<?php

use SMW\Encoder;
use SMW\Message;

/**
 * @ingroup SMWDataValues
 */

define( 'SMW_URI_MODE_EMAIL', 1 );
define( 'SMW_URI_MODE_URI', 3 );
define( 'SMW_URI_MODE_ANNOURI', 4 );
define( 'SMW_URI_MODE_TEL', 5 );

/**
 * This datavalue implements URL/URI/ANNURI/PHONE/EMAIL datavalues suitable for
 * defining the respective types of properties.
 *
 * @author Nikolas Iwan
 * @author Markus Krötzsch
 * @ingroup SMWDataValues
 * @bug Correctly create safe HTML and Wiki text.
 */
class SMWURIValue extends SMWDataValue {

	/**
	 * Raw value without encoding
	 */
	const VALUE_RAW = 'uri.value.raw';

	/**
	 * The value as returned by getWikitext() and getLongText().
	 * @var string
	 */
	protected $m_wikitext;
	/**
	 * One of the basic modes of operation for this class (emails, URL,
	 * telephone number URI, ...).
	 * @var integer
	 */
	private $m_mode;

	/**
	 * @var boolean
	 */
	private $showUrlContextInRawFormat = true;

	/**
	 * @var array
	 */
	private $schemeList = [];

	public function __construct( $typeid ) {
		parent::__construct( $typeid );
		switch ( $typeid ) {
			case '_ema':
				$this->m_mode = SMW_URI_MODE_EMAIL;
			break;
			case '_anu':
				$this->m_mode = SMW_URI_MODE_ANNOURI;
			break;
			case '_tel':
				$this->m_mode = SMW_URI_MODE_TEL;
			break;
			case '__spu':
			case '_uri':
			case '_url':
			default:
				$this->m_mode = SMW_URI_MODE_URI;
			break;
		}

		$this->schemeList = array_flip( $GLOBALS['smwgURITypeSchemeList'] );
	}

	protected function parseUserValue( $value ) {
		$value = trim( $value );
		$this->m_wikitext = $value;
		if ( $this->m_caption === false ) {
			$this->m_caption = $this->m_wikitext;
		}

		$scheme = $hierpart = $query = $fragment = '';
		if ( $value === '' ) { // do not accept empty strings
			$this->addErrorMsg( [ 'smw_emptystring' ] );
			return;
		}

		switch ( $this->m_mode ) {
			case SMW_URI_MODE_URI:
			case SMW_URI_MODE_ANNOURI:

				// Whether the url value was externally encoded or not
				if ( strpos( $value, "%" ) === false ) {
					$this->showUrlContextInRawFormat = false;
				}

				// If somehow the slash was encoded bring into one format
				$value = str_replace( "%2F", "/", $value );

				$parts = explode( ':', $value, 2 ); // try to split "schema:rest"
				if ( count( $parts ) == 1 ) { // possibly add "http" as default
					$value = 'http://' . $value;
					$parts[1] = $parts[0];
					$parts[0] = 'http';
				}
				// check against blacklist
				$uri_blacklist = explode( "\n", Message::get( 'smw_uri_blacklist', Message::TEXT, Message::CONTENT_LANGUAGE ) );
				foreach ( $uri_blacklist as $uri ) {
					$uri = trim( $uri );
					if ( $uri !== '' && $uri == mb_substr( $value, 0, mb_strlen( $uri ) ) ) { // disallowed URI!
						$this->addErrorMsg( [ 'smw_baduri', $value ] );
						return;
					}
				}
				// decompose general URI components
				$scheme = $parts[0];

				if ( !$this->getOption( self::OPT_QUERY_CONTEXT ) && !isset( $this->schemeList[$scheme] ) ) {
					$this->addErrorMsg( [ 'smw-datavalue-uri-invalid-scheme', $scheme ] );
					return;
				}

				$parts = explode( '?', $parts[1], 2 ); // try to split "hier-part?queryfrag"
				if ( count( $parts ) == 2 ) {
					$hierpart = $parts[0];
					$parts = explode( '#', $parts[1], 2 ); // try to split "query#frag"
					$query = $parts[0];
					$fragment = ( count( $parts ) == 2 ) ? $parts[1] : '';
				} else {
					$query = '';
					$parts = explode( '#', $parts[0], 2 ); // try to split "hier-part#frag"
					$hierpart = $parts[0];
					$fragment = ( count( $parts ) == 2 ) ? $parts[1] : '';
				}
				// We do not validate the URI characters (the data item will do this) but we do some escaping:
				// encode most characters, but leave special symbols as given by user:
				$hierpart = str_replace( [ '%3A', '%2F', '%23', '%40', '%3F', '%3D', '%26', '%25' ], [ ':', '/', '#', '@', '?', '=', '&', '%' ], rawurlencode( $hierpart ) );
				$query = str_replace( [ '%3A', '%2F', '%23', '%40', '%3F', '%3D', '%26', '%25' ], [ ':', '/', '#', '@', '?', '=', '&', '%' ], rawurlencode( $query ) );
				$fragment = str_replace( [ '%3A', '%2F', '%23', '%40', '%3F', '%3D', '%26', '%25' ], [ ':', '/', '#', '@', '?', '=', '&', '%' ], rawurlencode( $fragment ) );
				/// NOTE: we do not support raw [ (%5D) and ] (%5E), although they are needed for ldap:// (but rarely in a wiki)
				/// NOTE: "+" gets encoded, as it is interpreted as space by most browsers when part of a URL;
				///       this prevents tel: from working directly, but we have a datatype for this anyway.

