Takes a `pdftk` field dump and turns it into a PHP-copyable output.

pdf-fields.php

<?php

    // Usage example: pdftk stuff.pdf dump_data_fields | php pdf-fields.php

    $stdin = file('php://stdin');
    // print_r($stdin);
    $data = [];
    $i = 0;
    foreach($stdin as $idx => $line) {
        $chunks = explode(': ', $line);
        $name = trim($chunks[0]);
        if ($name === '---') {
            $i += 1;
        }
        if (isset($chunks[1])) {
            $value = trim($chunks[1]);
            if ($name === 'FieldStateOption') {
                $data[$i][$name][] = $value;
            } else {
                $data[$i][$name] = $value;
            }
        }
    }
    
    foreach($data as $i => $field) {
        $fieldName = $field['FieldName'];
        $options = '';
        if ($field['FieldType'] === 'Button') {
            $options = ' // ' . implode(', ', $field['FieldStateOption']);
        }
        echo "'$fieldName' => '$i $fieldName',$options\n";
    }
?>