# Types

Import these from `@grafloria/engine`.

## Types

### `CompoundAlgorithm`

Also has every member of `String`, listed on its own entry.

Any registered layout name, or the built-in grid.

```ts
type CompoundAlgorithm = 'grid' | 'dagre' | 'elk' | (string & {});
```

### `ConstraintType`

Also has every member of `String`, listed on its own entry.

Types of layout constraints that can be applied to nodes

```ts
type ConstraintType = 'pin' | 'fix-x' | 'fix-y' | 'boundary';
```

### `EdgeBundlingStrategy`

Also has every member of `String`, listed on its own entry.

Bundling strategy

```ts
type EdgeBundlingStrategy = 'stub' | 'force-directed' | 'hierarchical' | 'none';
```

### `ELKAlgorithm`

Also has every member of `String`, listed on its own entry.

ELK layout algorithms

```ts
type ELKAlgorithm =
  | 'layered'
  | 'force'
  | 'stress'
  | 'mrtree'
  | 'radial'
  | 'disco';
```

### `ElkPortConstraint`

Also has every member of `String`, listed on its own entry.

```ts
type ElkPortConstraint = 'FREE' | 'FIXED_SIDE' | 'FIXED_ORDER' | 'FIXED_POS';
```

### `ElkPortSide`

Also has every member of `String`, listed on its own entry.

ELK's compass vocabulary for a port side.

```ts
type ElkPortSide = 'NORTH' | 'EAST' | 'SOUTH' | 'WEST';
```

### `FlowDirection`

Also has every member of `String`, listed on its own entry.

```ts
type FlowDirection = 'TB' | 'BT' | 'LR' | 'RL';
```

### `GraphLayoutFn`

The contract a layout must satisfy to be packable: nodes + links in, positions
out. Deliberately array-based (not DiagramModel-based) — a component is a
SUBSET of a diagram, and there is no such thing as a sub-DiagramModel.

```ts
type GraphLayoutFn = (
  nodes: NodeModel[],
  links: LinkModel[],
  options: UnifiedLayoutOptions
) => Promise<LayoutResult> | LayoutResult;
```

### `IncrementalLayoutStrategy`

Also has every member of `String`, listed on its own entry.

Strategy for incremental layout

```ts
type IncrementalLayoutStrategy =
  | 'pin-existing'
  | 'fix-anchors'
  | 'proximity-aware'
  | 'minimal-shift';
```

### `LayoutAlgorithmType`

Also has every member of `String`, listed on its own entry.

Layout algorithm types

```ts
type LayoutAlgorithmType = 'grid' | 'force-directed' | 'hierarchical' | 'hybrid';
```

### `LayoutEventType`

Also has every member of `String`, listed on its own entry.

Layout event types

```ts
type LayoutEventType =
  | 'layout:started'
  | 'layout:completed'
  | 'layout:failed'
  | 'layout:algorithm-changed'
  | 'layout:node-placed';
```

### `LayoutMode`

Also has every member of `String`, listed on its own entry.

Layout mode for automatic vs manual positioning

```ts
type LayoutMode = 'auto' | 'manual';
```

### `LayoutRequest`

Also has every member of `LayoutRequestRun`, listed on its own entry.

```ts
type LayoutRequest = LayoutRequestRun | LayoutRequestCancel;
```

### `LayoutResponse`

Also has every member of `LayoutProgressMessage`, listed on its own entry.

```ts
type LayoutResponse =
  | LayoutProgressMessage
  | LayoutResultMessage
  | LayoutErrorMessage;
```

### `LayoutStopReason`

Also has every member of `String`, listed on its own entry.

Why a run stopped early. Absent when it ran to completion.

```ts
type LayoutStopReason = 'cancelled' | 'timeout' | 'iteration-cap';
```

### `LayoutWireOptions`

Also has every member of `LayoutOptions`, listed on its own entry.

Options as they cross the wire: the named ones, plus whatever adapter-specific
knobs the caller supplied (`iterations`, `repulsion`, `rankdir`, …). Anything
here must be structured-clone-safe — `stripNonClonable` enforces that at the
seam rather than trusting callers to.

```ts
type LayoutWireOptions = Partial<LayoutOptions> & Record<string, unknown>;
```

### `PortConstraintMode`

Also has every member of `String`, listed on its own entry.

How much freedom does the layout engine have over this node's ports?

FREE        — no declared ports: put the edge wherever it routes best. FIXED_SIDE  — the author said which side; the engine may still reorder
                within that side to reduce crossings. FIXED_ORDER — side AND order are the author's. FIXED_POS   — the exact coordinates are the author's.

`'auto'` (the default) resolves per node: FIXED_SIDE when the node declares
ports, FREE when it does not. That is what makes port-awareness safe to leave
ON — it constrains only the nodes whose author asked for it.

```ts
type PortConstraintMode = 'auto' | 'free' | 'fixed-side' | 'fixed-order' | 'fixed-pos';
```

### `PortFlowDirection`

Also has every member of `String`, listed on its own entry.

Port direction (input or output)

```ts
type PortFlowDirection = 'input' | 'output' | 'bidirectional';
```

### `PortSide`

Also has every member of `String`, listed on its own entry.

Port side relative to node

```ts
type PortSide = 'left' | 'right' | 'top' | 'bottom';
```