diff src/app/analysis-item/AnalysisItem.ts @ 460:ccce2c09502e

Manually cherry-pick various refactoring efforts from feature/basic-session-loading

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/app/analysis-item/AnalysisItem.ts	Fri Jun 30 10:41:30 2017 +0100
@@ -0,0 +1,82 @@
+/**
+ * Created by lucast on 08/06/2017.
+ */
+import {KnownShapedFeature} from '../visualisations/FeatureUtilities';
+import {SimpleRequest} from 'piper/HigherLevelUtilities';
+export abstract class Item {
+  id: string;
+  hasSharedTimeline: boolean;
+  title?: string;
+  description?: string;
+  progress?: number;
+}
+
+export interface RootAudioItem extends Item {
+  uri: string;
+  mimeType?: string;
+  isExportable?: boolean;
+}
+export interface LoadedRootAudioItem extends RootAudioItem {
+  audioData: AudioBuffer;
+}
+
+export interface AnalysisItem extends Item {
+  parent: LoadedRootAudioItem;
+  extractorKey: string;
+  outputId: string;
+}
+
+export type ExtractedAnalysisItem = AnalysisItem & KnownShapedFeature & {
+  unit?: string
+};
+
+export function isItem(item: Item): item is Item {
+  return item.id != null && item.hasSharedTimeline != null;
+}
+
+export function isPendingRootAudioItem(item: Item): item is RootAudioItem {
+  return isItem(item) && typeof (item as RootAudioItem).uri === 'string';
+}
+
+export function isLoadedRootAudioItem(item: Item): item is LoadedRootAudioItem {
+  return item && isPendingRootAudioItem(item) &&
+    (item as LoadedRootAudioItem).audioData instanceof AudioBuffer;
+}
+
+export function isPendingAnalysisItem(item: Item): item is AnalysisItem {
+  const downcast = (item as ExtractedAnalysisItem);
+  return isLoadedRootAudioItem(downcast.parent)
+    && typeof downcast.extractorKey === 'string';
+}
+
+export function isExtractedAnalysisItem(it: Item): it is ExtractedAnalysisItem {
+  const downcast = (it as ExtractedAnalysisItem);
+  return isPendingAnalysisItem(it) &&
+    downcast.shape != null &&
+    downcast.collected != null;
+}
+
+// these should probably be actual concrete types with their own getUri methods
+export function getRootUri(item: Item): string {
+  if (isPendingRootAudioItem(item)) {
+    return item.uri;
+  }
+  if (isPendingAnalysisItem(item)) {
+    return item.parent.uri;
+  }
+  throw new Error('Invalid item: No URI property set.');
+}
+
+export function createExtractionRequest(item: AnalysisItem): SimpleRequest {
+  return {
+    audioData: [...Array(item.parent.audioData.numberOfChannels).keys()]
+      .map(i => item.parent.audioData.getChannelData(i)),
+    audioFormat: {
+      sampleRate: item.parent.audioData.sampleRate,
+      channelCount: item.parent.audioData.numberOfChannels,
+      length: item.parent.audioData.length
+    },
+    key: item.extractorKey,
+    outputId: item.outputId
+  };
+}