# Changelog

All notable changes to Fresco are documented here. The format is based on
[Keep a Changelog](https://keepachangelog.com/en/1.1.0/) and the project
adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## 0.1.0 — 2026-05-12

Initial release. Polished pan-zoom image viewer for Phoenix apps, with a
deliberate extension surface for layered libraries.

### Built-in viewer

- `<Fresco.viewer id src class>` LiveView function component
- Pan: click-drag, touch-drag, keyboard arrows
- Zoom: mouse wheel, pinch, double-click, dedicated buttons, `+` / `-` keys
- Fit-to-view initial state regardless of image / container aspect ratio
- Heroicons nav overlay at top-left: zoom-in, zoom-out, reset, fullscreen
- Viewport clamped so the image can't be panned off-screen
  (`visibilityRatio: 1.0`, `constrainDuringPan: true`)
- Smooth animations tuned for snappy responsiveness
  (`animationTime: 0.3`, `springStiffness: 10`)
- Browser fullscreen mode

### Extension surface

- `window.Fresco.viewerFor(domId)` — synchronous lookup of a live viewer handle
- `window.Fresco.onViewerReady(domId, callback)` — async-safe lookup that fires
  the callback as soon as the viewer is ready (handles mount-order races
  when an extension hook mounts before its host viewer)
- `window.Fresco.registerSourceProvider(predicate, factory)` — registers a
  predicate-matched URL transformer; first registered provider that matches
  wins, falling back to a default plain-image provider
- Viewer handle exposes: `imageToScreen` / `screenToImage`,
  `getViewportBounds`, `fitBounds`, `setSource`,
  `swapSourcePreservingBounds`, and `on(event, handler)` for `zoom` / `pan`
  / `open` / `resize` events

### JS engine

- OpenSeadragon ~> 4.1 lazy-loaded from jsDelivr on first mount
- One bundled JS file (`priv/static/fresco.js`); no npm dep, no build step
  in consumer apps
- Heroicons SVGs inlined; no PNG sprite dance against a CDN

### Requirements

- `phoenix_live_view ~> 1.1`, `phoenix_html ~> 4.0`, `jason ~> 1.4`