//! URIs, Relative References, and URI References

//!

//! See [RFC3986](https://tools.ietf.org/html/rfc3986).

//!

//! This module is composed of three primary types [`URI`], [`RelativeReference`], and

//! [`URIReference`] that are all very similar. The first thing to note is that URIs and relative

//! references are types of URI references. They differ in only one way: URIs have schemes, while

//! relative references do not.

//!

//! As a result, choose the type that best fits your use case. If you need absolute URIs, you should

//! use [`URI`], but if you want relative references (e.g. `"/"` in a GET request) use

//! [`RelativeReference`]. If you can accept both, then use [`URIReference`].


use std::convert::{Infallible, TryFrom};
use std::error::Error;
use std::fmt::{self, Display, Formatter};

use crate::authority::{Authority, AuthorityError, Host, Password, Username};
use crate::fragment::{Fragment, FragmentError};
use crate::path::{Path, PathError};
use crate::query::{Query, QueryError};
use crate::scheme::{Scheme, SchemeError};
use crate::uri_reference::{URIReference, URIReferenceBuilder, URIReferenceError};

/// A Uniform Resource Identifier (URI) as defined in

/// [RFC3986](https://tools.ietf.org/html/rfc3986).

///

/// A URI is a URI reference, one with a scheme.

#[derive(Clone, Debug, Eq, Hash, PartialEq)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
pub struct URI<'uri> {
    /// All URIs are also URI references, so we just maintain a [`URIReference`] underneath.

    uri_reference: URIReference<'uri>,
}

impl<'uri> URI<'uri> {
    pub fn as_uri_reference(&self) -> &URIReference<'uri> {
        &self.uri_reference
    }

    /// Returns the authority, if present, of the URI.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://example.com:80/my/path").unwrap();

    /// assert_eq!(uri.authority().unwrap().to_string(), "example.com:80");

    /// ```

    pub fn authority(&self) -> Option<&Authority<'uri>> {
        self.uri_reference.authority()
    }

    /// Constructs a default builder for a URI.

    ///

    /// This provides an alternative means of constructing a URI besides parsing and

    /// [`URI::from_parts`].

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Authority, Path, Scheme, URI};

    ///

    /// let uri = URI::builder()

    ///     .with_scheme(Scheme::HTTP)

    ///     .with_authority(Some(Authority::try_from("example.com").unwrap()))

    ///     .with_path(Path::try_from("/my/path").unwrap())

    ///     .build()

    ///     .unwrap();

    /// assert_eq!(uri.to_string(), "http://example.com/my/path");

    /// ```

    pub fn builder<'new_uri>() -> URIBuilder<'new_uri> {
        URIBuilder::new()
    }

    /// Returns whether the URI can act as a base URI.

    ///

    /// A URI can be a base if it is absolute (i.e. it has no fragment component).

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://example.com/my/path").unwrap();

    /// assert!(uri.can_be_a_base());

    ///

    /// let uri = URI::try_from("ftp://127.0.0.1#fragment").unwrap();

    /// assert!(!uri.can_be_a_base());

    /// ```

    pub fn can_be_a_base(&self) -> bool {
        !self.uri_reference.has_fragment()
    }

    /// Constructs a new [`URI`] from the individual parts: scheme, authority, path, query, and

    /// fragment.

    ///

    /// The lifetime used by the resulting value will be the lifetime of the part that is most

    /// restricted in scope.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Fragment, URI};

    ///

    /// let uri = URI::from_parts(

    ///     "http",

    ///     Some("example.com"),

    ///     "",

    ///     Some("query"),

    ///     None::<Fragment>

    /// ).unwrap();

    /// assert_eq!(uri.to_string(), "http://example.com/?query");

    /// ```

    pub fn from_parts<
        'new_uri,
        TScheme,
        TAuthority,
        TPath,
        TQuery,
        TFragment,
        TSchemeError,
        TAuthorityError,
        TPathError,
        TQueryError,
        TFragmentError,
    >(
        scheme: TScheme,
        authority: Option<TAuthority>,
        path: TPath,
        query: Option<TQuery>,
        fragment: Option<TFragment>,
    ) -> Result<URI<'new_uri>, URIError>
    where
        Scheme<'new_uri>: TryFrom<TScheme, Error = TSchemeError>,
        Authority<'new_uri>: TryFrom<TAuthority, Error = TAuthorityError>,
        Path<'new_uri>: TryFrom<TPath, Error = TPathError>,
        Query<'new_uri>: TryFrom<TQuery, Error = TQueryError>,
        Fragment<'new_uri>: TryFrom<TFragment, Error = TFragmentError>,
        URIReferenceError: From<TSchemeError>
            + From<TAuthorityError>
            + From<TPathError>
            + From<TQueryError>
            + From<TFragmentError>,
    {
        let uri_reference =
            URIReference::from_parts(Some(scheme), authority, path, query, fragment)
                .map_err(|error| URIError::try_from(error).unwrap())?;
        Ok(URI { uri_reference })
    }

    /// Returns the fragment, if present, of the URI.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://example.com#fragment").unwrap();

    /// assert_eq!(uri.fragment().unwrap(), "fragment");

    /// ```

    pub fn fragment(&self) -> Option<&Fragment<'uri>> {
        self.uri_reference.fragment()
    }

    /// Returns whether the URI has an authority component.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://example.com").unwrap();

    /// assert!(uri.has_authority());

    ///

    /// let uri = URI::try_from("urn:test").unwrap();

