use crate::structures::CommandFun;
use proc_macro::TokenStream;
use proc_macro2::Span;
use proc_macro2::TokenStream as TokenStream2;
use quote::{format_ident, quote, ToTokens};
use syn::{
braced, bracketed, parenthesized,
parse::{Error, Parse, ParseStream, Result as SynResult},
parse_quote,
punctuated::Punctuated,
spanned::Spanned,
token::{Comma, Mut},
Ident, Lifetime, Lit, Type,
};
pub trait LitExt {
fn to_str(&self) -> String;
fn to_bool(&self) -> bool;
fn to_ident(&self) -> Ident;
}
impl LitExt for Lit {
fn to_str(&self) -> String {
match self {
Lit::Str(s) => s.value(),
Lit::ByteStr(s) => unsafe { String::from_utf8_unchecked(s.value()) },
Lit::Char(c) => c.value().to_string(),
Lit::Byte(b) => (b.value() as char).to_string(),
_ => panic!("values must be a (byte)string or a char"),
}
}
fn to_bool(&self) -> bool {
if let Lit::Bool(b) = self {
b.value
} else {
self.to_str()
.parse()
.unwrap_or_else(|_| panic!("expected bool from {:?}", self))
}
}
#[inline]
fn to_ident(&self) -> Ident {
Ident::new(&self.to_str(), self.span())
}
}
pub trait IdentExt2: Sized {
fn to_uppercase(&self) -> Self;
fn with_suffix(&self, suf: &str) -> Ident;
}
impl IdentExt2 for Ident {
#[inline]
fn to_uppercase(&self) -> Self {
format_ident!("{}", self.to_string().to_uppercase())
}
#[inline]
fn with_suffix(&self, suffix: &str) -> Ident {
format_ident!("{}_{}", self.to_string().to_uppercase(), suffix)
}
}
#[inline]
pub fn into_stream(e: Error) -> TokenStream {
e.to_compile_error().into()
}
macro_rules! propagate_err {
($res:expr) => {{
match $res {
Ok(v) => v,
Err(e) => return $crate::util::into_stream(e),
}
}};
}
#[derive(Debug)]
pub struct Bracketed<T>(pub Punctuated<T, Comma>);
impl<T: Parse> Parse for Bracketed<T> {
fn parse(input: ParseStream<'_>) -> SynResult<Self> {
let content;
bracketed!(content in input);
Ok(Bracketed(content.parse_terminated(T::parse)?))
}
}
#[derive(Debug)]
pub struct Braced<T>(pub Punctuated<T, Comma>);
impl<T: Parse> Parse for Braced<T> {
fn parse(input: ParseStream<'_>) -> SynResult<Self> {
let content;
braced!(content in input);
Ok(Braced(content.parse_terminated(T::parse)?))
}
}
#[derive(Debug)]
pub struct Parenthesised<T>(pub Punctuated<T, Comma>);
impl<T: Parse> Parse for Parenthesised<T> {
fn parse(input: ParseStream<'_>) -> SynResult<Self> {
let content;
parenthesized!(content in input);
Ok(Parenthesised(content.parse_terminated(T::parse)?))
}
}
#[derive(Debug)]
pub struct AsOption<T>(pub Option<T>);
impl<T> AsOption<T> {
#[inline]
pub fn map<U>(self, f: impl FnOnce(T) -> U) -> AsOption<U> {
AsOption(self.0.map(f))
}
}
impl<T: ToTokens> ToTokens for AsOption<T> {
fn to_tokens(&self, stream: &mut TokenStream2) {
match &self.0 {
Some(o) => stream.extend(quote!(Some(#o))),
None => stream.extend(quote!(None)),
}
}
}
impl<T> Default for AsOption<T> {
#[inline]
fn default() -> Self {
AsOption(None)
}
}
#[derive(Debug)]
pub struct Argument {
pub mutable: Option<Mut>,
pub name: Ident,
pub kind: Type,
}
impl ToTokens for Argument {
fn to_tokens(&self, stream: &mut TokenStream2) {
let Argument {
mutable,
name,
kind,
} = self;
stream.extend(quote! {
#mutable #name: #kind
});
}
}
#[inline]
pub fn generate_type_validation(have: Type, expect: Type) -> syn::Stmt {
parse_quote! {
serenity::static_assertions::assert_type_eq_all!(#have, #expect);
}
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum DeclarFor {
Command,
Help,
Check,
}
pub fn create_declaration_validations(fun: &mut CommandFun, dec_for: DeclarFor) -> SynResult<()> {
let len = match dec_for {
DeclarFor::Command => 3,
DeclarFor::Help => 6,
DeclarFor::Check => 4,
};
if fun.args.len() > len {
return Err(Error::new(
fun.args.last().unwrap().span(),
format_args!("function's arity exceeds more than {} arguments", len),
));
}
let context: Type = parse_quote!(&serenity::client::Context);
let message: Type = parse_quote!(&serenity::model::channel::Message);
let args: Type = parse_quote!(serenity::framework::standard::Args);
let args2: Type = parse_quote!(&mut serenity::framework::standard::Args);
let options: Type = parse_quote!(&serenity::framework::standard::CommandOptions);
let hoptions: Type = parse_quote!(&'static serenity::framework::standard::HelpOptions);
let groups: Type = parse_quote!(&[&'static serenity::framework::standard::CommandGroup]);
let owners: Type = parse_quote!(std::collections::HashSet<serenity::model::id::UserId>);
let mut index = 0;
let mut spoof_or_check = |kind: Type, name: &str| {
match fun.args.get(index) {
Some(x) => fun.body.insert(0, generate_type_validation(x.kind.clone(), kind)),
None => fun.args.push(Argument {
mutable: None,
name: Ident::new(name, Span::call_site()),
kind,
}),
}
index += 1;
};
spoof_or_check(context, "_ctx");
spoof_or_check(message, "_msg");
if dec_for == DeclarFor::Check {
spoof_or_check(args2, "_args");
spoof_or_check(options, "_options");
return Ok(());
}
spoof_or_check(args, "_args");
if dec_for == DeclarFor::Help {
spoof_or_check(hoptions, "_hoptions");
spoof_or_check(groups, "_groups");
spoof_or_check(owners, "_owners");
}
Ok(())
}
#[inline]
pub fn create_return_type_validation(r#fn: &mut CommandFun, expect: Type) {
let stmt = generate_type_validation(r#fn.ret.clone(), expect);
r#fn.body.insert(0, stmt);
}
#[inline]
pub fn populate_fut_lifetimes_on_refs(args: &mut Vec<Argument>) {
for arg in args {
if let Type::Reference(reference) = &mut arg.kind {
reference.lifetime = Some(Lifetime::new("'fut", Span::call_site()));
}
}
}