<?php
/**
 * Admin menu, tabs and routing.
 *
 * @package WC_Email_Discount_Manager
 */

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

/**
 * Registers the admin page under WooCommerce and routes tabs/actions.
 */
class WC_EDM_Admin {

	/**
	 * Admin page slug.
	 */
	/** Cache key for the dashboard card's counts. */
	const CARD_TRANSIENT = 'wc_edm_card_counts';

	const PAGE_SLUG = 'wc-email-discounts';

	/**
	 * Groups controller.
	 *
	 * @var WC_EDM_Admin_Groups
	 */
	private $groups;

	/**
	 * Emails controller.
	 *
	 * @var WC_EDM_Admin_Emails
	 */
	private $emails;

	/**
	 * Shipping controller.
	 *
	 * @var WC_EDM_Admin_Shipping
	 */
	private $shipping;

	/**
	 * Audit log controller.
	 *
	 * @var WC_EDM_Admin_Audit
	 */
	private $audit;

	/**
	 * Hook everything up.
	 */
	public function __construct() {
		// Each sub-controller lives in its own file. Guarding here means an
		// incomplete plugin folder costs a tab, not the whole admin screen.
		$this->groups   = class_exists( 'WC_EDM_Admin_Groups' ) ? new WC_EDM_Admin_Groups() : null;
		$this->emails   = class_exists( 'WC_EDM_Admin_Emails' ) ? new WC_EDM_Admin_Emails() : null;
		$this->shipping = class_exists( 'WC_EDM_Admin_Shipping' ) ? new WC_EDM_Admin_Shipping() : null;
		$this->audit    = class_exists( 'WC_EDM_Admin_Audit' ) ? new WC_EDM_Admin_Audit() : null;

		add_action( 'admin_menu', array( $this, 'register_menu' ) );
		add_filter( 'wpmgr_dashboard_cards', array( $this, 'dashboard_card' ) );
		add_action( 'admin_init', array( $this, 'handle_actions' ) );
		add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_assets' ) );
	}

	/**
	 * This plugin's card on the shared Nolimit dashboard.
	 *
	 * The contract says implementations must not measure anything here,
	 * because this filter runs on an admin page load and a slow card makes
	 * somebody else's dashboard slow in a way they cannot attribute. Two
	 * COUNT(*) on small indexed tables is the most this may cost, and even
	 * that is cached: the dashboard is a page people leave open.
	 *
	 * @param array $cards The cards so far.
	 * @return array
	 */
	public function dashboard_card( $cards ) {
		$counts = get_transient( self::CARD_TRANSIENT );

		if ( ! is_array( $counts ) ) {
			$counts = array(
				'groups' => WC_EDM_DB::count_groups(),
				'emails' => WC_EDM_DB::count_emails( true ),
			);
			set_transient( self::CARD_TRANSIENT, $counts, 5 * MINUTE_IN_SECONDS );
		}

		// "warn", not "fail": a shop that has installed this and not set it up
		// yet is not broken, it is unfinished. Reserving red for actual
		// breakage is what keeps red worth reading.
		$status = $counts['groups'] > 0 && $counts['emails'] > 0 ? 'ok' : 'warn';

		$cards[] = array(
			'title'    => __( 'Discounts', 'wc-email-discount' ),
			'status'   => $status,
			'headline' => sprintf(
				/* translators: %s: number of email addresses that currently receive a discount. */
				_n( '%s address gets a discount', '%s addresses get a discount', $counts['emails'], 'wc-email-discount' ),
				number_format_i18n( $counts['emails'] )
			),
			'lines'    => array(
				__( 'Groups', 'wc-email-discount' )            => number_format_i18n( $counts['groups'] ),
				__( 'Active addresses', 'wc-email-discount' )  => number_format_i18n( $counts['emails'] ),
			),
			'url'      => admin_url( 'admin.php?page=' . self::PAGE_SLUG ),
			// The plugin's own colour. Deliberately not WooCommerce's brand
			// purple; see the note in assets/icon.svg.
			'colour'   => '#1a7a52',
		);

		return $cards;
	}

	/**
	 * Register the page under the shared Nolimit menu.
	 *
	 * wpmgr_ensure_menu() must be called first and is a no-op when another of
	 * the five plugins already registered the parent — whichever booted first
	 * owns it, and none of them may assume it is theirs.
	 *
	 * The page slug is unchanged, so admin.php?page=… still resolves: moving a
	 * page between parents does not move its URL, and an existing bookmark or
	 * a link in an email keeps working.
	 */
	public function register_menu() {
		if ( function_exists( 'wpmgr_ensure_menu' ) ) {
			wpmgr_ensure_menu();
			$parent = WPMGR_MENU_SLUG;
		} else {
			// The shared file is missing — a half-copied upgrade. Fall back to
			// the old home rather than losing the page entirely.
			$parent = 'woocommerce';
		}

		add_submenu_page(
			$parent,
			__( 'Discounts', 'wc-email-discount' ),
			__( 'Discounts', 'wc-email-discount' ),
			'manage_woocommerce',
			self::PAGE_SLUG,
			array( $this, 'render_page' )
		);
	}

