<?php
defined('ABSPATH') || exit;

/** Optional, user-owned lessons. Reading progress never certifies financial data. */
final class OWWC_Guide {
    const META = 'owwc_guide_v1';
    public static function init(): void {
        add_action('admin_post_owwc_guide', [__CLASS__, 'save']);
    }
    public static function lessons(): array {
        static $content;
        if ($content === null) {
            $content = (require dirname(OWWC_FILE) . '/includes/guide-translations.php');
        }
        return array_values(apply_filters('owwc_guide_lessons', $content['lessons'] ?? []));
    }
    public static function state(): array {
        $saved = get_user_meta(get_current_user_id(), OWWC_User_State::key(self::META), true);
        $saved = is_array($saved) ? $saved : [];
        $ids = array_column(self::lessons(), 'id');
        return [
            'status'=>in_array($saved['status'] ?? '', ['active','later','complete'], true) ? $saved['status'] : 'new',
            'step'=>in_array($saved['step'] ?? '', $ids, true) ? $saved['step'] : $ids[0],
            // Keep Pro progress when Pro is temporarily inactive, but only count available lessons in the UI.
            'seen'=>is_array($saved['seen'] ?? null) ? array_values(array_filter($saved['seen'], 'is_string')) : [],
        ];
    }
    /** Reading completion belongs to this user and the currently available lessons. */
    public static function completed(): bool {
        $state = self::state();
        return 'complete' === $state['status'] && !array_diff(array_column(self::lessons(), 'id'), $state['seen']);
    }
    public static function change(string $operation, string $lesson = ''): array {
        if (!current_user_can('manage_woocommerce')) {
            // phpcs:ignore WordPress.Security.EscapeOutput.ExceptionNotEscaped -- Plain-text validation error is caught by the admin handler and escaped for HTML or sent as JSON to textContent; escaping here would corrupt those messages.
            throw new InvalidArgumentException(__('Store-management access required.', 'orderworth')); }
        $state = self::state(); $ids = array_column(self::lessons(), 'id');
        if (!in_array($operation, ['start','later','resume','next','replay'], true)) {
            // phpcs:ignore WordPress.Security.EscapeOutput.ExceptionNotEscaped -- Plain-text validation error is caught by the admin handler and escaped for HTML or sent as JSON to textContent; escaping here would corrupt those messages.
            throw new InvalidArgumentException(__('Unknown guide action.', 'orderworth')); }
        if ($lesson !== '' && !in_array($lesson, $ids, true)) {
            // phpcs:ignore WordPress.Security.EscapeOutput.ExceptionNotEscaped -- Plain-text validation error is caught by the admin handler and escaped for HTML or sent as JSON to textContent; escaping here would corrupt those messages.
            throw new InvalidArgumentException(__('This lesson is unavailable in the active edition.', 'orderworth')); }
        if ($operation === 'replay') { $state = ['status'=>'active','step'=>$ids[0],'seen'=>[]]; }
        elseif ($operation === 'later') { $state['status']='later'; if ($lesson !== '') { $state['step']=$lesson; } }
        elseif ($operation === 'next') {
            if ($lesson === '') {
            // phpcs:ignore WordPress.Security.EscapeOutput.ExceptionNotEscaped -- Plain-text validation error is caught by the admin handler and escaped for HTML or sent as JSON to textContent; escaping here would corrupt those messages.
            throw new InvalidArgumentException(__('Choose a lesson first.', 'orderworth')); }
            $state['seen']=array_values(array_unique(array_merge($state['seen'], [$lesson])));
            $index=array_search($lesson, $ids, true);
            $remaining=array_values(array_diff($ids,$state['seen']));
            $state['step']=$index+1 < count($ids) ? $ids[$index+1] : ($remaining[0] ?? $lesson);
            $state['status']=!$remaining ? 'complete' : 'active';
        } else { $state['status']='active'; if ($lesson !== '') { $state['step']=$lesson; } }
        update_user_meta(get_current_user_id(), OWWC_User_State::key(self::META), $state);
        if (get_user_meta(get_current_user_id(), OWWC_User_State::key(self::META), true) !== $state) {
            // phpcs:ignore WordPress.Security.EscapeOutput.ExceptionNotEscaped -- Plain-text validation error is caught by the admin handler and escaped for HTML or sent as JSON to textContent; escaping here would corrupt those messages.
