sofie_engine/
page.rs

1use crate::asset::{Asset, CLIENT_SCRIPT, ENGINE_SCRIPT, STYLESHEET};
2use crate::escape::push_escaped;
3use crate::language::Language;
4
5/// `allowEval` off removes eval paths, indicator styles off avoid an inline `<style>` the CSP
6/// blocks, and a zero history cache keeps personal data out of `localStorage`. Only a 5xx is an
7/// error htmx logs: the server sends 4xx as notices placed by `HX-Retarget`.
8const HTMX_CONFIG: &str = r#"<meta name="htmx-config" content='{"allowEval":false,"allowScriptTags":false,"selfRequestsOnly":true,"includeIndicatorStyles":false,"historyCacheSize":0,"responseHandling":[{"code":"204","swap":false},{"code":"[234]..","swap":true},{"code":"5..","swap":true,"error":true}]}'>"#;
9
10macro_rules! notice_region_open {
11    ($($attribute:literal)?) => {
12        concat!("<div id=\"sofie-notice\" role=\"status\" aria-live=\"polite\"", $(" ", $attribute,)?)
13    };
14}
15
16pub const NOTICE_TARGET: &str = "#sofie-notice";
17
18const TITLE_OPEN: &str = "<title>";
19const TITLE_CLOSE: &str = "</title>";
20
21/// Around what `<Head>` writes, which the page moves into `<head>`.
22#[cfg(feature = "content")]
23pub(crate) const HEAD_START: &str = "<!--sofie-head-->";
24#[cfg(feature = "content")]
25pub(crate) const HEAD_END: &str = "<!--/sofie-head-->";
26
27/// So a notice from an earlier failure does not outlive the next success.
28pub(crate) const CLEARED_NOTICE: &str =
29    concat!(notice_region_open!("hx-swap-oob=\"true\""), "></div>");
30
31/// engine.js's own notices: the attribute it reads, the key, and its English fallback.
32const SCRIPT_NOTICES: [(&str, &str, &str); 5] = [
33    (
34        "data-unreachable",
35        "notice.unreachable",
36        "The server could not be reached. Try again.",
37    ),
38    (
39        "data-failed",
40        "notice.failed",
41        "Something went wrong. Try again.",
42    ),
43    (
44        "data-passkey-refused",
45        "notice.passkey_refused",
46        "The passkey was not accepted. Try again.",
47    ),
48    (
49        "data-passkey-unsupported",
50        "notice.passkey_unsupported",
51        "This browser cannot use passkeys.",
52    ),
53    (
54        "data-passkey-unused",
55        "notice.passkey_unused",
56        "The passkey was not used. Try again.",
57    ),
58];
59
60#[derive(Debug)]
61pub struct Page<'a> {
62    pub title: &'a str,
63    pub lang: &'a str,
64    pub body: &'a str,
65    /// Such as why a form posted without JavaScript was refused.
66    pub notice: &'a [String],
67    pub nonce: &'a str,
68    pub islands: Option<&'a IslandLinks>,
69    pub script_notices: ScriptNotices<'a>,
70}
71
72/// What engine.js says when a request fails, in the page's language.
73#[derive(Clone, Copy, Debug)]
74pub struct ScriptNotices<'a>(Language<'a>);
75
76impl ScriptNotices<'static> {
77    #[must_use]
78    pub fn plain() -> Self {
79        Self(Language::plain())
80    }
81}
82
83#[cfg(feature = "i18n")]
84impl<'a> ScriptNotices<'a> {
85    #[must_use]
86    pub fn new(language: crate::Language<'a>) -> Self {
87        Self(language)
88    }
89}
90
91impl ScriptNotices<'_> {
92    /// English is the script's own, so a page in English carries none.
93    fn push_attributes(self, html: &mut String) {
94        for (attribute, key, english) in SCRIPT_NOTICES {
95            let text = self.0.text(key, english);
96            if text != english {
97                html.push(' ');
98                html.push_str(attribute);
99                html.push_str("=\"");
100                push_escaped(html, text);
101                html.push('"');
102            }
103        }
104    }
105}
106
107/// Outside the `islands` feature, so a `Page` has the same fields whichever crates enable it.
