<?php
/**
 * Plugin bootstrap singleton.
 *
 * @package Tagsmith
 */

declare(strict_types=1);

namespace Tagsmith;

use Tagsmith\Admin\Assets;
use Tagsmith\Admin\OAuthReturn;
use Tagsmith\Auth\Connection;
use Tagsmith\Auth\OAuthFlow;
use Tagsmith\Auth\TokenStore;
use Tagsmith\Clarity\ClarityApi;
use Tagsmith\Clarity\ClaritySync;
use Tagsmith\Clarity\Insights;
use Tagsmith\Clarity\SnapshotStore;
use Tagsmith\Google\AdminApi;
use Tagsmith\Google\DataApi;
use Tagsmith\Google\HttpClient;
use Tagsmith\Google\SearchConsoleApi;
use Tagsmith\Health\HealthCheck;
use Tagsmith\Migration\Upgrader;
use Tagsmith\Reports\ReportRegistry;
use Tagsmith\Reports\ReportRunner;
use Tagsmith\Rest\Routes;
use Tagsmith\Tracking\TagRenderer;

defined( 'ABSPATH' ) || exit;

/**
 * Central service locator for the plugin. Lazily creates and memoizes
 * services; each getter is added by the task that introduces the class.
 */
final class Plugin {

	/**
	 * The relay run by the plugin's author, used unless the constant or the
	 * filter points somewhere else.
	 */
	public const DEFAULT_RELAY_URL = 'https://connect.shivaatripathi.com';

	/**
	 * Singleton instance.
	 *
	 * @var self|null
	 */
	private static ?self $instance = null;

	/**
	 * Memoized Settings service.
	 *
	 * @var Settings|null
	 */
	private ?Settings $settings = null;

	/**
	 * Memoized Capabilities service.
	 *
	 * @var Capabilities|null
	 */
	private ?Capabilities $capabilities = null;

	/**
	 * Memoized TokenStore service.
	 *
	 * @var TokenStore|null
	 */
	private ?TokenStore $tokens = null;

	/**
	 * Memoized Connection service.
	 *
	 * @var Connection|null
	 */
	private ?Connection $connection = null;

	/**
	 * Memoized HttpClient service.
	 *
	 * @var HttpClient|null
	 */
	private ?HttpClient $http = null;

	/**
	 * Memoized OAuthFlow service.
	 *
	 * @var OAuthFlow|null
	 */
	private ?OAuthFlow $oauth = null;

	/**
	 * Memoized AdminApi service.
	 *
	 * @var AdminApi|null
	 */
	private ?AdminApi $admin_api = null;

	/**
	 * Memoized DataApi service.
	 *
	 * @var DataApi|null
	 */
	private ?DataApi $data_api = null;

	/**
	 * Memoized SearchConsoleApi service.
	 *
	 * @var SearchConsoleApi|null
	 */
	private ?SearchConsoleApi $search_console = null;

	/**
	 * Memoized ReportRegistry service.
	 *
	 * @var ReportRegistry|null
	 */
	private ?ReportRegistry $registry = null;

	/**
	 * Memoized ReportRunner service.
	 *
	 * @var ReportRunner|null
	 */
	private ?ReportRunner $reports = null;

	/**
	 * Memoized HealthCheck service.
	 *
	 * @var HealthCheck|null
	 */
	private ?HealthCheck $health = null;

	/**
	 * Memoized Assets service.
	 *
	 * @var Assets|null
	 */
	private ?Assets $assets = null;

	/**
	 * Memoized Clarity SnapshotStore service.
	 *
	 * @var SnapshotStore|null
	 */
	private ?SnapshotStore $clarity_store = null;

	/**
	 * Memoized ClaritySync service.
	 *
	 * @var ClaritySync|null
	 */
	private ?ClaritySync $clarity = null;

	/**
	 * Get the singleton instance.
	 */
	public static function instance(): self {
		if ( null === self::$instance ) {
			self::$instance = new self();
		}

		return self::$instance;
	}

	/**
	 * Private constructor. Use instance().
	 */
	private function __construct() {}

