<?php

declare(strict_types=1);

namespace AetosSeo\Core;

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

class Settings
{
    public const OPTION_KEY = 'aetos_seo_settings';
    public const CRAWL_STATE_OPTION = 'aetos_seo_crawl_state';
    public const REPORTS_INDEX_OPTION = 'aetos_seo_reports_index';

    /**
     * Default settings.
     *
     * @return array<string,mixed>
     */
    public static function defaults(): array
    {

        return [
            'scan_mode' => 'full',
            // v2.3.0 — email summary on audit completion (off by default).
            'notifications' => [
                'email_on_complete' => 0,
                'email_recipient'   => '', // empty = use site admin_email
            ],
            'scan_limits' => [
                'max_files' => 5000,
                // 0 = skip scanning uploads directory in FS collector (recommended on shared hosting).
                'fs_include_uploads' => 0,
                'max_seconds' => 20,
                'max_seconds_per_batch' => 5,
                // Sensible non-zero defaults so a fresh install does not appear
                // to "freeze" on large sites. Every value is user-editable in
                // Settings → Scan Limits, and 0 means "no limit" and is honored.
                'full_scan_max_pages' => 1000,
                // How many discovered pages the audit analyzes. The default
                // keeps the first scan snappy; the site owner can raise it to
                // any value (0 = analyze every page discovered).
                'audit_analysis_max_pages' => 50,
                'sample_scan_pages' => 10,
                // v3.3.40 — lowered to 200 so the build-inventory phase
                // terminates in ~5-7 minutes for typical sites. Raise it in
                // Settings → Scan Limits for a deeper crawl (0 = no limit).
                'crawl_max_urls' => 200,
                'crawl_queue_cap' => 50000,
                'crawl_per_batch' => 2,
                'crawl_delay_ms' => 1500,
                'broken_links_per_page' => 15,
                'internal_links_extract_limit' => 200,
                'exclude_global_nav_links' => 1,
            ],
            'data_sharing' => [
                'summaries_only' => 1,
                'allow_snippets' => 0,
                'max_snippet_chars' => 1200,
            ],
            'logs' => [
                // Preferred access-log copy path (for crawler behavior analysis).
                'access_path' => '',
                // Optional PHP/debug log path fallback.
                'custom_path' => '',
                'max_lines' => 500,
            ],
            'ui' => [
                // v1.0.90: advanced tools menu visible by default so the Crawl
                // tool is reachable out of the box. The toggle can still be
                // turned off in Settings to declutter the menu.
                'show_advanced_tools_menu' => 1,
                // v3.0.0: locale override. 'auto' = follow WordPress site
                // locale (is_rtl() → Arabic; otherwise English). 'ar' / 'en'
                // force the plugin admin UI to that language regardless of
                // what WordPress is set to. Used by Utils\I18n::tr().
                'admin_locale' => 'auto',
            ],
        ];
    }

    /**
     * @return array<string,mixed>
     */
    public static function get(): array
    {
        $settings = get_option(self::OPTION_KEY);
        if (!is_array($settings)) {
            return self::defaults();
        }

        $merged = self::merge_recursive(self::defaults(), $settings);
        return self::normalize_settings($merged);
    }

    /**
     * @param array<string,mixed> $new
     */
    public static function update(array $new): bool
    {
        $merged = self::merge_recursive(self::defaults(), $new);
        $normalized = self::normalize_settings($merged);
        return update_option(self::OPTION_KEY, $normalized, false);
    }

    /**
     * @param array<string,mixed> $settings
     * @return array<string,mixed>
     */
    private static function normalize_settings(array $settings): array
    {
        if (!isset($settings['scan_mode']) || !in_array((string) $settings['scan_mode'], ['full', 'sample'], true)) {
            $settings['scan_mode'] = 'full';
        }

        if (!isset($settings['scan_limits']) || !is_array($settings['scan_limits'])) {
            $settings['scan_limits'] = self::defaults()['scan_limits'];
        }
        $settings['scan_limits'] = self::normalize_scan_limits($settings['scan_limits']);