    /// assert!(!uri.has_authority());

    /// ```

    pub fn has_authority(&self) -> bool {
        self.uri_reference.has_authority()
    }

    /// Returns whether the URI has a fragment component.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://example.com#test").unwrap();

    /// assert!(uri.has_fragment());

    ///

    /// let uri = URI::try_from("http://example.com").unwrap();

    /// assert!(!uri.has_fragment());

    /// ```

    pub fn has_fragment(&self) -> bool {
        self.uri_reference.has_fragment()
    }

    /// Returns whether the URI has a password component.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://user:pass@127.0.0.1").unwrap();

    /// assert!(uri.has_password());

    ///

    /// let uri = URI::try_from("http://user@127.0.0.1").unwrap();

    /// assert!(!uri.has_password());

    /// ```

    pub fn has_password(&self) -> bool {
        self.uri_reference.has_password()
    }

    /// Returns whether the URI has a port.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://127.0.0.1:8080").unwrap();

    /// assert!(uri.has_port());

    ///

    /// let uri = URI::try_from("http://127.0.0.1").unwrap();

    /// assert!(!uri.has_port());

    /// ```

    pub fn has_port(&self) -> bool {
        self.uri_reference.has_port()
    }

    /// Returns whether the URI has a query component.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://example.com/my/path?my=query").unwrap();

    /// assert!(uri.has_query());

    ///

    /// let uri = URI::try_from("http://example.com/my/path").unwrap();

    /// assert!(!uri.has_query());

    /// ```

    pub fn has_query(&self) -> bool {
        self.uri_reference.has_query()
    }

    /// Returns whether the URI has a username component.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://username@example.com").unwrap();

    /// assert!(uri.has_username());

    ///

    /// let uri = URI::try_from("http://example.com").unwrap();

    /// assert!(!uri.has_username());

    /// ```

    pub fn has_username(&self) -> bool {
        self.uri_reference.has_username()
    }

    /// Returns the host, if present, of the URI.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://username@example.com").unwrap();

    /// assert_eq!(uri.host().unwrap().to_string(), "example.com");

    /// ```

    pub fn host(&self) -> Option<&Host<'uri>> {
        self.uri_reference.host()
    }

    /// Converts the URI into a base URI (i.e. the fragment component is removed).

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://example.com#fragment").unwrap();

    /// assert_eq!(uri.to_string(), "http://example.com/#fragment");

    /// let uri = uri.into_base_uri();

    /// assert_eq!(uri.to_string(), "http://example.com/");

    /// ```

    pub fn into_base_uri(self) -> URI<'uri> {
        let (scheme, authority, path, query, _) = self.uri_reference.into_parts();
        let uri_reference =
            URIReference::from_parts(scheme, authority, path, query, None::<Fragment>).unwrap();
        URI { uri_reference }
    }

    /// Consumes the URI and converts it into a builder with the same values.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Fragment, Query, URI};

    ///

    /// let uri = URI::try_from("http://example.com/path?query#fragment").unwrap();

    /// let mut builder = uri.into_builder();

    /// builder.query(None::<Query>).fragment(None::<Fragment>);

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "http://example.com/path");

    /// ```

    pub fn into_builder(self) -> URIBuilder<'uri> {
        let (scheme, authority, path, query, fragment) = self.uri_reference.into_parts();
        let mut builder = URIBuilder::new();
        builder
            .scheme(scheme.unwrap())
            .authority(authority)
            .path(path)
            .query(query)
            .fragment(fragment);
        builder
    }

    /// Converts the [`URI`] into an owned copy.

    ///

    /// If you construct the URI from a source with a non-static lifetime, you may run into

    /// lifetime problems due to the way the struct is designed. Calling this function will ensure

    /// that the returned value has a static lifetime.

    ///

    /// This is different from just cloning. Cloning the URI will just copy the references, and thus

    /// the lifetime will remain the same.

    pub fn into_owned(self) -> URI<'static> {
        URI {
            uri_reference: self.uri_reference.into_owned(),
        }
    }

    /// Consumes the [`URI`] and returns its parts: scheme, authority, path, query, and fragment.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from(

    ///     "http://username:password@example.com:80/my/path?my=query#fragment",

    /// ).unwrap();

    /// let (scheme, authority, path, query, fragment) = uri.into_parts();

    ///

    /// assert_eq!(scheme, "http");

    /// assert_eq!(authority.unwrap().to_string(), "username:password@example.com:80");

    /// assert_eq!(path, "/my/path");

    /// assert_eq!(query.unwrap(), "my=query");

    /// assert_eq!(fragment.unwrap(), "fragment");

    /// ```

    pub fn into_parts(
        self,
    ) -> (
        Scheme<'uri>,
        Option<Authority<'uri>>,
        Path<'uri>,
        Option<Query<'uri>>,
        Option<Fragment<'uri>>,
    ) {
        let (scheme, authority, path, query, fragment) = self.uri_reference.into_parts();
        (scheme.unwrap(), authority, path, query, fragment)
    }

    /// Returns whether the URI is normalized.

    ///

    /// A normalized URI will have all of its components normalized.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://example.com/?a=b").unwrap();

    /// assert!(uri.is_normalized());

    ///

    /// let mut uri = URI::try_from("http://EXAMPLE.com/?a=b").unwrap();

    /// assert!(!uri.is_normalized());

    /// uri.normalize();

    /// assert!(uri.is_normalized());

    /// ```

    pub fn is_normalized(&self) -> bool {
        self.uri_reference.is_normalized()
    }

    /// Maps the authority using the given map function.

