use cid::Cid;
use std::io;
use thiserror::Error;

#[derive(Debug)]
pub enum VerificationKind {
    Node,
    Record { key: Vec<u8> },
}

#[derive(Error, Debug)]
pub enum StarError {
    #[error("IO error: {0}")]
    Io(#[from] io::Error),
    #[error("CBOR error: {0}")]
    Cbor(String),
    #[error("CID error: {0}")]
    Cid(#[from] cid::Error),
    #[error("Multihash error: {0}")]
    Multihash(#[from] cid::multihash::Error),
    #[error("Invalid STAR header")]
    InvalidHeader,
    #[error("Unexpected EOF")]
    UnexpectedEof,

    #[error("Verification failed for {kind:?}: expected {expected}, got {computed}")]
    VerificationFailed {
        kind: VerificationKind,
        expected: Box<Cid>,
        computed: Box<Cid>,
    },

    #[error("Invalid state: {0}")]
    InvalidState(String),

    #[error("Invalid structure: {0}")]
    InvalidStructure(String),

    #[error("Height mismatch: found {found}, expected {expected}")]
    HeightMismatch { found: u32, expected: u32 },

    #[error("Trailing data")]
    TrailingData,
}

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