Mini Shell

//---------------------------------------------------------------------
// QRCode for JavaScript
//
// Copyright (c) 2009 Kazuhiko Arase
//
// URL: http://www.d-project.com/
//
// Licensed under the MIT license:
//   http://www.opensource.org/licenses/mit-license.php
//
// The word "QR Code" is registered trademark of 
// DENSO WAVE INCORPORATED
//   http://www.denso-wave.com/qrcode/faqpatent-e.html
//
//---------------------------------------------------------------------
// Modified to work in node for this project (and some refactoring)
//---------------------------------------------------------------------

var QR8bitByte = require('./QR8bitByte');
var QRUtil = require('./QRUtil');
var QRPolynomial = require('./QRPolynomial');
var QRRSBlock = require('./QRRSBlock');
var QRBitBuffer = require('./QRBitBuffer');

function QRCode(typeNumber, errorCorrectLevel) {
	this.typeNumber = typeNumber;
	this.errorCorrectLevel = errorCorrectLevel;
	this.modules = null;
	this.moduleCount = 0;
	this.dataCache = null;
	this.dataList = [];
}

QRCode.prototype = {
	
	addData : function(data) {
		var newData = new QR8bitByte(data);
		this.dataList.push(newData);
		this.dataCache = null;
	},
	
	isDark : function(row, col) {
		if (row < 0 || this.moduleCount <= row || col < 0 || this.moduleCount <= col) {
			throw new Error(row + "," + col);
		}
		return this.modules[row][col];
	},

	getModuleCount : function() {
		return this.moduleCount;
	},
	
	make : function() {
		// Calculate automatically typeNumber if provided is < 1
		if (this.typeNumber < 1 ){
			var typeNumber = 1;
			for (typeNumber = 1; typeNumber < 40; typeNumber++) {
				var rsBlocks = QRRSBlock.getRSBlocks(typeNumber, this.errorCorrectLevel);

				var buffer = new QRBitBuffer();
				var totalDataCount = 0;
				for (var i = 0; i < rsBlocks.length; i++) {
					totalDataCount += rsBlocks[i].dataCount;
				}

				for (var x = 0; x < this.dataList.length; x++) {
					var data = this.dataList[x];
					buffer.put(data.mode, 4);
					buffer.put(data.getLength(), QRUtil.getLengthInBits(data.mode, typeNumber) );
					data.write(buffer);
				}
				if (buffer.getLengthInBits() <= totalDataCount * 8)
					break;
			}
			this.typeNumber = typeNumber;
		}
		this.makeImpl(false, this.getBestMaskPattern() );
	},
	
	makeImpl : function(test, maskPattern) {
		
		this.moduleCount = this.typeNumber * 4 + 17;
		this.modules = new Array(this.moduleCount);
		
		for (var row = 0; row < this.moduleCount; row++) {
			
			this.modules[row] = new Array(this.moduleCount);
			
			for (var col = 0; col < this.moduleCount; col++) {
				this.modules[row][col] = null;//(col + row) % 3;
			}
		}
	
		this.setupPositionProbePattern(0, 0);
		this.setupPositionProbePattern(this.moduleCount - 7, 0);
		this.setupPositionProbePattern(0, this.moduleCount - 7);
		this.setupPositionAdjustPattern();
		this.setupTimingPattern();
		this.setupTypeInfo(test, maskPattern);
		
		if (this.typeNumber >= 7) {
			this.setupTypeNumber(test);
		}
	
		if (this.dataCache === null) {
			this.dataCache = QRCode.createData(this.typeNumber, this.errorCorrectLevel, this.dataList);
		}
	
		this.mapData(this.dataCache, maskPattern);
	},

	setupPositionProbePattern : function(row, col)  {
		
		for (var r = -1; r <= 7; r++) {
			
			if (row + r <= -1 || this.moduleCount <= row + r) continue;
			
			for (var c = -1; c <= 7; c++) {
				
				if (col + c <= -1 || this.moduleCount <= col + c) continue;
				
				if ( (0 <= r && r <= 6 && (c === 0 || c === 6) ) || 
                     (0 <= c && c <= 6 && (r === 0 || r === 6) ) || 
                     (2 <= r && r <= 4 && 2 <= c && c <= 4) ) {
					this.modules[row + r][col + c] = true;
				} else {
					this.modules[row + r][col + c] = false;
				}
			}		
		}		
	},
	
	getBestMaskPattern : function() {
	
		var minLostPoint = 0;
		var pattern = 0;
	
