nordisk/facett

facett-markdown — design note

Status: builds (egui 0.33) + 5 tests green. In ordning/crates/widgets/facett-markdown; destined for facett.

What it is

A Markdown editor + preview for case descriptions and comments, with @mention and #tag extraction (for the host to link/notify) and highlighting. Edit/Preview toggle. A pragmatic, dependency-free renderer (no markdown crate — the subset a case uses is small; hand-rolling keeps the lean-Rust stance).

API

let mut md = Markdown::new("Description").with_text("# Title\n@maria see #regression");
md.ui(ui);                       // edit/preview
let people = md.mentions();      // ["maria"]   (unique, first-seen order, Swedish letters OK)
let tags   = md.tags();          // ["regression"]
let source = md.text();

Rendering subset

Headings (#/##/###), bullet + numbered lists, blockquotes (>), code fences (```), and inline bold, code, [text](url) links, @mention, #tag. Rendered via egui LayoutJob for mixed inline styles.

Design decisions

• @/# must start a word (so user@example.com and foo#bar are NOT mentions/tags); word chars include Swedish åäöÅÄÖ + _-. Tested.
• Links/headings use the Tillsynia-yellow accent; mentions blue, tags green, code on a dark bg.
• state_json exposes mode, char count, mentions, tags → headless-observable.

Move-to-facett / TODO

• Bold currently isn't truly bold (egui needs a bold font variant) — emulated; the facett version uses the theme's strong font. Same for theme-driven colors.
• @mention / #tag autocomplete dropdown while typing in edit mode (needs the host's user/tag list).
• Tables, images, task-list checkboxes; or swap to pulldown-cmark if the subset proves too small — but the current hand-rolled renderer has zero deps, which fits the lean stance.