $p) if $h == 1;
	return hexTuple($p, $val, $t) if $h == 2;
	return hexTuple($p, $q, $val) if $h == 3;
	return hexTuple($t, $p, $val) if $h == 4;
	return hexTuple($val, $p, $q) if $h == 5;

	die $h;
}

# https://en.wikipedia.org/wiki/HSL_and_HSV#From_HSL
sub hslHex {
	my ($hue, $sat, $lig ) = @_;
	my $h = ($hue * 6);
	my $c = (1 - abs(2.0*$lig - 1)) * $sat;
	my $h_mod_2 = $h - 2*int($h/2);
	my $x = $c * (1 - abs($h_mod_2 - 1));
	my ($r, $g, $b);
	my $m = $lig - $c / 2.0;

	return hexTuple($c + $m, $x + $m,  0 + $m) if $h < 1 or $h == 6;
	return hexTuple($x + $m, $c + $m,  0 + $m) if $h < 2;
	return hexTuple( 0 + $m, $c + $m, $x + $m) if $h < 3;
	return hexTuple( 0 + $m, $x + $m, $c + $m) if $h < 4;
	return hexTuple($x + $m,  0 + $m, $c + $m) if $h < 5;
	return hexTuple($c + $m,  0 + $m, $x + $m) if $h < 6;

	die $h;
}

my @hexDigit = split //, '0123456789abcdef';
my %hexValue = map(
       	(lc($hexDigit[$_]) => $_, uc($hexDigit[$_]) => $_ ),
       	0..15 );

sub min {
	my $min = shift;

	for (@_) { $min = $_ if $_ < $min }

	return $min;
}

sub max {
	my $max = shift;

	for (@_) { $max = $_ if $_ > $max }

	return $max;
}

sub hexToHSL {
	my $hexTriplet = shift;
	my ( $r,$g,$b ) = $hexTriplet =~ /^#?(..)(..)(..)/;
	for ($r,$g,$b) {
		my @d = split(//);
		$_ = 16 * $hexValue{$d[0]} + $hexValue{$d[1]};
	}

	warn "$hexTriplet -> $r:$g:$b";

	for ($r, $g, $b ) { $_ = $_ / 255.0 }

	my $M = max($r, $g, $b);
	my $m = min($r, $g, $b);
	my $C = $M - $m;

	my $h;
	if ($C == 0) {
		$h = 0;
	}
	elsif ( $r == $M ) {
		$h = ($g-$b)/$C;
		$h -= 6*int($h/6.0);
	}
	elsif ( $g == $M ) {
		$h = ($b-$r)/$C + 2;
	}
	elsif ( $b == $M ) {
		$h = ($r-$g)/$C + 4;
	}
	else { die "$C, $M, $r, $g, $b"; }

	my $H = 60 * $h;
	my $L = ($M + $m) / 2;

	my $S = ( $L <= 0.5 ) ? $C/(2*$L) : $C / (2-2*$L);

	return( $H, $S, $L );
}

my $baseColorHSV = [ hexToHSL('#935ff2') ];
my $baseColorHue = $baseColorHSV->[0];
warn sprintf( 'H:%1.4f S:%1.4f L:%1.4f', @$baseColorHSV );
warn sprintf( 'H:%1.4f S:%1.4f L:%1.4f', hexToHSL('#3e148c') );

my $baseTheme = "AppTheme.NoActionBar";

# # hsb
# for( my $hue = 0; $hue < 360; $hue += 15 ) {
# 	printf "<style name=\"%s.%d\" parent=\"%s\">\n",
# 		$baseTheme, $hue, $baseTheme;
# 	printf "  <item name=\"colorPrimary\">#%s</item>\n",
#        		hsvHex($hue/360.0, 0.61, 0.95);
# 	printf "  <item name=\"colorPrimaryDark\">#%s</item>\n",
#        		hsvHex($hue/360.0, 0.86, 0.55);
# 	printf "  <item name=\"colorAccent\">#%s</item>\n",
#        		hsvHex(($hue-4)/360.0, 0.72, 0.82);
# 	printf "  <item name=\"drawer_background\">#ffffffff</item>\n";
# 	printf "  <item name=\"table_row_dark_bg\">#28%s</item>\n",
#        		hsvHex($hue/360.0, 0.65, 0.83);
# 	printf "  <item name=\"table_row_light_bg\">#28%s</item>\n",
#        		hsvHex($hue/360.0, 0.20, 1.00);
# 	printf "  <item name=\"header_border\">#80%s</item>\n",
#        		hsvHex(($hue+6)/360.0, 0.86, 0.55);
# 	printf "</style>\n";
# }

# HSL
hslStyleForHue($baseColorHue);
for( my $hue = 0; $hue < 360; $hue += 15 ) {
	hslStyleForHue($hue, $baseTheme);
}

sub hslStyleForHue {
	my $hue = shift;
	my $base = shift;

	if ($base) {
		printf "<style name=\"%s.%d\" parent=\"%s\">\n",
			$baseTheme, $hue, $baseTheme;
	}
	else {
		printf "<style name=\"%s\">\n",
			$baseTheme;
		printf "  <item name=\"windowActionBar\">false</item>\n";
		printf "  <item name=\"windowNoTitle\">true</item>\n";
		printf "  <item name=\"textColor\">#d0000000</item>\n";
	}
	printf "  <item name=\"colorPrimary\">#%s</item>\n",
       		hslHex($hue/360.0, 0.60, 0.60);
	printf "  <item name=\"colorPrimaryTransparent\">#00%s</item>\n",
       		hslHex($hue/360.0, 0.60, 0.60);
	printf "  <item name=\"colorAccent\">#%s</item>\n",
       		hslHex($hue/360.0, 0.85, 0.50);
	printf "  <item name=\"drawer_background\">#ffffffff</item>\n";
	printf "  <item name=\"table_row_dark_bg\">#%s</item>\n",
       		hslHex($hue/360.0, 0.85, 0.95);
	printf "  <item name=\"table_row_light_bg\">#%s</item>\n",
       		hslHex($hue/360.0, 0.85, 0.98);
	printf "</style>\n";
}