<?php

declare(strict_types=1);

if (!defined('ABSPATH')) {
    exit;
}

final class TheDotDevAgenticBridge_Onboarding_Wizard
{
    public const MAX_SHORT_CHARS = 120;

    public const MAX_LONG_CHARS = 500;

    public const MAX_QUESTIONS = 10;

    public const NONCE_ACTION = 'thedotdev_agentic_bridge_onboarding_complete';

    public const POST_ACTION = 'thedotdev_agentic_bridge_complete_onboarding';

    public const LEGACY_POST_ACTION = 'thedotdev_agentic_bridge_onboarding_complete';

    public const TRANSIENT_KEY = 'thedotdev_agentic_bridge_onboarding_complete';

    public static function init(): void
    {
        add_action('admin_menu', [self::class, 'add_admin_page']);
        add_action('admin_post_' . self::POST_ACTION, [self::class, 'handle_form_submission']);
        add_action('admin_post_' . self::LEGACY_POST_ACTION, [self::class, 'handle_form_submission']);
    }

    public static function add_admin_page(): void
    {
        $setup_label = self::is_setup_confirmed()
            ? __('Setup guide', 'agentic-bridge')
            : __('Quick Start', 'agentic-bridge');
        TheDotDevAgenticBridge_Admin::register_hidden_submenu_page(
            $setup_label,
            $setup_label,
            TheDotDevAgenticBridge_Admin::SETUP_WIZARD_SLUG,
            [self::class, 'render_wizard']
        );
    }

    public static function render_wizard(): void
    {
        if (!current_user_can('manage_options')) {
            wp_die(esc_html__('You do not have sufficient permissions to access this page.', 'agentic-bridge'));
        }

        $onboarding_complete = self::is_setup_confirmed();
        $scan = TheDotDevAgenticBridge_Readiness_Store::latest();
        $scan = is_array($scan) ? $scan : [];
        $findings = is_array($scan['findings'] ?? null) ? $scan['findings'] : [];
        $onboarding = self::state();
        $onboarding_step = self::resolved_step($onboarding, $scan);
        $eligible_content = TheDotDevAgenticBridge_Content_Policy::eligible_content_items();
        $suggested_questions = self::suggested_questions(is_array($onboarding['business'] ?? null) ? $onboarding['business'] : []);
        // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Read-only, sanitized flash notice; no state change.
        $thedotdev_agentic_bridge_notice = isset($_GET['thedotdev_agentic_bridge_notice']) ? sanitize_text_field(wp_unslash((string) $_GET['thedotdev_agentic_bridge_notice'])) : '';
        // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- Read-only, allowlisted notice type; no state change.
        $thedotdev_agentic_bridge_notice_type = isset($_GET['thedotdev_agentic_bridge_notice_type']) ? sanitize_key((string) wp_unslash($_GET['thedotdev_agentic_bridge_notice_type'])) : 'success';

        if (TheDotDevAgenticBridge_V2_Presentation::is_enabled()) {
            TheDotDevAgenticBridge_V2_Presentation::render_setup(get_defined_vars());

            return;
        }

        include THEDOTDEV_AGENTIC_BRIDGE_PLUGIN_DIR . 'views/onboarding-wizard.php';
    }

    public static function handle_form_submission(): void
    {
        self::process_submission(true);
    }

    public static function is_setup_confirmed(): bool
    {
        if (TheDotDevAgenticBridge_Storage::is_onboarding_complete()) {
            return true;
        }

        return (bool) get_transient(self::TRANSIENT_KEY);
    }

    /** @return array<string, mixed> */
    public static function state(): array
    {
        $settings = TheDotDevAgenticBridge_Storage::get();
        $stored = is_array($settings['onboarding'] ?? null) ? $settings['onboarding'] : [];

        return array_merge([
            'status' => 'not_started',
            'step' => 1,
            'business' => [],
            'questions' => [],
            'questionsReviewed' => false,
            'contentReviewedAt' => '',
            'completedAt' => '',
        ], $stored);
    }

