// SPDX-License-Identifier: MIT
use crate::impls::BaseCodec;
#[cfg(not(feature = "std"))]
use alloc::{string::String, vec::Vec};
/// Generates the `Base` enum and its implementation with encode/decode methods.
///
/// This macro creates a comprehensive base encoding enum with:
/// - Enum variants for each base type with documentation
/// - `from_code()` method to convert character codes to base types
/// - `code()` method to get the character code for a base
/// - `encode()` method to encode bytes to a base string
/// - `decode()` method to decode base strings back to bytes
///
/// # Macro Hygiene
///
/// This macro uses `$crate::` prefixes to ensure proper hygiene when invoked
/// from other modules or crates.
///
/// # Parameters
///
/// The macro accepts a comma-separated list of base definitions in the form:
/// ```text
/// #[doc = "Documentation"] 'code' => VariantName,
/// ```
///
/// Where:
/// - `#[doc = "..."]` - Documentation attribute for the enum variant
/// - `'code'` - The single character or emoji that identifies this base encoding
/// - `VariantName` - The `PascalCase` name for the enum variant
///
/// # Generated Code
///
/// For each base definition, the macro generates:
/// - An enum variant in the `Base` enum
/// - A match arm in `from_code()` that maps the character code to the variant
/// - A match arm in `code()` that returns the character code
/// - A match arm in `encode()` that delegates to the base's encode function
/// - A match arm in `decode()` that delegates to the base's decode function
///
/// # Example
///
/// ```ignore
/// build_base_enum! {
/// /// Base64 encoding
/// 'm' => Base64,
/// /// Base58 Bitcoin encoding
/// 'z' => Base58Btc,
/// }
/// ```
///
/// This generates a `Base` enum with `Base64` and `Base58Btc` variants,
/// and implements all required methods.
///
/// # Error Handling
///
/// The `from_code()` method returns `Result<Base>` and will return
/// `Error::UnknownBase` if given an unrecognized character code.
macro_rules! build_base_enum {
( $(#[$attr:meta] $code:expr => $base:ident,)* ) => {
/// List of types currently supported in the multibase spec.
///
/// Not all base types are supported by this library.
#[derive(PartialEq, Eq, Clone, Copy, Debug, Hash)]
pub enum Base {
$( #[$attr] $base, )*
}
impl Base {
/// Convert a character code to the matching base algorithm.
///
/// Returns `Error::UnknownBase` if the code doesn't match any supported base.
///
/// # Errors
///
/// Returns [`Error::UnknownBase`](crate::error::Error::UnknownBase) if `code`
/// does not correspond to any supported base encoding.
#[inline]
pub const fn from_code(code: char) -> $crate::error::Result<Self> {
match code {
$( $code => Ok(Self::$base), )*
_ => Err($crate::error::Error::UnknownBase { code }),
}
}
/// Get the character code corresponding to the base algorithm.
///
/// Each base encoding has a unique single-character (or emoji) prefix
/// that identifies it in multibase strings.
#[inline]
pub const fn code(&self) -> char {
match self {
$( Self::$base => $code, )*
}
}
/// Encode the given byte slice to a base string (without prefix).
///
/// This method returns only the encoded data, without the base code prefix.
/// Use the public `encode()` function to get the full multibase string.
#[inline]
pub fn encode<I: AsRef<[u8]>>(&self, input: I) -> String {
match self {
$( Self::$base => $crate::impls::$base::encode(input), )*
}
}
/// Decode the base string (without prefix) back to bytes.
///
/// The `strict` parameter controls whether to accept case-insensitive
/// input for applicable bases.
///
/// # Parameters
///
/// * `input` - The encoded string (without the multibase prefix)
/// * `strict` - If true, enforce strict decoding rules (case-sensitive, etc.)
///
/// # Errors
///
/// Returns an error if the input contains invalid characters for this base
/// or if the input is malformed.
#[inline]
pub fn decode<I: AsRef<str>>(&self, input: I, strict: bool) -> $crate::error::Result<Vec<u8>> {
match self {
$( Self::$base => $crate::impls::$base::decode(input, strict), )*
}
}
#[inline]
pub(crate) fn decode_into<I: AsRef<str>>(&self, input: I, strict: bool, buffer: &mut Vec<u8>) -> $crate::error::Result<()> {
match self {
$( Self::$base => $crate::impls::$base::decode_into(input, strict, buffer), )*
}
}
}
}
}
build_base_enum! {
/// 8-bit binary (encoder and decoder keeps data unmodified).