            throw new RuntimeException(__('Guide progress could not be saved. Retry after checking the database.', 'orderworth')); }
        return $state;
    }
    public static function save(): void {
        OWWC_Admin::authorize();
        OWWC_Admin::validate_nonce_input(); check_admin_referer('owwc_guide');
        $operation=isset($_POST['guide_action']) && is_string($_POST['guide_action']) ? sanitize_key(wp_unslash($_POST['guide_action'])) : '';
        $lesson=isset($_POST['lesson']) && is_string($_POST['lesson']) ? sanitize_key(wp_unslash($_POST['lesson'])) : '';
        try { $state=self::change($operation,$lesson); }
        catch (Throwable $e) { wp_die(esc_html(OWWC_Settings::translate_error($e->getMessage())), 'OrderWorth', ['response'=>400]); return; }
        $destination = $operation === 'later' ? OWWC_Admin::url() : OWWC_Admin::url(['view'=>'tutorial','lesson'=>$state['step']]);
        if ($operation === 'next' && self::completed()) { $destination = OWWC_Admin::url(['view'=>'tutorial']); }
        wp_safe_redirect($destination);
        exit;
    }
    private static function button(string $operation, string $label, string $lesson = '', bool $primary = false): void {
        echo '<form class="owwc-guide-action" action="' . esc_url(admin_url('admin-post.php')) . ('" method="post">' . '<input type="hidden" name="action" value="owwc_guide">' . '<input type="hidden" name="guide_action" value="') . esc_attr($operation) . '"><input type="hidden" name="lesson" value="' . esc_attr($lesson) . '">';
        // Several forms share the nonce name, but DOM IDs must remain unique.
        echo '<input type="hidden" id="' . esc_attr('owwc-guide-' . $operation . '-' . $lesson . '-nonce') . '" name="_wpnonce" value="' . esc_attr(wp_create_nonce('owwc_guide')) . '">';
        echo '<button class="button' . ($primary ? ' button-primary' : '') . '">' . esc_html($label) . '</button></form>';
    }
    public static function banner(): void {
        $state=self::state();
        if (in_array($state['status'], ['later','complete'], true)) { return; }
        echo ('<section class="owwc-card owwc-guide-banner" aria-labelledby="owwc-quickstart-title">' . '<div>' . '<h2 id="owwc-quickstart-title">' . ($state['status'] === 'new' ? esc_html__('Your first useful report', 'orderworth') : esc_html__('Continue your quickstart', 'orderworth')) . '</h2>' . '<p>' . esc_html__('Optional lessons: add costs, confirm expenses, run a report and review missing data. Progress belongs to your WordPress account. Reopen anytime from Quickstart.', 'orderworth') . '</p>' . '</div>' . '<div class="owwc-guide-actions">');
        self::button($state['status'] === 'new' ? 'start' : 'resume', $state['status'] === 'new' ? __('Start quickstart', 'orderworth') : __('Resume quickstart', 'orderworth'), '', true);
        self::button('later',__('Not now', 'orderworth'));
        echo '</div></section>';
    }
    public static function report_completed(array $scan): void {
        if (!current_user_can('manage_woocommerce') || (int) ($scan['owner'] ?? 0) !== get_current_user_id()) { return; }
        $groups=array_map(static function($g){return ['from'=>$g['from'],'to'=>$g['to'],'total'=>OWWC_Reports::group_total($g)];},$scan['groups']);
        update_user_meta(get_current_user_id(),OWWC_User_State::key('owwc_guide_report'),['at'=>time(),'groups'=>$groups,'currency'=>OWWC_Reports::unit()['currency'],'decimals'=>OWWC_Reports::unit()['decimals']]);
    }
    public static function review_saved($order): void {
        if (!current_user_can('manage_woocommerce')) { return; }
        update_user_meta(get_current_user_id(),OWWC_User_State::key('owwc_guide_review'),['id'=>$order->get_id(),'signature'=>OWWC_Profit_Calculator::review_signature($order)]);
    }
    public static function checks(): array {