    /** @param array<string, mixed> $state @param array<string, mixed> $scan */
    public static function resolved_step(array $state, array $scan): int
    {
        $step = max(1, min(6, (int) ($state['step'] ?? 1)));
        if ($step === 5 && isset($scan['score'])) {
            return 6;
        }

        return $step;
    }

    /** @param array<string, mixed> $raw @return array<string, string> */
    public static function sanitize_business(array $raw): array
    {
        $type = sanitize_key((string) ($raw['site_type'] ?? ''));
        $representation = sanitize_key((string) ($raw['representation'] ?? ''));

        return [
            'site_type' => in_array($type, ['services', 'store', 'publisher', 'nonprofit', 'portfolio', 'other'], true) ? $type : 'other',
            'representation' => in_array($representation, ['organisation', 'person'], true) ? $representation : 'organisation',
            'brand_name' => self::bounded_text((string) ($raw['brand_name'] ?? ''), self::MAX_SHORT_CHARS),
            'core_offerings' => self::bounded_text((string) ($raw['core_offerings'] ?? ''), self::MAX_LONG_CHARS),
            'service_area' => self::bounded_text((string) ($raw['service_area'] ?? ''), self::MAX_LONG_CHARS),
            'availability' => self::bounded_text((string) ($raw['availability'] ?? ''), self::MAX_LONG_CHARS),
            'primary_action' => self::bounded_text((string) ($raw['primary_action'] ?? ''), self::MAX_SHORT_CHARS),
        ];
    }

    /** @param array<string, mixed> $business @return list<string> */
    public static function suggested_questions(array $business): array
    {
        $brand = self::bounded_text((string) ($business['brand_name'] ?? ''), self::MAX_SHORT_CHARS);
        if ($brand === '') {
            $brand = self::bounded_text((string) get_bloginfo('name'), self::MAX_SHORT_CHARS);
        }
        $subject = $brand !== '' ? $brand : __('this business', 'agentic-bridge');
        $questions = [
            /* translators: %s: business or site name. */
            sprintf(__('What does %s offer?', 'agentic-bridge'), $subject),
            /* translators: %s: business or site name. */
            sprintf(__('Where does %s provide services or deliver?', 'agentic-bridge'), $subject),
            /* translators: %s: business or site name. */
            sprintf(__('When is %s available?', 'agentic-bridge'), $subject),
            /* translators: %s: business or site name. */
            sprintf(__('How can a customer contact or book with %s?', 'agentic-bridge'), $subject),
            /* translators: %s: business or site name. */
            sprintf(__('Which policies should customers know before choosing %s?', 'agentic-bridge'), $subject),
        ];

        return array_values(array_unique(array_map(static fn (string $question): string => self::bounded_text($question, 240), $questions)));
    }

    /** @return list<string> */
    public static function sanitize_questions(string $raw): array
    {
        $questions = [];
        foreach (preg_split('/\R/u', $raw) ?: [] as $line) {
            $question = self::bounded_text((string) $line, 240);
            if ($question === '' || in_array($question, $questions, true)) {
                continue;
            }
            $questions[] = $question;
            if (count($questions) >= self::MAX_QUESTIONS) {
                break;
            }
        }

        return $questions;
    }

    private static function process_submission(bool $strict_admin_post): void
    {
        if (!current_user_can('manage_options')) {
            self::redirect_setup(
                __('You do not have permission to confirm setup.', 'agentic-bridge'),
                'error'
            );
        }
        // phpcs:ignore WordPress.Security.NonceVerification.Missing,WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- verified via wp_verify_nonce below; sanitized immediately.
        $raw_nonce = isset($_POST['_wpnonce']) ? wp_unslash($_POST['_wpnonce']) : '';
        $nonce = is_string($raw_nonce) ? sanitize_text_field($raw_nonce) : '';
        if ($nonce === '' || !wp_verify_nonce($nonce, self::NONCE_ACTION)) {
            self::redirect_setup(
                __('Setup could not be confirmed. Refresh the page and try again.', 'agentic-bridge'),
                'error'
            );
        }

