Leantime/dev/DWGViewer/libs/dxf-parser/DxfArrayScanner.js

/**
 * DxfArrayScanner
 *
 * Based off the AutoCad 2012 DXF Reference
 * http://images.autodesk.com/adsk/files/autocad_2012_pdf_dxf-reference_enu.pdf
 *
 * Reads through an array representing lines of a dxf file. Takes an array and
 * provides an easy interface to extract group code and value pairs.
 * @param data - an array where each element represents a line in the dxf file
 * @constructor
 */
export default class DxfArrayScanner {
    constructor(data) {
        this._pointer = 0;
        this._eof = false;
        this._data = data;
    }
    /**
     * Gets the next group (code, value) from the array. A group is two consecutive elements
     * in the array. The first is the code, the second is the value.
     * @returns {{code: Number}|*}
     */
    next() {
        if (!this.hasNext()) {
            if (!this._eof)
                throw new Error('Unexpected end of input: EOF group not read before end of file. Ended on code ' + this._data[this._pointer]);
            else
                throw new Error('Cannot call \'next\' after EOF group has been read');
        }
        const group = {
            code: parseInt(this._data[this._pointer])
        };
        this._pointer++;
        group.value = parseGroupValue(group.code, this._data[this._pointer].trim());
        this._pointer++;
        if (group.code === 0 && group.value === 'EOF')
            this._eof = true;
        this.lastReadGroup = group;
        return group;
    }
    peek() {
        if (!this.hasNext()) {
            if (!this._eof)
                throw new Error('Unexpected end of input: EOF group not read before end of file. Ended on code ' + this._data[this._pointer]);
            else
                throw new Error('Cannot call \'next\' after EOF group has been read');
        }
        const group = {
            code: parseInt(this._data[this._pointer])
        };
        group.value = parseGroupValue(group.code, this._data[this._pointer + 1].trim());
        return group;
    }
    rewind(numberOfGroups = 1) {
        this._pointer = this._pointer - numberOfGroups * 2;
    }
    /**
     * Returns true if there is another code/value pair (2 elements in the array).
     * @returns {boolean}
     */
    hasNext() {
        // Check if we have read EOF group code
        if (this._eof) {
            return false;
        }
        // We need to be sure there are two lines available
        if (this._pointer > this._data.length - 2) {
            return false;
        }
        return true;
    }
    /**
     * Returns true if the scanner is at the end of the array
     * @returns {boolean}
     */
    isEOF() {
        return this._eof;
    }
}
/**
 * Parse a value to its proper type.
 * See pages 3 - 10 of the AutoCad DXF 2012 reference given at the top of this file
 *
 * @param code
 * @param value
 * @returns {*}
 */
function parseGroupValue(code, value) {
    if (code <= 9)
        return value;
    if (code >= 10 && code <= 59)
        return parseFloat(value);
    if (code >= 60 && code <= 99)
        return parseInt(value);
    if (code >= 100 && code <= 109)
        return value;
    if (code >= 110 && code <= 149)
        return parseFloat(value);
    if (code >= 160 && code <= 179)
        return parseInt(value);
    if (code >= 210 && code <= 239)
        return parseFloat(value);
    if (code >= 270 && code <= 289)
        return parseInt(value);
    if (code >= 290 && code <= 299)
        return parseBoolean(value);
    if (code >= 300 && code <= 369)
        return value;
    if (code >= 370 && code <= 389)
        return parseInt(value);
    if (code >= 390 && code <= 399)
        return value;
    if (code >= 400 && code <= 409)
        return parseInt(value);
    if (code >= 410 && code <= 419)
        return value;
    if (code >= 420 && code <= 429)
        return parseInt(value);
    if (code >= 430 && code <= 439)
        return value;
    if (code >= 440 && code <= 459)
        return parseInt(value);
    if (code >= 460 && code <= 469)
        return parseFloat(value);
    if (code >= 470 && code <= 481)
        return value;
    if (code === 999)
        return value;
    if (code >= 1000 && code <= 1009)
        return value;
    if (code >= 1010 && code <= 1059)
        return parseFloat(value);
    if (code >= 1060 && code <= 1071)
        return parseInt(value);
    console.log('WARNING: Group code does not have a defined type: %j', { code: code, value: value });
    return value;
}
/**
 * Parse a boolean according to a 1 or 0 value
 * @param str
 * @returns {boolean}
 */
function parseBoolean(str) {
    if (str === '0')
        return false;
    if (str === '1')
        return true;
    throw TypeError('String \'' + str + '\' cannot be cast to Boolean type');
}