        if (!current_user_can('manage_woocommerce')) { return []; }
        $native=OWWC_Setup::ready(); $settings=OWWC_Settings::get();
        $sample=[];
        if ($native) {
            foreach (['simple','variation'] as $type) {
                foreach (wc_get_products(['type'=>$type,'limit'=>5,'orderby'=>'ID','order'=>'DESC','return'=>'objects']) as $product) {
                    $sample[]=$product->get_cogs_value();
                }
            }
        }
        $found=count(array_filter($sample,static function($value){return $value !== null && $value !== '' && (float) $value > 0;}));
        $report=get_user_meta(get_current_user_id(),OWWC_User_State::key('owwc_guide_report'),true);
        $valid=is_array($report) && ($report['currency'] ?? '') === OWWC_Reports::unit()['currency'] && (int) ($report['decimals'] ?? -1) === (int) OWWC_Reports::unit()['decimals'];
        $review=get_user_meta(get_current_user_id(),OWWC_User_State::key('owwc_guide_review'),true); $review_ok=false;
        if (is_array($review) && ($order=wc_get_order((int) ($review['id'] ?? 0)))) {
            $meta=(array) $order->get_meta('_owwc_overrides',true);
            $review_ok=(int) ($meta['reviewed_by'] ?? 0) === get_current_user_id() && hash_equals(OWWC_Profit_Calculator::review_signature($order),(string) ($review['signature'] ?? '')) && !empty(OWWC_Profit_Calculator::calculate($order)['ready']);
        }
        $checks=[
            'costs'=>[$native && OWWC_Reports::unit()['decimals'] <= 4, $native ? (OWWC_Reports::unit()['decimals'] <= 4 ? __('Native costs enabled; currency precision supported.', 'orderworth') : __('Store currency precision exceeds four decimals.', 'orderworth')) : __('Enable native costs in WooCommerce first.', 'orderworth')],
            'products'=>[$found > 0, $sample ? sprintf(/* translators: 1: report value or label; 2: report value or label. */ __('%1$s of %2$s recently added products/variations have a positive cost. This small sample is not a full catalog check.', 'orderworth'), $found, count($sample)) : __('No supported products sampled yet. Add a known product cost when ready.', 'orderworth')],
            'expenses'=>[!empty($settings['confirmed']), !empty($settings['confirmed']) ? __('Expense assumptions are confirmed. Check them against your records.', 'orderworth') : __('Review your expense assumptions and save the confirmation.', 'orderworth')],
            'report'=>[$valid, $valid ? sprintf(/* translators: 1: report value or label; 2: report value or label; 3: report value or label. */ __('Every batch was processed for your report on %1$s. %2$s orders across %3$s period(s). Run again for current results.', 'orderworth'), wp_date('M j, Y H:i', (int) $report['at']), array_sum(array_column($report['groups'],'total')), count($report['groups'])) : __('No completed report recorded for your account and current currency.', 'orderworth')],
            'review'=>[$review_ok, $review_ok ? __('Your last saved review is unchanged and currently has enough data for an estimate.', 'orderworth') : __('No unchanged, complete review recorded for your account. A review is optional when no order needs one.', 'orderworth')],
        ];
        return apply_filters('owwc_guide_checks', $checks, $report, $valid);
    }
    private static function destination(string $action): string {
        return apply_filters('owwc_guide_destination', OWWC_Admin::url($action === 'report' ? [] : ['view'=>$action]), $action);
    }
    private static function completion(): void {