    ///

    /// This function will panic if, as a result of the authority change, the URI reference becomes

    /// invalid.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Authority, URI};

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.map_authority(|_| Some(Authority::try_from("127.0.0.1").unwrap()));

    /// assert_eq!(uri.to_string(), "http://127.0.0.1/");

    /// ```

    pub fn map_authority<TMapper>(&mut self, mapper: TMapper) -> Option<&Authority<'uri>>
    where
        TMapper: FnOnce(Option<Authority<'uri>>) -> Option<Authority<'uri>>,
    {
        self.uri_reference.map_authority(mapper)
    }

    /// Maps the fragment using the given map function.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Fragment, URI};

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.map_fragment(|_| Some(Fragment::try_from("fragment").unwrap()));

    /// assert_eq!(uri.to_string(), "http://example.com/#fragment");

    /// ```

    pub fn map_fragment<TMapper>(&mut self, mapper: TMapper) -> Option<&Fragment<'uri>>
    where
        TMapper: FnOnce(Option<Fragment<'uri>>) -> Option<Fragment<'uri>>,
    {
        self.uri_reference.map_fragment(mapper)
    }

    /// Maps the path using the given map function.

    ///

    /// This function will panic if, as a result of the path change, the URI becomes invalid.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.map_path(|mut path| {

    ///     path.push("test").unwrap();

    ///     path.push("path").unwrap();

    ///     path

    /// });

    /// assert_eq!(uri.to_string(), "http://example.com/test/path");

    /// ```

    pub fn map_path<TMapper>(&mut self, mapper: TMapper) -> &Path<'uri>
    where
        TMapper: FnOnce(Path<'uri>) -> Path<'uri>,
    {
        self.uri_reference.map_path(mapper)
    }

    /// Maps the query using the given map function.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Query, URI};

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.map_query(|_| Some(Query::try_from("query").unwrap()));

    /// assert_eq!(uri.to_string(), "http://example.com/?query");

    /// ```

    pub fn map_query<TMapper>(&mut self, mapper: TMapper) -> Option<&Query<'uri>>
    where
        TMapper: FnOnce(Option<Query<'uri>>) -> Option<Query<'uri>>,
    {
        self.uri_reference.map_query(mapper)
    }

    /// Maps the scheme using the given map function.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Scheme, URI};

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.map_scheme(|_| Scheme::try_from("https").unwrap());

    /// assert_eq!(uri.to_string(), "https://example.com/");

    /// ```

    pub fn map_scheme<TMapper>(&mut self, mapper: TMapper) -> Option<&Scheme<'uri>>
    where
        TMapper: FnOnce(Scheme<'uri>) -> Scheme<'uri>,
    {
        self.uri_reference
            .map_scheme(|scheme| Some(mapper(scheme.unwrap())))
    }

    /// Normalizes the URI.

    ///

    /// A normalized URI will have all of its components normalized.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let mut uri = URI::try_from("http://example.com/?a=b").unwrap();

    /// uri.normalize();

    /// assert_eq!(uri.to_string(), "http://example.com/?a=b");

    ///

    /// let mut uri = URI::try_from("http://EXAMPLE.com/?a=b").unwrap();

    /// assert_eq!(uri.to_string(), "http://EXAMPLE.com/?a=b");

    /// uri.normalize();

    /// assert_eq!(uri.to_string(), "http://example.com/?a=b");

    /// ```

    pub fn normalize(&mut self) {
        self.uri_reference.normalize();
    }

    /// Returns the path of the URI.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://127.0.0.1/my/path").unwrap();

    /// assert_eq!(uri.path(), "/my/path");

    /// ```

    pub fn path(&self) -> &Path<'uri> {
        self.uri_reference.path()
    }

    /// Returns the password, if present, of the URI.

    ///

    /// Usage of a password in URIs is deprecated.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://user:pass@example.com").unwrap();

    /// assert_eq!(uri.password().unwrap(), "pass");

    /// ```

    pub fn password(&self) -> Option<&Password<'uri>> {
        self.uri_reference.password()
    }

    /// Returns the port, if present, of the URI.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://example.com:8080/").unwrap();

    /// assert_eq!(uri.port().unwrap(), 8080);

    /// ```

    pub fn port(&self) -> Option<u16> {
        self.uri_reference.port()
    }

    /// Returns the query, if present, of the URI.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://127.0.0.1?my=query").unwrap();

    /// assert_eq!(uri.query().unwrap(), "my=query");

    /// ```

    pub fn query(&self) -> Option<&Query<'uri>> {
        self.uri_reference.query()
    }

    /// Creates a new URI which is created by resolving the given reference against this URI.

