import Arrays from '../../util/Arrays';
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/**
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* Symbol Character Placement Program. Adapted from Annex M.1 in ISO/IEC 16022:2000(E).
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*/
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class DefaultPlacement {
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/**
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* Main constructor
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*
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* @param codewords the codewords to place
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* @param numcols the number of columns
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* @param numrows the number of rows
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*/
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constructor(codewords, numcols, numrows) {
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this.codewords = codewords;
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this.numcols = numcols;
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this.numrows = numrows;
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this.bits = new Uint8Array(numcols * numrows);
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Arrays.fill(this.bits, 2); // Initialize with "not set" value
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}
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getNumrows() {
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return this.numrows;
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}
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getNumcols() {
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return this.numcols;
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}
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getBits() {
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return this.bits;
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}
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getBit(col, row) {
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return this.bits[row * this.numcols + col] === 1;
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}
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setBit(col, row, bit) {
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this.bits[row * this.numcols + col] = bit ? 1 : 0;
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}
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noBit(col, row) {
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return this.bits[row * this.numcols + col] === 2;
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}
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place() {
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let pos = 0;
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let row = 4;
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let col = 0;
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do {
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// repeatedly first check for one of the special corner cases, then...
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if (row === this.numrows && col === 0) {
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this.corner1(pos++);
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}
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if (row === this.numrows - 2 && col === 0 && this.numcols % 4 !== 0) {
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this.corner2(pos++);
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}
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if (row === this.numrows - 2 && col === 0 && this.numcols % 8 === 4) {
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this.corner3(pos++);
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}
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if (row === this.numrows + 4 && col === 2 && this.numcols % 8 === 0) {
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this.corner4(pos++);
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}
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// sweep upward diagonally, inserting successive characters...
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do {
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if (row < this.numrows && col >= 0 && this.noBit(col, row)) {
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this.utah(row, col, pos++);
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}
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row -= 2;
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col += 2;
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} while (row >= 0 && col < this.numcols);
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row++;
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col += 3;
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// and then sweep downward diagonally, inserting successive characters, ...
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do {
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if (row >= 0 && col < this.numcols && this.noBit(col, row)) {
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this.utah(row, col, pos++);
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}
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row += 2;
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col -= 2;
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} while (row < this.numrows && col >= 0);
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row += 3;
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col++;
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// ...until the entire array is scanned
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} while (row < this.numrows || col < this.numcols);
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// Lastly, if the lower right-hand corner is untouched, fill in fixed pattern
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if (this.noBit(this.numcols - 1, this.numrows - 1)) {
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this.setBit(this.numcols - 1, this.numrows - 1, true);
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this.setBit(this.numcols - 2, this.numrows - 2, true);
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}
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}
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module(row, col, pos, bit) {
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if (row < 0) {
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row += this.numrows;
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col += 4 - ((this.numrows + 4) % 8);
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}
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if (col < 0) {
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col += this.numcols;
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row += 4 - ((this.numcols + 4) % 8);
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}
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// Note the conversion:
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let v = this.codewords.charCodeAt(pos);
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v &= 1 << (8 - bit);
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this.setBit(col, row, v !== 0);
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}
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/**
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* Places the 8 bits of a utah-shaped symbol character in ECC200.
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*
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* @param row the row
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* @param col the column
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* @param pos character position
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*/
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utah(row, col, pos) {
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this.module(row - 2, col - 2, pos, 1);
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this.module(row - 2, col - 1, pos, 2);
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this.module(row - 1, col - 2, pos, 3);
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this.module(row - 1, col - 1, pos, 4);
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this.module(row - 1, col, pos, 5);
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this.module(row, col - 2, pos, 6);
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this.module(row, col - 1, pos, 7);
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this.module(row, col, pos, 8);
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}
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corner1(pos) {
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this.module(this.numrows - 1, 0, pos, 1);
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this.module(this.numrows - 1, 1, pos, 2);
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this.module(this.numrows - 1, 2, pos, 3);
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this.module(0, this.numcols - 2, pos, 4);
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this.module(0, this.numcols - 1, pos, 5);
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this.module(1, this.numcols - 1, pos, 6);
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this.module(2, this.numcols - 1, pos, 7);
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this.module(3, this.numcols - 1, pos, 8);
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}
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corner2(pos) {
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this.module(this.numrows - 3, 0, pos, 1);
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this.module(this.numrows - 2, 0, pos, 2);
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this.module(this.numrows - 1, 0, pos, 3);
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this.module(0, this.numcols - 4, pos, 4);
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this.module(0, this.numcols - 3, pos, 5);
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this.module(0, this.numcols - 2, pos, 6);
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this.module(0, this.numcols - 1, pos, 7);
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this.module(1, this.numcols - 1, pos, 8);
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}
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corner3(pos) {
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this.module(this.numrows - 3, 0, pos, 1);
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this.module(this.numrows - 2, 0, pos, 2);
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this.module(this.numrows - 1, 0, pos, 3);
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this.module(0, this.numcols - 2, pos, 4);
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this.module(0, this.numcols - 1, pos, 5);
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this.module(1, this.numcols - 1, pos, 6);
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this.module(2, this.numcols - 1, pos, 7);
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this.module(3, this.numcols - 1, pos, 8);
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}
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corner4(pos) {
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this.module(this.numrows - 1, 0, pos, 1);
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this.module(this.numrows - 1, this.numcols - 1, pos, 2);
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this.module(0, this.numcols - 3, pos, 3);
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this.module(0, this.numcols - 2, pos, 4);
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this.module(0, this.numcols - 1, pos, 5);
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this.module(1, this.numcols - 3, pos, 6);
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this.module(1, this.numcols - 2, pos, 7);
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this.module(1, this.numcols - 1, pos, 8);
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}
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}
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export default DefaultPlacement;
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