	/**
	 * Runs on plugins_loaded: wires up services that need to hook in
	 * immediately, and fires the tagsmith_loaded action for the rest of
	 * the plugin to hook into.
	 *
	 * There is no load_plugin_textdomain() call: since WordPress 4.6, core
	 * loads WordPress.org language packs for the plugin's slug on demand.
	 */
	public function boot(): void {
		( new Upgrader() )->maybe_upgrade();

		$this->capabilities()->register();
		( new OAuthReturn( fn(): OAuthFlow => $this->oauth() ) )->register();
		( new Routes( $this ) )->register();
		$this->health()->register_site_health();

		// The posts_column warm-up handler runs on its own wp-cron request,
		// so it is registered unconditionally rather than only in is_admin().
		$posts_column = new Admin\PostsColumn( $this );
		$posts_column->register_cron();

		// So does the Clarity snapshot sync. The closure keeps boot() from
		// building ClaritySync (and its TokenStore) on every request.
		add_action( ClaritySync::CRON_HOOK, fn() => $this->clarity()->run_scheduled() );

		// Saving a post (anywhere) forgets its cached Clarity page titles.
		add_action( 'post_updated', array( Insights::class, 'forget_post_titles' ), 10, 3 );
		add_action( 'save_post', array( Insights::class, 'forget_post_titles' ), 10, 2 );

		if ( is_admin() ) {
			( new Admin\Menu( $this ) )->register();
			$this->assets()->register();
			$posts_column->register();
			( new Admin\EditorPanel( $this ) )->register();
			( new Admin\DashboardWidget( $this ) )->register();
			( new Admin\PrivacyPolicy( $this->settings() ) )->register();
		} else {
			( new TagRenderer( $this->settings() ) )->register();
		}

		add_filter( 'wp_consent_api_registered_' . plugin_basename( TAGSMITH_FILE ), '__return_true' );

		do_action( 'tagsmith_loaded', $this );
	}

	/**
	 * The typed settings store.
	 */
	public function settings(): Settings {
		if ( null === $this->settings ) {
			$this->settings = new Settings();
		}

		return $this->settings;
	}

	/**
	 * The report-viewing capability mapping.
	 */
	public function capabilities(): Capabilities {
		if ( null === $this->capabilities ) {
			$this->capabilities = new Capabilities( $this->settings() );
		}

		return $this->capabilities;
	}

	/**
	 * The encrypted-at-rest token store.
	 */
	public function tokens(): TokenStore {
		if ( null === $this->tokens ) {
			$this->tokens = new TokenStore();
		}

		return $this->tokens;
	}

	/**
	 * The Google connection state.
	 */
	public function connection(): Connection {
		if ( null === $this->connection ) {
			$this->connection = new Connection( $this->tokens() );
		}

		return $this->connection;
	}

	/**
	 * The HTTP client for Google and relay calls.
	 */
	public function http(): HttpClient {
		if ( null === $this->http ) {
			$this->http = new HttpClient();
		}

		return $this->http;
	}

	/**
	 * The Google OAuth flow (relay and BYO).
	 */
	public function oauth(): OAuthFlow {
		if ( null === $this->oauth ) {
			$this->oauth = new OAuthFlow( $this->settings(), $this->connection(), $this->http(), self::relay_url(), $this->tokens() );
		}

		return $this->oauth;
	}

	/**
	 * The Google Analytics Admin API client (accounts, properties, streams).
	 */
	public function admin_api(): AdminApi {
		if ( null === $this->admin_api ) {
			$this->admin_api = new AdminApi( $this->http(), $this->oauth() );
		}

		return $this->admin_api;
	}

	/**
	 * The Google Analytics Data API client (reports).
	 */
	public function data_api(): DataApi {
		if ( null === $this->data_api ) {
			$this->data_api = new DataApi( $this->http(), $this->oauth() );
		}

		return $this->data_api;
	}

	/**
	 * The Google Search Console API client.
	 */
	public function search_console(): SearchConsoleApi {
		if ( null === $this->search_console ) {
			$this->search_console = new SearchConsoleApi( $this->http(), $this->oauth() );
		}

		return $this->search_console;
	}

	/**
	 * The report definitions registry.
	 */
	public function registry(): ReportRegistry {
		if ( null === $this->registry ) {
			$this->registry = new ReportRegistry();
		}

