<?php
/**
 * Settings storage.
 *
 * @package KarmaDocs
 */

namespace KarmaDocs;

defined( 'ABSPATH' ) || exit;

/**
 * Typed option wrapper for `kdocs_settings`.
 */
class Settings {

	const OPTION = 'kdocs_settings';

	/**
	 * Renamed settings: old key => [ new key, callable mapping the old value or null ].
	 * Applied to stored settings (migration) and to imported settings files.
	 */
	const RENAMED = array(
		// 1.0: "Hide on documentation pages" became the "Show on" choice.
		'widget_exclude_docs' => array( 'widget_display', array( __CLASS__, 'map_widget_exclude' ) ),
	);

	/**
	 * Runtime cache.
	 *
	 * @var array|null
	 */
	private static $cache = null;

	/**
	 * Saved settings (without preview overrides).
	 *
	 * @var array|null
	 */
	private static $saved = null;

	/**
	 * Settings the design studio previews and presets change.
	 */
	const DESIGN_KEYS = array(
		'primary_color',
		'font_family',
		'radius',
		'container_width',
		'columns',
		'home_layout',
		'article_width',
		'color_scheme',
		'card_thumbnails',
		'show_sidebar',
		'sidebar_style',
		'docs_shell',
		'docs_logo',
		'docs_logo_dark',
		'docs_favicon',
		'docs_header_links',
		'design_preset',
		'use_inter_font',
	);

	/**
	 * Settings limited to a fixed list of values (the first is the fallback).
	 */
	const CHOICES = array(
		'home_layout'        => array( 'cards', 'list', 'minimal', 'boxed' ),
		'color_scheme'       => array( 'toggle', 'light', 'dark' ),
		'font_family'        => array( 'inter', 'system', 'serif' ),
		'article_width'      => array( 'normal', 'wide' ),
		'sidebar_style'      => array( 'classic', 'lined', 'boxed', 'filled', 'minimal', 'accordion' ),
		'docs_shell'         => array( 'theme', 'app' ),
		'report_frequency'   => array( 'off', 'weekly', 'monthly' ),
		'embedding_provider' => array( 'openai', 'google', 'voyage' ),
	);

	/**
	 * Default values. Types here drive sanitization.
	 *
	 * @return array
	 */
	public static function defaults() {
		return array(
			// General.
			'docs_slug'               => 'docs',
			'category_base'           => 'category',
			'home_title'              => __( 'How can we help?', 'karma-docs' ),
			'home_subtitle'           => __( 'Search our knowledge base or browse the topics below.', 'karma-docs' ),
			'single_kb_redirect'      => true,
			'articles_per_section'    => 5,
			'show_popular'            => true,
			'contact_enabled'         => true,
			'contact_title'           => __( 'Still need help?', 'karma-docs' ),
			'contact_text'            => __( 'Can’t find what you’re looking for? Our team is happy to help.', 'karma-docs' ),
			'contact_label'           => __( 'Contact support', 'karma-docs' ),
			'contact_url'             => '',
			'enable_comments'         => false,

			// Appearance.
			'primary_color'           => '#6d5efc',
			'home_layout'             => 'cards',   // cards | list | minimal (pro) | boxed (pro).
			'columns'                 => 3,
			'container_width'         => 1240,
			'color_scheme'            => 'toggle',  // toggle | light | dark.
			'show_sidebar'            => true,
			'show_toc'                => true,
			'toc_depth'               => 3,
			'use_inter_font'          => true,
			'font_family'             => 'inter',   // inter | system | serif.
			'radius'                  => 12,
			'article_width'           => 'normal',  // normal | wide.
			'sidebar_style'           => 'classic', // classic | lined | boxed | filled | minimal | accordion.
			'card_thumbnails'         => false,
			'design_preset'           => '',

			// Docs app mode: own slim header instead of the theme's.
			'docs_shell'              => 'theme',   // theme | app.
			'docs_logo'               => 0,
			'docs_logo_dark'          => 0,
			'docs_favicon'            => 0,
			'docs_header_links'       => '',

			// Article features.
			'enable_search'           => true,
			'search_shortcut'         => true,
			'enable_feedback'         => true,
			'feedback_reasons'        => true,

			// Analytics.
			'analytics_count_editors' => false,
			'analytics_retention'     => 90,
			'impact_ticket_rate'      => 20,     // % of self-service sessions that would have become a ticket.
			'impact_ticket_cost'      => 15,
			'impact_currency'         => '$',
			'report_frequency'        => 'off',  // off | weekly | monthly (Pro).
			'report_recipients'       => '',
			'report_kb'               => 0,
			'show_reading_time'       => true,
			'show_last_updated'       => true,
			'show_print'              => true,
			'show_breadcrumbs'        => true,
			'show_prev_next'          => true,
			'show_related'            => true,
			'show_author'             => false,
			'copy_code'               => true,
			'anchor_links'            => true,
			'enable_schema'           => true,

