<?php
// Handles custom bulk actions for orders.

defined('ABSPATH') || exit;

class Bulk_Actions_Manager {
    public function __construct() {
        add_filter('bulk_actions-woocommerce_page_wc-orders', array($this, 'register_bulk_actions'));
        add_filter('handle_bulk_actions-woocommerce_page_wc-orders', array($this, 'handle_bulk_actions'), 10, 3);
    }

    public function register_bulk_actions($bulk_actions) {
        $bulk_actions['prepare_to_printing_export']       = __('Prepare to Printing Export', 'studiou-wc-ord-print-statuses');
        $bulk_actions['set_status_to_prepare_to_printing'] = __('Set Status to Prepare to Printing', 'studiou-wc-ord-print-statuses');
        $bulk_actions['set_status_to_in_printing']         = __('Set Status to In Printing', 'studiou-wc-ord-print-statuses');
        return $bulk_actions;
    }

    public function handle_bulk_actions($redirect_to, $action, $post_ids) {
        $known = array(
            'prepare_to_printing_export',
            'set_status_to_prepare_to_printing',
            'set_status_to_in_printing',
        );
        if (!in_array($action, $known, true)) {
            return $redirect_to;
        }
        if (!current_user_can('edit_shop_orders')) {
            wp_die(esc_html__('You do not have sufficient permissions to perform this action.', 'studiou-wc-ord-print-statuses'));
        }
        $post_ids = array_filter(array_map('intval', (array) $post_ids));
        if (empty($post_ids)) {
            return $redirect_to;
        }

        switch ($action) {
            case 'prepare_to_printing_export':
                return $this->prepare_to_printing_export($post_ids, $redirect_to);
            case 'set_status_to_prepare_to_printing':
                return $this->set_status_to_prepare_to_printing($post_ids, $redirect_to);
            case 'set_status_to_in_printing':
                return $this->set_status_to_in_printing($post_ids, $redirect_to);
        }
        return $redirect_to;
    }

    /**
     * Atomic order: pull rows, build the CSV in memory, then flip statuses, then
     * stream the file. If the export query returns nothing, statuses are still
     * advanced (the spec requires it) but the user is told no CSV was produced.
     */
    private function prepare_to_printing_export($post_ids, $redirect_to) {
        $orders_data = Studiou_DB_Manager::get_orders_for_printing($post_ids);
        $csv_data    = !empty($orders_data) ? $this->generate_csv($orders_data) : '';

        $updated = Studiou_DB_Manager::set_orders_to_prepare_printing($post_ids);
        $this->notify_moved_count($updated, 'to-print');

        if ($csv_data === '') {
            UtilsLog::message(
                __('No exportable line items were found for the selected orders. CSV was not generated.', 'studiou-wc-ord-print-statuses'),
                'warning'
            );
            return $redirect_to;
        }

        $this->output_csv($csv_data, 'prepare_to_printing_export.csv'); // exits
    }

    private function set_status_to_prepare_to_printing($post_ids, $redirect_to) {
        $updated = Studiou_DB_Manager::set_orders_to_prepare_printing($post_ids);
        $this->notify_moved_count($updated, 'to-print');
        return add_query_arg('bulk_action', 'marked_prepare_to_printing', $redirect_to);
    }

    private function set_status_to_in_printing($post_ids, $redirect_to) {
        $updated = Studiou_DB_Manager::set_orders_to_in_printing($post_ids);
        $this->notify_moved_count($updated, 'in-print');
        return add_query_arg('bulk_action', 'marked_in_printing', $redirect_to);
    }

    /**
     * Emit a "%d orders moved to …" notice unless zero orders were actually
     * changed — in that case the "skipped because terminal status" warning
     * from Studiou_DB_Manager is more informative on its own.
     */
    private function notify_moved_count($count, $slug) {
        if ($count <= 0) {
            return;
        }
        if ($slug === 'to-print') {
            $message = _n(
                '%d order moved to "Prepare to Printing".',
                '%d orders moved to "Prepare to Printing".',
                $count,
                'studiou-wc-ord-print-statuses'
            );
        } else {
            $message = _n(
                '%d order moved to "In Printing".',
                '%d orders moved to "In Printing".',
                $count,
                'studiou-wc-ord-print-statuses'
            );
        }
        UtilsLog::message(sprintf($message, $count), 'success');
    }

    private function generate_csv($data) {
        $output = fopen('php://temp', 'w+');
        // Explicit empty-string escape suppresses the PHP 8.4 deprecation
        // notice for the implicit '\\' default.
        fputcsv($output, array_keys((array) $data[0]), ',', '"', '');
        foreach ($data as $row) {
            fputcsv($output, (array) $row, ',', '"', '');
        }
        rewind($output);
        $csv = stream_get_contents($output);
        fclose($output);
        return $csv;
    }

    /**
     * Stream CSV with UTF-8 BOM so Excel on Windows reads diacritics correctly.
     * If output has already started (some upstream code printed something) we
     * cannot reliably stream a CSV download — bail with a clear error rather
     * than echoing CSV bytes into an HTML page.
     */
    private function output_csv($csv_data, $filename) {
        if (headers_sent($file, $line)) {
            UtilsLog::log(sprintf(
                'output_csv: headers already sent from %s:%d — aborting CSV stream.',
                $file,
                $line
            ));
            wp_die(esc_html__(
                'The CSV export could not be streamed because output had already started. Check for plugin/theme code that prints before headers are sent.',
                'studiou-wc-ord-print-statuses'
            ));
        }
        nocache_headers();
        header('Content-Type: text/csv; charset=utf-8');
        header('Content-Disposition: attachment; filename="' . $filename . '"');
        echo "\xEF\xBB\xBF" . $csv_data; // UTF-8 BOM
        exit;
    }
}