    ///

    /// The algorithm used for resolving the reference is described in

    /// [[RFC3986, Section 5.2.2](https://tools.ietf.org/html/rfc3986#section-5.2.2)].

    pub fn resolve(&self, reference: &'uri URIReference<'uri>) -> URI<'uri> {
        let mut builder = URIBuilder::new();

        if let Some(scheme) = reference.scheme() {
            let mut path = reference.path().clone();
            path.remove_dot_segments();

            builder
                .scheme(scheme.clone())
                .authority(reference.authority().cloned())
                .path(path)
                .query(reference.query().cloned());
        } else {
            if reference.authority().is_some() {
                let mut path = reference.path().clone();
                path.remove_dot_segments();

                builder
                    .authority(reference.authority().cloned())
                    .path(path)
                    .query(reference.query().cloned());
            } else {
                if reference.path().is_relative()
                    && reference.path().segments().len() == 1
                    && reference.path().segments()[0].is_empty()
                {
                    let mut path = self.path().clone();
                    path.remove_dot_segments();
                    builder.path(path);

                    if reference.query().is_some() {
                        builder.query(reference.query().cloned());
                    } else {
                        builder.query(self.query().cloned());
                    }
                } else {
                    if reference.path().is_absolute() {
                        let mut path = reference.path().clone();
                        path.remove_dot_segments();
                        builder.path(path);
                    } else {
                        let mut path = if self.authority().is_some()
                            && self.path().segments().len() == 1
                            && self.path().segments()[0].is_empty()
                        {
                            let mut path = reference.path().clone();
                            path.set_absolute(true);
                            path
                        } else {
                            let mut path = self.path().clone();
                            path.pop();

                            for segment in reference.path().segments() {
                                path.push(segment.clone()).unwrap();
                            }

                            path
                        };

                        path.remove_dot_segments();
                        builder.path(path);
                    }

                    builder.query(reference.query().cloned());
                }

                builder.authority(self.authority().cloned());
            }

            builder.scheme(self.scheme().clone());
        }

        builder.fragment(reference.fragment().cloned());
        builder.build().unwrap()
    }

    /// Returns the scheme of the URI.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://127.0.0.1/").unwrap();

    /// assert_eq!(uri.scheme(), "http");

    /// ```

    pub fn scheme(&self) -> &Scheme<'uri> {
        self.uri_reference.scheme().unwrap()
    }

    /// Sets the authority of the URI.

    ///

    /// An error will be returned if the conversion to an [`Authority`] fails.

    ///

    /// The existing path will be set to absolute (i.e. starts with a `'/'`).

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.set_authority(Some("user@example.com:80"));

    /// assert_eq!(uri.to_string(), "http://user@example.com:80/");

    /// ```

    pub fn set_authority<TAuthority, TAuthorityError>(
        &mut self,
        authority: Option<TAuthority>,
    ) -> Result<Option<&Authority<'uri>>, URIError>
    where
        Authority<'uri>: TryFrom<TAuthority, Error = TAuthorityError>,
        URIReferenceError: From<TAuthorityError>,
    {
        self.uri_reference
            .set_authority(authority)
            .map_err(|error| URIError::try_from(error).unwrap())
    }

    /// Sets the fragment of the URI.

    ///

    /// An error will be returned if the conversion to a [`Fragment`] fails.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.set_fragment(Some("fragment"));

    /// assert_eq!(uri.to_string(), "http://example.com/#fragment");

    /// ```

    pub fn set_fragment<TFragment, TFragmentError>(
        &mut self,
        fragment: Option<TFragment>,
    ) -> Result<Option<&Fragment<'uri>>, URIError>
    where
        Fragment<'uri>: TryFrom<TFragment, Error = TFragmentError>,
        URIReferenceError: From<TFragmentError>,
    {
        self.uri_reference
            .set_fragment(fragment)
            .map_err(|error| URIError::try_from(error).unwrap())
    }

    /// Sets the path of the URI.

    ///

    /// An error will be returned in one of two cases:

    ///  - The conversion to [`Path`] failed.

    ///  - The path was set to a value that resulted in an invalid URI.

    ///

    /// Regardless of whether the given path was set as absolute or relative, if the URI

    /// reference currently has an authority, the path will be forced to be absolute.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.set_path("my/path");

    /// assert_eq!(uri.to_string(), "http://example.com/my/path");

    /// ```

    pub fn set_path<TPath, TPathError>(&mut self, path: TPath) -> Result<&Path<'uri>, URIError>
    where
        Path<'uri>: TryFrom<TPath, Error = TPathError>,
        URIReferenceError: From<TPathError>,
    {
        self.uri_reference
            .set_path(path)
            .map_err(|error| URIError::try_from(error).unwrap())
    }

    /// Sets the query of the URI.

    ///

    /// An error will be returned if the conversion to a [`Query`] fails.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.set_query(Some("myquery"));

    /// assert_eq!(uri.to_string(), "http://example.com/?myquery");

    /// ```

    pub fn set_query<TQuery, TQueryError>(
        &mut self,
        query: Option<TQuery>,
    ) -> Result<Option<&Query<'uri>>, URIError>
    where
        Query<'uri>: TryFrom<TQuery, Error = TQueryError>,
        URIReferenceError: From<TQueryError>,
    {
        self.uri_reference
            .set_query(query)
            .map_err(|error| URIError::try_from(error).unwrap())
    }

    /// Sets the scheme of the URI.