        if (!isset($settings['data_sharing']) || !is_array($settings['data_sharing'])) {
            $settings['data_sharing'] = self::defaults()['data_sharing'];
        }
        $settings['data_sharing'] = self::merge_recursive(self::defaults()['data_sharing'], $settings['data_sharing']);
        $settings['data_sharing']['summaries_only'] = !empty($settings['data_sharing']['summaries_only']) ? 1 : 0;
        $settings['data_sharing']['allow_snippets'] = !empty($settings['data_sharing']['allow_snippets']) ? 1 : 0;
        $settings['data_sharing']['max_snippet_chars'] = max(200, min(1200, (int) ($settings['data_sharing']['max_snippet_chars'] ?? 1200)));

        if (!isset($settings['logs']) || !is_array($settings['logs'])) {
            $settings['logs'] = self::defaults()['logs'];
        }
        $settings['logs'] = self::merge_recursive(self::defaults()['logs'], $settings['logs']);
        $settings['logs']['access_path'] = isset($settings['logs']['access_path']) ? (string) $settings['logs']['access_path'] : '';
        $settings['logs']['custom_path'] = isset($settings['logs']['custom_path']) ? (string) $settings['logs']['custom_path'] : '';
        $settings['logs']['max_lines'] = max(50, min(5000, (int) ($settings['logs']['max_lines'] ?? 500)));

        // v1.0.58: ui section
        if (!isset($settings['ui']) || !is_array($settings['ui'])) {
            $settings['ui'] = self::defaults()['ui'];
        }
        $settings['ui'] = self::merge_recursive(self::defaults()['ui'], $settings['ui']);
        $settings['ui']['show_advanced_tools_menu'] = !empty($settings['ui']['show_advanced_tools_menu']) ? 1 : 0;

        $settings = FeatureGate::apply_settings_limits($settings);

        return $settings;
    }

    /**
     * @param array<string,mixed> $limits
     * @return array<string,int>
     */
    private static function normalize_scan_limits(array $limits): array
    {
        $defaults = self::defaults()['scan_limits'];
        $limits = self::merge_recursive($defaults, $limits);

        // 0 means "no limit" for every page-count field and is preserved as 0
        // (honored by the crawler and the auditor). The non-zero defaults keep
        // a fresh install snappy; the site owner can set any value, including 0
        // for a full-site scan. Depth is never gated by edition.
        $full_scan_max_pages = isset($limits['full_scan_max_pages']) ? (int) $limits['full_scan_max_pages'] : 1000;
        $audit_analysis_max_pages = isset($limits['audit_analysis_max_pages']) ? (int) $limits['audit_analysis_max_pages'] : 50;
        $crawl_max_urls = isset($limits['crawl_max_urls']) ? (int) $limits['crawl_max_urls'] : 200;

        return [
            'max_files' => max(200, min(50000, (int) ($limits['max_files'] ?? 5000))),
            'fs_include_uploads' => !empty($limits['fs_include_uploads']) ? 1 : 0,
            'max_seconds' => max(5, min(600, (int) ($limits['max_seconds'] ?? 20))),
            'max_seconds_per_batch' => max(2, min(30, (int) ($limits['max_seconds_per_batch'] ?? 5))),
            'full_scan_max_pages' => max(0, min(500000, $full_scan_max_pages)),
            'audit_analysis_max_pages' => max(0, min(500000, $audit_analysis_max_pages)),
            'sample_scan_pages' => max(3, min(1000, (int) ($limits['sample_scan_pages'] ?? ($limits['sample_pages'] ?? 10)))),
            'crawl_max_urls' => max(0, min(500000, $crawl_max_urls)),
            'crawl_queue_cap' => max(500, min(200000, (int) ($limits['crawl_queue_cap'] ?? 50000))),
            'crawl_per_batch' => max(1, min(20, (int) ($limits['crawl_per_batch'] ?? 2))),
            'crawl_delay_ms' => max(500, min(30000, (int) ($limits['crawl_delay_ms'] ?? 1500))),
            'broken_links_per_page' => max(5, min(100, (int) ($limits['broken_links_per_page'] ?? 15))),
            'internal_links_extract_limit' => max(20, min(5000, (int) ($limits['internal_links_extract_limit'] ?? 200))),
            'exclude_global_nav_links' => !empty($limits['exclude_global_nav_links']) ? 1 : 0,
        ];
    }


    public static function is_safe_mode(): bool
    {
        $s = self::get();
        return !empty($s['safe_mode']);
    }

