use std::fmt;

pub enum Class {
    Informational,
    Success,
    Redirection,
    ClientError,
    ServerError,
    Unknown
}

#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq)]
pub struct Status {
    /// The HTTP status code associated with this status.
    pub code: u16,
    /// The HTTP reason phrase associated with this status.
    pub reason: &'static str
}

macro_rules! ctrs {
    ($($code:expr, $code_str:expr, $name:ident => $reason:expr),+) => {
        pub fn from_code(code: u16) -> Option<Status> {
            match code {
                $($code => Some(Status::$name),)+
                _ => None
            }
        }

        $(
            #[doc="[Status](struct.Status.html) with code <b>"]
            #[doc=$code_str]
            #[doc="</b> and reason <i>"]
            #[doc=$reason]
            #[doc="</i>."]
            #[allow(non_upper_case_globals)]
            pub const $name: Status = Status::new($code, $reason);
         )+
    };
}

impl Status {
    #[inline(always)]
    pub const fn new(code: u16, reason: &'static str) -> Status {
        Status {
            code: code,
            reason: reason
        }
    }

    pub fn class(&self) -> Class {
        match self.code / 100 {
            1 => Class::Informational,
            2 => Class::Success,
            3 => Class::Redirection,
            4 => Class::ClientError,
            5 => Class::ServerError,
            _ => Class::Unknown
        }
    }

    ctrs! {
        100, "100", Continue => "Continue",
        101, "101", SwitchingProtocols => "Switching Protocols",
        102, "102", Processing => "Processing",
        200, "200", Ok => "OK",
        201, "201", Created => "Created",
        202, "202", Accepted => "Accepted",
        203, "203", NonAuthoritativeInformation => "Non-Authoritative Information",
        204, "204", NoContent => "No Content",
        205, "205", ResetContent => "Reset Content",
        206, "206", PartialContent => "Partial Content",
        207, "207", MultiStatus => "Multi-Status",
        208, "208", AlreadyReported => "Already Reported",
        226, "226", ImUsed => "IM Used",
        300, "300", MultipleChoices => "Multiple Choices",
        301, "301", MovedPermanently => "Moved Permanently",
        302, "302", Found => "Found",
        303, "303", SeeOther => "See Other",
        304, "304", NotModified => "Not Modified",
        305, "305", UseProxy => "Use Proxy",
        307, "307", TemporaryRedirect => "Temporary Redirect",
        308, "308", PermanentRedirect => "Permanent Redirect",
        400, "400", BadRequest => "Bad Request",
        401, "401", Unauthorized => "Unauthorized",
        402, "402", PaymentRequired => "Payment Required",
        403, "403", Forbidden => "Forbidden",
        404, "404", NotFound => "Not Found",
        405, "405", MethodNotAllowed => "Method Not Allowed",
        406, "406", NotAcceptable => "Not Acceptable",
        407, "407", ProxyAuthenticationRequired => "Proxy Authentication Required",
        408, "408", RequestTimeout => "Request Timeout",
        409, "409", Conflict => "Conflict",
        410, "410", Gone => "Gone",
        411, "411", LengthRequired => "Length Required",
        412, "412", PreconditionFailed => "Precondition Failed",
        413, "413", PayloadTooLarge => "Payload Too Large",
        414, "414", UriTooLong => "URI Too Long",
        415, "415", UnsupportedMediaType => "Unsupported Media Type",
        416, "416", RangeNotSatisfiable => "Range Not Satisfiable",
        417, "417", ExpectationFailed => "Expectation Failed",
        418, "418", ImATeapot => "I'm a teapot",
        421, "421", MisdirectedRequest => "Misdirected Request",
        422, "422", UnprocessableEntity => "Unprocessable Entity",
        423, "423", Locked => "Locked",
        424, "424", FailedDependency => "Failed Dependency",
        426, "426", UpgradeRequired => "Upgrade Required",
        428, "428", PreconditionRequired => "Precondition Required",
        429, "429", TooManyRequests => "Too Many Requests",
        431, "431", RequestHeaderFieldsTooLarge => "Request Header Fields Too Large",
        451, "451", UnavailableForLegalReasons => "Unavailable For Legal Reasons",
        500, "500", InternalServerError => "Internal Server Error",
        501, "501", NotImplemented => "Not Implemented",
        502, "502", BadGateway => "Bad Gateway",
        503, "503", ServiceUnavailable => "Service Unavailable",
        504, "504", GatewayTimeout => "Gateway Timeout",
        505, "505", HttpVersionNotSupported => "HTTP Version Not Supported",
        506, "506", VariantAlsoNegotiates => "Variant Also Negotiates",
        507, "507", InsufficientStorage => "Insufficient Storage",
        508, "508", LoopDetected => "Loop Detected",
        510, "510", NotExtended => "Not Extended",
        511, "511", NetworkAuthenticationRequired => "Network Authentication Required"
    }

    #[doc(hidden)]
    #[inline]
    pub fn raw(code: u16) -> Status {
        match Status::from_code(code) {
            Some(status) => status,
            None => Status::new(code, "<unknown code>")
        }
    }
}

impl fmt::Display for Status {
    #[inline(always)]
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{} {}", self.code, self.reason)
    }
}