    ///

    /// An error will be returned if the conversion to a [`Scheme`] fails.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let mut uri = URI::try_from("http://example.com").unwrap();

    /// uri.set_scheme("https");

    /// assert_eq!(uri.to_string(), "https://example.com/");

    /// ```

    pub fn set_scheme<TScheme, TSchemeError>(
        &mut self,
        scheme: TScheme,
    ) -> Result<&Scheme<'uri>, URIError>
    where
        Scheme<'uri>: TryFrom<TScheme, Error = TSchemeError>,
        URIReferenceError: From<TSchemeError>,
    {
        self.uri_reference
            .set_scheme(Some(scheme))
            .map_err(|error| URIError::try_from(error).unwrap())?;
        Ok(self.scheme())
    }

    /// Returns the username, if present, of the URI.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::URI;

    ///

    /// let uri = URI::try_from("http://username@example.com").unwrap();

    /// assert_eq!(uri.username().unwrap(), "username");

    /// ```

    pub fn username(&self) -> Option<&Username<'uri>> {
        self.uri_reference.username()
    }
}

impl Display for URI<'_> {
    fn fmt(&self, formatter: &mut Formatter) -> fmt::Result {
        self.uri_reference.fmt(formatter)
    }
}

impl<'uri> From<URI<'uri>> for String {
    fn from(value: URI<'uri>) -> Self {
        value.to_string()
    }
}

impl<'uri> From<URI<'uri>> for URIReference<'uri> {
    fn from(value: URI<'uri>) -> Self {
        value.uri_reference
    }
}

impl<'uri> TryFrom<&'uri [u8]> for URI<'uri> {
    type Error = URIError;

    fn try_from(value: &'uri [u8]) -> Result<Self, Self::Error> {
        let uri_reference =
            URIReference::try_from(value).map_err(|error| URIError::try_from(error).unwrap())?;

        if uri_reference.is_relative_reference() {
            Err(URIError::NotURI)
        } else {
            Ok(URI { uri_reference })
        }
    }
}

impl<'uri> TryFrom<&'uri str> for URI<'uri> {
    type Error = URIError;

    fn try_from(value: &'uri str) -> Result<Self, Self::Error> {
        URI::try_from(value.as_bytes())
    }
}

impl<'uri> TryFrom<URIReference<'uri>> for URI<'uri> {
    type Error = URIError;

    fn try_from(value: URIReference<'uri>) -> Result<Self, Self::Error> {
        if value.is_uri() {
            Ok(URI {
                uri_reference: value,
            })
        } else {
            Err(URIError::NotURI)
        }
    }
}

/// A builder type for [`URI]`.

///

/// You must use the [`URI::scheme`] and [`URI::path`] functions before building as URIs always

/// have a scheme and path. Everything else is optional.

#[derive(Clone, Debug, Default, Eq, PartialEq)]
pub struct URIBuilder<'uri> {
    /// All URIs are also URI references, so we just maintain a [`URIReferenceBuilder`] underneath.

    uri_reference_builder: URIReferenceBuilder<'uri>,
}

impl<'uri> URIBuilder<'uri> {
    /// Sets the authority part of the URI.

    ///

    /// It is optional to specify a authority.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Authority, Path, Scheme, URIBuilder};

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .scheme(Scheme::HTTP)

    ///     .authority(Some(Authority::try_from("example.com").unwrap()))

    ///     .path(Path::try_from("/my/path").unwrap());

    /// let reference = builder.build().unwrap();

    /// assert_eq!(reference.to_string(), "http://example.com/my/path");

    /// ```

    pub fn authority(&mut self, authority: Option<Authority<'uri>>) -> &mut Self {
        self.uri_reference_builder.authority(authority);
        self
    }

    /// Consumes the builder and tries to build a [`URI`].

    ///

    /// This function will error in one of three situations:

    ///  - A scheme and path were not specified in the builder.

    ///  - While all individual components were valid, their combination as a URI was invalid.

    ///

    /// # Examples

    ///

    /// First error type (scheme and/or path were not specified):

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Authority, Path, URIBuilder};

    ///

    /// let result = URIBuilder::new()

    ///     .with_authority(Some(Authority::try_from("example.com").unwrap()))

    ///     .with_path(Path::try_from("/my/path").unwrap())

    ///     .build();

    /// assert!(result.is_err());

    /// ```

    ///

    /// Second error type (URI with no authority cannot have path starting with `"//"`):

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Scheme, Path, URIBuilder};

    ///

    /// let result = URIBuilder::new()

    ///     .with_scheme(Scheme::URN)

    ///     .with_path(Path::try_from("//path").unwrap())

    ///     .build();

    /// assert!(result.is_err());

    /// ```

    pub fn build(self) -> Result<URI<'uri>, URIError> {
        let uri_reference = self
            .uri_reference_builder
            .build()
            .map_err(|error| URIError::try_from(error).unwrap())?;

        if !uri_reference.has_scheme() {
            return Err(URIError::MissingScheme);
        }

        Ok(URI { uri_reference })
    }

    /// Sets the fragment part of the URI.

    ///

    /// It is optional to specify a fragment.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Fragment, Path, Scheme, URIBuilder};

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .scheme(Scheme::URN)

    ///     .path(Path::try_from("path").unwrap())

    ///     .fragment(Some(Fragment::try_from("fragment").unwrap()));

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "urn:path#fragment");

    /// ```

    pub fn fragment(&mut self, fragment: Option<Fragment<'uri>>) -> &mut Self {
        self.uri_reference_builder.fragment(fragment);
        self
    }

    /// Constructs a new builder with nothing set.

    pub fn new() -> Self {
        URIBuilder::default()
    }

    /// Sets the path part of the URI.

    ///

    /// It is required to specify a path. Not doing so will result in an error during the

    /// [`URIBuilder::build`] function.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Path, Scheme, URIBuilder};

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .scheme(Scheme::URN)

    ///     .path(Path::try_from("path").unwrap());

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "urn:path");

    /// ```

    pub fn path(&mut self, path: Path<'uri>) -> &mut Self {
        self.uri_reference_builder.path(path);
        self
    }

    /// Sets the query part of the URI reference.

