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

use failure::Error;
use oatie::doc::*;
use oatie::rtf::*;
use oatie::stepper::DocStepper;
use pulldown_cmark::{
    Event,
    Tag,
};
use pulldown_cmark_to_cmark::fmt::cmark;

struct DocToMarkdown<'a, 'b> {
    doc_stepper: DocStepper<'a, RtfSchema>,
    queue: Vec<Event<'b>>,
}

impl<'a, 'b> DocToMarkdown<'a, 'b> {
    fn new(doc: &'a DocSpan<RtfSchema>) -> Self {
        DocToMarkdown {
            doc_stepper: DocStepper::new(doc),
            queue: vec![],
        }
    }
}

impl<'a, 'b> Iterator for DocToMarkdown<'a, 'b> {
    type Item = Event<'b>;

    fn next(&mut self) -> Option<Event<'b>> {
        if self.queue.len() > 0 {
            return Some(self.queue.remove(0));
        }

        match self.doc_stepper.head() {
            Some(DocGroup(ref attrs, ref body)) => {
                let res = Some(match attrs {
                    Attrs::Para => Event::Start(Tag::Paragraph),
                    Attrs::Header(level) => Event::Start(Tag::Header(*level as i32)),
                    Attrs::Code => Event::Start(Tag::CodeBlock("".into())),
                    Attrs::Html => {
                        let mut out = String::new();
                        for child in body {
                            match *child {
                                DocText(_, ref text) => {
                                    out.push_str(text.as_str());
                                }
                                _ => {}
                            }
                        }
                        self.doc_stepper.next();
                        return Some(Event::Html(out.into()));
                    }
                    Attrs::ListItem => {
                        if let Some(DocGroup(ref pre_attrs, _)) = self.doc_stepper.unhead() {
                            if *pre_attrs != Attrs::ListItem {
                                self.doc_stepper.enter();
                                return Some(Event::Start(Tag::Item));
                            }
                        }
                        self.queue.push(Event::Start(Tag::Item));
                        Event::Start(Tag::List(None))
                    }
                    Attrs::Caret { .. } => {
                        self.doc_stepper.next();
                        return self.next();
                    }
                    Attrs::Rule => Event::Start(Tag::Rule),
                    // _ => {
                    //     eprintln!("Unexpected tag {:?}!", attrs);
                    //     self.doc_stepper.next();
                    //     return self.next();
                    // }
                });
                self.doc_stepper.enter();
                res
            }
            Some(DocText(ref styles, ref text)) => {
                // Styling.
                let text_event = Event::Text(text.to_string().replace("\n", "  \n").into());
                let res = if styles.contains(&RtfStyle::Bold) {
                    self.queue.push(text_event);
                    self.queue.push(Event::End(Tag::Strong));
                    Some(Event::Start(Tag::Strong))
                } else {
                    Some(text_event)
                };

                self.doc_stepper.next();
                res
            }
            None => {
                if self.doc_stepper.is_done() {
                    None
                } else {
                    let mut stepper_clone = self.doc_stepper.clone();
                    stepper_clone.unenter();
                    let attrs = match stepper_clone.head() {
                        Some(DocGroup(ref attrs, _)) => attrs.clone(),
                        _ => unreachable!(),
                    };
                    self.doc_stepper.exit();
                    Some(match attrs {
                        Attrs::Para => Event::End(Tag::Paragraph),
                        Attrs::Header(level) => Event::End(Tag::Header(level as i32)),
                        Attrs::Code => {
                            self.queue.push(Event::End(Tag::CodeBlock("".into())));
                            Event::Text("\n".to_string().into())
                        }
                        Attrs::ListItem => {
                            if let Some(DocGroup(ref post_attrs, _)) = self.doc_stepper.head() {
                                if *post_attrs != Attrs::ListItem {
                                    self.queue.push(Event::End(Tag::List(None)));
                                }
                            }
                            Event::End(Tag::Item)
                        }
                        Attrs::Rule => Event::End(Tag::Rule),
                        _ => unimplemented!(),
                    })
                }
            }
        }
    }
}

pub fn doc_to_markdown(doc: &DocSpan<RtfSchema>) -> Result<String, Error> {
    let to_mark = DocToMarkdown::new(&doc);
    let mut buf = String::new();
    cmark(to_mark, &mut buf, None)?;
    Ok(buf)
}