<?php

declare(strict_types=1);

/**
 * This file is part of CodeIgniter 4 framework.
 *
 * (c) CodeIgniter Foundation <admin@codeigniter.com>
 *
 * For the full copyright and license information, please view
 * the LICENSE file that was distributed with this source code.
 */

namespace CodeIgniter\HTTP;

use Config\UserAgents;
use Stringable;

/**
 * Abstraction for an HTTP user agent
 *
 * @see \CodeIgniter\HTTP\UserAgentTest
 */
class UserAgent implements Stringable
{
 /**
 * Current user-agent
 *
 * @var string
 */
 protected $agent = '';

 /**
 * Flag for if the user-agent belongs to a browser
 *
 * @var bool
 */
 protected $isBrowser = false;

 /**
 * Flag for if the user-agent is a robot
 *
 * @var bool
 */
 protected $isRobot = false;

 /**
 * Flag for if the user-agent is a mobile browser
 *
 * @var bool
 */
 protected $isMobile = false;

 /**
 * Holds the config file contents.
 *
 * @var UserAgents
 */
 protected $config;

 /**
 * Current user-agent platform
 *
 * @var string
 */
 protected $platform = '';

 /**
 * Current user-agent browser
 *
 * @var string
 */
 protected $browser = '';

 /**
 * Current user-agent version
 *
 * @var string
 */
 protected $version = '';

 /**
 * Current user-agent mobile name
 *
 * @var string
 */
 protected $mobile = '';

 /**
 * Current user-agent robot name
 *
 * @var string
 */
 protected $robot = '';

 /**
 * HTTP Referer
 *
 * @var bool|string|null
 */
 protected $referrer;

 /**
 * Constructor
 *
 * Sets the User Agent and runs the compilation routine
 */
 public function __construct(?UserAgents $config = null)
 {
 $this->config = $config ?? config(UserAgents::class);

 $userAgent = service('superglobals')->server('HTTP_USER_AGENT');

 if ($userAgent !== null) {
 $this->agent = trim($userAgent);
 $this->compileData();
 }
 }

 /**
 * Is Browser
 */
 public function isBrowser(?string $key = null): bool
 {
 if (! $this->isBrowser) {
 return false;
 }

 // No need to be specific, it's a browser
 if ((string) $key === '') {
 return true;
 }

 // Check for a specific browser
 return isset($this->config->browsers[$key]) && $this->browser === $this->config->browsers[$key];
 }

 /**
 * Is Robot
 */
 public function isRobot(?string $key = null): bool
 {
 if (! $this->isRobot) {
 return false;
 }

 // No need to be specific, it's a robot
 if ((string) $key === '') {
 return true;
 }

 // Check for a specific robot
 return isset($this->config->robots[$key]) && $this->robot === $this->config->robots[$key];
 }

 /**
 * Is Mobile
 */
 public function isMobile(?string $key = null): bool
 {
 if (! $this->isMobile) {
 return false;
 }

 // No need to be specific, it's a mobile
 if ((string) $key === '') {
 return true;
 }

 // Check for a specific robot
 return isset($this->config->mobiles[$key]) && $this->mobile === $this->config->mobiles[$key];
 }

 /**
 * Is this a referral from another site?
 */
 public function isReferral(): bool
 {
 if (! isset($this->referrer)) {
 $referer = service('superglobals')->server('HTTP_REFERER');
 if ($referer === null || $referer === '') {
 $this->referrer = false;
 } else {
 $refererHost = @parse_url($referer, PHP_URL_HOST);
 $ownHost = parse_url(\base_url(), PHP_URL_HOST);

 $this->referrer = ($refererHost && $refererHost !== $ownHost);
 }
 }

 return $this->referrer;
 }

 /**
 * Agent String
 */
 public function getAgentString(): string
 {
 return $this->agent;
 }

 /**
 * Get Platform
 */
 public function getPlatform(): string
 {
 return $this->platform;
 }

 /**
 * Get Browser Name
 */
 public function getBrowser(): string
 {
 return $this->browser;
 }

 /**
 * Get the Browser Version
 */
 public function getVersion(): string
 {
 return $this->version;
 }

 /**
 * Get The Robot Name
 */
 public function getRobot(): string
 {
 return $this->robot;
 }

 /**
 * Get the Mobile Device
 */
 public function getMobile(): string
 {
 return $this->mobile;
 }

 /**
 * Get the referrer
 */
 public function getReferrer(): string
 {
 $referrer = service('superglobals')->server('HTTP_REFERER');

 return $referrer === null ? '' : trim($referrer);
 }

 /**
 * Parse a custom user-agent string
 *
 * @return void
 */
 public function parse(string $string)
 {
 // Reset values
 $this->isBrowser = false;
 $this->isRobot = false;
 $this->isMobile = false;
 $this->browser = '';
 $this->version = '';
 $this->mobile = '';
 $this->robot = '';

 // Set the new user-agent string and parse it, unless empty
 $this->agent = $string;

 if ($string !== '') {
 $this->compileData();
 }
 }

 /**
 * Compile the User Agent Data
 *
 * @return void
 */
 protected function compileData()
 {
 $this->setPlatform();

 foreach (['setRobot', 'setBrowser', 'setMobile'] as $function) {
 if ($this->{$function}()) {
 break;
 }
 }
 }

 /**
 * Set the Platform
 */
 protected function setPlatform(): bool
 {
 if (is_array($this->config->platforms) && $this->config->platforms !== []) {
 foreach ($this->config->platforms as $key => $val) {
 if (preg_match('|' . preg_quote($key, '|') . '|i', $this->agent)) {
 $this->platform = $val;

 return true;
 }
 }
 }

 $this->platform = 'Unknown Platform';

 return false;
 }

 /**
 * Set the Browser
 */
 protected function setBrowser(): bool
 {
 if (is_array($this->config->browsers) && $this->config->browsers !== []) {
 foreach ($this->config->browsers as $key => $val) {
 if (preg_match('|' . $key . '.*?([0-9\.]+)|i', $this->agent, $match)) {
 $version = $match[1];

 // Safari's browser version is reported in the Version token.
 if ($val === 'Safari' && preg_match('|Version/([0-9\.]+).*?Safari|i', $this->agent, $safariMatch)) {
 $version = $safariMatch[1];
 }

 $this->isBrowser = true;
 $this->version = $version;
 $this->browser = $val;
 $this->setMobile();

 return true;
 }
 }
 }

 return false;
 }

 /**
 * Set the Robot
 */
 protected function setRobot(): bool
 {
 if (is_array($this->config->robots) && $this->config->robots !== []) {
 foreach ($this->config->robots as $key => $val) {
 if (preg_match('|' . preg_quote($key, '|') . '|i', $this->agent)) {
 $this->isRobot = true;
 $this->robot = $val;
 $this->setMobile();

 return true;
 }
 }
 }

 return false;
 }

 /**
 * Set the Mobile Device
 */
 protected function setMobile(): bool
 {
 if (is_array($this->config->mobiles) && $this->config->mobiles !== []) {
 foreach ($this->config->mobiles as $key => $val) {
 if (false !== (stripos($this->agent, $key))) {
 $this->isMobile = true;
 $this->mobile = $val;

 return true;
 }
 }
 }

 return false;
 }

 /**
 * Outputs the original Agent String when cast as a string.
 */
 public function __toString(): string
 {
 return $this->getAgentString();
 }
}