//! Errors of the knowledge crate.

/// Everything that can go wrong chunking, indexing or searching.
#[derive(Debug, Clone, PartialEq, Eq, thiserror::Error)]
pub enum Error {
    /// The note is bigger than [`crate::caps::MAX_NOTE_BYTES`].
    #[error("note of {len} bytes exceeds the {max} byte limit")]
    NoteTooLarge {
        /// Note size, in bytes.
        len: usize,
        /// The limit, in bytes.
        max: usize,
    },
    /// Indexing the note would pass [`crate::caps::MAX_TOTAL_PASSAGES`].
    #[error("the index is full ({max} passages)")]
    IndexFull {
        /// The limit, in passages.
        max: usize,
    },
    /// A query has more terms than [`crate::caps::MAX_QUERY_TERMS`].
    #[error("query has {count} terms, the limit is {max}")]
    TooManyTerms {
        /// Terms given.
        count: usize,
        /// The limit.
        max: usize,
    },
    /// The path is empty or longer than [`crate::caps::MAX_PATH_BYTES`].
    #[error("invalid note path")]
    InvalidPath,
    /// The path is in an excluded or reserved folder.
    #[error("path is excluded from the knowledge index: {0}")]
    Excluded(String),
    /// A serialized vocabulary is malformed or over its size limit.
    #[error("invalid vocabulary cache: {0}")]
    InvalidCache(String),
    /// A byte range is outside the content or reversed.
    #[error("range {start}..{end} is outside content of {len} bytes")]
    InvalidRange {
        /// Range start, in bytes.
        start: usize,
        /// Range end, in bytes.
        end: usize,
        /// Content length, in bytes.
        len: usize,
    },
    /// A byte range starts or ends inside a `char`.
    #[error("range starts or ends inside a char")]
    NotCharBoundary,
}

/// Result type of the knowledge crate.
pub type Result<T> = std::result::Result<T, Error>;