// Copyright 2014-2017 The html5ever Project Developers. See the
// COPYRIGHT file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

use html5ever::driver::ParseOpts;
use html5ever::serialize::{Serialize, SerializeOpts, Serializer, TraversalScope};
use html5ever::tendril::{SliceExt, StrTendril, TendrilSink};
use html5ever::tokenizer::{TagKind, Token, TokenSink, TokenSinkResult, Tokenizer};
use html5ever::{parse_document, parse_fragment, serialize, QualName};
use markup5ever::{local_name, namespace_url, ns};
use markup5ever_rcdom::{RcDom, SerializableHandle};

use std::cell::RefCell;
use std::io;

struct Tokens(RefCell<Vec<Token>>);

impl TokenSink for Tokens {
    type Handle = ();

    fn process_token(&self, token: Token, _: u64) -> TokenSinkResult<()> {
        self.0.borrow_mut().push(token);
        TokenSinkResult::Continue
    }
}

impl Serialize for Tokens {
    fn serialize<S>(&self, serializer: &mut S, _: TraversalScope) -> io::Result<()>
    where
        S: Serializer,
    {
        for t in self.0.borrow().iter() {
            match &t {
                // TODO: check whether this is an IE conditional comment or a spec comment
                Token::TagToken(tag) => {
                    let name = QualName::new(
                        None,
                        "http://www.w3.org/1999/xhtml".into(),
                        tag.name.as_ref().into(),
                    );
                    match tag.kind {
                        TagKind::StartTag => serializer.start_elem(
                            name,
                            tag.attrs.iter().map(|at| (&at.name, &at.value[..])),
                        )?,
                        TagKind::EndTag => serializer.end_elem(name)?,
                    }
                },
                Token::DoctypeToken(dt) => {
                    if let Some(name) = &dt.name {
                        serializer.write_doctype(name)?
                    }
                },
                Token::CommentToken(chars) => serializer.write_comment(chars)?,
                Token::CharacterTokens(chars) => serializer.write_text(chars)?,
                Token::NullCharacterToken | &Token::EOFToken => {},
                Token::ParseError(e) => println!("parse error: {e:#?}"),
            }
        }
        Ok(())
    }
}

fn tokenize_and_serialize(input: StrTendril) -> StrTendril {
    let input = {
        let q = ::html5ever::tokenizer::BufferQueue::default();
        q.push_front(input);
        q
    };
    let tokenizer = Tokenizer::new(Tokens(RefCell::new(vec![])), Default::default());
    let _ = tokenizer.feed(&input);
    tokenizer.end();
    let mut output = ::std::io::Cursor::new(vec![]);
    serialize(
        &mut output,
        &tokenizer.sink,
        SerializeOpts {
            create_missing_parent: true,
            ..Default::default()
        },
    )
    .unwrap();
    StrTendril::try_from_byte_slice(&output.into_inner()).unwrap()
}

fn parse_and_serialize(input: StrTendril) -> StrTendril {
    let dom = parse_fragment(
        RcDom::default(),
        ParseOpts::default(),
        QualName::new(None, ns!(html), local_name!("body")),
        vec![],
    )
    .one(input);
    let inner: SerializableHandle = dom.document.children.borrow()[0].clone().into();

    let mut result = vec![];
    serialize(&mut result, &inner, Default::default()).unwrap();
    StrTendril::try_from_byte_slice(&result).unwrap()
}

macro_rules! test_fn {
    ($f:ident, $name:ident, $input:expr, $output:expr) => {
        #[test]
        fn $name() {
            assert_eq!($output, &*$f($input.to_tendril()));
        }
    };

    // Shorthand for $output = $input
    ($f:ident, $name:ident, $input:expr) => {
        test_fn!($f, $name, $input, $input);
    };
}

macro_rules! test {
    ($($t:tt)*) => {
        test_fn!(parse_and_serialize, $($t)*);
    };
}

macro_rules! test_no_parse {
    ($($t:tt)*) => {
        test_fn!(tokenize_and_serialize, $($t)*);
    };
}

test!(empty, r#""#);
test!(fuzz, "<a a=\r\n", "");
test!(smoke_test, r#"<p><i>Hello</i>, World!</p>"#);

test!(
    misnest,
    r#"<p><i>Hello!</p>, World!</i>"#,
    r#"<p><i>Hello!</i></p><i>, World!</i>"#
);

