<?php

namespace Picea\ControlStructure;

enum PrintActionEnum : string {
    case prepend = "prepend";
    case default = "default";
    case append = "append";
    # case both = "both";
}

class SectionToken implements ControlStructure {

    public array $token = [ "section", "endsection" ];

    protected PrintActionEnum $action = PrintActionEnum::default;

    public function parse(\Picea\Compiler\Context &$context, ?string $arguments, string $token, array $options = []) : string
    {
        if (in_array('prepend', $options)) {
            $this->action = PrintActionEnum::prepend;
        }
        elseif (in_array('append', $options)) {
            $this->action = PrintActionEnum::append;
        }

        switch($token) {
            case "section":
                return $this->printSection($context, $arguments);

            case "endsection":
                if ( empty($context->sections) ) {
                    throw new \RuntimeException("A section closing tag {% endsection %} was found without an opening {% section %} tag");
                }

                return $this->printEndSection($context);
        }
    }
    
    protected function printSection($context, ? string $arguments) : string
    {
        list($name, $options) = array_pad(explode(',', $arguments, 2), 2, null);

        if ( $options ?? false ) {
            $options = eval("return $options;");
        }

        if ( ! ctype_alnum(str_replace([".", "\"", "'", "-", "_", ":"], "", $name)) ) {
            throw new \RuntimeException("Your section named `{$name}` contains invalid character. Allowed are only letters, numbers, dashes, underscores and dots");
        }

        $context->sections[] = [
            'name' => $name,
            'options' => $options,
        ];

        $action = $options['action'] ?? $this->action->value;

        if (! in_array($action, ['prepend', 'append', 'default'])) {
            throw new \RuntimeException("An unsupported action `$action` was given as an option of a {% section %} tag");
        }

        $order = $options['order'] ?? "count(\$___class__template->sectionList[$name]['$action'])";

        return "<?php \$___class__template->sectionList[$name] ??= [ 'prepend' => [], 'append' => [], 'default' => [] ];" .
                      "\$___class__template->sectionList[$name]['$action'][] = [ 
                      'order' => $order, 
                      'callback' => function() use (\$picea, \$___class__template, \$___global_variables, \$___variables, \$__event) {" .
                          "extract(\$___global_variables); extract(\$___variables, \EXTR_OVERWRITE);" .
                          "\$___class__template->sectionStack[] = $name;" .
                          "\$__event->eventExecute(\Picea\Event\Builder\ClassTemplateRenderSection::class, $name);?>";
    }

    protected function printEndSection($context) : string
    {            
        $section = array_pop($context->sections);
        $build = $context->extendFrom ? "!empty(\$___class__template->sectionStack) && \$___class__template->renderSection({$section['name']}, false);" : "\$___class__template->renderSection({$section['name']}, false);";

        return "<?php \$__event->eventExecute(\Picea\Event\Builder\ClassTemplateRenderSectionDone::class, {$section['name']});" .
                "array_pop(\$___class__template->sectionStack); }];" .
                $build .
                "?>";

    }
}