<?php
/**
 * WooCommerce automation page.
 *
 * @package IntelTele
 */

namespace IntelTele\Admin\Pages;

use IntelTele\Repositories\TemplateRepository;
use IntelTele\Services\SmsSegments;
use IntelTele\Services\TemplateRenderer;

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

final class WooCommercePage extends AbstractPage {
	/**
	 * Template repository.
	 *
	 * @var TemplateRepository
	 */
	private $template_repository;

	/**
	 * Template renderer.
	 *
	 * @var TemplateRenderer
	 */
	private $template_renderer;

	/**
	 * Template form values.
	 *
	 * @var array<string,string>
	 */
	private $template_form = array(
		'recipient_type' => 'customer',
		'order_status'   => 'wc-processing',
		'scheme'         => 'sms',
		'message'        => '',
		'preview_order'  => '',
	);

	/**
	 * Constructor.
	 */
	public function __construct() {
		$this->template_repository = new TemplateRepository();
		$this->template_renderer   = new TemplateRenderer();
	}

	/**
	 * Render page.
	 */
	public function render(): void {
		$this->prepare_page();
		$notice = $this->handle_template_submit();
		$status_notice = $this->handle_statuses_submit();
		if ( null === $notice ) {
			$notice = $status_notice;
		}
		$tabs = array(
			'statuses'  => __( 'Statuses', 'inteltele' ),
			'templates' => __( 'Messages', 'inteltele' ),
		);
		$tab  = $this->get_current_tab( 'statuses', array_keys( $tabs ) );

		$this->open_page( __( 'WooCommerce', 'inteltele' ) );
		$this->render_tabs( $tabs, $tab, 'inteltele-woocommerce' );
		$this->render_step_notice();
		$this->render_notice( $notice );

		if ( 'templates' === $tab ) {
			$this->render_templates_tab();
		} else {
			$this->render_statuses_tab();
		}

		$this->close_page();
	}

	/**
	 * Handle template form submission.
	 *
	 * @return array{type:string,messages:string[]}|null
	 */
	private function handle_template_submit(): ?array {
		if ( ! $this->is_post_request() ) {
			return null;
		}

		$action = isset( $_POST['inteltele_action'] ) ? sanitize_key( wp_unslash( $_POST['inteltele_action'] ) ) : '';

		if ( ! in_array( $action, array( 'save_template', 'preview_template' ), true ) ) {
			return null;
		}

		if ( ! current_user_can( 'inteltele_manage' ) ) {
			return array(
				'type'     => 'error',
				'messages' => array( __( 'You do not have permission to manage IntelTele templates.', 'inteltele' ) ),
			);
		}

		if ( ! isset( $_POST['inteltele_nonce'] ) || ! wp_verify_nonce( sanitize_text_field( wp_unslash( $_POST['inteltele_nonce'] ) ), 'inteltele_save_template' ) ) {
			return array(
				'type'     => 'error',
				'messages' => array( __( 'Security check failed. Please reload the page and try again.', 'inteltele' ) ),
			);
		}

		$this->template_form = array(
			'recipient_type' => isset( $_POST['recipient_type'] ) ? sanitize_key( wp_unslash( $_POST['recipient_type'] ) ) : 'customer',
			'order_status'   => isset( $_POST['order_status'] ) ? sanitize_key( wp_unslash( $_POST['order_status'] ) ) : 'wc-processing',
			'scheme'         => isset( $_POST['scheme'] ) ? sanitize_key( wp_unslash( $_POST['scheme'] ) ) : 'sms',
			'message'        => isset( $_POST['message'] ) ? sanitize_textarea_field( wp_unslash( $_POST['message'] ) ) : '',
			'preview_order'  => isset( $_POST['preview_order'] ) ? (string) absint( wp_unslash( $_POST['preview_order'] ) ) : '',
		);