    /**
     * Advanced tools menu visibility (the Crawl tool).
     *
     * v1.0.58: now reads from a setting too, so non-developers can flip it from
     * the Settings UI without writing PHP filter code.
     */
    public static function is_advanced_tools_enabled(): bool
    {
        $s = self::get();
        $from_setting = !empty($s['ui']['show_advanced_tools_menu']);

        /**
         * Filter override (still respected for developers who want to force it).
         *
         * @param bool $enabled
         * @param array<string,mixed> $settings
         */
        return (bool) apply_filters('aetos_seo_enable_advanced_tools_menu', $from_setting, $s);
    }

    public static function ensure_upload_dirs(): void
    {
        $upload = wp_upload_dir(null, false);
        $base = trailingslashit($upload['basedir']) . 'aetos-seo';
        $dirs = [
            $base,
            $base . '/reports',
            $base . '/cache',
            $base . '/logs',
        ];
        foreach ($dirs as $dir) {
            if (!is_dir($dir)) {
                wp_mkdir_p($dir);
            }
        }

        foreach ($dirs as $dir) {
            // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_is_writable -- Checking writability of plugin-owned upload subdir before placing index/htaccess guards; WP_Filesystem here would require admin credentials during a regular activation.
            if (!is_dir($dir) || !is_writable($dir)) {
                continue;
            }

            $index_html = $dir . '/index.html';
            if (!file_exists($index_html)) {
                @file_put_contents($index_html, '');
            }

            $index_php = $dir . '/index.php';
            if (!file_exists($index_php)) {
                @file_put_contents($index_php, "<?php\n// Silence is golden.\n");
            }

            $htaccess = $dir . '/.htaccess';
            if (!file_exists($htaccess)) {
                @file_put_contents($htaccess, "<IfModule mod_authz_core.c>\nRequire all denied\n</IfModule>\n<IfModule !mod_authz_core.c>\nDeny from all\n</IfModule>\n");
            }

            $web_config = $dir . '/web.config';
            if (!file_exists($web_config)) {
                @file_put_contents($web_config, "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<configuration>\n  <system.webServer>\n    <authorization>\n      <deny users=\"*\" />\n    </authorization>\n  </system.webServer>\n</configuration>\n");
            }

            // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_chmod -- Hardening permissions on plugin-owned upload subdir to 0700 right after creation; WP_Filesystem does not expose chmod for this use.
            @chmod($dir, 0700);
        }
    }

    public static function delete_upload_dirs(): void
    {
        $upload = wp_upload_dir(null, false);
        $base = trailingslashit($upload['basedir']) . 'aetos-seo';
        self::rmdir_recursive($base);
    }

    private static function rmdir_recursive(string $dir): void
    {
        if (!is_dir($dir)) {
            return;
        }
        $items = scandir($dir);
        if (!is_array($items)) {
            return;
        }
        foreach ($items as $item) {
            if ($item === '.' || $item === '..') {
                continue;
            }
            $path = $dir . DIRECTORY_SEPARATOR . $item;
            if (is_dir($path)) {
                self::rmdir_recursive($path);
            } else {
                wp_delete_file($path);
            }
        }
        // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_rmdir -- Removing empty plugin-owned upload subdir; no FS credentials available in destructor context.
        @rmdir($dir);
    }

    /**
     * Merge recursively with scalar overwrite.
     *
     * @param array<string,mixed> $base
     * @param array<string,mixed> $override
     * @return array<string,mixed>
     */
    private static function merge_recursive(array $base, array $override): array
    {
        foreach ($override as $k => $v) {
            if (is_array($v) && isset($base[$k]) && is_array($base[$k])) {
                /** @var array<string,mixed> $baseK */
                $baseK = $base[$k];
                /** @var array<string,mixed> $v */
                $base[$k] = self::merge_recursive($baseK, $v);
            } else {
                $base[$k] = $v;
            }
        }
        return $base;
    }
}