BugFix: fix perceivedLatency being calculated incorrectly

The perceivedLatency is currently calculateand and sent when we send
STE, by then lastUserModificationTime is no longer accurate.
Instead calculate perceivedLatency when we show the suggestions and use
the lastUserModificationTime at that time to be accurate.

Author: andrewyuq

packages/core/src/codewhisperer/service/inlineCompletionItemProvider.ts

@@ -12,6 +12,7 @@ import { ReferenceInlineProvider } from './referenceInlineProvider'
 import { ImportAdderProvider } from './importAdderProvider'
 import { application } from '../util/codeWhispererApplication'
 import path from 'path'
+import { vsCodeState } from '../indexNode'
 
 export class CWInlineCompletionItemProvider implements vscode.InlineCompletionItemProvider {
     private activeItemIndex: number | undefined
@@ -169,6 +170,7 @@ export class CWInlineCompletionItemProvider implements vscode.InlineCompletionIt
             ImportAdderProvider.instance.onShowRecommendation(document, this.startPos.line, r)
             this.nextMove = 0
             TelemetryHelper.instance.setFirstSuggestionShowTime()
+            session.setPerceivedLatency()
             this._onDidShow.fire()
             if (matchedCount >= 2 || this.nextToken !== '') {
                 const result = [item]

packages/core/src/codewhisperer/util/codeWhispererSession.ts

@@ -13,6 +13,7 @@ import {
 import { GenerateRecommendationsRequest, ListRecommendationsRequest, Recommendation } from '../client/codewhisperer'
 import { Position } from 'vscode'
 import { CodeWhispererSupplementalContext, vsCodeState } from '../models/model'
+import { resolveTransitionHooks } from 'vue'
 
 class CodeWhispererSession {
     static #instance: CodeWhispererSession
@@ -43,6 +44,7 @@ class CodeWhispererSession {
     invokeSuggestionStartTime = 0
     timeToFirstRecommendation = 0
     firstSuggestionShowTime = 0
+    perceivedLatency = 0
 
     public static get instance() {
         return (this.#instance ??= new CodeWhispererSession())
@@ -91,6 +93,17 @@ class CodeWhispererSession {
         }
     }
 
+    setPerceivedLatency() {
+        if (this.perceivedLatency !== 0) {
+            return
+        }
+        if (this.triggerType === 'OnDemand') {
+            this.perceivedLatency = this.timeToFirstRecommendation
+        } else {
+            this.perceivedLatency = this.firstSuggestionShowTime - vsCodeState.lastUserModificationTime
+        }
+    }
+
     reset() {
         this.sessionId = ''
         this.requestContext = { request: {} as any, supplementalMetadata: {} as any }

packages/core/src/codewhisperer/util/telemetryHelper.ts

@@ -325,9 +325,7 @@ export class TelemetryHelper {
                         suggestionState: this.getSendTelemetrySuggestionState(aggregatedSuggestionState),
                         recommendationLatencyMilliseconds: e2eLatency,
                         triggerToResponseLatencyMilliseconds: session.timeToFirstRecommendation,
-                        perceivedLatencyMilliseconds: session.getPerceivedLatency(
-                            this.sessionDecisions[0].codewhispererTriggerType
-                        ),
+                        perceivedLatencyMilliseconds: session.perceivedLatency,
                         timestamp: new Date(Date.now()),
                         suggestionReferenceCount: referenceCount,
                         generatedLine: generatedLines,
@@ -388,6 +386,7 @@ export class TelemetryHelper {
         this.typeAheadLength = 0
         this.timeSinceLastModification = 0
         session.timeToFirstRecommendation = 0
+        session.perceivedLatency = 0
         this.classifierResult = undefined
         this.classifierThreshold = undefined
     }