# evidence-binder

`@citation-evidence/evidence-binder` — connect evidence items to structured
targets (form fields, claims, requirements, …) and render the visual guide that
ties a target, its evidence card, and the source highlight together.

This is the canonical home of the binder implementation, extracted from
`citation-evidence/src/binder/` (EBIND-WP-0001).

## What this package owns

- **Evidence links** — `EvidenceLink` repository + binding service
  (`services/bindings.ts`, `repos/in-memory-links.ts`). Two query directions:
  *all evidence for a target* and *all targets for an evidence item*. Emits the
  canonical engine bus events (`EvidenceLinkCreated/Updated/Removed`,
  `EvidenceItemActivated`).
- **Active state** — the `(activeTarget, activeEvidenceItemId, activeAnnotationId)`
  machine and React provider (`state/active.ts`) that the form UI, evidence
  sidebar, and viewer adapter coordinate through.
- **Rect registry contract** (SharedContracts §7) — a single registry into which
  independent renderers publish `field` / `evidence-card` / `highlight` rects,
  plus the change pumps, React hooks, and the SVG `Overlay` that draws the guide
  (`visual-guide/`).
- **Reference form UI** — `FormRenderer` and `FieldDefinitionForm`, kept as
  supported, target-neutral exports (see `docs/adr/ADR-0001-reference-ui-surface.md`).

`BinderProvider` composes all four concerns behind one mount.

## Dependency boundary

Per `citation-evidence/wiki/DependencyMap.md` §2, this package **may** depend on
`citation-engine` and `evidence-anchor`, and **must not** depend on
`evidence-source`, `citation-work`, or the umbrella `citation-evidence`. The MVP
slice imports only `citation-engine` (shared types + event bus). The boundary is
enforced by `eslint.config.js`. Shared-contract authority stays in the umbrella
wiki.

## Develop

```bash
pnpm install        # links @citation-evidence/engine from ../citation-engine
pnpm test           # vitest (node + happy-dom suites)
pnpm typecheck      # tsc -b --noEmit
pnpm lint           # eslint (enforces the dependency boundary)
```

Requires a sibling checkout of `citation-engine` (see `.nvmrc` for the Node
version). See `docs/extraction-inventory.md` for the extraction boundary and
resolved contract deltas.