1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137

// 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.

//! High-level interface to the parser.

use crate::buffer_queue::BufferQueue;
use crate::tokenizer::{Tokenizer, TokenizerOpts, TokenizerResult};
use crate::tree_builder::{create_element, TreeBuilder, TreeBuilderOpts, TreeSink};
use crate::{Attribute, QualName};

use std::borrow::Cow;

use crate::tendril;
use crate::tendril::stream::{TendrilSink, Utf8LossyDecoder};
use crate::tendril::StrTendril;

/// All-encompassing options struct for the parser.
#[derive(Clone, Default)]
pub struct ParseOpts {
    /// Tokenizer options.
    pub tokenizer: TokenizerOpts,

    /// Tree builder options.
    pub tree_builder: TreeBuilderOpts,
}

/// Parse an HTML document
///
/// The returned value implements `tendril::TendrilSink`
/// so that Unicode input may be provided incrementally,
/// or all at once with the `one` method.
///
/// If your input is bytes, use `Parser::from_utf8`.
pub fn parse_document<Sink>(sink: Sink, opts: ParseOpts) -> Parser<Sink>
where
    Sink: TreeSink,
{
    let tb = TreeBuilder::new(sink, opts.tree_builder);
    let tok = Tokenizer::new(tb, opts.tokenizer);
    Parser {
        tokenizer: tok,
        input_buffer: BufferQueue::default(),
    }
}

/// Parse an HTML fragment
///
/// The returned value implements `tendril::TendrilSink`
/// so that Unicode input may be provided incrementally,
/// or all at once with the `one` method.
///
/// If your input is bytes, use `Parser::from_utf8`.
pub fn parse_fragment<Sink>(
    sink: Sink,
    opts: ParseOpts,
    context_name: QualName,
    context_attrs: Vec<Attribute>,
) -> Parser<Sink>
where
    Sink: TreeSink,
{
    let context_elem = create_element(&sink, context_name, context_attrs);
    parse_fragment_for_element(sink, opts, context_elem, None)
}

/// Like `parse_fragment`, but with an existing context element
/// and optionally a form element.
pub fn parse_fragment_for_element<Sink>(
    sink: Sink,
    opts: ParseOpts,
    context_element: Sink::Handle,
    form_element: Option<Sink::Handle>,
) -> Parser<Sink>
where
    Sink: TreeSink,
{
    let tb = TreeBuilder::new_for_fragment(sink, context_element, form_element, opts.tree_builder);
    let tok_opts = TokenizerOpts {
        initial_state: Some(tb.tokenizer_state_for_context_elem()),
        ..opts.tokenizer
    };
    let tok = Tokenizer::new(tb, tok_opts);
    Parser {
        tokenizer: tok,
        input_buffer: BufferQueue::default(),
    }
}

/// An HTML parser,
/// ready to receive Unicode input through the `tendril::TendrilSink` trait’s methods.
pub struct Parser<Sink>
where
    Sink: TreeSink,
{
    pub tokenizer: Tokenizer<TreeBuilder<Sink::Handle, Sink>>,
    pub input_buffer: BufferQueue,
}

impl<Sink: TreeSink> TendrilSink<tendril::fmt::UTF8> for Parser<Sink> {
    fn process(&mut self, t: StrTendril) {
        self.input_buffer.push_back(t);
        // FIXME: Properly support </script> somehow.
        while let TokenizerResult::Script(_) = self.tokenizer.feed(&self.input_buffer) {}
    }

    // FIXME: Is it too noisy to report every character decoding error?
    fn error(&mut self, desc: Cow<'static, str>) {
        self.tokenizer.sink.sink.parse_error(desc)
    }

    type Output = Sink::Output;

    fn finish(self) -> Self::Output {
        // FIXME: Properly support </script> somehow.
        while let TokenizerResult::Script(_) = self.tokenizer.feed(&self.input_buffer) {}
        assert!(self.input_buffer.is_empty());
        self.tokenizer.end();
        self.tokenizer.sink.sink.finish()
    }
}

impl<Sink: TreeSink> Parser<Sink> {
    /// Wrap this parser into a `TendrilSink` that accepts UTF-8 bytes.
    ///
    /// Use this when your input is bytes that are known to be in the UTF-8 encoding.
    /// Decoding is lossy, like `String::from_utf8_lossy`.
    #[allow(clippy::wrong_self_convention)]
    pub fn from_utf8(self) -> Utf8LossyDecoder<Self> {
        Utf8LossyDecoder::new(self)
    }
}