108#[derive(Clone, Debug, PartialEq, Eq)]
109pub struct IslandLinks {
110    pub script: String,
111    pub stylesheet: String,
112}
113
114impl IslandLinks {
115    pub(crate) fn push_head(&self, html: &mut String, nonce: &str) {
116        html.push_str("<link rel=\"stylesheet\" href=\"");
117        push_escaped(html, &self.stylesheet);
118        html.push_str("\" data-sofie-islands><script type=\"module\" src=\"");
119        push_escaped(html, &self.script);
120        html.push_str("\" nonce=\"");
121        push_escaped(html, nonce);
122        html.push_str("\" data-sofie-islands></script>");
123    }
124}
125
126impl Page<'_> {
127    #[must_use]
128    pub fn render(&self) -> String {
129        let (head, before, after) = self.split_head();
130        let (title, body) = take_title([before, after]);
131        let mut html = String::with_capacity(self.body.len() + 900);
132        html.push_str("<!doctype html><html lang=\"");
133        push_escaped(&mut html, self.lang);
134        html.push_str(
135            "\"><head><meta charset=\"utf-8\">\
136             <meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">",
137        );
138        if let Some(title) = title {
139            html.push_str(title);
140        } else if !head.starts_with(TITLE_OPEN) {
141            html.push_str(TITLE_OPEN);
142            push_escaped(&mut html, self.title);
143            html.push_str(TITLE_CLOSE);
144        }
145        html.push_str(head);
146        html.push_str(HTMX_CONFIG);
147        html.push_str("<link rel=\"stylesheet\" href=\"");
148        STYLESHEET.push_path(&mut html);
149        html.push_str("\">");
150        self.push_script(&mut html, CLIENT_SCRIPT);
151        self.push_script(&mut html, ENGINE_SCRIPT);
152        if let Some(islands) = self.islands {
153            islands.push_head(&mut html, self.nonce);
154        }
155        html.push_str("</head><body>");
156        html.push_str(notice_region_open!());
157        self.script_notices.push_attributes(&mut html);
158        html.push('>');
159        push_notice(&mut html, self.notice);
160        html.push_str("</div>");
161        for part in body {
162            html.push_str(part);
163        }
164        html.push_str("</body></html>");
165        html
166    }
167
168    /// What a `<Head>` wrote, and the body before and after it.
169    #[cfg(feature = "content")]
170    fn split_head(&self) -> (&str, &str, &str) {
171        let body = self.body;
172        let found = body.find(HEAD_START).and_then(|start| {
173            let end = start + body[start..].find(HEAD_END)?;
174            Some((start, end))
175        });
176        let Some((start, end)) = found else {
177            return ("", body, "");
178        };
179        (
180            &body[start + HEAD_START.len()..end],
181            &body[..start],
182            &body[end + HEAD_END.len()..],
183        )
184    }
185
186    #[cfg(not(feature = "content"))]
187    fn split_head(&self) -> (&str, &str, &str) {
188        ("", self.body, "")
189    }
190
191    /// An asset path is the engine's own text and needs no escaping.
192    fn push_script(&self, html: &mut String, script: Asset) {
193        html.push_str("<script src=\"");
194        script.push_path(html);
195        html.push_str("\" nonce=\"");
196        push_escaped(html, self.nonce);
197        html.push_str("\" defer></script>");
198    }
199}
200
201/// A template's `<title>` and the body around it. Data is escaped and the parser lets a template
202/// write one `<title>` outside an `<svg>`, at its top level, so the first outside one is the
203/// template's; one inside names its image.