		$errors = $this->validate_template_form();

		if ( ! empty( $errors ) ) {
			return array(
				'type'     => 'error',
				'messages' => $errors,
			);
		}

		if ( 'preview_template' === $action ) {
			return null;
		}

		$saved = $this->template_repository->save(
			$this->template_form['recipient_type'],
			$this->template_form['order_status'],
			$this->template_form['scheme'],
			$this->template_form['message'],
			get_current_user_id()
		);

		if ( $saved ) {
			$saved = $this->get_settings_repository()->save_wc_template_scheme(
				$this->template_form['recipient_type'],
				$this->template_form['order_status'],
				$this->template_form['scheme']
			);
		}

		if ( ! $saved ) {
			return array(
				'type'     => 'error',
				'messages' => array( __( 'Template could not be saved. Please try again.', 'inteltele' ) ),
			);
		}

		return array(
			'type'     => 'success',
			'messages' => array( __( 'Saved.', 'inteltele' ) ),
		);
	}

	/**
	 * Validate template form.
	 *
	 * @return string[]
	 */
	private function validate_template_form(): array {
		$errors = array();

		if ( ! in_array( $this->template_form['recipient_type'], array( 'customer', 'admin' ), true ) ) {
			$errors[] = __( 'Recipient type is invalid.', 'inteltele' );
		}

		if ( ! array_key_exists( $this->template_form['order_status'], $this->get_order_statuses() ) ) {
			$errors[] = __( 'Order status is invalid.', 'inteltele' );
		}

		if ( ! in_array( $this->template_form['scheme'], array( 'sms', 'viber', 'viber_sms' ), true ) ) {
			$errors[] = __( 'Selected sending scheme is invalid.', 'inteltele' );
		}

		if ( '' === trim( $this->template_form['message'] ) ) {
			$errors[] = __( 'Message text is required.', 'inteltele' );
		}

		$limit = 'sms' === $this->template_form['scheme'] ? 256 : 1000;

		if ( $this->string_length( $this->template_form['message'] ) > $limit ) {
			$errors[] = sprintf(
				/* translators: %d: character limit. */
				__( 'Message text must not exceed %d characters.', 'inteltele' ),
				$limit
			);
		}

		return $errors;
	}

	/**
	 * Get UTF-8 string length.
	 *
	 * @param string $value Value.
	 */
	private function string_length( string $value ): int {
		if ( function_exists( 'mb_strlen' ) ) {
			return mb_strlen( $value );
		}

		return strlen( $value );
	}

	/**
	 * Render submit notice.
	 *
	 * @param array{type:string,messages:string[]}|null $notice Notice.
	 */
	private function render_notice( ?array $notice ): void {
		if ( null === $notice ) {
			return;
		}

		$class = 'success' === $notice['type'] ? 'notice-success' : 'notice-error';

		echo '<div class="notice ' . esc_attr( $class ) . ' is-dismissible">';

		foreach ( $notice['messages'] as $message ) {
			echo '<p>' . esc_html( $message ) . '</p>';
		}

		echo '</div>';
	}

	/**
	 * Render statuses tab.
	 */
	private function render_statuses_tab(): void {
		$statuses = $this->get_order_statuses();
		$enabled  = $this->get_settings_repository()->get_wc_statuses();

		echo '<form method="post" action="">';
		wp_nonce_field( 'inteltele_save_wc_statuses', 'inteltele_nonce' );
		echo '<input type="hidden" name="inteltele_action" value="save_wc_statuses">';
		echo '<div class="inteltele-status-columns">';
		$this->render_status_column( __( 'Administrator', 'inteltele' ), 'admin', $statuses, $enabled['admin'] );
		$this->render_status_column( __( 'Customer', 'inteltele' ), 'customer', $statuses, $enabled['customer'] );
		echo '</div>';
		echo '<p class="submit"><button type="submit" class="button button-primary">' . esc_html__( 'Save', 'inteltele' ) . '</button></p>';
		echo '</form>';
	}

	/**
	 * Render templates tab.
	 */
	private function render_templates_tab(): void {
		$this->hydrate_template_form_from_query();
		$saved_template = $this->template_repository->get( $this->template_form['recipient_type'], $this->template_form['order_status'], $this->template_form['scheme'] );

		if ( '' === $this->template_form['message'] && $saved_template ) {
			$this->template_form['message'] = (string) $saved_template->message;
		}

