feat(image-split): implement zip download and set filename

Adds a task to trigger the browser download of the generated ZIP file and replaces the placeholder filename with the original image's name.

Author: lilBunnyRabbit

src/routes/tools/image-split/index.lazy.tsx

@@ -91,7 +91,7 @@ function ImageSplitRoute(): React.ReactNode {
                   DownloadSplitCanvasTasks(
                     {
                       ...data,
-                      filename: "tralala",
+                      filename: imageFile.file.name,
                     },
                     imageFile
                   )

src/services/image-split/tasks/download-split-canvas/index.ts

@@ -18,5 +18,6 @@ export default function DownloadSplitCanvasTasks(config: DownloadSplitCanvasConf
     Tasks.CreateCanvas(),
     Tasks.CreateAndZip({ config, imageFile }),
     Tasks.PackageZip(),
+    Tasks.DownloadZip({ config }),
   ];
 }

src/services/image-split/tasks/download-split-canvas/task/downloadZip.task.ts

@@ -0,0 +1,53 @@
+import { createTask } from "@lilbunnyrabbit/task-manager";
+import { DownloadSplitCanvasConfig, DownloadSplitCanvasTask } from "..";
+
+export default createTask<{ config: DownloadSplitCanvasConfig }, string>({
+  name: "Download ZIP",
+
+  parse() {
+    switch (this.status) {
+      default:
+      case "idle": {
+        return {
+          status: "Download ZIP",
+        };
+      }
+      case "in-progress": {
+        return {
+          status: "Downloading...",
+        };
+      }
+      case "error": {
+        return {
+          status: "Failed to download...",
+        };
+      }
+      case "success": {
+        if (this.result.isPresent()) {
+          return {
+            status: "Downloaded",
+            result: this.result.get(),
+          };
+        }
+
+        return {
+          status: "No result.",
+        };
+      }
+    }
+  },
+
+  async execute({ config }) {
+    const blob = this.manager.getTaskResult(DownloadSplitCanvasTask.PackageZip);
+
+    const url = URL.createObjectURL(blob);
+    const a = document.createElement("a");
+    a.href = url;
+    a.download = `${config.filename}.zip`;
+    document.body.appendChild(a);
+    a.click();
+    document.body.removeChild(a);
+
+    return url;
+  },
+});

src/services/image-split/tasks/download-split-canvas/task/index.ts

@@ -1,5 +1,6 @@
 export { default as CreateAndZip } from "./createAndZip.task";
 export { default as CreateCanvas } from "./createCanvas.task";
 export { default as CreateZip } from "./createZip.task";
+export { default as DownloadZip } from "./downloadZip.task";
 export { default as GenerateInfo } from "./generateInfo.task";
 export { default as PackageZip } from "./packageZip.task";