fusion/plugins/fusion-plugin-dependency-graph/README.md

fusion-plugin-dependency-graph

Plugin-provided top-level Graph dashboard view for Fusion.

Host registration and bundled loading

The dependency graph view is registered as a bundled plugin view in the dashboard. This means:

• registerBundledPluginViews() (called at dashboard startup) registers the view component in the static plugin view registry under key plugin:fusion-plugin-dependency-graph:graph.
• The view component is resolved via a literal-specifier lazy import (import("@fusion-plugin-examples/dependency-graph/dashboard-view")) — this is critical for Vite/esbuild to emit a production chunk.
• In Vite dev/build and Vitest, @fusion-plugin-examples/dependency-graph/dashboard-view is aliased to plugins/fusion-plugin-dependency-graph/src/dashboard-view.tsx (source, not dist/). This avoids stale dist artifacts breaking the dashboard view.
• The App.tsx graph route resolves to the bundled view via isPluginViewRegistered fallback, so the graph view works even when the plugin is not installed/loaded through the PluginLoader API (e.g. fresh DB).
• The canonical route ID is plugin:fusion-plugin-dependency-graph:graph.

Rendering approach

• Filtering: includes triage, todo, in-progress, in-review; excludes done, archived
• Graph build: edges are resolved only from task.dependencies as source=dependent, target=dependency
• Orphan dependency handling: if a visible task depends on an excluded/missing dependency (for example done/archived after filtering), the missing edge is silently dropped and graph rendering continues without broken connectors
• Auto-layout: Sugiyama-style layered layout (computeAutoLayout) groups nodes by dependency depth and spaces layers consistently
• Edge drawing: SVG bezier curves from source bottom-center to target top-center, with arrowheads showing dependent → dependency direction
• Interaction: drag-to-pan canvas background, drag-to-reposition nodes, cursor-centered wheel zoom, pinch-to-zoom with stationary midpoint, keyboard shortcuts, zoom toolbar, reset, and fit-to-graph
• Fit-to-graph: computes node bounding box with layout node dimensions and applies zoom/pan so the graph fits in viewport with padding
• Initial auto-fit: when no saved scoped positions exist, the first non-empty render auto-fits once; subsequent updates preserve user navigation state
• Position persistence: dragged node positions are stored per project in browser localStorage and restored on reload
• Animated transitions: fit/reset operations animate transform (var(--transition-normal)), while continuous drag/wheel/pinch stays transition-free for responsiveness
• Node rendering: each graph node renders the real dashboard TaskCard via GraphTaskNode (no duplicated card markup)
• Task detail integration: a primary non-drag click on a graph node surface opens the native dashboard task detail modal exactly once through host context (openTaskDetail), matching board/list behavior
• In-progress behavior: steps are visible by default and active-task glow (agent-active) is preserved because node cards reuse TaskCard directly
• Active-state indicator bar: active nodes render a compact top bar (.graph-task-active-indicator) with the current execution status label (for example Executing, Planning) and pulsing --in-progress emphasis
• Current-step highlighting: active nodes set data-current-step for valid native step indices so CSS selectors highlight the currently executing .card-step-item and pulse its step dot
• Zoom-out differentiation: .graph-task-node--active adds amplified glow and subtle scale/border tint so active nodes remain distinguishable at reduced zoom levels
• In-review visual treatment: in-review nodes get a static .graph-task-node--in-review left accent in --in-review to distinguish waiting-review work from active execution nodes
• Graph node classes: .graph-task-node, .graph-task-node--active, .graph-task-node--in-review, .graph-task-node--highlighted, .graph-task-node--dimmed, .graph-node--highlighted, and .graph-node--dimmed are available for graph-specific layering/highlight states while card internals remain owned by TaskCard.css
• Graph edge classes: .graph-edge--highlighted and .graph-edge--dimmed are applied during dependency-chain emphasis states
• Drag behavior: graph nodes pass disableDrag={true} to TaskCard so card-level HTML5 drag does not conflict with canvas pan/zoom

Position persistence

• Canonical base key: fusion-plugin-dependency-graph:positions
• Storage key format: kb:${projectId}:fusion-plugin-dependency-graph:positions (falls back to fusion-plugin-dependency-graph:positions when no project is selected)
• Read path: positions load on graph mount and whenever projectId changes, then merge with fresh auto-layout so new tasks still receive layout defaults
• Write path: positions persist on drag end only (not on every drag frame), filtered to currently visible tasks for stale cleanup
• Reset behavior: Fit to graph / Reset view clear persisted positions and re-apply auto-layout
• Implementation detail: the plugin now reuses dashboard projectStorage helpers (getScopedItem / setScopedItem / removeScopedItem) instead of duplicating scoped localStorage logic

Dependency chain highlighting

• Hover a node to highlight the full transitive upstream + downstream chain for that task.
• Click a node to persist selection highlighting until the same node is clicked again or the canvas pane is clicked; this same click also opens task detail once through the host detail callback.
• Priority: hover state overrides selected state; when hover leaves, selected highlighting reappears.
• Dimming: when a chain is active, unrelated nodes and edges are dimmed.
• Neutral state: when nothing is hovered/selected, no highlight/dim classes are applied.
• Drag suppression: drag movements above the node drag threshold suppress the post-drag click, preventing accidental detail opens on pointer release.
• Edge rule: an edge is highlighted only when both its source and target nodes are in the active chain.

Controls

Toolbar (bottom-right)

• Zoom in (ZoomIn) — button + Ctrl+= / Cmd+=
• Zoom out (ZoomOut) — button + Ctrl+- / Cmd+-
• Zoom percent label — live readout (for example 100%, 75%, 250%)
• Fit to graph (Maximize) — button + Ctrl+Shift+F / Cmd+Shift+F
• Reset view (RotateCcw) — button + Ctrl+0 / Cmd+0

Additional keyboard behavior

• Escape resets to default view (zoom=1, pan=0,0)
• Shortcuts are suppressed when focus is inside input, textarea, select, or contentEditable elements

All controls are rendered as floating .btn-icon actions in the bottom-right corner, with mobile-friendly 44px touch targets in the @media (max-width: 768px) override.