#![feature(proc_macro_quote)]
#![feature(proc_macro_totokens)]

extern crate proc_macro;

use std::borrow::Cow;
use std::ffi::{CStr, CString};

use proc_macro::*;

#[proc_macro]
pub fn run_tests(_: TokenStream) -> TokenStream {
    test_quote_impl();
    test_substitution();
    test_advanced();
    test_integer();
    test_floating();
    test_char();
    test_str();
    test_string();
    test_c_str();
    test_c_string();
    test_interpolated_literal();
    test_ident();
    test_underscore();
    test_duplicate();
    test_empty_quote();
    test_box_str();
    test_cow();
    test_append_tokens();
    test_outer_line_comment();
    test_inner_line_comment();
    test_outer_block_comment();
    test_inner_block_comment();
    test_outer_attr();
    test_inner_attr();
    test_quote_raw_id();

    TokenStream::new()
}

// Based on https://github.com/dtolnay/quote/blob/0245506323a3616daa2ee41c6ad0b871e4d78ae4/tests/test.rs
//
// FIXME(quote):
// The following tests are removed because they are not supported yet in `proc_macro::quote!`
//
// - quote_spanned:
//   - fn test_quote_spanned_impl
//   - fn test_type_inference_for_span
//   - wrong-type-span.rs
// - format_ident:
//   - fn test_format_ident
//   - fn test_format_ident_strip_raw
// - repetition:
//   - fn test_iter
//   - fn test_array
//   - fn test_fancy_repetition
//   - fn test_nested_fancy_repetition
//   - fn test_duplicate_name_repetition
//   - fn test_duplicate_name_repetition_no_copy
//   - fn test_btreeset_repetition
//   - fn test_variable_name_conflict
//   - fn test_nonrep_in_repetition
//   - fn test_closure
//   - fn test_star_after_repetition

struct X;

impl ToTokens for X {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        Ident::new("X", Span::call_site()).to_tokens(tokens)
    }
}

fn test_quote_impl() {
    let tokens = quote! {
        impl<'a, T: ToTokens> ToTokens for &'a T {
            fn to_tokens(&self, tokens: &mut TokenStream) {
                (**self).to_tokens(tokens)
            }
        }
    };

    let expected = r#"impl < 'a, T : ToTokens > ToTokens for & 'a T
{
    fn to_tokens(& self, tokens : & mut TokenStream)
    { (** self).to_tokens(tokens) }
}"#;

    assert_eq!(expected, tokens.to_string());
}

fn test_substitution() {
    let x = X;
    let tokens = quote!($x <$x> ($x) [$x] {$x});

    let expected = "X <X > (X) [X] { X }";

    assert_eq!(expected, tokens.to_string());
}

fn test_advanced() {
    let generics = quote!( <'a, T> );

    let where_clause = quote!( where T: Serialize );

    let field_ty = quote!(String);

    let item_ty = quote!(Cow<'a, str>);

    let path = quote!(SomeTrait::serialize_with);

    let value = quote!(self.x);

    let tokens = quote! {
        struct SerializeWith $generics $where_clause {
            value: &'a $field_ty,
            phantom: ::std::marker::PhantomData<$item_ty>,
        }

        impl $generics ::serde::Serialize for SerializeWith $generics $where_clause {
            fn serialize<S>(&self, s: &mut S) -> Result<(), S::Error>
                where S: ::serde::Serializer
            {
                $path(self.value, s)
            }
        }

        SerializeWith {
            value: $value,
            phantom: ::std::marker::PhantomData::<$item_ty>,
        }
    };

    let expected = r#"struct SerializeWith < 'a, T > where T : Serialize
{
    value : & 'a String, phantom : :: std :: marker :: PhantomData <Cow < 'a,
    str > >,
} impl < 'a, T > :: serde :: Serialize for SerializeWith < 'a, T > where T :
Serialize
{
    fn serialize < S > (& self, s : & mut S) -> Result < (), S :: Error >
    where S : :: serde :: Serializer
    { SomeTrait :: serialize_with(self.value, s) }
} SerializeWith
{
    value : self.x, phantom : :: std :: marker :: PhantomData ::<Cow < 'a, str
    > >,
}"#;

    assert_eq!(expected, tokens.to_string());
}

fn test_integer() {
    let ii8 = -1i8;
    let ii16 = -1i16;
    let ii32 = -1i32;
    let ii64 = -1i64;
    let ii128 = -1i128;
    let iisize = -1isize;
    let uu8 = 1u8;
    let uu16 = 1u16;
    let uu32 = 1u32;
    let uu64 = 1u64;
    let uu128 = 1u128;
    let uusize = 1usize;

    let tokens = quote! {
        1 1i32 1u256
        $ii8 $ii16 $ii32 $ii64 $ii128 $iisize
        $uu8 $uu16 $uu32 $uu64 $uu128 $uusize
    };
    let expected = r#"1 1i32 1u256 -1i8 -1i16 -1i32 -1i64 -1i128 -1isize 1u8 1u16 1u32 1u64 1u128
1usize"#;
    assert_eq!(expected, tokens.to_string());
}

