use std::fmt::Display;

use thiserror::Error;

use crate::serde::T;

pub type Result<T> = std::result::Result<T, Error>;

// This is a bare-bones implementation. A real library would provide additional
// information in its error type, for example the line and column at which the
// error occurred, the byte offset into the input, or the current key being
// processed.
#[derive(Debug, Error)]
pub enum Error {
    #[error("{0}")]
    Message(String),
    #[error(transparent)]
    Io(#[from] std::io::Error),
    #[error("expected {expected:?}, found {found}")]
    Expected { expected: T, found: u8 },
    #[error(transparent)]
    FromUtf8Error(#[from] std::string::FromUtf8Error),
    #[error(transparent)]
    Utf8Error(#[from] std::str::Utf8Error),
    #[error("a length is required for most things")]
    LenLess,
    #[error("char {0} was not in the valid range of chars")]
    NotChar(u32),
    #[error("out of bounds index")]
    OOB,
    #[error("{0} is not a tag")]
    NotTag(u8),
    #[error("out of range")]
    Overflow,
    #[error(
        "the length provided in the data stream {0} is different from the hint serde provided {1}"
    )]
    IncoherentLen(usize, usize),
    #[error(transparent)]
    TryFromIntError(#[from] std::num::TryFromIntError),
}

impl serde::ser::Error for Error {
    fn custom<T>(msg: T) -> Self
    where
        T: Display,
    {
        Self::Message(msg.to_string())
    }
}
impl serde::de::Error for Error {
    fn custom<T>(msg: T) -> Self
    where
        T: Display,
    {
        Self::Message(msg.to_string())
    }
}