			// Pro.
			'feedback_form'           => true,
			'notify_email'            => '',
			'feedback_retention'      => 0,
			'notify_negative'         => true,
			'notify_digest'           => true,
			'widget_enabled'          => false,
			'widget_position'         => 'right',
			'widget_title'            => __( 'Need help?', 'karma-docs' ),
			'widget_kb'               => 0,
			'widget_contact_url'      => '',
			'widget_display'          => 'everywhere', // everywhere | docs | not_docs.
			'widget_greeting'         => __( 'Search our docs or ask a question.', 'karma-docs' ),
			'review_interval'         => 180,
			'white_label_name'        => '',
			'custom_css'              => '',

			// Content blocks.
			'faq_schema'              => true,

			// Data.
			'delete_data'             => false,

			// Pro: PDF export.
			'pdf_enabled'             => true,

			// Pro: versions.
			'version_banner'          => true,

			// Pro: contributors & approval workflow.
			'workflow_enabled'        => false,
			'workflow_notify'         => true,

			// Pro: integrations.
			'webhook_url'             => '',
			'webhook_secret'          => '',
			'slack_webhook_url'       => '',
			'integration_events'      => 'feedback.negative,feedback.message,article.published,search.no_results,review.submitted',

			// Pro: search provider.
			'search_provider'         => 'wordpress', // wordpress | algolia.
			'algolia_app_id'          => '',
			'algolia_search_key'      => '',
			'algolia_admin_key'       => '',
			'algolia_index'           => 'karma_docs',

			// Pro: AI.
			'ai_enabled'              => false,
			'ai_provider'             => 'anthropic', // anthropic | openai | google.
			'ai_key_anthropic'        => '',
			'ai_key_openai'           => '',
			'ai_key_google'           => '',
			'ai_model'                => '',
			'ai_name'                 => __( 'Docs AI', 'karma-docs' ),
			'ai_in_search'            => true,
			'ai_in_widget'            => true,
			'ai_writer'               => true,
			'ai_rate_limit'           => 20,
			'ai_instructions'         => '',
			'ai_budget'               => 0,
			'summary_show'            => true,
			'summary_auto'            => false,
			'summary_open'            => true,
			'summary_min_words'       => 250,
			'summary_approved_only'   => false,
			'mermaid'                 => false,
			'llms_txt'                => true,
			'slack_digest'            => false,
			'forward_ga4'             => false,
			'forward_plausible'       => false,
			'forward_matomo'          => false,
			'cors_origins'            => '',
			'slack_signing_secret'    => '',
			'discord_public_key'      => '',
			'chat_ai'                 => true,
			'share_images'            => true,
			'semantic_search'         => false,
			'embedding_provider'      => 'openai',
			'ai_key_voyage'           => '',
			'reader_memory'           => true,
		);
	}

	/**
	 * Settings that hold credentials: never sent back to the browser in clear text.
	 *
	 * @return string[]
	 */
	public static function secret_keys() {
		return array( 'ai_key_anthropic', 'ai_key_openai', 'ai_key_google', 'algolia_admin_key', 'webhook_secret', 'slack_signing_secret', 'ai_key_voyage' );
	}

	/**
	 * Masks a secret for display (keeps the last 4 characters).
	 *
	 * @param string $value Secret.
	 * @return string
	 */
	public static function mask( $value ) {
		$value = (string) $value;
		if ( '' === $value ) {
			return '';
		}
		return str_repeat( '•', 8 ) . substr( $value, -4 );
	}

	/**
	 * Settings safe to expose to the admin app (secrets masked).
	 *
	 * @return array
	 */
	public static function for_client() {
		$all = self::all();
		foreach ( self::secret_keys() as $key ) {
			$all[ $key ] = self::mask( $all[ $key ] );
		}
		return $all;
	}

	/**
	 * All settings merged with defaults.
	 *
	 * @return array
	 */
	public static function all() {
		if ( null === self::$cache ) {
			$all = array_merge( self::saved(), self::preview() );
			// A preview request can't be recognised before the user is known: don't cache yet.
			if ( ! empty( $_GET['kdocs_preview'] ) && ! did_action( 'set_current_user' ) ) { // phpcs:ignore WordPress.Security.NonceVerification
				return $all;
			}
			self::$cache = $all;
		}
		return self::$cache;
	}

	/**
	 * Saved settings merged with defaults (never the preview draft).
	 *
	 * @return array
	 */
	public static function saved() {
		if ( null === self::$saved ) {
			$saved       = get_option( self::OPTION, array() );
			self::$saved = wp_parse_args( is_array( $saved ) ? $saved : array(), self::defaults() );
		}
		return self::$saved;
	}

