feat(core): update session, security system and QR exchange

- Removed session creation and Lightning payment logic
- Refactored security system:
  * no more restrictions
  * all systems enabled on session creation
- Improved QR code exchange for mobile devices

node_modules/html5-qrcode/src/ui/scanner/file-selection-ui.ts

@@ -0,0 +1,263 @@
+/**
+ * @fileoverview
+ * File for file selection UI handling.
+ * 
+ * @author mebjas <minhazav@gmail.com>
+ * 
+ * The word "QR Code" is registered trademark of DENSO WAVE INCORPORATED
+ * http://www.denso-wave.com/qrcode/faqpatent-e.html
+ */
+
+import {Html5QrcodeScannerStrings} from "../../strings";
+import {
+    BaseUiElementFactory,
+    PublicUiElementIdAndClasses
+} from "./base";
+
+/**
+ * Interface for callback when a file is selected by user using the button.
+ */
+export type OnFileSelected = (file: File) => void;
+
+/** UI class for file selection handling. */
+export class FileSelectionUi {
+
+    private readonly fileBasedScanRegion: HTMLDivElement;
+    private readonly fileScanInput: HTMLInputElement;
+    private readonly fileSelectionButton: HTMLButtonElement;
+
+    /** Creates object and renders. */
+    private constructor(
+        parentElement: HTMLDivElement,
+        showOnRender: boolean,
+        onFileSelected: OnFileSelected) {
+        this.fileBasedScanRegion = this.createFileBasedScanRegion();
+        this.fileBasedScanRegion.style.display
+            = showOnRender ? "block" : "none";
+        parentElement.appendChild(this.fileBasedScanRegion);
+
+        let fileScanLabel = document.createElement("label");
+        fileScanLabel.setAttribute("for", this.getFileScanInputId());
+        fileScanLabel.style.display = "inline-block";
+
+        this.fileBasedScanRegion.appendChild(fileScanLabel);
+        
+        this.fileSelectionButton
+            = BaseUiElementFactory.createElement<HTMLButtonElement>(
+                "button",
+                PublicUiElementIdAndClasses.FILE_SELECTION_BUTTON_ID);
+        this.setInitialValueToButton();
+
+        // Bind click events with the label element.
+        this.fileSelectionButton.addEventListener("click", (_) => {
+            fileScanLabel.click();
+        });
+        fileScanLabel.append(this.fileSelectionButton);
+
+        this.fileScanInput
+            = BaseUiElementFactory.createElement<HTMLInputElement>(
+                "input", this.getFileScanInputId());
+        this.fileScanInput.type = "file";
+        this.fileScanInput.accept = "image/*";
+        this.fileScanInput.style.display = "none";
+        fileScanLabel.appendChild(this.fileScanInput);
+        
+        let $this = this;
+        /*eslint complexity: ["error", 5]*/
+        this.fileScanInput.addEventListener("change", (e: Event) => {
+            if (e == null || e.target == null) {
+                return;
+            }
+            let target: HTMLInputElement = e.target as HTMLInputElement;
+            if (target.files && target.files.length === 0) {
+                return;
+            }
+            let fileList: FileList = target.files!;
+            const file: File = fileList[0];
+            let fileName = file.name;
+            $this.setImageNameToButton(fileName);
+
+            onFileSelected(file);
+        });
+
+        // Render drag and drop label
+        let dragAndDropMessage = this.createDragAndDropMessage();
+        this.fileBasedScanRegion.appendChild(dragAndDropMessage);
+
+        this.fileBasedScanRegion.addEventListener("dragenter", function(event) {
+            $this.fileBasedScanRegion.style.border
+                = $this.fileBasedScanRegionActiveBorder();
+
+            event.stopPropagation();
+            event.preventDefault();
+        });
+
+        this.fileBasedScanRegion.addEventListener("dragleave", function(event) {
+            $this.fileBasedScanRegion.style.border
+                = $this.fileBasedScanRegionDefaultBorder();
+
+            event.stopPropagation();
+            event.preventDefault();
+        });
+
+        this.fileBasedScanRegion.addEventListener("dragover", function(event) {
+            $this.fileBasedScanRegion.style.border
+                = $this.fileBasedScanRegionActiveBorder();
+
+            event.stopPropagation();
+            event.preventDefault();
+        });
+
+        /*eslint complexity: ["error", 10]*/
+        this.fileBasedScanRegion.addEventListener("drop", function(event) {
+            event.stopPropagation();
+            event.preventDefault();
+
+            $this.fileBasedScanRegion.style.border
+                = $this.fileBasedScanRegionDefaultBorder();
+
+            var dataTransfer = event.dataTransfer;
+            if (dataTransfer) {
+                let files = dataTransfer.files;
+                if (!files || files.length === 0) {
+                    return;
+                }
