<?php
namespace Consiva\Consent\Scan;

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

use Consiva\Consent\Api\ConsivaClient;
use Consiva\Consent\Support\State;
use WP_Error;

/**
 * Verification re-scan results (Plugin §6.4, WP-F10, Runtime §4.5).
 *
 * After activation Consiva re-crawls a sample of pages before a choice, after Reject All and after
 * Accept All, and reports per technology whether it really waits for consent.
 *
 * The re-scan is real: activating or publishing returns verification_scan_id (verificationScanId on a
 * config PATCH), a normal scan with trigger "config_change". The per-technology results are NOT
 * documented by Consiva yet: if the finished scan carries verification[] of
 * { technology, category, state, pages[], note } they are shown; otherwise "detailed" is false and the
 * screen only says the re-scan finished.
 */
final class Verification {

	const CACHE     = 'consiva_consent_verification_view';
	const CACHE_TTL = 900;

	const STATES = array(
		'fires_pre_consent_CONFLICT',
		'verified_fires_only_after_consent',
		'verified_blocked',
		'not_observed',
	);

	/**
	 * View of the latest verification, or array( 'status' => 'none' ) before the first one.
	 *
	 * @return array<string,mixed>|WP_Error
	 */
	public static function current() {
		$scan_id = (string) State::get( 'verification_scan_id' );
		if ( '' === $scan_id ) {
			return array( 'status' => 'none' );
		}

		$cached = get_transient( self::CACHE );
		if ( is_array( $cached ) && isset( $cached['scan_id'] ) && $cached['scan_id'] === $scan_id ) {
			return $cached;
		}

		$response = ( new ConsivaClient() )->get_scan( $scan_id );
		if ( is_wp_error( $response ) ) {
			return $response;
		}
		$view = self::view( $response['body'], $scan_id );
		if ( $view['done'] ) {
			set_transient( self::CACHE, $view, self::CACHE_TTL ); // A finished verification never changes.
		}
		return $view;
	}

	/**
	 * @return void
	 */
	public static function clear_cache() {
		delete_transient( self::CACHE );
	}

	/**
	 * Allowlisted view of a verification scan.
	 *
	 * @param array<string,mixed> $scan    Decoded scan response.
	 * @param string              $scan_id Scan ID.
	 * @return array<string,mixed>
	 */
	public static function view( array $scan, $scan_id ) {
		$status  = isset( $scan['status'] ) && in_array( $scan['status'], ScanProgress::STATUSES, true ) ? $scan['status'] : 'queued';
		$results = array();
		$counts  = array_fill_keys( self::STATES, 0 );

		foreach ( isset( $scan['verification'] ) && is_array( $scan['verification'] ) ? $scan['verification'] : array() as $row ) {
			if ( ! is_array( $row ) || ! isset( $row['state'] ) || ! in_array( $row['state'], self::STATES, true ) ) {
				continue;
			}
			$pages = array();
			foreach ( isset( $row['pages'] ) && is_array( $row['pages'] ) ? array_slice( $row['pages'], 0, 10 ) : array() as $path ) {
				// Paths only: the admin screen links them to this site, never to another host.
				if ( is_string( $path ) && '/' === substr( $path, 0, 1 ) && '//' !== substr( $path, 0, 2 ) ) {
					$pages[] = sanitize_text_field( $path );
				}
			}
			$results[] = array(
				'technology' => isset( $row['technology'] ) && is_string( $row['technology'] ) ? sanitize_text_field( $row['technology'] ) : __( 'Unknown technology', 'consiva-ai' ),
				'category'   => isset( $row['category'] ) ? sanitize_key( (string) $row['category'] ) : '',
				'state'      => $row['state'],
				'pages'      => $pages,
				'note'       => isset( $row['note'] ) && is_string( $row['note'] ) ? sanitize_text_field( $row['note'] ) : '',
			);
			++$counts[ $row['state'] ];
		}

		// Conflicts first: they are the reason this screen exists.
		usort(
			$results,
			static function ( $a, $b ) {
				$by_state = array_search( $a['state'], self::STATES, true ) - array_search( $b['state'], self::STATES, true );
				return 0 !== $by_state ? $by_state : strcasecmp( $a['technology'], $b['technology'] );
			}
		);

		return array(
			'scan_id'      => $scan_id,
			'status'       => $status,
			'done'         => in_array( $status, ScanProgress::DONE_STATUSES, true ),
			'completed_at' => isset( $scan['completed_at'] ) && is_string( $scan['completed_at'] ) ? sanitize_text_field( $scan['completed_at'] ) : '',
			'detailed'     => isset( $scan['verification'] ) && is_array( $scan['verification'] ),
			'results'      => $results,
			'counts'       => $counts,
		);
	}
}