//! Library error structures and enums

use tokio_rustls::rustls;

#[cfg(feature = "hickory")]
use hickory_client::{
    error::ClientError as HickoryClientError, proto::error::ProtoError as HickoryProtoError,
};

/// Main error structure, also a wrapper for everything else
#[derive(Debug)]
pub enum LibError {
    /// General I/O error
    // TODO: separate somehow
    IoError(std::io::Error),
    /// URL parse or check error
    InvalidUrlError(InvalidUrl),
    /// DNS server has provided no suitable records
    /// (e. g. domain does not exist)
    HostLookupError,
    /// TLS library error related to certificate/signature
    /// verification failure or connection failure
    RustlsError(rustls::Error),
    /// Response status code is out of [10; 69] range
    StatusOutOfRange(u8),
    /// Response metadata or content cannot be parsed
    /// as a UTF-8 string without errors
    DataNotUtf8(std::string::FromUtf8Error),
    /// Provided string is not a valid MIME type
    InvalidMime(mime::FromStrError),
    /// Hickory DNS client error
    #[cfg(feature = "hickory")]
    DnsClientError(HickoryClientError),
}

impl From<std::io::Error> for LibError {
    #[inline]
    fn from(err: std::io::Error) -> Self {
        Self::IoError(err)
    }
}

impl From<url::ParseError> for LibError {
    #[inline]
    fn from(err: url::ParseError) -> Self {
        Self::InvalidUrlError(InvalidUrl::ParseError(err))
    }
}

impl From<InvalidUrl> for LibError {
    #[inline]
    fn from(err: InvalidUrl) -> Self {
        Self::InvalidUrlError(err)
    }
}

impl From<rustls::Error> for LibError {
    #[inline]
    fn from(err: rustls::Error) -> Self {
        Self::RustlsError(err)
    }
}

impl From<rustls::CertificateError> for LibError {
    #[inline]
    fn from(err: rustls::CertificateError) -> Self {
        Self::RustlsError(err.into())
    }
}

impl LibError {
    #[inline]
    pub fn status_out_of_range(num: u8) -> Self {
        Self::StatusOutOfRange(num)
    }
}

impl From<std::string::FromUtf8Error> for LibError {
    #[inline]
    fn from(err: std::string::FromUtf8Error) -> Self {
        Self::DataNotUtf8(err)
    }
}

impl From<mime::FromStrError> for LibError {
    #[inline]
    fn from(err: mime::FromStrError) -> Self {
        Self::InvalidMime(err)
    }
}

#[cfg(feature = "hickory")]
impl From<HickoryClientError> for LibError {
    #[inline]
    fn from(err: HickoryClientError) -> Self {
        Self::DnsClientError(err)
    }
}

#[cfg(feature = "hickory")]
impl From<HickoryProtoError> for LibError {
    #[inline]
    fn from(err: HickoryProtoError) -> Self {
        Self::DnsClientError(err.into())
    }
}

/// URL parse or check error
#[derive(Debug)]
pub enum InvalidUrl {
    /// Provided string cannot be parsed as a valid URL with [`url::Url`]
    ParseError(url::ParseError),
    /// URL scheme is not `gemini://`
    SchemeNotGemini,
    /// URL contains userinfo -- `user:pswd@` --
    /// which is forbidden by Gemini spec
    UserinfoPresent,
    /// Could not extract host from the URL or convert host and port into
    /// [`std::net::SocketAddr`] or [`crate::certs::ServerName`]
    ConvertError,
}