Reference

#JavaScript API

Load bus-diagram.js to expose window.BusDiagram.

#Global functions

Function	Purpose
`version`	Version of the library, for example `"0.3.1"`; see versions.
`create(target, scenario?, options?)`	Create or reuse a `<bus-diagram>` at a selector or element; return the component.
`registerBehavior(id, definition)`	Register an extension behavior; duplicate IDs are rejected.
`registerEquipment(id, definition)`	Register an equipment model.
`registerEquipmentView(id, { size, render })`	Register an equipment drawing.
`buildScenario(json, registry?, t?)`	Validate and normalize JSON; raise `ScenarioError` with `{ path, code, message }` details on failure.
`toV2(scenario)`	Convert a normalized scenario to format-2 JSON.
`createSimulator(json, options?)`	Create a simulation without a DOM component.
`registerMessages(language, messages)`	Add or extend a locale catalog; see languages.
`availableLanguages()`	List available locale codes.
`translator(language)`	Get a translation function for validation and engine messages.
`html`, `svg`, `nothing`	Lit helpers for extension views.
`OPTION_DOCS`, `DEFAULT_OPTIONS`	Display-option metadata and defaults.

#`<bus-diagram>` element

#Attributes and properties

Name	Purpose
`scenario` attribute	Select a JSON `<script>` block by `#id`.
`src` attribute	Load a JSON file URL over HTTP.
`options` property	JavaScript display options, overriding attributes.
`view` property	Effective display options.
`simulation` property	Underlying simulation for advanced use.

#Methods

Method	Purpose
`load(json)`	Validate and replace the scenario, or display its errors.
`reset()`	Restore initial state and time zero.
`play()`, `pause()`	Resume or pause simulated time.
`advance(ms)`	Advance by a nonnegative number of simulated milliseconds, even while paused.
`stepToNextEvent()`	Advance to the next explanatory event; return `{ timeMs, events }` or `null`.
`setSpeed(n)`	Set a positive simulation speed.
`getState()`	Return a serializable copy of current state.
`on(name, handler)`	Subscribe to `telegram`, `ready`, or `error`; return an unsubscribe function.
`groupWrite(address, value, interface?)`	Write a group value through the scenario's USB interface.
`groupRead(address, interface?)`	Read a group value through the USB interface.
`roomAction(roomId, action, value)`	Set a room's window state or outside temperature.
`setClock(value)`	Set the simulated clock to a local date and time (`YYYY-MM-DDTHH:MM[:SS]`).

#`getState()` example

{
  "timeMs": 11639,
  "paused": false,
  "faulted": false,
  "objects": {
    "pushButton/feedback": {
      "value": 50.19607843137255,
      "updatedAtMs": 11939,
      "flags": { "W": true, "T": false, "R": false, "U": true }
    }
  },
  "channels": {
    "shutter/s1": {
      "output": { "type": "motor", "direction": "stop" },
      "state": { "estimatedPositionPct": 50.19607843137255, "phase": "idle" }
    }
  },
  "equipment": {
    "shutter/s1": {
      "type": "shutter",
      "state": { "positionPct": 33.46, "drive": "stop", "moving": false, "limit": null }
    }
  },
  "rooms": {
    "living": { "temperatureC": 20.8, "outsideTemperatureC": 5, "windowOpen": false }
  },
  "telegramsInFlight": 0,
  "diagnostics": []
}

The objects map uses deviceId/objectId identifiers. channels and equipment use deviceId/channelId; rooms uses room IDs. Unknown values are null.