    ///

    /// It is optional to specify a query.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Path, Query, Scheme, URIBuilder};

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .scheme(Scheme::URN)

    ///     .path(Path::try_from("path").unwrap())

    ///     .query(Some(Query::try_from("query").unwrap()));

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "urn:path?query");

    /// ```

    pub fn query(&mut self, query: Option<Query<'uri>>) -> &mut Self {
        self.uri_reference_builder.query(query);
        self
    }

    /// Sets the scheme part of the URI reference.

    ///

    /// It is required to specify a scheme. Not doing so will result in an error during the

    /// [`URIBuilder::build`] function.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Authority, Path, Scheme, URIBuilder};

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .scheme(Scheme::HTTP)

    ///     .authority(Some(Authority::try_from("example.com").unwrap()))

    ///     .path(Path::try_from("/my/path").unwrap());

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "http://example.com/my/path");

    /// ```

    pub fn scheme(&mut self, scheme: Scheme<'uri>) -> &mut Self {
        self.uri_reference_builder.scheme(Some(scheme));
        self
    }

    /// Sets the authority part of the URI.1

    ///

    /// If the given authority is not a valid authority (i.e. the conversion fails), an error is

    /// stored internally and checked during the [`URIBuilder::build`] function. The error state

    /// will be rewritten for any following calls to this function.

    ///

    /// It is optional to specify an authority.

    ///

    /// # Examples

    ///

    /// ```

    /// use uriparse::URIBuilder;

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .try_scheme("http")

    ///     .unwrap()

    ///     .try_authority(Some("example.com"))

    ///     .unwrap()

    ///     .try_path("/my/path")

    ///     .unwrap();

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "http://example.com/my/path");

    /// ```

    pub fn try_authority<TAuthority, TAuthorityError>(
        &mut self,
        authority: Option<TAuthority>,
    ) -> Result<&mut Self, AuthorityError>
    where
        Authority<'uri>: TryFrom<TAuthority, Error = TAuthorityError>,
        AuthorityError: From<TAuthorityError>,
    {
        self.uri_reference_builder.try_authority(authority)?;
        Ok(self)
    }

    /// Sets the fragment part of the URI.

    ///

    /// If the given fragment is not a valid fragment (i.e. the conversion fails), an error is

    /// stored internally and checked during the [`URIBuilder::build`] function. The error state

    /// will be rewritten for any following calls to this function.

    ///

    /// It is optional to specify a fragment.

    ///

    /// # Examples

    ///

    /// ```

    /// use uriparse::URIBuilder;

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .try_scheme("urn")

    ///     .unwrap()

    ///     .try_path("path")

    ///     .unwrap()

    ///     .try_fragment(Some("fragment"))

    ///     .unwrap();

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "urn:path#fragment");

    /// ```

    pub fn try_fragment<TFragment, TFragmentError>(
        &mut self,
        fragment: Option<TFragment>,
    ) -> Result<&mut Self, FragmentError>
    where
        Fragment<'uri>: TryFrom<TFragment, Error = TFragmentError>,
        FragmentError: From<TFragmentError>,
    {
        self.uri_reference_builder.try_fragment(fragment)?;
        Ok(self)
    }

    /// Sets the path part of the URI.

    ///

    /// If the given path is not a valid path (i.e. the conversion fails), an error is stored

    /// internally and checked during the [`URIBuilder::build`] function. The error state will be

    /// rewritten for any following calls to this function.

    ///

    /// It is required to specify a path.

    ///

    /// # Examples

    ///

    /// ```

    /// use uriparse::URIBuilder;

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .try_scheme("urn")

    ///     .unwrap()

    ///     .try_path("path")

    ///     .unwrap();

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "urn:path");

    /// ```

    pub fn try_path<TPath, TPathError>(&mut self, path: TPath) -> Result<&mut Self, PathError>
    where
        Path<'uri>: TryFrom<TPath, Error = TPathError>,
        PathError: From<TPathError>,
    {
        self.uri_reference_builder.try_path(path)?;
        Ok(self)
    }

    /// Sets the query part of the URI.

    ///

    /// If the given query is not a valid query (i.e. the conversion fails), an error is stored

    /// internally and checked during the [`URIBuilder::build`] function. The error state will be

    /// rewritten for any following calls to this function.

    ///

    /// It is optional to specify a query.

    ///

    /// # Examples

    ///

    /// ```

    /// use uriparse::URIBuilder;

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .try_scheme("urn")

    ///     .unwrap()

    ///     .try_path("path")

    ///     .unwrap()

    ///     .try_query(Some("query"))

    ///     .unwrap();

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "urn:path?query");

    /// ```

    pub fn try_query<TQuery, TQueryError>(
        &mut self,
        query: Option<TQuery>,
    ) -> Result<&mut Self, QueryError>
    where
        Query<'uri>: TryFrom<TQuery, Error = TQueryError>,
        QueryError: From<TQueryError>,
    {
        self.uri_reference_builder.try_query(query)?;
        Ok(self)
    }

    /// Sets the scheme part of the URI.

    ///

    /// If the given scheme is not a valid scheme (i.e. the conversion fails), an error is stored

    /// internally and checked during the [`URIBuilder::build`] function. The error state will be

    /// rewritten for any following calls to this function.