	/**
	 * Design studio: unsaved design values shown only to the admin who is
	 * previewing them (?kdocs_preview=1 in the studio's preview frame).
	 *
	 * @return array
	 */
	private static function preview() {
		if ( empty( $_GET['kdocs_preview'] ) || ! did_action( 'set_current_user' ) || ! current_user_can( Capabilities::SETTINGS ) ) { // phpcs:ignore WordPress.Security.NonceVerification
			return array();
		}
		$draft = get_transient( self::preview_key() );
		return is_array( $draft ) ? array_intersect_key( $draft, array_flip( self::DESIGN_KEYS ) ) : array();
	}

	/**
	 * Stores a design draft for the current user's preview frame.
	 *
	 * @param array $input Design values.
	 * @return array Sanitized draft.
	 */
	public static function store_preview( array $input ) {
		$input = array_intersect_key( $input, array_flip( self::DESIGN_KEYS ) );
		$clean = array_intersect_key( self::sanitize( $input, self::saved() ), array_flip( self::DESIGN_KEYS ) );
		set_transient( self::preview_key(), $clean, 30 * MINUTE_IN_SECONDS );
		return $clean;
	}

	/**
	 * Transient key of the current user's preview draft.
	 *
	 * @return string
	 */
	private static function preview_key() {
		return 'kdocs_design_preview_' . get_current_user_id();
	}

	/**
	 * Single setting.
	 *
	 * @param string $key     Key.
	 * @param mixed  $default Fallback.
	 * @return mixed
	 */
	public static function get( $key, $default = null ) {
		$all = self::all();
		return array_key_exists( $key, $all ) ? $all[ $key ] : $default;
	}

	/**
	 * Maps renamed keys to their replacements (the new key wins when both exist).
	 *
	 * @param array $values Settings.
	 * @return array
	 */
	public static function rename( array $values ) {
		foreach ( self::RENAMED as $old => $to ) {
			if ( ! array_key_exists( $old, $values ) ) {
				continue;
			}
			if ( ! array_key_exists( $to[0], $values ) ) {
				$values[ $to[0] ] = $to[1] ? call_user_func( $to[1], $values[ $old ] ) : $values[ $old ];
			}
			unset( $values[ $old ] );
		}
		return $values;
	}

	/**
	 * `widget_exclude_docs` → `widget_display`. Saved 1.0 values can't be trusted
	 * (every save stored the old default, which hid the widget on docs pages),
	 * so the new default is used.
	 *
	 * @return string
	 */
	public static function map_widget_exclude() {
		return 'everywhere';
	}

	/**
	 * Stored settings brought up to date: renamed keys mapped, removed keys
	 * dropped, every value re-sanitized to its current type. Only stored keys are
	 * kept, so defaults keep applying to the rest.
	 *
	 * @param array $saved Stored settings.
	 * @return array
	 */
	public static function upgrade( array $saved ) {
		$saved    = self::rename( $saved );
		$defaults = self::defaults();
		$known    = array_intersect_key( $saved, $defaults );
		$clean    = self::sanitize( $known, wp_parse_args( $known, $defaults ) );
		return array_intersect_key( $clean, $known );
	}

	/**
	 * Saves (partial) settings with sanitization driven by the default types.
	 *
	 * @param array $input Raw values.
	 * @return array Saved settings.
	 */
	public static function update( array $input ) {
		$current  = self::saved();
		$old_slug = $current['docs_slug'] . '|' . $current['category_base'];
		$current  = self::sanitize( $input, $current );

		update_option( self::OPTION, $current );
		self::$saved = $current;
		self::$cache = null;

		if ( $old_slug !== $current['docs_slug'] . '|' . $current['category_base'] ) {
			update_option( 'kdocs_flush_rewrite', 1 );
		}

		return $current;
	}

	/**
	 * Sanitizes (partial) input over existing values, driven by the default types.
	 *
	 * @param array $input   Raw values.
	 * @param array $current Values to update.
	 * @return array
	 */
	public static function sanitize( array $input, array $current ) {
		$defaults = self::defaults();
		$input    = self::rename( $input );

