persist and restore window state

.vscode/launch.json

@@ -0,0 +1,18 @@
+{
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "name": "Debug Main Process",
+      "type": "node",
+      "request": "launch",
+      "cwd": "${workspaceRoot}/build",
+      "runtimeExecutable": "${workspaceRoot}/node_modules/.bin/electron",
+      "windows": {
+        "runtimeExecutable": "${workspaceRoot}/node_modules/.bin/electron.cmd"
+      },
+      "args": [
+        "."
+      ]
+    }
+  ]
+}

package.json

@@ -22,7 +22,7 @@
     "build:main": "webpack --config webpack.main.js",
     "build:renderer": "webpack --config webpack.renderer.js",
     "build:renderer:watch": "webpack --config webpack.renderer.js --watch",
-    "electron": "npm run build:main && (electron ./build --watch | npm run build:renderer:watch)",
+    "electron": "npm run build:main && (electron --inspect=5858 ./build --watch | npm run build:renderer:watch)",
     "pack": "electron-builder --dir",
     "dist": "electron-builder"
   },

src/main/window.main.ts

@@ -5,9 +5,17 @@ import * as url from 'url';
 import { Main } from '../main';
 import { isDev } from '../scripts/utils';
 
+const WindowEventHandlingDelay = 100;
+const Keys = {
+    mainWindowSize: 'mainWindowSize',
+};
+
 export class WindowMain {
     win: BrowserWindow;
 
+    private windowStateChangeTimer: NodeJS.Timer;
+    private windowStates: { [key: string]: any; } = {};
+
     constructor(private main: Main) { }
 
     init(): Promise<any> {
@@ -16,8 +24,8 @@ export class WindowMain {
                 // This method will be called when Electron has finished
                 // initialization and is ready to create browser windows.
                 // Some APIs can only be used after this event occurs.
-                app.on('ready', () => {
-                    this.createWindow();
+                app.on('ready', async () => {
+                    await this.createWindow();
                     resolve();
                 });
 
@@ -30,11 +38,11 @@ export class WindowMain {
                     }
                 });
 
-                app.on('activate', () => {
+                app.on('activate', async () => {
                     // On OS X it's common to re-create a window in the app when the
                     // dock icon is clicked and there are no other windows open.
                     if (this.win === null) {
-                        this.createWindow();
+                        await this.createWindow();
                     }
                 });
 
@@ -46,20 +54,30 @@ export class WindowMain {
         });
     }
 
-    private createWindow() {
-        const primaryScreenSize = screen.getPrimaryDisplay().workAreaSize;
+    private async createWindow() {
+        this.windowStates[Keys.mainWindowSize] = await this.getWindowState(Keys.mainWindowSize, 950, 600);
 
         // Create the browser window.
         this.win = new BrowserWindow({
-            width: primaryScreenSize.width < 950 ? primaryScreenSize.width : 950,
-            height: primaryScreenSize.height < 600 ? primaryScreenSize.height : 600,
+            width: this.windowStates[Keys.mainWindowSize].width,
+            height: this.windowStates[Keys.mainWindowSize].height,
             minWidth: 680,
             minHeight: 500,
+            x: this.windowStates[Keys.mainWindowSize].x,
+            y: this.windowStates[Keys.mainWindowSize].y,
             title: app.getName(),
             darkTheme: true,
             vibrancy: 'ultra-dark',
+            show: false,
         });
 
+        if (this.windowStates[Keys.mainWindowSize].isMaximized) {
+            this.win.maximize();
+        }
+
+        // Show it later since it might need to be maximized.
+        this.win.show();
+
         // and load the index.html of the app.
         this.win.loadURL(url.format({
             protocol: 'file:',
@@ -73,11 +91,110 @@ export class WindowMain {
         }
 
         // Emitted when the window is closed.
-        this.win.on('closed', () => {
+        this.win.on('closed', async () => {
+            await this.updateWindowState(Keys.mainWindowSize, this.win);
+
             // Dereference the window object, usually you would store window
             // in an array if your app supports multi windows, this is the time
             // when you should delete the corresponding element.
             this.win = null;
         });
+
+        this.win.on('close', async () => {
+            await this.updateWindowState(Keys.mainWindowSize, this.win);
+        });
+
+        this.win.on('maximize', async () => {
+            await this.updateWindowState(Keys.mainWindowSize, this.win);
+        });
+
+        this.win.on('unmaximize', async () => {
+            await this.updateWindowState(Keys.mainWindowSize, this.win);
+        });
+
+        this.win.on('resize', () => {
+            this.windowStateChangeHandler(Keys.mainWindowSize, this.win);
+        });
+
+        this.win.on('move', () => {
+            this.windowStateChangeHandler(Keys.mainWindowSize, this.win);
+        });
+    }
+
+    private windowStateChangeHandler(configKey: string, win: BrowserWindow) {
+        global.clearTimeout(this.windowStateChangeTimer);
+        this.windowStateChangeTimer = setTimeout(async () => {
+            await this.updateWindowState(configKey, win);
+        }, WindowEventHandlingDelay);
+    }
+
+    private async updateWindowState(configKey: string, win: BrowserWindow) {
+        if (win == null) {
+            return;
+        }
+
+        try {
+            const bounds = win.getBounds();
+
+            if (this.windowStates[configKey] == null) {
+                this.windowStates[configKey] = await this.main.storageService.get<any>(configKey);
+                if (this.windowStates[configKey] == null) {
+                    this.windowStates[configKey] = {};
+                }
+            }
+
+            this.windowStates[configKey].isMaximized = win.isMaximized();
+            this.windowStates[configKey].displayBounds = screen.getDisplayMatching(bounds).bounds;
+
+            if (!win.isMaximized() && !win.isMinimized() && !win.isFullScreen()) {
+                this.windowStates[configKey].x = bounds.x;
+                this.windowStates[configKey].y = bounds.y;
+                this.windowStates[configKey].width = bounds.width;
+                this.windowStates[configKey].height = bounds.height;
+            }
+
+            await this.main.storageService.save(configKey, this.windowStates[configKey]);
+        } catch (e) { }
+    }
+
+    private async getWindowState(configKey: string, defaultWidth: number, defaultHeight: number) {
+        let state = await this.main.storageService.get<any>(configKey);
+
+        const isValid = state != null && (this.stateHasBounds(state) || state.isMaximized);
+        let displayBounds: Electron.Rectangle = null;
+        if (!isValid) {
+            state = {
+                width: defaultWidth,
+                height: defaultHeight,
+            };
+
+            displayBounds = screen.getPrimaryDisplay().bounds;
+        } else if (this.stateHasBounds(state) && state.displayBounds) {
+            // Check if the display where the window was last open is still available
+            displayBounds = screen.getDisplayMatching(state.displayBounds).bounds;
+
+            if (displayBounds.width !== state.displayBounds.width ||
+                displayBounds.height !== state.displayBounds.height ||
+                displayBounds.x !== state.displayBounds.x ||
+                displayBounds.y !== state.displayBounds.y) {
+                state.x = undefined;
+                state.y = undefined;
+                displayBounds = screen.getPrimaryDisplay().bounds;
+            }
+        }
+
+        if (state.width > displayBounds.width) {
+            state.width = displayBounds.width;
+        }
+        if (state.height > displayBounds.height) {
+            state.height = displayBounds.height;
+        }
+
+        return state;
+    }
+
+    private stateHasBounds(state: any): boolean {
+        return state != null && Number.isInteger(state.x) && Number.isInteger(state.y) &&
+            Number.isInteger(state.width) && state.width > 0 && Number.isInteger(state.height) && state.height > 0;
     }
 }