    ///

    /// It is required to specify a scheme. Not doing so will result in an error during the

    /// [`URIBuilder::build`] function.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Path, Scheme, URIBuilder};

    ///

    /// let mut builder = URIBuilder::new();

    /// builder

    ///     .try_scheme("urn")

    ///     .unwrap()

    ///     .try_path("path")

    ///     .unwrap();

    /// let uri = builder.build().unwrap();

    /// assert_eq!(uri.to_string(), "urn:path");

    /// ```

    pub fn try_scheme<TScheme, TSchemeError>(
        &mut self,
        scheme: TScheme,
    ) -> Result<&mut Self, SchemeError>
    where
        Scheme<'uri>: TryFrom<TScheme, Error = TSchemeError>,
        SchemeError: From<TSchemeError>,
    {
        self.uri_reference_builder.try_scheme(Some(scheme))?;
        Ok(self)
    }

    /// Consumes the builder and sets the authority part of the URI.

    ///

    /// It is optional to specify an authority.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Authority, Path, Scheme, URIBuilder};

    ///

    /// let uri = URIBuilder::new()

    ///     .with_scheme(Scheme::HTTP)

    ///     .with_authority(Some(Authority::try_from("example.com").unwrap()))

    ///     .with_path(Path::try_from("/").unwrap())

    ///     .build()

    ///     .unwrap();

    /// assert_eq!(uri.to_string(), "http://example.com/")

    /// ```

    pub fn with_authority(mut self, authority: Option<Authority<'uri>>) -> Self {
        self.authority(authority);
        self
    }

    /// Consumes the builder and sets the fragment part of the URI.

    ///

    /// It is optional to specify a fragment.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Fragment, Path, Scheme, URIBuilder};

    ///

    /// let uri = URIBuilder::new()

    ///     .with_scheme(Scheme::URN)

    ///     .with_path(Path::try_from("").unwrap())

    ///     .with_fragment(Some(Fragment::try_from("fragment").unwrap()))

    ///     .build()

    ///     .unwrap();

    /// assert_eq!(uri.to_string(), "urn:#fragment")

    /// ```

    pub fn with_fragment(mut self, fragment: Option<Fragment<'uri>>) -> Self {
        self.fragment(fragment);
        self
    }

    /// Consumes the builder and sets the path part of the URI.

    ///

    /// It is required to specify a path. Not doing so will result in an error during the

    /// [`URIBuilder::build`] function.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Authority, Path, Scheme, URIBuilder};

    ///

    /// let reference = URIBuilder::new()

    ///     .with_scheme(Scheme::HTTP)

    ///     .with_authority(Some(Authority::try_from("example.com").unwrap()))

    ///     .with_path(Path::try_from("/").unwrap())

    ///     .build()

    ///     .unwrap();

    /// assert_eq!(reference.to_string(), "http://example.com/")

    /// ```

    pub fn with_path(mut self, path: Path<'uri>) -> Self {
        self.path(path);
        self
    }

    /// Consumes the builder and sets the query part of the URI.

    ///

    /// It is optional to specify a query.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Path, Query, Scheme, URIBuilder};

    ///

    /// let uri = URIBuilder::new()

    ///     .with_scheme(Scheme::URN)

    ///     .with_path(Path::try_from("").unwrap())

    ///     .with_query(Some(Query::try_from("query").unwrap()))

    ///     .build()

    ///     .unwrap();

    /// assert_eq!(uri.to_string(), "urn:?query")

    /// ```

    pub fn with_query(mut self, query: Option<Query<'uri>>) -> Self {
        self.query(query);
        self
    }

    /// Consumes the builder and sets the scheme part of the URI.

    ///

    /// It is required to specify a scheme. Not doing so will result in an error during the

    /// [`URIBuilder::build`] function.

    ///

    /// # Examples

    ///

    /// ```

    /// use std::convert::TryFrom;

    ///

    /// use uriparse::{Authority, Path, Scheme, URIBuilder};

    ///

    /// let reference = URIBuilder::new()

    ///     .with_scheme(Scheme::HTTP)

    ///     .with_authority(Some(Authority::try_from("example.com").unwrap()))

    ///     .with_path(Path::try_from("/").unwrap())

    ///     .build()

    ///     .unwrap();

    /// assert_eq!(reference.to_string(), "http://example.com/")

    /// ```

    pub fn with_scheme(mut self, scheme: Scheme<'uri>) -> Self {
        self.scheme(scheme);
        self
    }
}

/// An error representing an invalid URI.

#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
#[non_exhaustive]
pub enum URIError {
    /// Represents the case when there is no authority, but the first path segment starts with

    /// `"//"`. This is not allowed because it would be interpreted as an authority component.

    ///

    /// This can only occur when using creation functions that act on individual parts (e.g.

    /// [`URI::from_parts`]).

    AbsolutePathStartsWithTwoSlashes,

    /// The authority component of the relative reference was invalid.

    Authority(AuthorityError),

    /// The fragment component of the relative reference was invalid.

    Fragment(FragmentError),

    /// This error occurs when you do not specify a path component on the builder.

    ///

    /// This can only occur when using [`URIBuilder`].

    MissingPath,

    /// This error occurs when you do not specify a scheme component on the builder.

    ///

    /// This can only occur when using [`URIBuilder`].

    MissingScheme,

    /// When parsing from some byte string source, if the source ends up being a relative reference,

    /// then it is obviously not a URI.

    ///

    /// This can only occur when parsing from a byte string source.

    NotURI,

    /// The path component of the relative reference was invalid.

    Path(PathError),

    /// The query component of the relative reference was invalid.

    Query(QueryError),

    /// The scheme component of the relative reference was invalid.