        // phpcs:ignore WordPress.Security.NonceVerification.Missing -- Verified immediately above.
        $operation = sanitize_key((string) wp_unslash($_POST['onboarding_operation'] ?? 'dismiss'));
        $state = self::state();

        if ($operation === 'start') {
            self::save_state(array_merge($state, ['status' => 'in_progress', 'step' => 2]));
            self::redirect_setup(__('Quick Start started. Nothing has left this site.', 'agentic-bridge'), 'success');
        }
        if ($operation === 'save_business') {
            // phpcs:ignore WordPress.Security.NonceVerification.Missing,WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- Verified above; the bounded business array is sanitized by sanitize_business() below.
            $raw_business = isset($_POST['business']) && is_array($_POST['business']) ? wp_unslash($_POST['business']) : [];
            self::save_state(array_merge($state, [
                'status' => 'in_progress',
                'step' => 3,
                'business' => self::sanitize_business($raw_business),
            ]));
            self::redirect_setup(__('Business basics saved locally. Review the suggested customer questions next.', 'agentic-bridge'), 'success');
        }
        if ($operation === 'save_questions') {
            // phpcs:ignore WordPress.Security.NonceVerification.Missing,WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- Verified above; the text is sanitized by sanitize_questions() below.
            $raw_questions = (string) wp_unslash($_POST['questions'] ?? '');
            self::save_state(array_merge($state, [
                'status' => 'in_progress',
                'step' => 4,
                'questions' => self::sanitize_questions($raw_questions),
                'questionsReviewed' => false,
            ]));
            self::redirect_setup(__('Question drafts saved locally. They are not marked reviewed or published.', 'agentic-bridge'), 'success');
        }
        if ($operation === 'confirm_content') {
            self::save_state(array_merge($state, [
                'status' => 'in_progress',
                'step' => 5,
                'contentReviewedAt' => gmdate('c'),
            ]));
            self::redirect_setup(__('Public content scope reviewed. Run the first local check when ready.', 'agentic-bridge'), 'success');
        }
        if ($operation === 'restart') {
            TheDotDevAgenticBridge_Storage::update(['onboarding_complete' => false]);
            self::save_state(array_merge($state, ['status' => 'in_progress', 'step' => 1]));
            self::redirect_setup(__('Quick Start reopened. Your saved local answers are still available.', 'agentic-bridge'), 'success');
        }

        $status = $operation === 'finish' ? 'complete' : 'skipped';
        self::save_state(array_merge($state, [
            'status' => $status,
            'step' => $operation === 'finish' ? 6 : max(1, (int) ($state['step'] ?? 1)),
            'completedAt' => $operation === 'finish' ? gmdate('c') : '',
        ]));
        if (!TheDotDevAgenticBridge_Storage::mark_onboarding_complete()) {
            self::redirect_setup(__('Setup could not be saved. Try again or contact your host if this keeps happening.', 'agentic-bridge'), 'error');
        }
        set_transient(self::TRANSIENT_KEY, true, 7 * 24 * HOUR_IN_SECONDS);
        self::redirect_setup(
            $operation === 'finish'
                ? __('Quick Start complete. Your next improvement is ready to review.', 'agentic-bridge')
                : __('Quick Start skipped. You can reopen it any time; local features remain available.', 'agentic-bridge'),
            'success'
        );
    }

    /** @param array<string, mixed> $state */
    private static function save_state(array $state): void
    {
        TheDotDevAgenticBridge_Storage::update(['onboarding' => $state]);
    }

    private static function bounded_text(string $value, int $limit): string
    {
        $value = trim((string) preg_replace('/\s+/u', ' ', wp_strip_all_tags($value, true)));
        if ($value === '') {
            return '';
        }
        if (function_exists('mb_substr')) {
            return mb_substr($value, 0, $limit);
        }

        return substr($value, 0, $limit);
    }

    private static function redirect_setup(string $message, string $type): void
    {
        wp_safe_redirect(add_query_arg(
            [
                'thedotdev_agentic_bridge_notice' => $message,
                'thedotdev_agentic_bridge_notice_type' => $type === 'error' ? 'error' : 'success',
            ],
            TheDotDevAgenticBridge_Admin::setup_url()
        ));
        exit;
    }
}