		$unknown_variables = TemplateRenderer::find_unknown_variables( $this->template_form['message'] );
		$sms_segments      = SmsSegments::calculate( $this->template_form['message'] );
		$preview           = $this->get_template_preview();

		echo '<form method="post" action="">';
		wp_nonce_field( 'inteltele_save_template', 'inteltele_nonce' );
		echo '<table class="form-table" role="presentation"><tbody>';
		echo '<tr><th scope="row"><label for="inteltele-template-recipient">' . esc_html__( 'Recipient', 'inteltele' ) . '</label></th><td><select id="inteltele-template-recipient" name="recipient_type">';
		echo '<option value="customer"' . selected( $this->template_form['recipient_type'], 'customer', false ) . '>' . esc_html__( 'Customer', 'inteltele' ) . '</option>';
		echo '<option value="admin"' . selected( $this->template_form['recipient_type'], 'admin', false ) . '>' . esc_html__( 'Administrator', 'inteltele' ) . '</option>';
		echo '</select></td></tr>';
		echo '<tr><th scope="row"><label for="inteltele-template-status">' . esc_html__( 'Status', 'inteltele' ) . '</label></th><td><select id="inteltele-template-status" name="order_status">';

		foreach ( $this->get_order_statuses() as $status_key => $status_label ) {
			echo '<option value="' . esc_attr( $status_key ) . '"' . selected( $this->template_form['order_status'], $status_key, false ) . '>' . esc_html( $status_label ) . '</option>';
		}

		echo '</select></td></tr>';
		echo '<tr><th scope="row"><label for="inteltele-template-scheme">' . esc_html__( 'Scheme', 'inteltele' ) . '</label></th><td><select id="inteltele-template-scheme" name="scheme">';
		echo '<option value="sms"' . selected( $this->template_form['scheme'], 'sms', false ) . '>' . esc_html__( 'SMS', 'inteltele' ) . '</option>';
		echo '<option value="viber"' . selected( $this->template_form['scheme'], 'viber', false ) . '>' . esc_html__( 'Viber', 'inteltele' ) . '</option>';
		echo '<option value="viber_sms"' . selected( $this->template_form['scheme'], 'viber_sms', false ) . '>' . esc_html__( 'Viber + SMS', 'inteltele' ) . '</option>';
		echo '</select></td></tr>';
		echo '<tr><th scope="row"><label for="inteltele-template-message">' . esc_html__( 'Message', 'inteltele' ) . '</label></th><td>';
		echo '<textarea id="inteltele-template-message" name="message" class="large-text" rows="7" maxlength="1000" placeholder="' . esc_attr__( 'Message text...', 'inteltele' ) . '">' . esc_textarea( $this->template_form['message'] ) . '</textarea>';
		echo '<p><button type="button" class="button inteltele-transliterate">' . esc_html__( 'Transliteration', 'inteltele' ) . '</button></p>';
		echo '<p class="description">' . esc_html( sprintf( /* translators: %d: SMS segment count. */ __( 'Estimated SMS segments: %d', 'inteltele' ), $sms_segments ) ) . '</p>';

		if ( ! empty( $unknown_variables ) ) {
			echo '<div class="notice notice-warning inline"><p>';
			echo esc_html(
				sprintf(
					/* translators: %s: comma-separated variable names. */
					__( 'Unknown variables: %s', 'inteltele' ),
					implode( ', ', $unknown_variables )
				)
			);
			echo '</p></div>';
		}

		echo '</td></tr>';
		echo '<tr><th scope="row"><label for="inteltele-preview-order">' . esc_html__( 'Preview order', 'inteltele' ) . '</label></th><td>';
		$this->render_order_select();
		echo '<p class="description">' . esc_html__( 'Select an order to preview the final message with variables replaced.', 'inteltele' ) . '</p>';
		echo '</td></tr>';
		echo '</tbody></table>';
		echo '<p class="submit">';
		echo '<button type="submit" class="button" name="inteltele_action" value="preview_template">' . esc_html__( 'Preview', 'inteltele' ) . '</button> ';
		echo '<button type="submit" class="button button-primary" name="inteltele_action" value="save_template">' . esc_html__( 'Save', 'inteltele' ) . '</button>';
		echo '</p>';
		echo '</form>';

