Colour Picker template for Block Lab

block-colour-picker.php

<?php
$field = 'colour-picker';

$color = block_value( $field );
if ( '#' === substr( $color, 0, 1 ) ) {
	$rgb = str_split( str_replace( '#', '', $color ), 2 );
	$r   = hexdec( $rgb[0] );
	$g   = hexdec( $rgb[1] );
	$b   = hexdec( $rgb[2] );
} elseif ( 'rgb' === substr( $color, 0, 3 ) ) {
	$rgb = explode( ',', str_replace( array( 'rgba', '(', ')', ' ' ), '', $color ) );
	$r   = $rgb[0];
	$g   = $rgb[1];
	$b   = $rgb[2];
}
$text_color = '#fff';
if ( ( $r * 0.299 ) + ( $g * 0.587 ) + ( $b * 0.114 ) > 186 ) {
	$text_color = '#000';
}
?>

<div style="background: <?php block_field( $field ); ?>; padding: 1em; border: none; box-shadow: inset 0 0 0 5px rgba(0,0,0,0.2); text-align: center;">
	<code style="color: <?php echo esc_attr( $text_color ); ?>; text-transform: uppercase; font-size: 1.5em; background: none;">
		<?php block_field( $field ); ?>
	</code>
</div>