+                let isAnyFileImage = false;
+                for (let i = 0; i < files.length; ++i) {
+                    let file = files.item(i);
+                    if (!file) {
+                        continue;
+                    }
+                    let imageType = /image.*/;
+
+                    // Only process images.
+                    if (!file.type.match(imageType)) {
+                        continue;
+                    }
+
+                    isAnyFileImage = true;
+                    let fileName = file.name;
+                    $this.setImageNameToButton(fileName);
+
+                    onFileSelected(file);
+                    dragAndDropMessage.innerText
+                        = Html5QrcodeScannerStrings.dragAndDropMessage();
+                    break;
+                }
+                
+                // None of the files were images.
+                if (!isAnyFileImage) {
+                    dragAndDropMessage.innerText
+                        = Html5QrcodeScannerStrings
+                            .dragAndDropMessageOnlyImages();
+                }
+            }
+
+        });
+    }
+
+    //#region Public APIs.
+    /** Hide the file selection UI. */
+    public hide() {
+        this.fileBasedScanRegion.style.display = "none";
+        this.fileScanInput.disabled = true;
+    }
+
+    /** Show the file selection UI. */
+    public show() {
+        this.fileBasedScanRegion.style.display = "block";
+        this.fileScanInput.disabled = false;
+    }
+
+    /** Returns {@code true} if UI container is displayed. */
+    public isShowing(): boolean {
+        return this.fileBasedScanRegion.style.display === "block";
+    }
+
+    /** Reset the file selection value */
+    public resetValue() {
+        this.fileScanInput.value = "";
+        this.setInitialValueToButton();
+    }
+    //#endregion
+
+    //#region private APIs
+    private createFileBasedScanRegion(): HTMLDivElement {
+        let fileBasedScanRegion = document.createElement("div");
+        fileBasedScanRegion.style.textAlign = "center";
+        fileBasedScanRegion.style.margin = "auto";
+        fileBasedScanRegion.style.width = "80%";
+        fileBasedScanRegion.style.maxWidth = "600px";
+        fileBasedScanRegion.style.border
+            = this.fileBasedScanRegionDefaultBorder();
+        fileBasedScanRegion.style.padding = "10px";
+        fileBasedScanRegion.style.marginBottom = "10px";
+        return fileBasedScanRegion;
+    }
+
+    private fileBasedScanRegionDefaultBorder() {
+        return "6px dashed #ebebeb";
+    }
+
+    /** Border when a file is being dragged over the file scan region. */
+    private fileBasedScanRegionActiveBorder() {
+        return "6px dashed rgb(153 151 151)";
+    }
+
+    private createDragAndDropMessage(): HTMLDivElement {
+        let dragAndDropMessage = document.createElement("div");
+        dragAndDropMessage.innerText
+            = Html5QrcodeScannerStrings.dragAndDropMessage();
+        dragAndDropMessage.style.fontWeight = "400";
+        return dragAndDropMessage;
+    }
+
+    private setImageNameToButton(imageFileName: string) {
+        const MAX_CHARS = 20;
+        if (imageFileName.length > MAX_CHARS) {
+            // Strip first 8
+            // Strip last 8
+            // Add 4 dots
+            let start8Chars = imageFileName.substring(0, 8);
+            let length = imageFileName.length;
+            let last8Chars = imageFileName.substring(length - 8, length);
+            imageFileName = `${start8Chars}....${last8Chars}`;
+        }
+
+        let newText = Html5QrcodeScannerStrings.fileSelectionChooseAnother()
+            + " - "
+            + imageFileName;
+        this.fileSelectionButton.innerText = newText;
+    }
+
+    private setInitialValueToButton() {
+        let initialText = Html5QrcodeScannerStrings.fileSelectionChooseImage()
+            + " - "
+            + Html5QrcodeScannerStrings.fileSelectionNoImageSelected();
+        this.fileSelectionButton.innerText = initialText;
+    }
+
+    private getFileScanInputId(): string {
+        return "html5-qrcode-private-filescan-input";
+    }
+    //#endregion
+
+    /**
+     * Creates a file selection UI and renders.
+     * 
+     * @param parentElement parent div element to render the UI to.
+     * @param showOnRender if {@code true}, the UI will be shown upon render
+     *  else hidden.
+     * @param onFileSelected callback to be called when file selection changes.
+     * 
+     * @returns Instance of {@code FileSelectionUi}.
+     */
+    public static create(
+        parentElement: HTMLDivElement,
+        showOnRender: boolean,
+        onFileSelected: OnFileSelected): FileSelectionUi {
+        let button = new FileSelectionUi(
+            parentElement, showOnRender, onFileSelected);
+        return button;
+    }
+}