		if ( null !== $preview ) {
			echo '<h2>' . esc_html__( 'Message preview', 'inteltele' ) . '</h2>';
			echo '<textarea class="large-text" rows="5" readonly>' . esc_textarea( $preview ) . '</textarea>';
		}

		if ( $saved_template && ! empty( $saved_template->updated_at ) ) {
			echo '<p class="description">';
			echo esc_html(
				sprintf(
					/* translators: 1: date, 2: user ID. */
					__( 'Last updated: %1$s by user #%2$d.', 'inteltele' ),
					(string) $saved_template->updated_at,
					(int) $saved_template->updated_by
				)
			);
			echo '</p>';
		}
	}

	/**
	 * Hydrate template form values from GET for switching saved templates.
	 */
	private function hydrate_template_form_from_query(): void {
		if ( $this->is_post_request() ) {
			return;
		}

		$this->template_form['recipient_type'] = isset( $this->query['recipient_type'] ) ? sanitize_key( $this->query['recipient_type'] ) : $this->template_form['recipient_type'];
		$this->template_form['order_status']   = isset( $this->query['order_status'] ) ? sanitize_key( $this->query['order_status'] ) : $this->template_form['order_status'];
		$this->template_form['scheme']         = isset( $this->query['scheme'] )
			? sanitize_key( $this->query['scheme'] )
			: $this->get_settings_repository()->get_wc_template_scheme( $this->template_form['recipient_type'], $this->template_form['order_status'] );
	}

	/**
	 * Render recent order select.
	 */
	private function render_order_select(): void {
		echo '<select id="inteltele-preview-order" name="preview_order">';
		echo '<option value="">' . esc_html__( 'Select order', 'inteltele' ) . '</option>';

		foreach ( $this->get_recent_orders() as $order_id => $label ) {
			echo '<option value="' . esc_attr( (string) $order_id ) . '"' . selected( $this->template_form['preview_order'], (string) $order_id, false ) . '>' . esc_html( $label ) . '</option>';
		}

		echo '</select>';
	}

	/**
	 * Get recent WooCommerce orders.
	 *
	 * @return array<int,string>
	 */
	private function get_recent_orders(): array {
		if ( ! function_exists( 'wc_get_orders' ) ) {
			return array();
		}

		$orders = wc_get_orders(
			array(
				'limit'   => 20,
				'orderby' => 'date',
				'order'   => 'DESC',
				'return'  => 'objects',
			)
		);

		$options = array();

		foreach ( $orders as $order ) {
			if ( ! is_object( $order ) || ! method_exists( $order, 'get_id' ) ) {
				continue;
			}

			$order_id = (int) $order->get_id();
			$options[ $order_id ] = sprintf(
				/* translators: 1: order ID, 2: customer name. */
				__( 'Order #%1$d - %2$s', 'inteltele' ),
				$order_id,
				method_exists( $order, 'get_formatted_billing_full_name' ) ? (string) $order->get_formatted_billing_full_name() : ''
			);
		}

		return $options;
	}

	/**
	 * Get rendered preview text.
	 */
	private function get_template_preview(): ?string {
		if ( '' === $this->template_form['preview_order'] ) {
			return null;
		}

		if ( ! function_exists( 'wc_get_order' ) ) {
			return __( 'WooCommerce is not available.', 'inteltele' );
		}

		$order = wc_get_order( absint( $this->template_form['preview_order'] ) );

		if ( ! $order ) {
			return __( 'Selected order was not found.', 'inteltele' );
		}

		return $this->template_renderer->render( $this->template_form['message'], $order );
	}

	/**
	 * Render status checkbox column.
	 *
	 * @param string              $title Column title.
	 * @param string              $name Input group name.
	 * @param array<string,string> $statuses Order statuses.
	 * @param string[]            $enabled Enabled status keys.
	 */
	private function render_status_column( string $title, string $name, array $statuses, array $enabled ): void {
		echo '<fieldset class="inteltele-status-column">';
		echo '<legend>' . esc_html( $title ) . '</legend>';

		foreach ( $statuses as $status_key => $status_label ) {
			echo '<label>';
			echo '<input type="checkbox" name="' . esc_attr( $name ) . '_statuses[]" value="' . esc_attr( $status_key ) . '"' . checked( in_array( $status_key, $enabled, true ), true, false ) . '> ';
			echo esc_html( $status_label );
			echo '</label>';
		}

		echo '</fieldset>';
	}

	/**
	 * Handle statuses form.
	 *
	 * @return array{type:string,messages:string[]}|null
	 */
	private function handle_statuses_submit(): ?array {
		if ( ! $this->is_post_request() ) {
			return null;
		}

