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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162

use base::{Position, HTMLTagAttribute};


#[derive(Debug)]
pub struct HTMLTagAttributeIterator<'a> {
    pub html: &'a str,

    is_quote_start: bool,
    is_attribute_start: bool,
    is_get_attribute_name: bool,

    quote_char: u8,
    last_char: u8,
    last_index: usize,
    current_index: usize,
    value_start_index: usize,

    html_bytes: &'a [u8],
    html_len: usize,
}

impl<'a> HTMLTagAttributeIterator<'a> {
    fn new(html: &'a str) -> HTMLTagAttributeIterator<'a> {
        HTMLTagAttributeIterator {
            html: html,
            is_quote_start: false,
            is_attribute_start: false,
            is_get_attribute_name: false,
            quote_char: 0,
            last_char: 0,
            last_index: 0,
            current_index: 0,
            value_start_index: 0,
            html_bytes: html.as_bytes(),
            html_len: html.len()
        }
    }

    #[inline]
    fn finished_item(&mut self) {
        self.is_attribute_start = false;
        self.is_quote_start = false;
        self.is_get_attribute_name = false;
        self.last_index = self.current_index - 1;
    }
}

impl<'a> Iterator for HTMLTagAttributeIterator<'a> {
    type Item = (Position, HTMLTagAttribute);

    fn next(&mut self) -> Option<(Position, HTMLTagAttribute)> {
        while self.current_index < self.html_len {
            let c = self.html_bytes[self.current_index];
            if self.current_index > 0 {
                self.last_char = self.html_bytes[self.current_index - 1];;
            }
            self.current_index += 1;

            if self.is_attribute_start {

                if self.is_get_attribute_name {

                    if self.is_quote_start {
                        if c == self.quote_char {
                            // only when match the same `quote` char
                            if c == self.quote_char {
                                let name = &self.html[self.last_index..(self.value_start_index - 1)];
                                let value = &self.html[(self.value_start_index + 1)..(self.current_index - 1)];
                                let position = Position { start: self.last_index, end: self.current_index };
                                let attribute = HTMLTagAttribute {
                                    name: name.to_string(),
                                    value: value.to_string(),
                                };
                                self.finished_item();
                                return Some((position, attribute));
                            }
                        } else {
                            continue;
                        }
                    }

                    // quote start
                    if b'\'' == c || b'"' == c {
                        // only when the last char is `equal`
                        if b'=' == self.last_char {
                            self.is_quote_start = true;
                            self.quote_char = c;
                        }
                        continue;
                    }

                    // only when match a `blank` char
                    if c <= b' ' {
                        let name = &self.html[self.last_index..(self.value_start_index - 1)];
                        let value = &self.html[(self.value_start_index)..(self.current_index - 1)];
                        let position = Position { start: self.last_index, end: self.current_index - 1 };
                        let attribute = HTMLTagAttribute {
                            name: name.to_string(),
                            value: value.to_string(),
                        };
                        self.finished_item();
                        return Some((position, attribute));
                    }

                } else {

                    // only when match an `equal` char, start the attribute value
                    if b'=' == c {
                        self.value_start_index = self.current_index;
                        self.is_get_attribute_name = true;
                        continue;
                    }

                    // only when match an `blank` char, stop current attribute
                    if c <= b' ' {
                        let name = &self.html[self.last_index..(self.current_index - 1)];
                        let position = Position { start: self.last_index, end: self.current_index - 1 };
                        let attribute = HTMLTagAttribute {
                            name: name.to_string(),
                            value: "".to_string(),
                        };
                        self.finished_item();
                        return Some((position, attribute));
                    }

                }

            } else {

                // ignore `blank` char
                if c <= b' ' {
                    continue;
                }

                self.is_attribute_start = true;
                self.is_get_attribute_name = false;
                self.is_quote_start = false;
                self.last_index = self.current_index - 1;

            }
        }

        // the rest text
        if self.current_index > 1 && self.last_index < self.current_index - 1 {
            let name = &self.html[self.last_index..];
            let position = Position { start: self.last_index, end: self.current_index };
            let attribute = HTMLTagAttribute {
                name: name.to_string(),
                value: "".to_string()
            };
            self.finished_item();
            return Some((position, attribute));
        }

        return None;
    }
}

/// Return a HTMLTagAttribute Iterator
pub fn attr_iter(html: &str) -> HTMLTagAttributeIterator {
    HTMLTagAttributeIterator::new(html)
}