Hyperlink support

[sxyazi]

I'm using ansi-to-tui in Yazi (a file manager) to parse the ANSI sequences emitted by glow (a markdown renderer) for markdown preview, but the OSC 8 sequences get replaced with blanks, which isn't ideal, it'd be awesome if there were a way to keep those hyperlink texts.

Since the crate returns a Text and Text itself doesn't support hyperlinks and needs a hack to do so at the moment, maybe this requires ratatui/ratatui#902 getting resolved first? Or maybe it can export a custom widget, e.g. a wrapper of Text with that hack, to support more sequences?

[uttarayan21]

I see most ansi escape sequences starts with \x1b[ but osc 8 starts with \x1b] so we can probably parse it at the span level and since the style parser expects the former.

I'm not sure If we can mix ansi escape codes with osc 8 codes. From some initial testing I see that escape codes are printed verbatim in the terminal (in Kitty).

Perhaps we can keep the hyperlinks in the Span level and make something like HyperlinkedSpan and make HyperlinkedLine and HyperlinkedText wrappers that resemble the ones from ratatui-core. That does the rendering with the "hack" built into the type.

Also a few more questions I think we'll run into. :-

1. Is styling the link text possible with ansi codes (from very basic initial testing: No)
2. Do we maintain the style from before the link to text after the link
3. What happens in case of a broken / non terminated osc 8 sequences and how do we handle them.

[orhun]

Just leaving links of available widgets with OSC 8 support here:

• https://github.com/JayanAXHF/gitv/tree/main/crates/hyperrat
• https://github.com/benjajaja/tui-link

[uttarayan21]

@sxyazi Can you test this out and lmk if this works ?
The code still needs some cleanup which I'll try to do asap.

[sxyazi]

@uttarayan21 Thanks for working on this!

I'm using IntoText::into_text() to turn a String into a HyperlinkedText, but HyperlinkedText seems to be private and I can't reference it in my code - is this the correct way of doing it?

[uttarayan21]

Aah sorry I forgot to make the type public. I've pushed a commit to fix that.

[sxyazi]

Thanks for the fix!

Could you simplify HyperlinkedSpan a bit so its structure matches Span (apart from the new url field)? That way I can use a macro to handle both of them:

pub struct HyperlinkedSpan<'a> {
    /// The style of the span.
    pub style: Style,
    /// The content of the span as a Clone-on-write string.
    pub content: Cow<'a, str>,
    /// The URL associated with the span.
    pub url: Cow<'a, str>,
}

or with a generic type T:

pub struct HyperlinkedSpan<'a, T> {
    /// The style of the span.
    pub style: Style,
    /// The content of the span as a Clone-on-write string.
    pub content: Cow<'a, T>,
    /// The URL associated with the span.
    pub url: Cow<'a, T>,
}

Also, is it possible to also add a HyperlinkedParagraph that corresponds to Paragraph, so I can turn HyperlinkedText into a HyperlinkedParagraph to get the scrolling and wrapping it provides while still keeping the hyperlinks?

[uttarayan21]

That does makes much more sense than an enum. I've updated the span with this structure.

#[derive(Clone, Eq, PartialEq, Hash, Debug)]
pub struct HyperlinkedSpan<'a> {
    /// The style of the span.
    pub style: Style,
    /// The content of the span as a Clone-on-write string.
    pub content: Cow<'a, str>,
    /// The URL associated with the span.
    pub url: Option<Cow<'a, str>>,
}

I'll try to add a paragraph struct as well in the next commit.