<?php
/**
 * Settings screen controller.
 *
 * @package FormPilot
 * @since   1.0.0
 */

declare( strict_types = 1 );

namespace FormPilot\Admin\Pages;

use FormPilot\Security\Capabilities;
use FormPilot\Security\Request;
use FormPilot\Settings\Settings;
use FormPilot\Settings\SettingsRegistry;
use FormPilot\Settings\SettingsTransfer;

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

/**
 * Hosts the plugin settings, split across tabs.
 *
 * Storage and validation belong to the Settings API; this controller only picks
 * the tab and hands its page slug to the view.
 *
 * @since 1.0.0
 */
final class SettingsPage extends AbstractPage {

	/**
	 * Page slug.
	 */
	public const SLUG = 'formpilot-settings';

	/**
	 * Option group registered with the Settings API.
	 */
	public const OPTION_GROUP = SettingsRegistry::GROUP;

	/**
	 * Returns the browser title.
	 */
	public function page_title(): string {
		return __( 'Settings', 'devplugins-custom-form-builder' );
	}

	/**
	 * Returns the menu label.
	 */
	public function menu_title(): string {
		return __( 'Settings', 'devplugins-custom-form-builder' );
	}

	/**
	 * Returns the required capability.
	 */
	public function capability(): string {
		return Capabilities::get( Capabilities::MANAGE_SETTINGS );
	}

	/**
	 * Returns the view path.
	 */
	protected function view(): string {
		return 'admin/settings/general';
	}

	/**
	 * Returns the data passed to the view.
	 *
	 * @return array<string, mixed> Variables exposed to the template.
	 */
	protected function data(): array {
		$tab = $this->current_tab();

		return array(
			'page_title'   => $this->page_title(),
			'tabs'         => SettingsRegistry::tabs(),
			'current_tab'  => $tab,
			'option_group' => self::OPTION_GROUP,
			'option_name'  => Settings::OPTION,
			'tab_marker'   => SettingsRegistry::TAB_MARKER,
			'section_page' => SettingsRegistry::page( $tab ),
			'tab_base_url' => $this->url(),
			'transfer'     => $this->transfer(),
			'notice'       => $this->notice(),
		);
	}

	/**
	 * Returns what the import and export controls need.
	 *
	 * @return array<string, string> Endpoint, actions and their nonces.
	 */
	private function transfer(): array {
		return array(
			'url'           => admin_url( 'admin-post.php' ),
			'export_action' => SettingsTransfer::EXPORT_ACTION,
			'import_action' => SettingsTransfer::IMPORT_ACTION,
			'export_nonce'  => wp_create_nonce( SettingsTransfer::EXPORT_ACTION ),
			'import_nonce'  => wp_create_nonce( SettingsTransfer::IMPORT_ACTION ),
		);
	}

	/**
	 * Builds the notice shown after an import.
	 *
	 * @return array{type: string, text: string}|null The notice, or null when there is nothing to report.
	 */
	private function notice(): ?array {
		$message = Request::key( 'formpilot_message' );

		if ( '' === $message ) {
			return null;
		}

		$count = max( 0, Request::int( 'formpilot_count' ) );

		return match ( $message ) {
			'imported'         => array(
				'type' => 'success',
				'text' => 0 === $count
					? __( 'The file was read and every setting already matched it.', 'devplugins-custom-form-builder' )
					: sprintf(
						/* translators: %s: Number of settings. */
						_n( '%s setting was imported.', '%s settings were imported.', $count, 'devplugins-custom-form-builder' ),
						number_format_i18n( $count )
					),
			),
			'import_missing'   => array(
				'type' => 'error',
				'text' => __( 'Choose a file to import.', 'devplugins-custom-form-builder' ),
			),
			'import_large'     => array(
				'type' => 'error',
				'text' => __( 'That file is too large to be a settings export.', 'devplugins-custom-form-builder' ),
			),
			'import_unreadable' => array(
				'type' => 'error',
				'text' => __( 'That file could not be read as JSON.', 'devplugins-custom-form-builder' ),
			),
			'import_foreign'   => array(
				'type' => 'error',
				'text' => __( 'That file is not a FormPilot — Smart Form Builder settings export.', 'devplugins-custom-form-builder' ),
			),
			default            => null,
		};
	}

	/**
	 * Returns the tab being displayed.
	 */
	private function current_tab(): string {
		$tab  = Request::key( 'tab' );
		$tabs = SettingsRegistry::tabs();

		if ( '' !== $tab && array_key_exists( $tab, $tabs ) ) {
			return $tab;
		}

		// A tab that has since been folded into another one.
		$moved = SettingsRegistry::moved_tabs();

		if ( isset( $moved[ $tab ] ) && array_key_exists( $moved[ $tab ], $tabs ) ) {
			return $moved[ $tab ];
		}

		return (string) array_key_first( $tabs );
	}
}