nadesiko3/core/src/nako_csv.mjs

Japanese Programming Language

export const options = {
    delimiter: ',',
    eol: '\r\n'
};
export function resetEnv() {
    options.delimiter = ',';
    options.eol = '\r\n';
}
export function parse(txt, delimiter = undefined) {
    // delimiter
    if (delimiter === undefined) {
        delimiter = options.delimiter;
    }
    // check txt
    txt = '' + txt + '\n';
    // convert CRLF to LF, and CR to LF
    txt = txt.replace(/(\r\n|\r)/g, '\n');
    // trim right
    txt = txt.replace(/\s+$/, '') + '\n';
    // set pattern
    const patToDelim = '^(.*?)([\\' + delimiter + '\\n])';
    const reToDelim = new RegExp(patToDelim);
    // if value is number then convert to float
    const convType = function (v) {
        if (typeof (v) === 'string') {
            if (v.search(/^[0-9.]+$/) >= 0) {
                v = parseFloat(v); // convert number
            }
        }
        return v;
    };
    // parse txt
    const res = [];
    let cells = [];
    let c = '';
    while (txt !== '') {
        // first check delimiter (because /^\s+/ skip delimiter'\t') (#3)
        c = txt.charAt(0);
        if (c === delimiter) {
            txt = txt.substring(1);
            cells.push('');
            continue;
        }
        // second check LF (#7)
        if (c === '\n') {
            cells.push('');
            res.push(cells);
            cells = [];
            txt = txt.substring(1);
            continue;
        }
        // trim white space
        txt = txt.replace(/^\s+/, '');
        c = txt.charAt(0);
        // no data
        if (c === delimiter) {
            console.log('delimiter');
            cells.push('');
            txt = txt.substring(delimiter.length);
            continue;
        }
        // written using the dialect of Excel
        if (c === '=' && txt.charAt(1) === '"') {
            txt = txt.substring(1);
            continue;
        }
        // number or simple string
        if (c !== '"') { // number or simple str
            const m = reToDelim.exec(txt);
            if (!m) {
                cells.push(convType(txt));
                res.push(cells);
                cells = [];
                break;
            }
            if (m[2] === '\n') {
                cells.push(convType(m[1]));
                res.push(cells);
                cells = [];
            }
            else if (m[2] === delimiter) {
                cells.push(convType(m[1]));
            }
            txt = txt.substring(m[0].length);
            continue;
        }
        // "" ... blank data
        if (txt.substring(0, 2) === '""') {
            cells.push('');
            txt = txt.substring(2);
            continue;
        }
        // "..."
        let i = 1;
        let s = '';
        while (i < txt.length) {
            const c1 = txt.charAt(i);
            const c2 = txt.charAt(i + 1);
            // console.log("@" + c1 + c2);
            // 2quote => 1quote char
            if (c1 === '"' && c2 === '"') {
                i += 2;
                s += '"';
                continue;
            }
            if (c1 === '"') {
                i++;
                if (c2 === delimiter) {
                    i++;
                    cells.push(convType(s));
                    s = '';
                    break;
                }
                if (c2 === '\n') {
                    i++;
                    cells.push(convType(s));
                    res.push(cells);
                    cells = [];
                    break;
                }
                // if (c2 === " " || c2 === "\t") {
                i++;
                continue;
            }
            s += c1;
            i++;
        }
        txt = txt.substr(i);
    }
    if (cells.length > 0)
        res.push(cells);
    return res;
}
// convert 2D array to CSV string
export function stringify(ary, delimiter = undefined, eol = undefined) {
    // check arguments
    if (delimiter === undefined) {
        delimiter = options.delimiter;
    }
    if (eol === undefined) {
        eol = options.eol;
    }
    const valueConv = genValueConverter(delimiter);
    if (ary === undefined)
        return '';
    let r = '';
    for (let i = 0; i < ary.length; i++) {
        const cells = ary[i];
        if (cells === undefined) {
            r += eol;
            continue;
        }
        for (let j = 0; j < cells.length; j++) {
            cells[j] = valueConv(cells[j]);
        }
        r += cells.join(delimiter) + eol;
    }
    // replace return code
    r = r.replace(/(\r\n|\r|\n)/g, eol);
    return r;
}
export function replaceEolMark(eol) {
    eol = eol.replace(/\n\r/g, '[CRLF]');
    eol = eol.replace(/\r/g, '[CR]');
    eol = eol.replace(/\n/g, '[LF]');
    return eol;
}
function genValueConverter(delimiter) {
    return function (s) {
        s = '' + s;
        let fQuot = false;
        if (s.indexOf('\n') >= 0 || s.indexOf('\r') >= 0) {
            fQuot = true;
        }
        if (s.indexOf(delimiter) >= 0) {
            fQuot = true;
        }
        if (s.indexOf('"') >= 0) {
            fQuot = true;
            s = s.replace(/"/g, '""');
        }
        if (fQuot)
            s = '"' + s + '"';
        return s;
    };
}