		for (var i = 0; i < 8; i++) {
			
			this.makeImpl(true, i);
	
			var lostPoint = QRUtil.getLostPoint(this);
	
			if (i === 0 || minLostPoint >  lostPoint) {
				minLostPoint = lostPoint;
				pattern = i;
			}
		}
	
		return pattern;
	},
	
	createMovieClip : function(target_mc, instance_name, depth) {
	
		var qr_mc = target_mc.createEmptyMovieClip(instance_name, depth);
		var cs = 1;
	
		this.make();

		for (var row = 0; row < this.modules.length; row++) {
			
			var y = row * cs;
			
			for (var col = 0; col < this.modules[row].length; col++) {
	
				var x = col * cs;
				var dark = this.modules[row][col];
			
				if (dark) {
					qr_mc.beginFill(0, 100);
					qr_mc.moveTo(x, y);
					qr_mc.lineTo(x + cs, y);
					qr_mc.lineTo(x + cs, y + cs);
					qr_mc.lineTo(x, y + cs);
					qr_mc.endFill();
				}
			}
		}
		
		return qr_mc;
	},

	setupTimingPattern : function() {
		
		for (var r = 8; r < this.moduleCount - 8; r++) {
			if (this.modules[r][6] !== null) {
				continue;
			}
			this.modules[r][6] = (r % 2 === 0);
		}
	
		for (var c = 8; c < this.moduleCount - 8; c++) {
			if (this.modules[6][c] !== null) {
				continue;
			}
			this.modules[6][c] = (c % 2 === 0);
		}
	},
	
	setupPositionAdjustPattern : function() {
	
		var pos = QRUtil.getPatternPosition(this.typeNumber);
		
		for (var i = 0; i < pos.length; i++) {
		
			for (var j = 0; j < pos.length; j++) {
			
				var row = pos[i];
				var col = pos[j];
				
				if (this.modules[row][col] !== null) {
					continue;
				}
				
				for (var r = -2; r <= 2; r++) {
				
					for (var c = -2; c <= 2; c++) {
					
						if (Math.abs(r) === 2 || 
                            Math.abs(c) === 2 ||
                            (r === 0 && c === 0) ) {
							this.modules[row + r][col + c] = true;
						} else {
							this.modules[row + r][col + c] = false;
						}
					}
				}
			}
		}
	},
	
	setupTypeNumber : function(test) {
	
		var bits = QRUtil.getBCHTypeNumber(this.typeNumber);
        var mod;
	
		for (var i = 0; i < 18; i++) {
			mod = (!test && ( (bits >> i) & 1) === 1);
			this.modules[Math.floor(i / 3)][i % 3 + this.moduleCount - 8 - 3] = mod;
		}
	
		for (var x = 0; x < 18; x++) {
			mod = (!test && ( (bits >> x) & 1) === 1);
			this.modules[x % 3 + this.moduleCount - 8 - 3][Math.floor(x / 3)] = mod;
		}
	},
	
	setupTypeInfo : function(test, maskPattern) {
	
		var data = (this.errorCorrectLevel << 3) | maskPattern;
		var bits = QRUtil.getBCHTypeInfo(data);
        var mod;
	
		// vertical		
		for (var v = 0; v < 15; v++) {
	
			mod = (!test && ( (bits >> v) & 1) === 1);
	
			if (v < 6) {
				this.modules[v][8] = mod;
			} else if (v < 8) {
				this.modules[v + 1][8] = mod;
			} else {
				this.modules[this.moduleCount - 15 + v][8] = mod;
			}
		}
	
		// horizontal
		for (var h = 0; h < 15; h++) {
	
			mod = (!test && ( (bits >> h) & 1) === 1);
			
			if (h < 8) {
				this.modules[8][this.moduleCount - h - 1] = mod;
			} else if (h < 9) {
				this.modules[8][15 - h - 1 + 1] = mod;
			} else {
				this.modules[8][15 - h - 1] = mod;
			}
		}
	
		// fixed module
		this.modules[this.moduleCount - 8][8] = (!test);
	