				if ( substr( $hierpart, 0, 2 ) === '//' ) {
					$hierpart = substr( $hierpart, 2 );
				}

				// #3540
				if ( $hierpart !== '' && $hierpart[0] === '/' ) {
					return $this->addErrorMsg( [ 'smw-datavalue-uri-invalid-authority-path-component', $value, $hierpart ] );
				}

				break;
			case SMW_URI_MODE_TEL:
				$scheme = 'tel';

				if ( substr( $value, 0, 4 ) === 'tel:' ) { // accept optional "tel"
					$value = substr( $value, 4 );
					$this->m_wikitext = $value;
				}

				$hierpart = preg_replace( '/(?<=[0-9]) (?=[0-9])/', '\1-\2', $value );
				$hierpart = str_replace( ' ', '', $hierpart );
				if ( substr( $hierpart, 0, 2 ) == '00' ) {
					$hierpart = '+' . substr( $hierpart, 2 );
				}

				if ( !$this->getOption( self::OPT_QUERY_CONTEXT ) && ( ( strlen( preg_replace( '/[^0-9]/', '', $hierpart ) ) < 6 ) ||
					( preg_match( '<[-+./][-./]>', $hierpart ) ) ||
					( !self::isValidTelURI( 'tel:' . $hierpart ) ) ) ) { /// TODO: introduce error-message for "bad" phone number
					$this->addErrorMsg( [ 'smw_baduri', $this->m_wikitext ] );
					return;
				}
				break;
			case SMW_URI_MODE_EMAIL:
				$scheme = 'mailto';
				if ( strpos( $value, 'mailto:' ) === 0 ) { // accept optional "mailto"
					$value = substr( $value, 7 );
					$this->m_wikitext = $value;
				}

				if ( !$this->getOption( self::OPT_QUERY_CONTEXT ) && !Sanitizer::validateEmail( $value ) ) {
					/// TODO: introduce error-message for "bad" email
					$this->addErrorMsg( [ 'smw_baduri', $value ] );
					return;
				}
				$hierpart = str_replace( [ '%3A', '%2F', '%23', '%40', '%3F', '%3D', '%26', '%25' ], [ ':', '/', '#', '@', '?', '=', '&', '%' ], rawurlencode( $value ) );
		}

		// Now create the URI data item:
		try {
			$this->m_dataitem = new SMWDIUri( $scheme, $hierpart, $query, $fragment, !$this->getOption( self::OPT_QUERY_CONTEXT ) );
		} catch ( SMWDataItemException $e ) {
			$this->addErrorMsg( [ 'smw_baduri', $this->m_wikitext ] );
		}
	}

	/**
	 * Returns true if the argument is a valid RFC 3966 phone number.
	 * Only global phone numbers are supported, and no full validation
	 * of parameters (appended via ;param=value) is performed.
	 */
	protected static function isValidTelURI( $s ) {
		$tel_uri_regex = '<^tel:\+[0-9./-]*[0-9][0-9./-]*(;[0-9a-zA-Z-]+=(%[0-9a-zA-Z][0-9a-zA-Z]|[0-9a-zA-Z._~:/?#[\]@!$&\'()*+,;=-])*)*$>';
		return (bool) preg_match( $tel_uri_regex, $s );
	}

	/**
	 * @see SMWDataValue::loadDataItem()
	 * @param $dataitem SMWDataItem
	 * @return boolean
	 */
	protected function loadDataItem( SMWDataItem $dataItem ) {

		if ( $dataItem->getDIType() !== SMWDataItem::TYPE_URI ) {
			return false;
		}

		$this->m_dataitem = $dataItem;
		if ( $this->m_mode == SMW_URI_MODE_EMAIL ) {
			$this->m_wikitext = substr( $dataItem->getURI(), 7 );
		} elseif ( $this->m_mode == SMW_URI_MODE_TEL ) {
			$this->m_wikitext = substr( $dataItem->getURI(), 4 );
		} else {
			$this->m_wikitext = $dataItem->getURI();
		}

