tiny-bin/dist/objects/logger.js

A library for building tiny and beautiful command line apps.

/* IMPORT */
import stringWidth from 'fast-string-width';
import colors from 'tiny-colors';
import Addon from './addon.js';
import { identity, stripAnsi } from '../utils.js';
/* MAIN */
class Logger extends Addon {
    /* CONSTRUCTOR */
    constructor(bin, handler) {
        super(bin);
        this.indentationLevel = 0;
        this.indentation = '  ';
        this.handler = handler;
    }
    /* API */
    indent() {
        this.indentationLevel += 1;
    }
    dedent() {
        this.indentationLevel -= 1;
    }
    group(name, fn) {
        this.print(colors.bold(name.toUpperCase()));
        this.indent();
        this.print();
        fn();
        this.print();
        this.dedent();
    }
    print(message = '') {
        const colorize = this.bin.metadata.colors ? identity : stripAnsi;
        this.handler(colorize(`${this.indentation.repeat(this.indentationLevel)}${message}`));
    }
    table(rows, mode = 'line') {
        const rowsLengths = rows.map(row => row.map(cell => stringWidth(cell)));
        const maxLengths = rowsLengths[0].map((_, j) => Math.max(...rowsLengths.map((_, i) => rowsLengths[i][j])));
        if (mode === 'lines' && maxLengths.length === 2) { //TODO: Generalize this, even though it's not needed yet
            const COLUMN = 30; //TODO: Make this customizable
            const PADDING = 4;
            rows.forEach(([left, right], i) => {
                const leftNedded = stringWidth(left) + PADDING;
                const leftAvailable = COLUMN - leftNedded;
                const leftShortEnough = (leftAvailable >= 2);
                const rightLines = right.trim().split(/\r?\n|\r/g);
                const line = [left, rightLines.map((line, i) => (leftShortEnough && !i) ? `${' '.repeat(leftAvailable)}${line}` : `${i ? '' : '\n'}${' '.repeat(COLUMN)}${line}`).join('\n')].join('');
                this.print(line);
            });
        }
        else if (mode === 'line') {
            rows.forEach((row, i) => {
                const line = row.map((value, j) => {
                    const paddingLength = (j === row.length - 1) ? 0 : Math.max(0, 1 + maxLengths[j] - rowsLengths[i][j]);
                    const padding = ' '.repeat(paddingLength);
                    return `${value}${padding}`;
                }).join(' ');
                this.print(line);
            });
        }
        else {
            throw new Error('Unsupported printing mode');
        }
    }
}
/* EXPORT */
export default Logger;