		return $this->registry;
	}

	/**
	 * The report runner (cached Google reports).
	 */
	public function reports(): ReportRunner {
		if ( null === $this->reports ) {
			$this->reports = new ReportRunner( $this->settings(), $this->registry(), $this->data_api(), $this->search_console(), $this->connection() );
		}

		return $this->reports;
	}

	/**
	 * The diagnostics service (connection, tag, conflicts, environment,
	 * consent), also registered with Site Health. Built with closures for
	 * OAuthFlow/AdminApi/SearchConsoleApi so boot() never constructs
	 * OAuthFlow eagerly (it needs TokenStore, which needs the auth salts).
	 */
	public function health(): HealthCheck {
		if ( null === $this->health ) {
			$this->health = new HealthCheck(
				$this->settings(),
				$this->connection(),
				fn(): OAuthFlow => $this->oauth(),
				fn(): AdminApi => $this->admin_api(),
				fn(): SearchConsoleApi => $this->search_console()
			);
		}

		return $this->health;
	}

	/**
	 * The admin asset enqueuer, also the single source of the
	 * `window.tagsmithConfig` payload every Tagsmith JS entry
	 * (dashboard, settings, editor, widget) reads.
	 */
	public function assets(): Assets {
		if ( null === $this->assets ) {
			$this->assets = new Assets( $this );
		}

		return $this->assets;
	}

	/**
	 * The local table of Clarity Data Export snapshots.
	 */
	public function clarity_store(): SnapshotStore {
		if ( null === $this->clarity_store ) {
			$this->clarity_store = new SnapshotStore();
		}

		return $this->clarity_store;
	}

	/**
	 * The Clarity Data Export sync: token (write-only), status, budget and
	 * the twice-daily cron.
	 */
	public function clarity(): ClaritySync {
		if ( null === $this->clarity ) {
			$this->clarity = new ClaritySync( $this->tokens(), new ClarityApi(), $this->clarity_store(), $this->settings() );
		}

		return $this->clarity;
	}

	/**
	 * The URL of the Tagsmith relay service, used for the "relay"
	 * connection mode. Overridable via the TAGSMITH_RELAY_URL constant,
	 * then the tagsmith_relay_url filter.
	 */
	public static function relay_url(): string {
		return untrailingslashit(
			defined( 'TAGSMITH_RELAY_URL' )
				? TAGSMITH_RELAY_URL
				: apply_filters( 'tagsmith_relay_url', self::DEFAULT_RELAY_URL )
		);
	}

	/**
	 * Whether the relay in use is the one run by the plugin's author. Copy
	 * that says who runs the relay is only true then.
	 */
	public static function relay_is_default(): bool {
		return self::relay_url() === self::DEFAULT_RELAY_URL;
	}

	/**
	 * The domain Google names on its "Google hasn't verified this app"
	 * screen ("Go to <domain> (unsafe)"): the home page domain of the OAuth
	 * app behind the relay. It is not the relay's own host, so it is kept
	 * apart from relay_url(). The relay pins the same value
	 * (UNVERIFIED_APP_DOMAIN in relay/src/confirm.ts).
	 *
	 * That domain is the author's only with the author's relay. With another
	 * relay the filter starts from an empty string, and only a host name it
	 * returns is used; anything else leaves no domain, and the Connect step
	 * then says nothing about Google's warning.
	 */
	public static function oauth_app_domain(): string {
		/**
		 * Filters the domain the Connect step names for Google's
		 * unverified-app screen. With your own relay, return your OAuth app's
		 * home domain here (a host name, without a scheme, a path or a
		 * port). When nothing valid is returned, the note is not shown.
		 *
		 * @since 2.0.0
		 *
		 * @param string $domain The OAuth app's home page domain: the author's with the default relay, otherwise an empty string.
		 */
		$domain = apply_filters( 'tagsmith_oauth_app_domain', self::relay_is_default() ? 'shivaatripathi.com' : '' );

		if ( ! is_string( $domain ) ) {
			return '';
		}

		$domain = strtolower( $domain );

		return 1 === preg_match( '/^(?=.{1,253}$)([a-z0-9-]+\.)+[a-z]{2,}$/D', $domain ) ? $domain : '';
	}
}