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<?php
/**
 * Gravity Perks // GP Read Only + GP Copy Cat // Only Disable Checkboxes Checked by GP Copy Cat
 * http://gravitywiz.com/documentation/gp-read-only/
 * http://gravitywiz.com/documentation/gp-copy-cat/
 *
 * Instructions:
 *
 * 1 - Copy and paste the snippet into your theme's functions.php file.
 * 2 - Add the 'gw-set-checked-as-read-only' in the CSS Class Name setting for the desired field.
 * 3 - Enable the Read Only setting on the Perks tab for the same field.
 *
 * This pairs well with GP Copy Cat where you're copying one checkbox field to another. The target field can then
 * have additional checkboxes checked but the copied checkboxes are "locked". Also pairs well with GP Limit Checkboxes
 * where you want to limit the total number of checkboxes that can be checked.
 */
add_filter( 'gform_field_content', function( $content, $field, $value, $entry_id, $form_id ) {

    if( $field->is_form_editor() || $field->is_entry_detail() || ! gw_has_css_class( $field, 'gw-set-checked-as-read-only' ) ) {
        return $content;
    }

	// Un-disable all inputs by default - AND - add onkeypress event. // Unset the hidden input that captures checked disabled checkboxes.
	$onkeypress = 'var idBits = jQuery( this ).attr( "id" ).split( "_" ); jQuery( "#gwro_hidden_capture_' . $form_id . '_" + idBits[2] + "_" + idBits[3] ).val( this.checked ? this.value : "" ); console.log( this );';
	$content = str_replace( "disabled='disabled'", " onkeypress='{$onkeypress}' onclick='{$onkeypress}'", $content );

	$entry = GFFormsModel::get_current_lead();
    if( ! $entry ) {
        return $content;
    }

    $form        = GFAPI::get_form( $form_id );
    $gp_copy_cat = new GP_Copy_Cat();
    $copy_fields = $gp_copy_cat->get_copy_cat_fields( $form );
	$values      = array();

    // find the first source field that targets the current field and isn't hidden
    foreach( $copy_fields as $group ) {
        foreach( $group as $copy_field ) {
	        if ( intval( $copy_field['target'] ) != $field->id ) {
		        continue;
	        }
	        $source_field = GFFormsModel::get_field( $form, $copy_field['source'] );
	        if ( GFFormsModel::is_field_hidden( $form, $source_field, array() ) ) {
		        continue;
	        }
	        foreach ( $entry as $input_id => $value ) {
		        if ( intval( $input_id ) == $source_field->id ) {
			        $values[] = $value;
		        }
	        }
	        break 2;
        }
    }

    $values = array_filter( $values );
    if( empty( $values ) ) {
	    return $content;
    }

    // Disable checkboxes by value.
    foreach( $values as $value ) {
	    $search  = sprintf( "value='%s'", esc_attr( $value ) );
	    $replace = sprintf( "%s disabled='disabled'", $search );
	    $content = str_replace( $search, $replace, $content );
    }

    return $content;
}, 10, 5 );

if( ! function_exists( 'gw_has_css_class' ) ) {
	function gw_has_css_class( $form_or_field, $class ) {
		if( ! isset( $form_or_field['cssClass'] ) ) {
			return false;
		} else {
			$classes = array_map( 'trim', explode( ' ', $form_or_field['cssClass'] ) );
			return in_array( $class, $classes );
		}
	}
}