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/*
* QR Code generator input demo (TypeScript)
*
* Copyright (c) Project Nayuki. (MIT License)
* https://www.nayuki.io/page/qr-code-generator-library
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
* - The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
* - The Software is provided "as is", without warranty of any kind, express or
* implied, including but not limited to the warranties of merchantability,
* fitness for a particular purpose and noninfringement. In no event shall the
* authors or copyright holders be liable for any claim, damages or other
* liability, whether in an action of contract, tort or otherwise, arising from,
* out of or in connection with the Software or the use or other dealings in the
* Software.
*/
"use strict";
namespace app {
function initialize(): void {
getElem("loading").style.display = "none";
getElem("loaded").style.removeProperty("display");
let elems = document.querySelectorAll("input[type=number], input[type=text], textarea");
for (let el of elems) {
if (el.id.indexOf("version-") != 0)
(el as any).oninput = redrawQrCode;
}
elems = document.querySelectorAll("input[type=radio], input[type=checkbox]");
for (let el of elems)
(el as HTMLInputElement).onchange = redrawQrCode;
redrawQrCode();
}
function redrawQrCode(): void {
// Show/hide rows based on bitmap/vector image output
const bitmapOutput: boolean = getInput("output-format-bitmap").checked;
const scaleRow : HTMLElement = getElem("scale-row");
const svgXmlRow: HTMLElement = getElem("svg-xml-row");
if (bitmapOutput) {
scaleRow.style.removeProperty("display");
svgXmlRow.style.display = "none";
} else {
scaleRow.style.display = "none";
svgXmlRow.style.removeProperty("display");
}
const svgXml = getElem("svg-xml-output") as HTMLTextAreaElement;
svgXml.value = "";
// Reset output images in case of early termination
const canvas = getElem("qrcode-canvas") as HTMLCanvasElement;
const svg = (document.getElementById("qrcode-svg") as Element) as SVGElement;
canvas.style.display = "none";
svg.style.display = "none";
// Returns a QrCode.Ecc object based on the radio buttons in the HTML form.
function getInputErrorCorrectionLevel(): qrcodegen.QrCode.Ecc {
if (getInput("errcorlvl-medium").checked)
return qrcodegen.QrCode.Ecc.MEDIUM;
else if (getInput("errcorlvl-quartile").checked)
return qrcodegen.QrCode.Ecc.QUARTILE;
else if (getInput("errcorlvl-high").checked)
return qrcodegen.QrCode.Ecc.HIGH;
else // In case no radio button is depressed
return qrcodegen.QrCode.Ecc.LOW;
}
// Get form inputs and compute QR Code
const ecl: qrcodegen.QrCode.Ecc = getInputErrorCorrectionLevel();
const text: string = (getElem("text-input") as HTMLTextAreaElement).value;
const segs: Array<qrcodegen.QrSegment> = qrcodegen.QrSegment.makeSegments(text);
const minVer: number = parseInt(getInput("version-min-input").value, 10);
const maxVer: number = parseInt(getInput("version-max-input").value, 10);
const mask: number = parseInt(getInput("mask-input").value, 10);
const boostEcc: boolean = getInput("boost-ecc-input").checked;
const qr: qrcodegen.QrCode = qrcodegen.QrCode.encodeSegments(segs, ecl, minVer, maxVer, mask, boostEcc);
// Draw image output
const border: number = parseInt(getInput("border-input").value, 10);
const lightColor: string = getInput("light-color-input").value;
const darkColor : string = getInput("dark-color-input" ).value;
if (border < 0 || border > 100)
return;
if (bitmapOutput) {
const scale: number = parseInt(getInput("scale-input").value, 10);
if (scale <= 0 || scale > 30)
return;
drawCanvas(qr, scale, border, lightColor, darkColor, canvas);
canvas.style.removeProperty("display");
} else {
const code: string = toSvgString(qr, border, lightColor, darkColor);
const viewBox: string = (/ viewBox="([^"]*)"/.exec(code) as RegExpExecArray)[1];
const pathD: string = (/ d="([^"]*)"/.exec(code) as RegExpExecArray)[1];
svg.setAttribute("viewBox", viewBox);
(svg.querySelector("path") as Element).setAttribute("d", pathD);
(svg.querySelector("rect") as Element).setAttribute("fill", lightColor);
(svg.querySelector("path") as Element).setAttribute("fill", darkColor);
svg.style.removeProperty("display");
svgXml.value = code;
}
// Returns a string to describe the given list of segments.
