Add generation engine and signals

frontend/realtime/src/KonvaApp/GenerationEngine.ts

@@ -0,0 +1,45 @@
+import { invoke } from "@tauri-apps/api/core";
+import {
+  cancelGeneration,
+  finishGeneration,
+  onStartGeneration,
+} from "~/signals/generation/generationSignals";
+
+export class GenerationEngine {
+  private isGenerating = false;
+
+  constructor() {
+    this.attachEventListeners();
+  }
+
+  private attachEventListeners() {
+    onStartGeneration((prompt) => {
+      this.invokeGeneration(prompt);
+    });
+  }
+
+  private async invokeGeneration(prompt: string) {
+    if (this.isGenerating) {
+      return;
+    }
+
+    this.isGenerating = true;
+    console.log("Invoking generation for prompt:", prompt);
+
+    try {
+      const base64BitmapResponse = await invoke("infer_image", {
+        prompt: prompt,
+      });
+
+      console.log("Generation finished with response:", base64BitmapResponse);
+
+      const base64string = base64BitmapResponse as string;
+      finishGeneration(base64string);
+    } catch (error) {
+      console.error("Error during image processing:", error);
+      cancelGeneration();
+    } finally {
+      this.isGenerating = false;
+    }
+  }
+}

frontend/realtime/src/signals/generation/generationSignals.ts

@@ -1,4 +1,4 @@
-import { signal } from "@preact/signals-react";
+import { effect, signal } from "@preact/signals-react";
 
 export enum GenerationLoadingState {
   INIT,
@@ -6,8 +6,45 @@ export enum GenerationLoadingState {
   GENERATED,
 }
 
+const initValue = { loadingState: GenerationLoadingState.INIT, prompt: "" };
+
 export const generationSignal = signal<{
-    loadingState: GenerationLoadingState;
-    prompt: string;
+  loadingState: GenerationLoadingState;
+  prompt: string;
   imageB64?: string;
-}>({ loadingState: GenerationLoadingState.INIT, prompt: "" });
+}>(initValue);
+
+export const startGeneration = (prompt: string) => {
+  generationSignal.value = {
+    loadingState: GenerationLoadingState.GENERATING,
+    prompt,
+    imageB64: undefined,
+  };
+};
+
+export const onStartGeneration = (callback: (prompt: string) => void) => {
+  effect(() => {
+    // If value just changed to GENERATING, notify the listeners
+    if (
+      generationSignal.value.loadingState === GenerationLoadingState.GENERATING
+    ) {
+      callback(generationSignal.value.prompt);
+    }
+  });
+};
+
+export const finishGeneration = (imageB64: string) => {
+  generationSignal.value = {
+    loadingState: GenerationLoadingState.GENERATED,
+    prompt: generationSignal.value.prompt,
+    imageB64,
+  };
+};
+
+export const cancelGeneration = () => {
+  if (
+    generationSignal.value.loadingState === GenerationLoadingState.GENERATING
+  ) {
+    generationSignal.value = initValue;
+  }
+};