tldraw_0/state/sessions/edit-session.ts

import { Data, LineShape, RayShape, Shape } from 'types'
import vec from 'utils/vec'
import BaseSession from './base-session'
import commands from 'state/commands'
import { current } from 'immer'
import {
  getPage,
  getPageState,
  getSelectedIds,
  getSelectedShapes,
  getShape,
} from 'utils/utils'
import { getShapeUtils } from 'lib/shape-utils'

export default class EditSession extends BaseSession {
  snapshot: EditSnapshot

  constructor(data: Data) {
    super(data)
    this.snapshot = getEditSnapshot(data)
  }

  update(data: Data, change: Partial<Shape>) {
    const initialShape = this.snapshot.initialShape
    const shape = getShape(data, initialShape.id)
    const utils = getShapeUtils(shape)
    Object.entries(change).forEach(([key, value]) => {
      utils.setProperty(shape, key as keyof Shape, value as Shape[keyof Shape])
    })
  }

  cancel(data: Data) {
    const initialShape = this.snapshot.initialShape
    const page = getPage(data)
    page.shapes[initialShape.id] = initialShape
  }

  complete(data: Data) {
    commands.edit(data, this.snapshot, getEditSnapshot(data))
  }
}

export function getEditSnapshot(data: Data) {
  const initialShape = getSelectedShapes(current(data))[0]

  return {
    currentPageId: data.currentPageId,
    initialShape,
  }
}

export type EditSnapshot = ReturnType<typeof getEditSnapshot>