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1/*
2 * QR Code generator input demo (TypeScript)
3 *
4 * Copyright (c) Project Nayuki. (MIT License)
5 * https://www.nayuki.io/page/qr-code-generator-library
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a copy of
8 * this software and associated documentation files (the "Software"), to deal in
9 * the Software without restriction, including without limitation the rights to
10 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
11 * the Software, and to permit persons to whom the Software is furnished to do so,
12 * subject to the following conditions:
13 * - The above copyright notice and this permission notice shall be included in
14 *   all copies or substantial portions of the Software.
15 * - The Software is provided "as is", without warranty of any kind, express or
16 *   implied, including but not limited to the warranties of merchantability,
17 *   fitness for a particular purpose and noninfringement. In no event shall the
18 *   authors or copyright holders be liable for any claim, damages or other
19 *   liability, whether in an action of contract, tort or otherwise, arising from,
20 *   out of or in connection with the Software or the use or other dealings in the
21 *   Software.
22 */
23
24"use strict";
25
26
27namespace app {
28
29	function initialize(): void {
30		getElem("loading").style.display = "none";
31		getElem("loaded").style.removeProperty("display");
32		let elems = document.querySelectorAll("input[type=number], textarea");
33		for (let el of elems) {
34			if (el.id.indexOf("version-") != 0)
35				(el as any).oninput = redrawQrCode;
36		}
37		elems = document.querySelectorAll("input[type=radio], input[type=checkbox]");
38		for (let el of elems)
39			(el as HTMLInputElement).onchange = redrawQrCode;
40		redrawQrCode();
41	}
42
43
44	function redrawQrCode(): void {
45		// Show/hide rows based on bitmap/vector image output
46		const bitmapOutput: boolean = getInput("output-format-bitmap").checked;
47		const scaleRow : HTMLElement = getElem("scale-row");
48		const svgXmlRow: HTMLElement = getElem("svg-xml-row");
49		if (bitmapOutput) {
50			scaleRow.style.removeProperty("display");
51			svgXmlRow.style.display = "none";
52		} else {
53			scaleRow.style.display = "none";
54			svgXmlRow.style.removeProperty("display");
55		}
56		const svgXml = getElem("svg-xml-output") as HTMLTextAreaElement;
57		svgXml.value = "";
58
59		// Reset output images in case of early termination
60		const canvas = getElem("qrcode-canvas") as HTMLCanvasElement;
61		const svg = (document.getElementById("qrcode-svg") as Element) as SVGElement;
62		canvas.style.display = "none";
63		svg.style.display = "none";
64
65		// Returns a QrCode.Ecc object based on the radio buttons in the HTML form.
66		function getInputErrorCorrectionLevel(): qrcodegen.QrCode.Ecc {
67			if (getInput("errcorlvl-medium").checked)
68				return qrcodegen.QrCode.Ecc.MEDIUM;
69			else if (getInput("errcorlvl-quartile").checked)
70				return qrcodegen.QrCode.Ecc.QUARTILE;
71			else if (getInput("errcorlvl-high").checked)
72				return qrcodegen.QrCode.Ecc.HIGH;
73			else  // In case no radio button is depressed
74				return qrcodegen.QrCode.Ecc.LOW;
75		}
76
77		// Get form inputs and compute QR Code
78		const ecl: qrcodegen.QrCode.Ecc = getInputErrorCorrectionLevel();
79		const text: string = (getElem("text-input") as HTMLTextAreaElement).value;
80		const segs: Array<qrcodegen.QrSegment> = qrcodegen.QrSegment.makeSegments(text);
81		const minVer: number = parseInt(getInput("version-min-input").value, 10);
82		const maxVer: number = parseInt(getInput("version-max-input").value, 10);
83		const mask: number = parseInt(getInput("mask-input").value, 10);
84		const boostEcc: boolean = getInput("boost-ecc-input").checked;
85		const qr: qrcodegen.QrCode = qrcodegen.QrCode.encodeSegments(segs, ecl, minVer, maxVer, mask, boostEcc);
86
87		// Draw image output
88		const border: number = parseInt(getInput("border-input").value, 10);
89		if (border < 0 || border > 100)
90			return;
91		if (bitmapOutput) {
92			const scale: number = parseInt(getInput("scale-input").value, 10);
93			if (scale <= 0 || scale > 30)
94				return;
95			qr.drawCanvas(scale, border, canvas);
96			canvas.style.removeProperty("display");
97		} else {
98			const code: string = qr.toSvgString(border);
99			const viewBox: string = (/ viewBox="([^"]*)"/.exec(code) as RegExpExecArray)[1];
100			const pathD: string = (/ d="([^"]*)"/.exec(code) as RegExpExecArray)[1];
101			svg.setAttribute("viewBox", viewBox);
102			(svg.querySelector("path") as Element).setAttribute("d", pathD);
103			svg.style.removeProperty("display");
104			svgXml.value = qr.toSvgString(border);
105		}
106
107		// Returns a string to describe the given list of segments.