	/**
	 * Enqueue admin CSS/JS on the plugin page only.
	 *
	 * @param string $hook Current admin page hook.
	 */
	public function enqueue_assets( $hook ) {
		if ( false === strpos( $hook, self::PAGE_SLUG ) ) {
			return;
		}

		wp_enqueue_style(
			'wc-edm-admin',
			WC_EDM_PLUGIN_URL . 'assets/css/admin.css',
			array(),
			WC_EDM_VERSION
		);

		wp_enqueue_script(
			'wc-edm-admin',
			WC_EDM_PLUGIN_URL . 'assets/js/admin.js',
			array( 'jquery', 'jquery-ui-sortable' ),
			WC_EDM_VERSION,
			true
		);

		wp_localize_script(
			'wc-edm-admin',
			'wcEdmAdmin',
			array(
				'confirmDelete' => __( 'Are you sure you want to delete this item? This cannot be undone.', 'wc-email-discount' ),
			)
		);
	}

	/**
	 * Get the currently active tab.
	 *
	 * @return string
	 */
	public function current_tab() {
		$tab  = isset( $_GET['tab'] ) ? sanitize_key( wp_unslash( $_GET['tab'] ) ) : 'dashboard'; // phpcs:ignore WordPress.Security.NonceVerification.Recommended
		$tabs = array_keys( $this->get_tabs() );

		return in_array( $tab, $tabs, true ) ? $tab : 'dashboard';
	}

	/**
	 * Tab definitions.
	 *
	 * @return array
	 */
	private function get_tabs() {
		$tabs = array( 'dashboard' => __( 'Dashboard', 'wc-email-discount' ) );

		// Only offer tabs whose controller actually loaded.
		if ( $this->groups ) {
			$tabs['groups'] = __( 'Discount Groups', 'wc-email-discount' );
		}

		if ( $this->emails ) {
			$tabs['emails'] = __( 'Email Assignments', 'wc-email-discount' );
		}

		if ( $this->shipping ) {
			$tabs['shipping'] = __( 'Shipping Rules', 'wc-email-discount' );
		}

		if ( $this->audit ) {
			$tabs['audit'] = __( 'Audit Log', 'wc-email-discount' );
		}

		return $tabs;
	}

	/**
	 * Handle POST/GET actions before any output (allows redirects).
	 */
	public function handle_actions() {
		if ( ! isset( $_GET['page'] ) || self::PAGE_SLUG !== $_GET['page'] ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended
			return;
		}

		if ( ! current_user_can( 'manage_woocommerce' ) ) {
			return;
		}

		switch ( $this->current_tab() ) {
			case 'groups':
				$this->groups->handle_actions();
				break;
			case 'emails':
				$this->emails->handle_actions();
				break;
			case 'shipping':
				$this->shipping->handle_actions();
				break;
			case 'audit':
				$this->audit->handle_actions();
				break;
		}
	}

	/**
	 * Render the admin page with tab navigation.
	 */
	public function render_page() {
		if ( ! current_user_can( 'manage_woocommerce' ) ) {
			wp_die( esc_html__( 'You do not have permission to access this page.', 'wc-email-discount' ) );
		}

		$current = $this->current_tab();
		?>
		<div class="wrap wc-edm-wrap">
			<h1><?php esc_html_e( 'Email Discounts', 'wc-email-discount' ); ?></h1>

			<?php $this->render_notices(); ?>

			<nav class="nav-tab-wrapper wc-edm-nav">
				<?php foreach ( $this->get_tabs() as $slug => $label ) : ?>
					<a href="<?php echo esc_url( WC_EDM_Helpers::admin_url( array( 'tab' => $slug ) ) ); ?>"
						class="nav-tab <?php echo $current === $slug ? 'nav-tab-active' : ''; ?>">
						<?php echo esc_html( $label ); ?>
					</a>
				<?php endforeach; ?>
			</nav>

			<div class="wc-edm-content">
				<?php
				switch ( $current ) {
					case 'groups':
						$this->groups->render();
						break;
					case 'emails':
						$this->emails->render();
						break;
					case 'shipping':
						$this->shipping->render();
						break;
					case 'audit':
						$this->audit->render();
						break;
					default:
						$this->render_dashboard();
						break;
				}
				?>
			</div>
		</div>
		<?php
	}

	/**
	 * Render success/error notices based on the ?message= query arg.
	 */
	private function render_notices() {
		if ( ! isset( $_GET['message'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification.Recommended
			return;
		}