'\x00' => Identity,
/// Base2 (alphabet: 01).
'0' => Base2,
/// Base8 (alphabet: 01234567).
'7' => Base8,
/// Base10 (alphabet: 0123456789).
'9' => Base10,
/// Base16 lower hexadecimal (alphabet: 0123456789abcdef).
'f' => Base16Lower,
/// Base16 upper hexadecimal (alphabet: 0123456789ABCDEF).
'F' => Base16Upper,
/// Base32, rfc4648 no padding (alphabet: abcdefghijklmnopqrstuvwxyz234567).
'b' => Base32Lower,
/// Base32, rfc4648 no padding (alphabet: ABCDEFGHIJKLMNOPQRSTUVWXYZ234567).
'B' => Base32Upper,
/// Base32, rfc4648 with padding (alphabet: abcdefghijklmnopqrstuvwxyz234567).
'c' => Base32PadLower,
/// Base32, rfc4648 with padding (alphabet: ABCDEFGHIJKLMNOPQRSTUVWXYZ234567).
'C' => Base32PadUpper,
/// Base32hex, rfc4648 no padding (alphabet: 0123456789abcdefghijklmnopqrstuv).
'v' => Base32HexLower,
/// Base32hex, rfc4648 no padding (alphabet: 0123456789ABCDEFGHIJKLMNOPQRSTUV).
'V' => Base32HexUpper,
/// Base32hex, rfc4648 with padding (alphabet: 0123456789abcdefghijklmnopqrstuv).
't' => Base32HexPadLower,
/// Base32hex, rfc4648 with padding (alphabet: 0123456789ABCDEFGHIJKLMNOPQRSTUV).
'T' => Base32HexPadUpper,
/// z-base-32 (used by Tahoe-LAFS) (alphabet: ybndrfg8ejkmcpqxot1uwisza345h769).
'h' => Base32Z,
/// Base36, [0-9a-z] no padding (alphabet: 0123456789abcdefghijklmnopqrstuvwxyz).
'k' => Base36Lower,
/// Base36, [0-9A-Z] no padding (alphabet: 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ).
'K' => Base36Upper,
/// Base58 flicker (alphabet: 123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ).
'Z' => Base58Flickr,
/// Base58 bitcoin (alphabet: 123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz).
'z' => Base58Btc,
/// Base64, `rfc4648` no padding (alphabet: ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/).
'm' => Base64,
/// Base64, `rfc4648` with padding (alphabet: ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/).
'M' => Base64Pad,
/// Base64 url, `rfc4648` no padding (alphabet: ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_).
'u' => Base64Url,
/// Base64 url, `rfc4648` with padding (alphabet: ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_).
'U' => Base64UrlPad,
/// Base256Emoji (alphabet: 🚀🪐☄🛰🌌🌑🌒🌓🌔🌕🌖🌗🌘🌍🌏🌎🐉☀💻🖥💾💿😂❤😍🤣😊🙏💕😭😘👍😅👏😁🔥🥰💔💖💙😢🤔😆🙄💪😉☺👌🤗💜😔😎😇🌹🤦🎉💞✌✨🤷😱😌🌸🙌😋💗💚😏💛🙂💓🤩😄😀🖤😃💯🙈👇🎶😒🤭❣😜💋👀😪😑💥🙋😞😩😡🤪👊🥳😥🤤👉💃😳✋😚😝😴🌟😬🙃🍀🌷😻😓⭐✅🥺🌈😈🤘💦✔😣🏃💐☹🎊💘😠☝😕🌺🎂🌻😐🖕💝🙊😹🗣💫💀👑🎵🤞😛🔴😤🌼😫⚽🤙☕🏆🤫👈😮🙆🍻🍃🐶💁😲🌿🧡🎁⚡🌞🎈❌✊👋😰🤨😶🤝🚶💰🍓💢🤟🙁🚨💨🤬✈🎀🍺🤓😙💟🌱😖👶🥴▶➡❓💎💸⬇😨🌚🦋😷🕺⚠🙅😟😵👎🤲🤠🤧📌🔵💅🧐🐾🍒😗🤑🌊🤯🐷☎💧😯💆👆🎤🙇🍑❄🌴💣🐸💌📍🥀🤢👅💡💩👐📸👻🤐🤮🎼🥵🚩🍎🍊👼💍📣🥂)
'🚀' => Base256Emoji,
}