Feat: save waveform as file (#118)

* package rpm

* cache waveform data as file in library

* clear waveform data in db

* fix some css

enjoy/src/main/waveform.ts

@@ -0,0 +1,38 @@
+import { ipcMain } from "electron";
+import settings from "@main/settings";
+import path from "path";
+import fs from "fs-extra";
+
+export class Waveform {
+  public dir = path.join(settings.libraryPath(), "waveforms");
+
+  constructor() {
+    fs.ensureDirSync(this.dir);
+  }
+
+  find(id: string) {
+    const file = path.join(this.dir, id + ".waveform.json");
+
+    if (fs.existsSync(file)) {
+      return fs.readJsonSync(file);
+    } else {
+      return null;
+    }
+  }
+
+  save(id: string, data: WaveFormDataType) {
+    const file = path.join(this.dir, id + ".waveform.json");
+
+    fs.writeJsonSync(file, data);
+  }
+
+  registerIpcHandlers() {
+    ipcMain.handle("waveforms-find", async (_event, id) => {
+      return this.find(id);
+    });
+
+    ipcMain.handle("waveforms-save", (_event, id, data) => {
+      return this.save(id, data);
+    });
+  }
+}