function describeSegments(segs: Array<qrcodegen.QrSegment>): string {
if (segs.length == 0)
return "none";
else if (segs.length == 1) {
const mode: qrcodegen.QrSegment.Mode = segs[0].mode;
const Mode = qrcodegen.QrSegment.Mode;
if (mode == Mode.NUMERIC ) return "numeric";
if (mode == Mode.ALPHANUMERIC) return "alphanumeric";
if (mode == Mode.BYTE ) return "byte";
if (mode == Mode.KANJI ) return "kanji";
return "unknown";
} else
return "multiple";
}
// Returns the number of Unicode code points in the given UTF-16 string.
function countUnicodeChars(str: string): number {
let result: number = 0;
for (let i = 0; i < str.length; i++, result++) {
const c: number = str.charCodeAt(i);
if (c < 0xD800 || c >= 0xE000)
continue;
else if (0xD800 <= c && c < 0xDC00 && i + 1 < str.length) { // High surrogate
i++;
const d: number = str.charCodeAt(i);
if (0xDC00 <= d && d < 0xE000) // Low surrogate
continue;
}
throw "Invalid UTF-16 string";
}
return result;
}
// Show the QR Code symbol's statistics as a string
getElem("statistics-output").textContent = `QR Code version = ${qr.version}, ` +
`mask pattern = ${qr.mask}, ` +
`character count = ${countUnicodeChars(text)},\n` +
`encoding mode = ${describeSegments(segs)}, ` +
`error correction = level ${"LMQH".charAt(qr.errorCorrectionLevel.ordinal)}, ` +
`data bits = ${qrcodegen.QrSegment.getTotalBits(segs, qr.version) as number}.`;
}
// Draws the given QR Code, with the given module scale and border modules, onto the given HTML
// canvas element. The canvas's width and height is resized to (qr.size + border * 2) * scale.
// The drawn image is purely dark and light, and fully opaque.
// The scale must be a positive integer and the border must be a non-negative integer.
function drawCanvas(qr: qrcodegen.QrCode, scale: number, border: number, lightColor: string, darkColor: string, canvas: HTMLCanvasElement): void {
if (scale <= 0 || border < 0)
throw "Value out of range";
const width: number = (qr.size + border * 2) * scale;
canvas.width = width;
canvas.height = width;
let ctx = canvas.getContext("2d") as CanvasRenderingContext2D;
for (let y = -border; y < qr.size + border; y++) {
for (let x = -border; x < qr.size + border; x++) {
ctx.fillStyle = qr.getModule(x, y) ? darkColor : lightColor;
ctx.fillRect((x + border) * scale, (y + border) * scale, scale, scale);
}
}
}
// Returns a string of SVG code for an image depicting the given QR Code, with the given number
// of border modules. The string always uses Unix newlines (\n), regardless of the platform.
function toSvgString(qr: qrcodegen.QrCode, border: number, lightColor: string, darkColor: string): string {
if (border < 0)
throw "Border must be non-negative";
let parts: Array<string> = [];
for (let y = 0; y < qr.size; y++) {
for (let x = 0; x < qr.size; x++) {
if (qr.getModule(x, y))
parts.push(`M${x + border},${y + border}h1v1h-1z`);
}
}
return `<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg xmlns="http://www.w3.org/2000/svg" version="1.1" viewBox="0 0 ${qr.size + border * 2} ${qr.size + border * 2}" stroke="none">
<rect width="100%" height="100%" fill="${lightColor}"/>
<path d="${parts.join(" ")}" fill="${darkColor}"/>
</svg>
`
}
export function handleVersionMinMax(which: "min"|"max"): void {
const minElem: HTMLInputElement = getInput("version-min-input");
const maxElem: HTMLInputElement = getInput("version-max-input");
let minVal: number = parseInt(minElem.value, 10);
let maxVal: number = parseInt(maxElem.value, 10);
minVal = Math.max(Math.min(minVal, qrcodegen.QrCode.MAX_VERSION), qrcodegen.QrCode.MIN_VERSION);
maxVal = Math.max(Math.min(maxVal, qrcodegen.QrCode.MAX_VERSION), qrcodegen.QrCode.MIN_VERSION);
if (which == "min" && minVal > maxVal)
maxVal = minVal;
else if (which == "max" && maxVal < minVal)
minVal = maxVal;
minElem.value = minVal.toString();
maxElem.value = maxVal.toString();
redrawQrCode();
}
function getElem(id: string): HTMLElement {
const result: HTMLElement|null = document.getElementById(id);
if (result instanceof HTMLElement)
return result;
throw "Assertion error";
}
function getInput(id: string): HTMLInputElement {
const result: HTMLElement = getElem(id);
if (result instanceof HTMLInputElement)
return result;
throw "Assertion error";
}
initialize();
}