1 use super::{FontData, FontFamily, FontStyle, LayoutBox};
2 use wasm_bindgen::JsCast;
3 use web_sys::{window, HtmlElement};
4 
5 #[derive(Debug, Clone)]
6 pub enum FontError {
7     UnknownError,
8 }
9 
10 impl std::fmt::Display for FontError {
fmt(&self, fmt: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error>11     fn fmt(&self, fmt: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
12         match self {
13             _ => write!(fmt, "Unknown error"),
14         }
15     }
16 }
17 
18 impl std::error::Error for FontError {}
19 
20 #[derive(Clone)]
21 pub struct FontDataInternal(String, String);
22 
23 impl FontData for FontDataInternal {
24     type ErrorType = FontError;
new(family: FontFamily, style: FontStyle) -> Result<Self, FontError>25     fn new(family: FontFamily, style: FontStyle) -> Result<Self, FontError> {
26         Ok(FontDataInternal(
27             family.as_str().into(),
28             style.as_str().into(),
29         ))
30     }
estimate_layout(&self, size: f64, text: &str) -> Result<LayoutBox, Self::ErrorType>31     fn estimate_layout(&self, size: f64, text: &str) -> Result<LayoutBox, Self::ErrorType> {
32         let window = window().unwrap();
33         let document = window.document().unwrap();
34         let body = document.body().unwrap();
35         let span = document.create_element("span").unwrap();
36         span.set_text_content(Some(text));
37         span.set_attribute("style", &format!("display: inline-block; font-family:{}; font-size: {}px; position: fixed; top: 100%", self.0, size)).unwrap();
38         let span = span.into();
39         body.append_with_node_1(&span).unwrap();
40         let elem = JsCast::dyn_into::<HtmlElement>(span).unwrap();
41         let height = elem.offset_height() as i32;
42         let width = elem.offset_width() as i32;
43         elem.remove();
44         Ok(((0, 0), (width, height)))
45     }
46 }
47