fn test_floating() {
    let e32 = 2.345f32;

    let e64 = 2.345f64;

    let tokens = quote! {
        $e32
        $e64
    };
    let expected = concat!("2.345f32 2.345f64");
    assert_eq!(expected, tokens.to_string());
}

fn test_char() {
    let zero = '\u{1}';
    let dollar = '$';
    let pound = '#';
    let quote = '"';
    let apost = '\'';
    let newline = '\n';
    let heart = '\u{2764}';

    let tokens = quote! {
        $zero $dollar $pound $quote $apost $newline $heart
    };
    let expected = "'\\u{1}' '$' '#' '\"' '\\'' '\\n' '\u{2764}'";
    assert_eq!(expected, tokens.to_string());
}

fn test_str() {
    let s = "\u{1} a 'b \" c";
    let tokens = quote!($s);
    let expected = "\"\\u{1} a 'b \\\" c\"";
    assert_eq!(expected, tokens.to_string());
}

fn test_string() {
    let s = "\u{1} a 'b \" c".to_string();
    let tokens = quote!($s);
    let expected = "\"\\u{1} a 'b \\\" c\"";
    assert_eq!(expected, tokens.to_string());
}

fn test_c_str() {
    let s = CStr::from_bytes_with_nul(b"\x01 a 'b \" c\0").unwrap();
    let tokens = quote!($s);
    let expected = "c\"\\u{1} a 'b \\\" c\"";
    assert_eq!(expected, tokens.to_string());
}

fn test_c_string() {
    let s = CString::new(&b"\x01 a 'b \" c"[..]).unwrap();
    let tokens = quote!($s);
    let expected = "c\"\\u{1} a 'b \\\" c\"";
    assert_eq!(expected, tokens.to_string());
}

fn test_interpolated_literal() {
    macro_rules! m {
        ($literal:literal) => {
            quote!($literal)
        };
    }

    let tokens = m!(1);
    let expected = "1";
    assert_eq!(expected, tokens.to_string());

    let tokens = m!(-1);
    let expected = "- 1";
    assert_eq!(expected, tokens.to_string());

    let tokens = m!(true);
    let expected = "true";
    assert_eq!(expected, tokens.to_string());

    let tokens = m!(-true);
    let expected = "- true";
    assert_eq!(expected, tokens.to_string());
}

fn test_ident() {
    let foo = Ident::new("Foo", Span::call_site());
    let bar = Ident::new(&format!("Bar{}", 7), Span::call_site());
    let tokens = quote!(struct $foo; enum $bar {});
    let expected = "struct Foo; enum Bar7 {}";
    assert_eq!(expected, tokens.to_string());
}

fn test_underscore() {
    let tokens = quote!(let _;);
    let expected = "let _;";
    assert_eq!(expected, tokens.to_string());
}

fn test_duplicate() {
    let ch = 'x';

    let tokens = quote!($ch $ch);

    let expected = "'x' 'x'";
    assert_eq!(expected, tokens.to_string());
}

fn test_empty_quote() {
    let tokens = quote!();
    assert_eq!("", tokens.to_string());
}

fn test_box_str() {
    let b = "str".to_owned().into_boxed_str();
    let tokens = quote! { $b };
    assert_eq!("\"str\"", tokens.to_string());
}

fn test_cow() {
    let owned: Cow<Ident> = Cow::Owned(Ident::new("owned", Span::call_site()));

    let ident = Ident::new("borrowed", Span::call_site());
    let borrowed = Cow::Borrowed(&ident);

    let tokens = quote! { $owned $borrowed };
    assert_eq!("owned borrowed", tokens.to_string());
}

fn test_append_tokens() {
    let mut a = quote!(a);
    let b = quote!(b);
    a.extend(b);
    assert_eq!("a b", a.to_string());
}

fn test_outer_line_comment() {
    let tokens = quote! {
        /// doc
    };
    let expected = "#[doc = \" doc\"]";
    assert_eq!(expected, tokens.to_string());
}

fn test_inner_line_comment() {
    let tokens = quote! {
        //! doc
    };
    let expected = "# ! [doc = \" doc\"]";
    assert_eq!(expected, tokens.to_string());
}

fn test_outer_block_comment() {
    let tokens = quote! {
        /** doc */
    };
    let expected = "#[doc = \" doc \"]";
    assert_eq!(expected, tokens.to_string());
}

fn test_inner_block_comment() {
    let tokens = quote! {
        /*! doc */
    };
    let expected = "# ! [doc = \" doc \"]";
    assert_eq!(expected, tokens.to_string());
}

fn test_outer_attr() {
    let tokens = quote! {
        #[inline]
    };
    let expected = "#[inline]";
    assert_eq!(expected, tokens.to_string());
}

fn test_inner_attr() {
    let tokens = quote! {
        #![no_std]
    };
    let expected = "#! [no_std]";
    assert_eq!(expected, tokens.to_string());
}

fn test_quote_raw_id() {
    let id = quote!(r#raw_id);
    assert_eq!(id.to_string(), "r#raw_id");
}