test!(attr_literal, r#"<base foo="<'>">"#);
test!(attr_escape_amp, r#"<base foo="&amp;">"#);
test!(
    attr_escape_amp_2,
    r#"<base foo=&amp>"#,
    r#"<base foo="&amp;">"#
);
test!(
    attr_escape_nbsp,
    "<base foo=x\u{a0}y>",
    r#"<base foo="x&nbsp;y">"#
);
test!(
    attr_escape_quot,
    r#"<base foo='"'>"#,
    r#"<base foo="&quot;">"#
);
test!(
    attr_escape_several,
    r#"<span foo=3 title='test "with" &amp;quot;'>"#,
    r#"<span foo="3" title="test &quot;with&quot; &amp;quot;"></span>"#
);

test!(text_literal, r#"<p>"'"</p>"#);
test!(text_escape_amp, r#"<p>&amp;</p>"#);
test!(text_escape_amp_2, r#"<p>&amp</p>"#, r#"<p>&amp;</p>"#);
test!(text_escape_nbsp, "<p>x\u{a0}y</p>", r#"<p>x&nbsp;y</p>"#);
test!(text_escape_lt, r#"<p>&lt;</p>"#);
test!(text_escape_gt, r#"<p>&gt;</p>"#);
test!(text_escape_gt2, r#"<p>></p>"#, r#"<p>&gt;</p>"#);

test!(
    script_literal,
    r#"<script>(x & 1) < 2; y > "foo" + 'bar'</script>"#
);
test!(
    style_literal,
    r#"<style>(x & 1) < 2; y > "foo" + 'bar'</style>"#
);
test!(xmp_literal, r#"<xmp>(x & 1) < 2; y > "foo" + 'bar'</xmp>"#);
test!(
    iframe_literal,
    r#"<iframe>(x & 1) < 2; y > "foo" + 'bar'</iframe>"#
);
test!(
    noembed_literal,
    r#"<noembed>(x & 1) < 2; y > "foo" + 'bar'</noembed>"#
);
test!(
    noframes_literal,
    r#"<noframes>(x & 1) < 2; y > "foo" + 'bar'</noframes>"#
);

test!(pre_lf_0, "<pre>foo bar</pre>");
test!(pre_lf_1, "<pre>\nfoo bar</pre>", "<pre>foo bar</pre>");
test!(pre_lf_2, "<pre>\n\nfoo bar</pre>", "<pre>\nfoo bar</pre>");

test!(textarea_lf_0, "<textarea>foo bar</textarea>");
test!(
    textarea_lf_1,
    "<textarea>\nfoo bar</textarea>",
    "<textarea>foo bar</textarea>"
);
test!(
    textarea_lf_2,
    "<textarea>\n\nfoo bar</textarea>",
    "<textarea>\nfoo bar</textarea>"
);

test!(listing_lf_0, "<listing>foo bar</listing>");
test!(
    listing_lf_1,
    "<listing>\nfoo bar</listing>",
    "<listing>foo bar</listing>"
);
test!(
    listing_lf_2,
    "<listing>\n\nfoo bar</listing>",
    "<listing>\nfoo bar</listing>"
);

test!(comment_1, r#"<p>hi <!--world--></p>"#);
test!(comment_2, r#"<p>hi <!-- world--></p>"#);
test!(comment_3, r#"<p>hi <!--world --></p>"#);
test!(comment_4, r#"<p>hi <!-- world --></p>"#);

// FIXME: test serialization of qualified tag/attribute names that can't be
// parsed from HTML

test!(attr_ns_1, r#"<svg xmlns="bleh"></svg>"#);
test!(attr_ns_2, r#"<svg xmlns:foo="bleh"></svg>"#);
test!(attr_ns_3, r#"<svg xmlns:xlink="bleh"></svg>"#);
test!(attr_ns_4, r#"<svg xlink:href="bleh"></svg>"#);

test_no_parse!(malformed_tokens, r#"foo</div><div>"#);

#[test]
fn doctype() {
    let dom = parse_document(RcDom::default(), ParseOpts::default()).one("<!doctype html>");
    dom.document.children.borrow_mut().truncate(1); // Remove <html>
    let mut result = vec![];
    let document: SerializableHandle = dom.document.clone().into();
    serialize(&mut result, &document, Default::default()).unwrap();
    assert_eq!(String::from_utf8(result).unwrap(), "<!DOCTYPE html>");
}

#[test]
fn deep_tree() {
    let parser = parse_fragment(
        RcDom::default(),
        ParseOpts::default(),
        QualName::new(None, ns!(html), local_name!("div")),
        vec![],
    );
    let src = "<b>".repeat(60_000);
    let dom = parser.one(src);
    let opts = SerializeOpts::default();
    let mut ret_val = Vec::new();
    let document: SerializableHandle = dom.document.clone().into();
    serialize(&mut ret_val, &document, opts)
        .expect("Writing to a string shouldn't fail (expect on OOM)");
}