//
// URI.h
//
// Library: Foundation
// Package: URI
// Module:  URI
//
// Definition of the URI class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#ifndef Foundation_URI_INCLUDED
#define Foundation_URI_INCLUDED


#include <utility>
#include <vector>
#include "Poco/Foundation.h"


namespace Poco
{


class Path;


class Foundation_API URI
/// A Uniform Resource Identifier, as specified in RFC 3986.
///
/// The URI class provides methods for building URIs from their
/// parts, as well as for splitting URIs into their parts.
/// Furthermore, the class provides methods for resolving
/// relative URIs against base URIs.
///
/// The class automatically performs a few normalizations on
/// all URIs and URI parts passed to it:
///   * scheme identifiers are converted to lower case
///   * percent-encoded characters are decoded (except for the query string)
///   * optionally, dot segments are removed from paths (see normalize())
///
/// Note that dealing with query strings requires some precautions, as, internally,
/// query strings are stored in percent-encoded form, while all other parts of the URI
/// are stored in decoded form. While parsing query strings from properly encoded URLs
/// generally works, explicitly setting query strings with setQuery() or extracting
/// query strings with getQuery() may lead to ambiguities. See the descriptions of
/// setQuery(), setRawQuery(), getQuery() and getRawQuery() for more information.
{
public:
    typedef std::vector<std::pair<std::string, std::string>> QueryParameters;

    URI();
    /// Creates an empty URI.

    explicit URI(const std::string & uri, bool enable_url_encoding = true);
    /// Parses an URI from the given string. Throws a
    /// SyntaxException if the uri is not valid.

    explicit URI(const char * uri);
    /// Parses an URI from the given string. Throws a
    /// SyntaxException if the uri is not valid.

    URI(const std::string & scheme, const std::string & pathEtc);
    /// Creates an URI from its parts.

    URI(const std::string & scheme, const std::string & authority, const std::string & pathEtc);
    /// Creates an URI from its parts.

    URI(const std::string & scheme, const std::string & authority, const std::string & path, const std::string & query);
    /// Creates an URI from its parts.

    URI(const std::string & scheme,
        const std::string & authority,
        const std::string & path,
        const std::string & query,
        const std::string & fragment);
    /// Creates an URI from its parts.

    URI(const URI & uri);
    /// Copy constructor. Creates an URI from another one.

    URI(const URI & baseURI, const std::string & relativeURI);
    /// Creates an URI from a base URI and a relative URI, according to
    /// the algorithm in section 5.2 of RFC 3986.

    explicit URI(const Path & path);
    /// Creates a URI from a path.
    ///
    /// The path will be made absolute, and a file:// URI
    /// will be built from it.

    ~URI();
    /// Destroys the URI.

    URI & operator=(const URI & uri);
    /// Assignment operator.

    URI & operator=(const std::string & uri);
    /// Parses and assigns an URI from the given string. Throws a
    /// SyntaxException if the uri is not valid.

    URI & operator=(const char * uri);
    /// Parses and assigns an URI from the given string. Throws a
    /// SyntaxException if the uri is not valid.

    void swap(URI & uri);
    /// Swaps the URI with another one.

    void clear();
    /// Clears all parts of the URI.

    std::string toString() const;
    /// Returns a string representation of the URI.
    ///
    /// Characters in the path, query and fragment parts will be
    /// percent-encoded as necessary.

    const std::string & getScheme() const;
    /// Returns the scheme part of the URI.

    void setScheme(const std::string & scheme);
    /// Sets the scheme part of the URI. The given scheme
    /// is converted to lower-case.
    ///
    /// A list of registered URI schemes can be found
    /// at <http://www.iana.org/assignments/uri-schemes>.

    const std::string & getUserInfo() const;
    /// Returns the user-info part of the URI.

    void setUserInfo(const std::string & userInfo);
    /// Sets the user-info part of the URI.

    const std::string & getHost() const;
    /// Returns the host part of the URI.

    void setHost(const std::string & host);
    /// Sets the host part of the URI.

    unsigned short getPort() const;
    /// Returns the port number part of the URI.
    ///
    /// If no port number (0) has been specified, the
    /// well-known port number (e.g., 80 for http) for
    /// the given scheme is returned if it is known.
    /// Otherwise, 0 is returned.