		$this->m_caption = $this->m_wikitext;
		$this->showUrlContextInRawFormat = false;

		return true;
	}

	public function getShortWikiText( $linked = null ) {

		list( $url, $caption ) = $this->decodeUriContext( $this->m_caption, $linked );

		if ( is_null( $linked ) || ( $linked === false ) || ( $url === '' ) ||
			( $this->m_outformat == '-' ) || ( $this->m_caption === '' ) ) {
			return $caption;
		} elseif ( $this->m_outformat == 'nowiki' ) {
			return $this->makeNonlinkedWikiText( $caption );
		} else {
			return '[' . $url . ' ' . $caption . ']';
		}
	}

	public function getShortHTMLText( $linker = null ) {

		list( $url, $caption ) = $this->decodeUriContext( $this->m_caption, $linker );

		if ( is_null( $linker ) || ( !$this->isValid() ) || ( $url === '' ) ||
			( $this->m_outformat == '-' ) || ( $this->m_outformat == 'nowiki' ) ||
			( $this->m_caption === '' ) || $linker === false ) {
			return $caption;
		} else {
			return $linker->makeExternalLink( $url, $caption );
		}
	}

	public function getLongWikiText( $linked = null ) {

		if ( !$this->isValid() ) {
			return $this->getErrorText();
		}

		list( $url, $wikitext ) = $this->decodeUriContext( $this->m_wikitext, $linked );

		if ( is_null( $linked ) || ( $linked === false ) || ( $url === '' ) ||
			( $this->m_outformat == '-' ) || $linked === false ) {
			return $wikitext;
		} elseif ( $this->m_outformat == 'nowiki' ) {
			return $this->makeNonlinkedWikiText( $wikitext );
		} else {
			return '[' . $url . ' ' . $wikitext . ']';
		}
	}

	public function getLongHTMLText( $linker = null ) {

		if ( !$this->isValid() ) {
			return $this->getErrorText();
		}

		list( $url, $wikitext ) = $this->decodeUriContext( $this->m_wikitext, $linker );

		if ( is_null( $linker ) || ( !$this->isValid() ) || ( $url === '' ) ||
			( $this->m_outformat == '-' ) || ( $this->m_outformat == 'nowiki' ) || $linker === false ) {
			return $wikitext;
		} else {
			return $linker->makeExternalLink( $url, $wikitext );
		}
	}

	public function getWikiValue() {

		if ( $this->getOption( self::VALUE_RAW ) ) {
			return rawurldecode( $this->m_wikitext );
		}

		return $this->m_wikitext;
	}

	public function getURI() {
		return $this->getUriDataitem()->getURI();
	}

	protected function getServiceLinkParams() {
		// Create links to mapping services based on a wiki-editable message. The parameters
		// available to the message are:
		// $1: urlencoded version of URI/URL value (includes mailto: for emails)
		return [ rawurlencode( $this->getUriDataitem()->getURI() ) ];
	}

	/**
	 * Get a URL for hyperlinking this URI, or the empty string if this URI
	 * is not hyperlinked in MediaWiki.
	 * @return string
	 */
	public function getURL() {
		global $wgUrlProtocols;

		foreach ( $wgUrlProtocols as $prot ) {
			if ( ( $prot == $this->getUriDataitem()->getScheme() . ':' ) || ( $prot == $this->getUriDataitem()->getScheme() . '://' ) ) {
				return $this->getUriDataitem()->getURI();
			}
		}

		return '';
	}

	/**
	 * Helper function to get the current dataitem, or some dummy URI
	 * dataitem if the dataitem was not set. This makes it easier to
	 * write code that avoids errors even if the data was not
	 * initialized properly.
	 * @return SMWDIUri
	 */
	protected function getUriDataitem() {
		if ( isset( $this->m_dataitem ) ) {
			return $this->m_dataitem;
		} else { // note: use "noprotocol" to avoid accidental use in an MW link, see getURL()
			return new SMWDIUri( 'noprotocol', 'x', '', '', $this->m_typeid );
		}
	}

	/**
	 * Helper function that changes a URL string in such a way that it
	 * can be used in wikitext without being turned into a hyperlink,
	 * while still displaying the same characters. The use of
	 * &lt;nowiki&gt; is avoided, since the resulting strings may be
	 * inserted during parsing, after this has been stripped.
	 *
	 * @since 1.8
	 */
	protected function makeNonlinkedWikiText( $url ) {
		return str_replace( ':', '&#58;', $url );
	}

	private function decodeUriContext( $context, $linker ) {

		// Prior to decoding turn any `-` into an internal representation to avoid
		// potential breakage
		if ( !$this->showUrlContextInRawFormat ) {
			$context = Encoder::decode( str_replace( '-', '-2D', $context ) );
		}

		if ( $this->m_mode !== SMW_URI_MODE_EMAIL && $linker !== null ) {
			$context = str_replace( '_', ' ', $context );
		}

		// Allow the display without `_` so that URIs can be split
		// during the outout by the browser without breaking the URL itself
		// as it contains the `_` for spaces
		return [ $this->getURL(), $context ];
	}

}