    Scheme(SchemeError),
}

impl Display for URIError {
    fn fmt(&self, formatter: &mut Formatter) -> fmt::Result {
        use self::URIError::*;

        match self {
            AbsolutePathStartsWithTwoSlashes => {
                write!(formatter, "absolute path URI starts with two slashes")
            }
            Authority(error) => error.fmt(formatter),
            Fragment(error) => error.fmt(formatter),
            MissingPath => write!(formatter, "missing path"),
            MissingScheme => write!(formatter, "missing scheme"),
            NotURI => write!(formatter, "not URI"),
            Path(error) => error.fmt(formatter),
            Query(error) => error.fmt(formatter),
            Scheme(error) => error.fmt(formatter),
        }
    }
}

impl Error for URIError {}

impl From<Infallible> for URIError {
    fn from(_: Infallible) -> Self {
        URIError::AbsolutePathStartsWithTwoSlashes
    }
}

impl From<AuthorityError> for URIError {
    fn from(value: AuthorityError) -> Self {
        URIError::Authority(value)
    }
}

impl From<FragmentError> for URIError {
    fn from(value: FragmentError) -> Self {
        URIError::Fragment(value)
    }
}

impl From<PathError> for URIError {
    fn from(value: PathError) -> Self {
        URIError::Path(value)
    }
}

impl From<QueryError> for URIError {
    fn from(value: QueryError) -> Self {
        URIError::Query(value)
    }
}

impl From<SchemeError> for URIError {
    fn from(value: SchemeError) -> Self {
        URIError::Scheme(value)
    }
}

impl TryFrom<URIReferenceError> for URIError {
    type Error = ();

    fn try_from(value: URIReferenceError) -> Result<Self, Self::Error> {
        use self::URIError::*;

        match value {
            URIReferenceError::AbsolutePathStartsWithTwoSlashes => {
                Ok(AbsolutePathStartsWithTwoSlashes)
            }
            URIReferenceError::Authority(error) => Ok(Authority(error)),
            URIReferenceError::Fragment(error) => Ok(Fragment(error)),
            URIReferenceError::MissingPath => Ok(MissingPath),
            URIReferenceError::Path(error) => Ok(Path(error)),
            URIReferenceError::Query(error) => Ok(Query(error)),
            URIReferenceError::Scheme(error) => Ok(Scheme(error)),
            URIReferenceError::SchemelessPathStartsWithColonSegment => Err(()),
        }
    }
}

#[cfg(test)]
mod test {
    use super::*;

    #[test]
    fn test_resolve() {
        fn test_case(value: &str, expected: &str) {
            let base_uri = URI::try_from("http://a/b/c/d;p?q").unwrap();
            let reference = URIReference::try_from(value).unwrap();
            assert_eq!(base_uri.resolve(&reference).to_string(), expected);
        }

        test_case("g:h", "g:h");
        test_case("g", "http://a/b/c/g");
        test_case("./g", "http://a/b/c/g");
        test_case("g/", "http://a/b/c/g/");
        test_case("/g", "http://a/g");
        test_case("//g", "http://g/");
        test_case("?y", "http://a/b/c/d;p?y");
        test_case("g?y", "http://a/b/c/g?y");
        test_case("#s", "http://a/b/c/d;p?q#s");
        test_case("g#s", "http://a/b/c/g#s");
        test_case("g?y#s", "http://a/b/c/g?y#s");
        test_case(";x", "http://a/b/c/;x");
        test_case("g;x", "http://a/b/c/g;x");
        test_case("g;x?y#s", "http://a/b/c/g;x?y#s");
        test_case("", "http://a/b/c/d;p?q");
        test_case(".", "http://a/b/c/");
        test_case("./", "http://a/b/c/");
        test_case("..", "http://a/b/");
        test_case("../", "http://a/b/");
        test_case("../g", "http://a/b/g");
        test_case("../..", "http://a/");
        test_case("../../", "http://a/");
        test_case("../../g", "http://a/g");
        test_case("../../../g", "http://a/g");
        test_case("../../../g", "http://a/g");
        test_case("/./g", "http://a/g");
        test_case("/../g", "http://a/g");
        test_case("g.", "http://a/b/c/g.");
        test_case(".g", "http://a/b/c/.g");
        test_case("g..", "http://a/b/c/g..");
        test_case("..g", "http://a/b/c/..g");
        test_case("./../g", "http://a/b/g");
        test_case("./g/.", "http://a/b/c/g/");
        test_case("g/./h", "http://a/b/c/g/h");
        test_case("g/../h", "http://a/b/c/h");
        test_case("g;x=1/./y", "http://a/b/c/g;x=1/y");
        test_case("g;x=1/../y", "http://a/b/c/y");
        test_case("g?y/./x", "http://a/b/c/g?y/./x");
        test_case("g?y/../x", "http://a/b/c/g?y/../x");
        test_case("g#s/./x", "http://a/b/c/g#s/./x");
        test_case("g#s/../x", "http://a/b/c/g#s/../x");
        test_case("http:g", "http:g");
    }

    #[cfg(feature = "serde")]
    #[test]
    fn test_serde() {
        let uri = URI::try_from("http://a/b/c/d;p?q").unwrap();

        // Perform serialization

        let json_string = serde_json::to_string(&uri).unwrap();

        // Perform deserialization

        let uri2 = serde_json::from_str(&json_string).unwrap();

        assert_eq!(
            uri, uri2,
            "Information lost in serialization/deserialization"
        );
    }
}