Move screenshot functions to a separate file

src/utils/screenshot.ts

@@ -0,0 +1,72 @@
+import { AppInterface, STATES } from "./global";
+import { CE } from "./html";
+
+
+export class Screenshot {
+    static #filters: string = '';
+
+    static setup() {
+        const currentStream = STATES.currentStream;
+        if (!currentStream.$screenshotCanvas) {
+            currentStream.$screenshotCanvas = CE<HTMLCanvasElement>('canvas', {'class': 'bx-gone'});
+        }
+        // document.documentElement.appendChild(currentStream.$screenshotCanvas!);
+    }
+
+    static updateCanvasSize(width: number, height: number) {
+        const $canvas = STATES.currentStream.$screenshotCanvas;
+        if ($canvas) {
+            $canvas.width = width;
+            $canvas.height = height;
+        }
+    }
+
+    static updateCanvasFilters(filters: string) {
+        Screenshot.#filters = filters;
+    }
+
+    static takeScreenshot(callback?: any) {
+        const currentStream = STATES.currentStream;
+        const $video = currentStream.$video;
+        const $canvas = currentStream.$screenshotCanvas;
+        if (!$video || !$canvas) {
+            return;
+        }
+
+        const canvasContext = $canvas.getContext('2d', {
+                alpha: false,
+                willReadFrequently: false,
+            })!;
+
+        canvasContext.filter = Screenshot.#filters;
+        canvasContext.drawImage($video, 0, 0, $canvas.width, $canvas.height);
+
+        // Get data URL and pass to parent app
+        if (AppInterface) {
+            const data = $canvas.toDataURL('image/png').split(';base64,')[1];
+            AppInterface.saveScreenshot(currentStream.titleId, data);
+
+            // Free screenshot from memory
+            canvasContext.clearRect(0, 0, $canvas.width, $canvas.height);
+
+            callback && callback();
+            return;
+        }
+
+        $canvas && $canvas.toBlob(blob => {
+                // Download screenshot
+                const now = +new Date;
+                const $anchor = CE<HTMLAnchorElement>('a', {
+                        'download': `${currentStream.titleId}-${now}.png`,
+                        'href': URL.createObjectURL(blob!),
+                    });
+                $anchor.click();
+
+                // Free screenshot from memory
+                URL.revokeObjectURL($anchor.href);
+                canvasContext.clearRect(0, 0, $canvas.width, $canvas.height);
+
+                callback && callback();
+            }, 'image/png');
+    }
+}