		$message = sanitize_key( wp_unslash( $_GET['message'] ) ); // phpcs:ignore WordPress.Security.NonceVerification.Recommended

		$messages = array(
			'saved'   => array( 'success', __( 'Saved successfully.', 'wc-email-discount' ) ),
			'deleted' => array( 'success', __( 'Deleted successfully.', 'wc-email-discount' ) ),
			'error'   => array( 'error', __( 'Something went wrong. Please try again.', 'wc-email-discount' ) ),
		);

		if ( ! isset( $messages[ $message ] ) ) {
			return;
		}

		list( $type, $text ) = $messages[ $message ];

		printf(
			'<div class="notice notice-%1$s is-dismissible"><p>%2$s</p></div>',
			esc_attr( $type ),
			esc_html( $text )
		);
	}

	/**
	 * Render the dashboard tab: stats cards, quick actions, recent groups.
	 */
	private function render_dashboard() {
		$group_count  = WC_EDM_DB::count_groups();
		$email_count  = WC_EDM_DB::count_emails();
		$active_count = WC_EDM_DB::count_emails( true );
		$recent       = WC_EDM_DB::get_recent_groups( 5 );
		?>
		<div class="wc-edm-stats">
			<div class="wc-edm-stat-card">
				<span class="wc-edm-stat-number"><?php echo esc_html( $group_count ); ?></span>
				<span class="wc-edm-stat-label"><?php esc_html_e( 'Discount Groups', 'wc-email-discount' ); ?></span>
			</div>
			<div class="wc-edm-stat-card">
				<span class="wc-edm-stat-number"><?php echo esc_html( $email_count ); ?></span>
				<span class="wc-edm-stat-label"><?php esc_html_e( 'Email Assignments', 'wc-email-discount' ); ?></span>
			</div>
			<div class="wc-edm-stat-card">
				<span class="wc-edm-stat-number"><?php echo esc_html( $active_count ); ?></span>
				<span class="wc-edm-stat-label"><?php esc_html_e( 'Active Assignments', 'wc-email-discount' ); ?></span>
			</div>
		</div>

		<h2><?php esc_html_e( 'Quick Actions', 'wc-email-discount' ); ?></h2>
		<p class="wc-edm-quick-actions">
			<a class="button button-primary" href="<?php echo esc_url( WC_EDM_Helpers::admin_url( array( 'tab' => 'groups', 'action' => 'new' ) ) ); ?>">
				<?php esc_html_e( 'Add Discount Group', 'wc-email-discount' ); ?>
			</a>
			<a class="button button-primary" href="<?php echo esc_url( WC_EDM_Helpers::admin_url( array( 'tab' => 'emails', 'action' => 'new' ) ) ); ?>">
				<?php esc_html_e( 'Add Email Assignment', 'wc-email-discount' ); ?>
			</a>
			<a class="button" href="<?php echo esc_url( WC_EDM_Helpers::admin_url( array( 'tab' => 'shipping' ) ) ); ?>">
				<?php esc_html_e( 'Manage Shipping Rules', 'wc-email-discount' ); ?>
			</a>
		</p>

		<h2><?php esc_html_e( 'Recent Discount Groups', 'wc-email-discount' ); ?></h2>
		<?php if ( empty( $recent ) ) : ?>
			<p><?php esc_html_e( 'No discount groups yet. Create your first one to get started.', 'wc-email-discount' ); ?></p>
		<?php else : ?>
			<table class="widefat striped wc-edm-table">
				<thead>
					<tr>
						<th><?php esc_html_e( 'Name', 'wc-email-discount' ); ?></th>
						<th><?php esc_html_e( 'Discount', 'wc-email-discount' ); ?></th>
						<th><?php esc_html_e( 'Categories', 'wc-email-discount' ); ?></th>
						<th><?php esc_html_e( 'Created', 'wc-email-discount' ); ?></th>
					</tr>
				</thead>
				<tbody>
					<?php foreach ( $recent as $group ) : ?>
						<tr>
							<td>
								<a href="<?php echo esc_url( WC_EDM_Helpers::admin_url( array( 'tab' => 'groups', 'action' => 'edit', 'id' => (int) $group->id ) ) ); ?>">
									<strong><?php echo esc_html( $group->name ); ?></strong>
								</a>
							</td>
							<td><?php echo esc_html( wc_format_localized_decimal( $group->discount_percent ) ); ?>%</td>
							<td><?php echo esc_html( count( WC_EDM_DB::get_group_category_ids( (int) $group->id ) ) ); ?></td>
							<td><?php echo esc_html( date_i18n( get_option( 'date_format' ), strtotime( $group->created_at ) ) ); ?></td>
						</tr>
					<?php endforeach; ?>
				</tbody>
			</table>
		<?php endif; ?>
		<?php
	}
}