    void setPort(unsigned short port);
    /// Sets the port number part of the URI.

    std::string getAuthority() const;
    /// Returns the authority part (userInfo, host and port)
    /// of the URI.
    ///
    /// If the port number is a well-known port
    /// number for the given scheme (e.g., 80 for http), it
    /// is not included in the authority.

    void setAuthority(const std::string & authority);
    /// Parses the given authority part for the URI and sets
    /// the user-info, host, port components accordingly.

    const std::string & getPath() const;
    /// Returns the decoded path part of the URI.

    void setPath(const std::string & path);
    /// Sets the path part of the URI.

    std::string getQuery() const;
    /// Returns the decoded query part of the URI.
    ///
    /// Note that encoded ampersand characters ('&', "%26")
    /// will be decoded, which could cause ambiguities if the query
    /// string contains multiple parameters and a parameter name
    /// or value contains an ampersand as well.
    /// In such a case it's better to use getRawQuery() or
    /// getQueryParameters().

    void setQuery(const std::string & query);
    /// Sets the query part of the URI.
    ///
    /// The query string will be percent-encoded. If the query
    /// already contains percent-encoded characters, these
    /// will be double-encoded, which is probably not what's
    /// intended by the caller. Furthermore, ampersand ('&')
    /// characters in the query will not be encoded. This could
    /// lead to ambiguity issues if the query string contains multiple
    /// name-value parameters separated by ampersand, and if any
    /// name or value also contains an ampersand. In such a
    /// case, it's better to use setRawQuery() with a properly
    /// percent-encoded query string, or use addQueryParameter()
    /// or setQueryParameters(), which take care of appropriate
    /// percent encoding of parameter names and values.

    void addQueryParameter(const std::string & param, const std::string & val = "");
    /// Adds "param=val" to the query; "param" may not be empty.
    /// If val is empty, only '=' is appended to the parameter.
    ///
    /// In addition to regular encoding, function also encodes '&' and '=',
    /// if found in param or val.

    const std::string & getRawQuery() const;
    /// Returns the query string in raw form, which usually
    /// means percent encoded.

    void setRawQuery(const std::string & query);
    /// Sets the query part of the URI.
    ///
    /// The given query string must be properly percent-encoded.

    QueryParameters getQueryParameters() const;
    /// Returns the decoded query string parameters as a vector
    /// of name-value pairs.

    void setQueryParameters(const QueryParameters & params);
    /// Sets the query part of the URI from a vector
    /// of query parameters.
    ///
    /// Calls addQueryParameter() for each parameter name and value.

    const std::string & getFragment() const;
    /// Returns the fragment part of the URI.

    void setFragment(const std::string & fragment);
    /// Sets the fragment part of the URI.

    void setPathEtc(const std::string & pathEtc);
    /// Sets the path, query and fragment parts of the URI.

    std::string getPathEtc() const;
    /// Returns the encoded path, query and fragment parts of the URI.

    std::string getPathAndQuery() const;
    /// Returns the encoded path and query parts of the URI.

    void resolve(const std::string & relativeURI);
    /// Resolves the given relative URI against the base URI.
    /// See section 5.2 of RFC 3986 for the algorithm used.

    void resolve(const URI & relativeURI);
    /// Resolves the given relative URI against the base URI.
    /// See section 5.2 of RFC 3986 for the algorithm used.

    bool isRelative() const;
    /// Returns true if the URI is a relative reference, false otherwise.
    ///
    /// A relative reference does not contain a scheme identifier.
    /// Relative references are usually resolved against an absolute
    /// base reference.

    bool empty() const;
    /// Returns true if the URI is empty, false otherwise.

    bool operator==(const URI & uri) const;
    /// Returns true if both URIs are identical, false otherwise.
    ///
    /// Two URIs are identical if their scheme, authority,
    /// path, query and fragment part are identical.

    bool operator==(const std::string & uri) const;
    /// Parses the given URI and returns true if both URIs are identical,
    /// false otherwise.

