Merge pull request #795 from thomasnordquist/tnordquist/decode-data-in-frontend

decode data in frontend

app/src/model/LegacyConnectionSettings.ts

@@ -1,5 +1,4 @@
 import { ConnectionOptions, createEmptyConnection } from './ConnectionOptions'
-import { v4 } from 'uuid'
 
 interface LegacyConnectionSettings {
   host: string

app/src/model/TopicViewModel.ts

@@ -1,19 +1,77 @@
+import * as q from '../../../backend/src/Model'
 import { Destroyable } from '../../../backend/src/Model/Destroyable'
+import { MessageDecoder, decoders } from '../decoders'
 import { EventDispatcher } from '../../../events'
 
+function findDecoder<T extends Destroyable>(node: q.TreeNode<T>): TopicDecoder | undefined {
+  const decoder = decoders.find(
+    decoder =>
+      decoder.canDecodeTopic?.(node.path()) || (node.message?.payload && decoder.canDecodeData?.(node.message?.payload))
+  )
+
+  return decoder
+    ? {
+        decoder,
+        format: undefined,
+      }
+    : undefined
+}
+
+type TopicDecoder = { decoder: MessageDecoder; format: string | undefined }
+
 export class TopicViewModel implements Destroyable {
   private selected: boolean
   private expanded: boolean
+  private owner: q.TreeNode<TopicViewModel> | undefined
+  private _decoder?: TopicDecoder
+  /**
+   * Reference counter for useViewModel hook
+   */
+  private referenceCounter = 0
   public selectionChange = new EventDispatcher<void>()
   public expandedChange = new EventDispatcher<void>()
+  public onDecoderChange = new EventDispatcher<TopicDecoder | undefined>()
 
-  public constructor() {
+  get decoder(): TopicDecoder | undefined {
+    if (!this._decoder) {
+      this._decoder = this.owner && findDecoder(this.owner)
+    }
+
+    return this._decoder
+  }
+
+  set decoder(override: TopicDecoder | undefined) {
+    this._decoder = override
+
+    this.onDecoderChange.dispatch(override)
+  }
+
+  public constructor(treeNode: q.TreeNode<TopicViewModel>) {
+    this.owner = treeNode
     this.selected = false
     this.expanded = false
   }
 
+  public retain() {
+    this.referenceCounter += 1
+  }
+
+  public release() {
+    this.referenceCounter -= 1
+    if (this.referenceCounter <= 0) {
+      this.destroy()
+    }
+  }
+
   public destroy() {
+    console.log('destroy', this.referenceCounter)
+    if (this.owner) {
+      this.owner.viewModel = undefined
+      this.owner = undefined
+    }
     this.selectionChange.removeAllListeners()
+    this.onDecoderChange.removeAllListeners()
+    this.expandedChange.removeAllListeners()
   }
 
   public isSelected() {