        echo '<section class="owwc-card owwc-guide-complete" aria-labelledby="owwc-guide-complete-title"><p class="owwc-eyebrow">' . esc_html__('QUICKSTART FINISHED', 'orderworth') . '</p><h2 id="owwc-guide-complete-title">' . esc_html__('Quickstart complete', 'orderworth') . '</h2><p>' . esc_html__('Your lesson progress is saved. You can open your reports now and revisit any lesson later.', 'orderworth') . '</p><p class="description">' . esc_html__('Reading the lessons does not confirm your costs or report accuracy. Review your store checks and any missing data before relying on an estimate.', 'orderworth') . '</p><p><a class="button" href="' . esc_url(OWWC_Admin::url()) . '">' . esc_html__('Open profit overview', 'orderworth') . '</a></p></section>';
        $invited = OWWC_Consent::invitation();
        echo '<section class="owwc-card"><h2>' . esc_html__('Keep learning at your own pace', 'orderworth') . '</h2><p>' . esc_html__('You can replay the quickstart without changing your saved store settings or privacy choices.', 'orderworth') . '</p><div class="owwc-guide-actions">';
        self::button('replay', __('Replay quickstart', 'orderworth'));
        if (!$invited && OWWC_Consent::allowed()) {
            echo '<a class="button" href="' . esc_url(OWWC_Consent::url(true)) . '">' . esc_html__('Review privacy choices', 'orderworth') . '</a>';
        }
        echo '</div></section>';
    }
    public static function page(): void {
        if (!current_user_can('manage_woocommerce')) { return; }
        $lessons=self::lessons(); $ids=array_column($lessons,'id'); $state=self::state();
        // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Read-only lesson navigation; save() independently checks capability and nonce.
        $requested=isset($_GET['lesson']) && is_string($_GET['lesson']) ? sanitize_key(wp_unslash($_GET['lesson'])) : $state['step'];
        // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Read-only selection of the saved completion screen; no consent or progress is changed on GET.
        if (self::completed() && (!isset($_GET['lesson']) || !is_string($_GET['lesson']) || !in_array($requested, $ids, true))) { self::completion(); return; }
        $index=array_search($requested,$ids,true); $index=$index === false ? 0 : $index; $lesson=$lessons[$index]; $checks=self::checks();
        echo ('<section class="owwc-card">' . '<h2>' . esc_html__('Optional quickstart', 'orderworth') . '</h2>' . '<p>' . esc_html__('Follow one lesson at a time, skip ahead or stop whenever you like. Reading a lesson does not change costs, orders or schedules.', 'orderworth') . '</p>' . '<p>' . '<strong>' . esc_html(sprintf(/* translators: 1: report value or label; 2: report value or label. */ __('%1$s of %2$s lessons marked read', 'orderworth'), count(array_intersect($ids,$state['seen'])), count($ids))) . '</strong>' . esc_html__(' · Saved for your account. Store checks below are separate from reading progress.', 'orderworth') . '</p>' . '<div class="owwc-guide-actions">');
        self::button($state['status'] === 'new' ? 'start' : 'resume',$state['status'] === 'new' ? __('Start quickstart', 'orderworth') : __('Resume quickstart', 'orderworth'),'',true);
        self::button('later',__('Not now', 'orderworth'),$lesson['id']); self::button('replay',__('Replay from start', 'orderworth'));
        echo ('</div>' . '</section>' . '<div class="owwc-guide-layout">' . '<nav class="owwc-card owwc-guide-nav" aria-label="' . esc_attr__('Quickstart lessons', 'orderworth') . '">');
        foreach ($lessons as $i=>$item) { echo '<a href="' . esc_url(OWWC_Admin::url(['view'=>'tutorial','lesson'=>$item['id']])) . '"' . ($i === $index ? ' aria-current="step"' : '') . '>' . esc_html(($i+1) . '. ' . $item['title']) . ($item['edition'] === 'pro' ? esc_html__(' · Pro', 'orderworth') : '') . (in_array($item['id'],$state['seen'],true) ? esc_html__(' · Read', 'orderworth') : '') . '</a>'; }