204fn take_title([before, after]: [&str; 2]) -> (Option<&str>, [&str; 3]) {
205    if let Some((title, start, end)) = split_title(before) {
206        return (Some(title), [start, end, after]);
207    }
208    if let Some((title, start, end)) = split_title(after) {
209        return (Some(title), [before, start, end]);
210    }
211    (None, [before, after, ""])
212}
213
214fn split_title(body: &str) -> Option<(&str, &str, &str)> {
215    let start = first_title_outside_svg(body)?;
216    let end = start + body[start..].find(TITLE_CLOSE)? + TITLE_CLOSE.len();
217    Some((&body[start..end], &body[..start], &body[end..]))
218}
219
220fn first_title_outside_svg(body: &str) -> Option<usize> {
221    let mut svg_depth = 0_isize;
222    for (start, _) in body.match_indices('<') {
223        let tag = &body[start..];
224        if tag.starts_with("<svg") {
225            svg_depth += 1;
226        } else if tag.starts_with("</svg>") {
227            svg_depth -= 1;
228        } else if svg_depth == 0 && tag.starts_with(TITLE_OPEN) {
229            return Some(start);
230        }
231    }
232    None
233}
234
235#[must_use]
236pub fn with_cleared_notice(mut fragment: String) -> String {
237    fragment.push_str(CLEARED_NOTICE);
238    fragment
239}
240
241#[must_use]
242pub fn notice(messages: &[impl AsRef<str>]) -> String {
243    let mut html = String::new();
244    push_notice(&mut html, messages);
245    html
246}
247
248fn push_notice(html: &mut String, messages: &[impl AsRef<str>]) {
249    for message in messages {
250        html.push_str("<p>");
251        push_escaped(html, message.as_ref());
252        html.push_str("</p>");
253    }
254}
255
256#[cfg(test)]
257mod tests {
258    use super::*;
259
260    #[test]
261    fn the_notice_region_and_its_target_name_the_same_element() {
262        let id = NOTICE_TARGET.trim_start_matches('#');
263        assert!(notice_region_open!().contains(&format!("id=\"{id}\"")));
264        assert!(CLEARED_NOTICE.contains(&format!("id=\"{id}\"")));
265    }
266
267    fn page(script_notices: ScriptNotices<'_>) -> String {
268        Page {
269            title: "Orders",
270            lang: "tr",
271            body: "",
272            notice: &[],
273            nonce: "n",
274            islands: None,
275            script_notices,
276        }
277        .render()
278    }
279
280    #[test]
281    fn an_english_page_leaves_the_script_s_notices_to_it() {
282        assert!(page(ScriptNotices::plain()).contains("aria-live=\"polite\"></div>"));
283    }
284
285    #[cfg(feature = "i18n")]
286    #[test]
287    fn the_script_s_notices_are_written_in_the_page_s_language() {
288        let translations = crate::Translations::new(&["en", "tr"]).unwrap();
289        let turkish = translations.negotiate(None, Some("tr"));
290
291        let html = page(ScriptNotices::new(turkish));
292
293        assert!(
294            html.contains(
295                "<div id=\"sofie-notice\" role=\"status\" aria-live=\"polite\" \
296                 data-unreachable=\"Sunucuya ulaşılamadı. Lütfen yeniden deneyin.\" \
297                 data-failed=\"Bir şeyler ters gitti. Lütfen yeniden deneyin.\""
298            ),
299            "{html}"
300        );
301        assert!(html.contains("data-passkey-unused=\"Geçiş anahtarı kullanılmadı."));
302    }
303
304    #[test]
305    fn the_title_is_the_first_one_outside_every_svg() {
306        let body = "<svg><title>Icon</title><svg><title>Inner</title></svg></svg>\
307                    <title>Orders</title><svg><title>Row</title></svg>";
308
309        let (title, before, after) = split_title(body).unwrap();
310
311        assert_eq!(title, "<title>Orders</title>");
312        assert!(before.ends_with("</svg></svg>"));
313        assert_eq!(after, "<svg><title>Row</title></svg>");
314    }
315
316    #[test]
317    fn a_title_only_inside_svgs_is_no_page_title() {
318        assert!(split_title("<svg><title>Icon</title></svg><p>Text</p>").is_none());
319    }
320
321    #[test]
322    fn a_fragment_carries_an_out_of_band_empty_notice() {
323        let html = with_cleared_notice("<table></table>".to_owned());
324        assert!(html.starts_with("<table></table><div id=\"sofie-notice\""));
325        assert!(html.ends_with("hx-swap-oob=\"true\"></div>"));
326    }
327}
sofie_engine/page.rs

sofie_engine/
page.rs