	},
	
	mapData : function(data, maskPattern) {
		
		var inc = -1;
		var row = this.moduleCount - 1;
		var bitIndex = 7;
		var byteIndex = 0;
		
		for (var col = this.moduleCount - 1; col > 0; col -= 2) {
	
			if (col === 6) col--;
	
			while (true) {
	
				for (var c = 0; c < 2; c++) {
					
					if (this.modules[row][col - c] === null) {
						
						var dark = false;
	
						if (byteIndex < data.length) {
							dark = ( ( (data[byteIndex] >>> bitIndex) & 1) === 1);
						}
	
						var mask = QRUtil.getMask(maskPattern, row, col - c);
	
						if (mask) {
							dark = !dark;
						}
						
						this.modules[row][col - c] = dark;
						bitIndex--;
	
						if (bitIndex === -1) {
							byteIndex++;
							bitIndex = 7;
						}
					}
				}
								
				row += inc;
	
				if (row < 0 || this.moduleCount <= row) {
					row -= inc;
					inc = -inc;
					break;
				}
			}
		}
		
	}

};

QRCode.PAD0 = 0xEC;
QRCode.PAD1 = 0x11;

QRCode.createData = function(typeNumber, errorCorrectLevel, dataList) {
	
	var rsBlocks = QRRSBlock.getRSBlocks(typeNumber, errorCorrectLevel);
	
	var buffer = new QRBitBuffer();
	
	for (var i = 0; i < dataList.length; i++) {
		var data = dataList[i];
		buffer.put(data.mode, 4);
		buffer.put(data.getLength(), QRUtil.getLengthInBits(data.mode, typeNumber) );
		data.write(buffer);
	}

	// calc num max data.
	var totalDataCount = 0;
	for (var x = 0; x < rsBlocks.length; x++) {
		totalDataCount += rsBlocks[x].dataCount;
	}

	if (buffer.getLengthInBits() > totalDataCount * 8) {
		throw new Error("code length overflow. (" + 
            buffer.getLengthInBits() + 
            ">" +  
            totalDataCount * 8 + 
            ")");
	}

	// end code
	if (buffer.getLengthInBits() + 4 <= totalDataCount * 8) {
		buffer.put(0, 4);
	}

	// padding
	while (buffer.getLengthInBits() % 8 !== 0) {
		buffer.putBit(false);
	}

	// padding
	while (true) {
		
		if (buffer.getLengthInBits() >= totalDataCount * 8) {
			break;
		}
		buffer.put(QRCode.PAD0, 8);
		
		if (buffer.getLengthInBits() >= totalDataCount * 8) {
			break;
		}
		buffer.put(QRCode.PAD1, 8);
	}

	return QRCode.createBytes(buffer, rsBlocks);
};

QRCode.createBytes = function(buffer, rsBlocks) {

	var offset = 0;
	
	var maxDcCount = 0;
	var maxEcCount = 0;
	
	var dcdata = new Array(rsBlocks.length);
	var ecdata = new Array(rsBlocks.length);
	
	for (var r = 0; r < rsBlocks.length; r++) {

		var dcCount = rsBlocks[r].dataCount;
		var ecCount = rsBlocks[r].totalCount - dcCount;

		maxDcCount = Math.max(maxDcCount, dcCount);
		maxEcCount = Math.max(maxEcCount, ecCount);
		
		dcdata[r] = new Array(dcCount);
		
		for (var i = 0; i < dcdata[r].length; i++) {
			dcdata[r][i] = 0xff & buffer.buffer[i + offset];
		}
		offset += dcCount;
		
		var rsPoly = QRUtil.getErrorCorrectPolynomial(ecCount);
		var rawPoly = new QRPolynomial(dcdata[r], rsPoly.getLength() - 1);

		var modPoly = rawPoly.mod(rsPoly);
		ecdata[r] = new Array(rsPoly.getLength() - 1);
		for (var x = 0; x < ecdata[r].length; x++) {
            var modIndex = x + modPoly.getLength() - ecdata[r].length;
			ecdata[r][x] = (modIndex >= 0)? modPoly.get(modIndex) : 0;
		}

	}
	
	var totalCodeCount = 0;
	for (var y = 0; y < rsBlocks.length; y++) {
		totalCodeCount += rsBlocks[y].totalCount;
	}

	var data = new Array(totalCodeCount);
	var index = 0;

	for (var z = 0; z < maxDcCount; z++) {
		for (var s = 0; s < rsBlocks.length; s++) {
			if (z < dcdata[s].length) {
				data[index++] = dcdata[s][z];
			}
		}
	}

	for (var xx = 0; xx < maxEcCount; xx++) {
		for (var t = 0; t < rsBlocks.length; t++) {
			if (xx < ecdata[t].length) {
				data[index++] = ecdata[t][xx];
			}
		}
	}

	return data;

};

module.exports = QRCode;