		foreach ( $input as $key => $value ) {
			if ( ! array_key_exists( $key, $defaults ) ) {
				continue;
			}
			// Unchanged masked secrets come back from the browser as-is: keep the stored value.
			if ( in_array( $key, self::secret_keys(), true ) && is_string( $value ) && false !== strpos( $value, '•' ) ) {
				continue;
			}
			$type = gettype( $defaults[ $key ] );
			switch ( $type ) {
				case 'boolean':
					$current[ $key ] = (bool) rest_sanitize_boolean( $value );
					break;
				case 'integer':
					$current[ $key ] = (int) $value;
					if ( 'analytics_retention' === $key ) {
						$current[ $key ] = max( 7, min( 730, $current[ $key ] ) );
					} elseif ( 'feedback_retention' === $key ) {
						$current[ $key ] = max( 0, min( 3650, $current[ $key ] ) );
					} elseif ( in_array( $key, array( 'ai_budget', 'summary_min_words' ), true ) ) {
						$current[ $key ] = max( 0, min( 100000, $current[ $key ] ) );
					} elseif ( 'impact_ticket_rate' === $key ) {
						$current[ $key ] = max( 0, min( 100, $current[ $key ] ) );
					} elseif ( 'radius' === $key ) {
						$current[ $key ] = max( 0, min( 24, $current[ $key ] ) );
					} elseif ( in_array( $key, array( 'docs_logo', 'docs_logo_dark', 'docs_favicon' ), true ) && $current[ $key ] && ! wp_attachment_is_image( $current[ $key ] ) && 'image/svg+xml' !== get_post_mime_type( $current[ $key ] ) ) {
						$current[ $key ] = 0;
					}
					break;
				default:
					if ( 'custom_css' === $key ) {
						$current[ $key ] = wp_strip_all_tags( (string) $value );
					} elseif ( 'primary_color' === $key ) {
						$current[ $key ] = sanitize_hex_color( $value ) ? sanitize_hex_color( $value ) : $defaults[ $key ];
					} elseif ( in_array( $key, array( 'docs_slug', 'category_base' ), true ) ) {
						$slug            = sanitize_title( $value );
						$current[ $key ] = $slug ? $slug : $defaults[ $key ];
					} elseif ( 'widget_display' === $key ) {
						$current[ $key ] = in_array( $value, array( 'everywhere', 'docs', 'not_docs' ), true ) ? $value : 'everywhere';
					} elseif ( in_array( $key, array( 'widget_contact_url', 'contact_url', 'webhook_url', 'slack_webhook_url' ), true ) ) {
						$current[ $key ] = esc_url_raw( trim( (string) $value ) );
					} elseif ( 'ai_instructions' === $key ) {
						$current[ $key ] = sanitize_textarea_field( (string) $value );
					} elseif ( 'ai_provider' === $key ) {
						$current[ $key ] = in_array( $value, array( 'anthropic', 'openai', 'google' ), true ) ? $value : 'anthropic';
					} elseif ( 'search_provider' === $key ) {
						$current[ $key ] = in_array( $value, array( 'wordpress', 'algolia' ), true ) ? $value : 'wordpress'; // phpcs:ignore WordPress.WP.CapitalPDangit -- Option value, not the brand.
					} elseif ( 'algolia_app_id' === $key ) {
						// Becomes part of the Algolia API host name.
						$current[ $key ] = strtoupper( preg_replace( '/[^A-Za-z0-9]/', '', (string) $value ) );
					} elseif ( 'algolia_index' === $key ) {
						$index           = preg_replace( '/[^A-Za-z0-9_\-]/', '', (string) $value );
						$current[ $key ] = $index ? $index : $defaults[ $key ];
					} elseif ( 'notify_email' === $key ) {
						$current[ $key ] = sanitize_email( $value );
					} elseif ( isset( self::CHOICES[ $key ] ) ) {
						$current[ $key ] = in_array( $value, self::CHOICES[ $key ], true ) ? $value : self::CHOICES[ $key ][0];
					} elseif ( 'report_recipients' === $key ) {
						$current[ $key ] = implode( ', ', array_filter( array_map( 'sanitize_email', preg_split( '/[\s,;]+/', (string) $value ) ) ) );
					} elseif ( 'cors_origins' === $key ) {
						$current[ $key ] = implode( "\n", array_filter( array_map( static fn( $o ) => '*' === $o ? '*' : esc_url_raw( $o, array( 'http', 'https' ) ), preg_split( '/[\s,]+/', (string) $value ) ) ) );
					} elseif ( 'discord_public_key' === $key ) {
						$current[ $key ] = strtolower( preg_replace( '/[^0-9a-fA-F]/', '', (string) $value ) );
					} elseif ( 'docs_header_links' === $key ) {
						$current[ $key ] = sanitize_textarea_field( (string) $value );
					} else {
						$current[ $key ] = sanitize_text_field( (string) $value );
					}
			}
		}

		// Free plan cannot persist premium-only layouts.
		if ( ! Features::is_pro() && ! in_array( $current['home_layout'], array( 'cards', 'list' ), true ) ) {
			$current['home_layout'] = 'cards';
		}

		return $current;
	}
}