syn-solidity 1.5.7

use crate::{Spanned, kw};
use proc_macro2::{Literal, Span};
use std::{fmt, str::FromStr};
use syn::{
    LitFloat, LitInt, Result,
    parse::{Lookahead1, Parse, ParseStream},
};

// TODO: Fixed point numbers

/// An integer or fixed-point number literal: `1` or `1.0`.
#[derive(Clone)]
pub enum LitNumber {
    Int(LitInt),
    Float(LitFloat),
}

impl fmt::Debug for LitNumber {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Self::Int(lit) => lit.fmt(f),
            Self::Float(lit) => lit.fmt(f),
        }
    }
}

impl Parse for LitNumber {
    fn parse(input: ParseStream<'_>) -> Result<Self> {
        let lookahead = input.lookahead1();
        if lookahead.peek(LitInt) {
            input.parse().map(Self::Int)
        } else if lookahead.peek(LitFloat) {
            input.parse().map(Self::Float)
        } else {
            Err(lookahead.error())
        }
    }
}

impl Spanned for LitNumber {
    fn span(&self) -> Span {
        match self {
            Self::Int(lit) => lit.span(),
            Self::Float(lit) => lit.span(),
        }
    }

    fn set_span(&mut self, span: Span) {
        match self {
            Self::Int(lit) => lit.set_span(span),
            Self::Float(lit) => lit.set_span(span),
        }
    }
}

impl LitNumber {
    pub fn new_int(repr: &str, span: Span) -> Self {
        Self::Int(LitInt::new(repr, span))
    }

    pub fn new_fixed(repr: &str, span: Span) -> Self {
        Self::Float(LitFloat::new(repr, span))
    }

    pub fn peek(lookahead: &Lookahead1<'_>) -> bool {
        lookahead.peek(LitInt) || lookahead.peek(LitFloat)
    }

    /// Returns the base-10 digits of the literal.
    pub fn base10_digits(&self) -> &str {
        match self {
            Self::Int(lit) => lit.base10_digits(),
            Self::Float(lit) => lit.base10_digits(),
        }
    }

    /// Parses the literal into a selected number type.
    ///
    /// This is equivalent to `lit.base10_digits().parse()` except that the
    /// resulting errors will be correctly spanned to point to the literal token
    /// in the macro input.
    pub fn base10_parse<N>(&self) -> Result<N>
    where
        N: FromStr,
        N::Err: fmt::Display,
    {
        match self {
            Self::Int(lit) => lit.base10_parse(),
            Self::Float(lit) => lit.base10_parse(),
        }
    }

    pub fn suffix(&self) -> &str {
        match self {
            Self::Int(lit) => lit.suffix(),
            Self::Float(lit) => lit.suffix(),
        }
    }

    pub fn token(&self) -> Literal {
        match self {
            Self::Int(lit) => lit.token(),
            Self::Float(lit) => lit.token(),
        }
    }
}

#[derive(Clone, Debug)]
pub struct LitDenominated {
    pub number: LitNumber,
    pub denom: SubDenomination,
}

impl Parse for LitDenominated {
    fn parse(input: ParseStream<'_>) -> Result<Self> {
        Ok(Self { number: input.parse()?, denom: input.parse()? })
    }
}

impl Spanned for LitDenominated {
    fn span(&self) -> Span {
        let span = self.number.span();
        span.join(self.denom.span()).unwrap_or(span)
    }

    fn set_span(&mut self, span: Span) {
        self.number.set_span(span);
        self.denom.set_span(span);
    }
}

kw_enum! {
    /// A sub-denomination suffix for a number literal.
    pub enum SubDenomination {
        Wei(kw::wei),
        Gwei(kw::gwei),
        Ether(kw::ether),

        Seconds(kw::seconds),
        Minutes(kw::minutes),
        Hours(kw::hours),
        Days(kw::days),
        Weeks(kw::weeks),
        Years(kw::years),
    }
}

impl SubDenomination {
    /// Returns the value of this sub-denomination.
    pub const fn value(self) -> u64 {
        // https://github.com/ethereum/solidity/blob/2a2a9d37ee69ca77ef530fe18524a3dc8b053104/libsolidity/ast/Types.cpp#L973
        match self {
            Self::Wei(..) => 1,
            Self::Gwei(..) => 1_000_000_000,
            Self::Ether(..) => 1_000_000_000_000_000_000,

            Self::Seconds(..) => 1,
            Self::Minutes(..) => 60,
            Self::Hours(..) => 3_600,
            Self::Days(..) => 86_400,
            Self::Weeks(..) => 604_800,
            Self::Years(..) => 31_536_000,
        }
    }
}