108		function describeSegments(segs: Array<qrcodegen.QrSegment>): string {
109			if (segs.length == 0)
110				return "none";
111			else if (segs.length == 1) {
112				const mode: qrcodegen.QrSegment.Mode = segs[0].mode;
113				const Mode = qrcodegen.QrSegment.Mode;
114				if (mode == Mode.NUMERIC     )  return "numeric";
115				if (mode == Mode.ALPHANUMERIC)  return "alphanumeric";
116				if (mode == Mode.BYTE        )  return "byte";
117				if (mode == Mode.KANJI       )  return "kanji";
118				return "unknown";
119			} else
120				return "multiple";
121		}
122
123		// Returns the number of Unicode code points in the given UTF-16 string.
124		function countUnicodeChars(str: string): number {
125			let result: number = 0;
126			for (let i = 0; i < str.length; i++, result++) {
127				const c: number = str.charCodeAt(i);
128				if (c < 0xD800 || c >= 0xE000)
129					continue;
130				else if (0xD800 <= c && c < 0xDC00 && i + 1 < str.length) {  // High surrogate
131					i++;
132					const d: number = str.charCodeAt(i);
133					if (0xDC00 <= d && d < 0xE000)  // Low surrogate
134						continue;
135				}
136				throw "Invalid UTF-16 string";
137			}
138			return result;
139		}
140
141		// Show the QR Code symbol's statistics as a string
142		getElem("statistics-output").textContent = `QR Code version = ${qr.version}, ` +
143			`mask pattern = ${qr.mask}, ` +
144			`character count = ${countUnicodeChars(text)},\n` +
145			`encoding mode = ${describeSegments(segs)}, ` +
146			`error correction = level ${"LMQH".charAt(qr.errorCorrectionLevel.ordinal)}, ` +
147			`data bits = ${qrcodegen.QrSegment.getTotalBits(segs, qr.version) as number}.`;
148	}
149
150
151	export function handleVersionMinMax(which: "min"|"max"): void {
152		const minElem: HTMLInputElement = getInput("version-min-input");
153		const maxElem: HTMLInputElement = getInput("version-max-input");
154		let minVal: number = parseInt(minElem.value, 10);
155		let maxVal: number = parseInt(maxElem.value, 10);
156		minVal = Math.max(Math.min(minVal, qrcodegen.QrCode.MAX_VERSION), qrcodegen.QrCode.MIN_VERSION);
157		maxVal = Math.max(Math.min(maxVal, qrcodegen.QrCode.MAX_VERSION), qrcodegen.QrCode.MIN_VERSION);
158		if (which == "min" && minVal > maxVal)
159			maxVal = minVal;
160		else if (which == "max" && maxVal < minVal)
161			minVal = maxVal;
162		minElem.value = minVal.toString();
163		maxElem.value = maxVal.toString();
164		redrawQrCode();
165	}
166
167
168	function getElem(id: string): HTMLElement {
169		const result: HTMLElement|null = document.getElementById(id);
170		if (result instanceof HTMLElement)
171			return result;
172		throw "Assertion error";
173	}
174
175
176	function getInput(id: string): HTMLInputElement {
177		const result: HTMLElement = getElem(id);
178		if (result instanceof HTMLInputElement)
179			return result;
180		throw "Assertion error";
181	}
182
183
184	initialize();
185}
186