		$action = isset( $_POST['inteltele_action'] ) ? sanitize_key( wp_unslash( $_POST['inteltele_action'] ) ) : '';

		if ( 'save_wc_statuses' !== $action ) {
			return null;
		}

		if ( ! current_user_can( 'inteltele_manage' ) ) {
			return array(
				'type'     => 'error',
				'messages' => array( __( 'You do not have permission to manage WooCommerce status automation.', 'inteltele' ) ),
			);
		}

		if ( ! isset( $_POST['inteltele_nonce'] ) || ! wp_verify_nonce( sanitize_text_field( wp_unslash( $_POST['inteltele_nonce'] ) ), 'inteltele_save_wc_statuses' ) ) {
			return array(
				'type'     => 'error',
				'messages' => array( __( 'Security check failed. Please reload the page and try again.', 'inteltele' ) ),
			);
		}

		$available = array_keys( $this->get_order_statuses() );
		$admin     = $this->sanitize_status_selection( isset( $_POST['admin_statuses'] ) ? array_map( 'sanitize_key', (array) wp_unslash( $_POST['admin_statuses'] ) ) : array(), $available );
		$customer  = $this->sanitize_status_selection( isset( $_POST['customer_statuses'] ) ? array_map( 'sanitize_key', (array) wp_unslash( $_POST['customer_statuses'] ) ) : array(), $available );

		if ( empty( $admin ) && empty( $customer ) ) {
			return array(
				'type'     => 'error',
				'messages' => array( __( 'Select at least one order status.', 'inteltele' ) ),
			);
		}

		$saved = $this->get_settings_repository()->save_wc_statuses(
			array(
				'admin'    => $admin,
				'customer' => $customer,
			)
		);

		if ( ! $saved ) {
			return array(
				'type'     => 'error',
				'messages' => array( __( 'Settings could not be saved. Please try again.', 'inteltele' ) ),
			);
		}

		return array(
			'type'     => 'success',
			'messages' => array( __( 'Saved.', 'inteltele' ) ),
		);
	}

	/**
	 * Sanitize selected statuses.
	 *
	 * @param mixed    $raw Raw values.
	 * @param string[] $available Available statuses.
	 * @return string[]
	 */
	private function sanitize_status_selection( $raw, array $available ): array {
		$values = is_array( $raw ) ? $raw : array();
		$result = array();

		foreach ( $values as $value ) {
			$status = sanitize_key( $value );

			if ( in_array( $status, $available, true ) ) {
				$result[] = $status;
			}
		}

		return array_values( array_unique( $result ) );
	}

	/**
	 * Get settings repository.
	 */
	private function get_settings_repository(): \IntelTele\Repositories\SettingsRepository {
		static $repository = null;

		if ( null === $repository ) {
			$repository = new \IntelTele\Repositories\SettingsRepository();
		}

		return $repository;
	}

	/**
	 * Get WooCommerce statuses or fallback defaults.
	 *
	 * @return array<string,string>
	 */
	private function get_order_statuses(): array {
		if ( function_exists( 'wc_get_order_statuses' ) ) {
			return wc_get_order_statuses();
		}

		return array(
			'wc-pending'    => __( 'Pending payment', 'inteltele' ),
			'wc-processing' => __( 'Processing', 'inteltele' ),
			'wc-on-hold'    => __( 'On hold', 'inteltele' ),
			'wc-completed'  => __( 'Completed', 'inteltele' ),
			'wc-cancelled'  => __( 'Cancelled', 'inteltele' ),
			'wc-refunded'   => __( 'Refunded', 'inteltele' ),
			'wc-failed'     => __( 'Failed', 'inteltele' ),
		);
	}
}