        echo '</nav><article class="owwc-card"><p class="owwc-eyebrow">' . ($lesson['edition'] === 'pro' ? esc_html__('PRO LESSON', 'orderworth') : esc_html__('FREE + PRO', 'orderworth')) . ' · ' . (int) ($index+1) . ' / ' . count($ids) . '</p><h2>' . esc_html($lesson['title']) . '</h2><p>' . esc_html($lesson['intro']) . '</p><ol class="owwc-guide-steps">';
        foreach ($lesson['steps'] as $step) { echo '<li>' . esc_html($step) . '</li>'; }
        echo '</ol><p class="owwc-warning">' . esc_html($lesson['note']) . '</p>';
        if (isset($checks[$lesson['id']])) { $check=$checks[$lesson['id']]; echo '<p class="owwc-guide-check"><strong>' . ($check[0] ? esc_html__('Observed in your store: ', 'orderworth') : esc_html__('Check your setup: ', 'orderworth')) . '</strong>' . esc_html($check[1]) . '</p>'; }
        if (isset($lesson['example'])) { self::example($lesson['example']); }
        echo '<p><a class="button" href="' . esc_url(self::destination($lesson['action'])) . '">' . esc_html($lesson['actionLabel']) . '</a></p>';
        if (isset($lesson['reference'])) { echo ('<p>' . '<a href="' . esc_url($lesson['reference']) . '" target="_blank" rel="noopener noreferrer">' . esc_html__('Official WooCommerce cost setup reference', 'orderworth') . '</a>' . '</p>'); }
        echo '<div class="owwc-guide-actions">';
        if ($index > 0) { echo ('<a class="button" href="' . esc_url(OWWC_Admin::url(['view'=>'tutorial','lesson'=>$ids[$index-1]])) . '">' . esc_html__('Previous lesson', 'orderworth') . '</a>'); }
        $last_unread = !array_diff($ids, array_merge($state['seen'], [$lesson['id']]));
        self::button('next',$last_unread ? __('Finish quickstart', 'orderworth') : __('Mark read & continue', 'orderworth'),$lesson['id'],true);
        echo ('</div>' . '<p class="description">' . esc_html__('Replay resets your lesson progress only. Your saved store data stays in place. ', 'orderworth') . '<a href="' . esc_url(OWWC_Admin::url(['view'=>'guide'])) . '">' . esc_html__('Calculation reference and troubleshooting', 'orderworth') . '</a>' . '</p>' . '</article>' . '</div>');
    }
    private static function example(string $name): void {
        echo ('<details class="owwc-guide-example">' . '<summary>' . esc_html__('See an annotated example · sample data', 'orderworth') . '</summary>');
        if ($name === 'coverage') { echo ('<p>' . '<strong>' . esc_html__('18 of 20 orders included', 'orderworth') . '</strong>' . '</p>' . '<ol>' . '<li>' . esc_html__('The displayed profit covers 18 orders with enough data.', 'orderworth') . '</li>' . '<li>' . esc_html__('The other 2 need review and are excluded.', 'orderworth') . '</li>' . '<li>' . esc_html__('Review missing data, then rerun the report. Do not assume the missing orders earned zero.', 'orderworth') . '</li>' . '</ol>'); }
        elseif ($name === 'expenses') { echo ('<p>' . esc_html__('Example: customer pays 8 for shipping; you pay the carrier 6 and spend 1 on packaging.', 'orderworth') . '</p>' . '<ol>' . '<li>' . esc_html__('The customer\'s 8 is already part of revenue.', 'orderworth') . '</li>' . '<li>' . esc_html__('Enter 6 as your shipping expense.', 'orderworth') . '</li>' . '<li>' . esc_html__('Enter 1 as your packaging expense.', 'orderworth') . '</li>' . '</ol>'); }
        else { echo ('<p>' . esc_html__('Example: original product cost 40; returned stock recovers 20.', 'orderworth') . '</p>' . '<ol>' . '<li>' . esc_html__('Confirm original product costs of 40.', 'orderworth') . '</li>' . '<li>' . esc_html__('Confirm recovered cost of 20 only if that stock is recoverable.', 'orderworth') . '</li>' . '<li>' . esc_html__('The net product-cost deduction is 20. Review retained payment and shipping expenses separately.', 'orderworth') . '</li>' . '</ol>'); }
        echo ('<p class="description">' . esc_html__('Illustrative values only; this example creates no products or orders.', 'orderworth') . '</p>' . '</details>');
    }
}