    bool operator!=(const URI & uri) const;
    /// Returns true if both URIs are identical, false otherwise.

    bool operator!=(const std::string & uri) const;
    /// Parses the given URI and returns true if both URIs are identical,
    /// false otherwise.

    void normalize();
    /// Normalizes the URI by removing all but leading . and .. segments from the path.
    ///
    /// If the first path segment in a relative path contains a colon (:),
    /// such as in a Windows path containing a drive letter, a dot segment (./)
    /// is prepended in accordance with section 3.3 of RFC 3986.

    void getPathSegments(std::vector<std::string> & segments);
    /// Places the single path segments (delimited by slashes) into the
    /// given vector.

    static void encode(const std::string & str, const std::string & reserved, std::string & encodedStr);
    /// URI-encodes the given string by escaping reserved and non-ASCII
    /// characters. The encoded string is appended to encodedStr.

    static void decode(const std::string & str, std::string & decodedStr, bool plusAsSpace = false);
    /// URI-decodes the given string by replacing percent-encoded
    /// characters with the actual character. The decoded string
    /// is appended to decodedStr.
    ///
    /// When plusAsSpace is true, non-encoded plus signs in the query are decoded as spaces.
    /// (http://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.1)

protected:
    bool equals(const URI & uri) const;
    /// Returns true if both uri's are equivalent.

    bool isWellKnownPort() const;
    /// Returns true if the URI's port number is a well-known one
    /// (for example, 80, if the scheme is http).

    unsigned short getWellKnownPort() const;
    /// Returns the well-known port number for the URI's scheme,
    /// or 0 if the port number is not known.

    void parse(const std::string & uri);
    /// Parses and assigns an URI from the given string. Throws a
    /// SyntaxException if the uri is not valid.

    void parseAuthority(std::string::const_iterator & it, const std::string::const_iterator & end);
    /// Parses and sets the user-info, host and port from the given data.

    void parseHostAndPort(std::string::const_iterator & it, const std::string::const_iterator & end);
    /// Parses and sets the host and port from the given data.

    void parsePath(std::string::const_iterator & it, const std::string::const_iterator & end);
    /// Parses and sets the path from the given data.

    void parsePathEtc(std::string::const_iterator & it, const std::string::const_iterator & end);
    /// Parses and sets the path, query and fragment from the given data.

    void parseQuery(std::string::const_iterator & it, const std::string::const_iterator & end);
    /// Parses and sets the query from the given data.

    void parseFragment(std::string::const_iterator & it, const std::string::const_iterator & end);
    /// Parses and sets the fragment from the given data.

    void mergePath(const std::string & path);
    /// Appends a path to the URI's path.

    void removeDotSegments(bool removeLeading = true);
    /// Removes all dot segments from the path.

    static void getPathSegments(const std::string & path, std::vector<std::string> & segments);
    /// Places the single path segments (delimited by slashes) into the
    /// given vector.

    void buildPath(const std::vector<std::string> & segments, bool leadingSlash, bool trailingSlash);
    /// Builds the path from the given segments.

    static const std::string RESERVED_PATH;
    static const std::string RESERVED_QUERY;
    static const std::string RESERVED_QUERY_PARAM;
    static const std::string RESERVED_FRAGMENT;
    static const std::string ILLEGAL;

private:
    void encodePath(std::string & encodedStr) const;
    void decodePath(const std::string & encodedStr);


    std::string _scheme;
    std::string _userInfo;
    std::string _host;
    unsigned short _port;
    std::string _path;
    std::string _query;
    std::string _fragment;

    bool _enable_url_encoding = true;
};


//
// inlines
//
inline const std::string & URI::getScheme() const
{
    return _scheme;
}


inline const std::string & URI::getUserInfo() const
{
    return _userInfo;
}


inline const std::string & URI::getHost() const
{
    return _host;
}


inline const std::string & URI::getPath() const
{
    return _path;
}


inline const std::string & URI::getRawQuery() const
{
    return _query;
}


inline const std::string & URI::getFragment() const
{
    return _fragment;
}


inline void swap(URI & u1, URI & u2)
{
    u1.swap(u2);
}


} // namespace Poco


#endif // Foundation_URI_INCLUDED