thebespokepixel/trucolor

/* ─────────╮
 │ trucolor │ Chalk-style nested functions
 ╰──────────┴─────────────────────────────────────────────────────────────────── */
/* eslint no-proto:0 */

import escStringRE from 'escape-string-regexp'

class Chalkish {
    constructor(styles) {
        const styleFactory = (collection => {
            for (const key of Object.keys(styles)) {
                styles[key].closeRE = new RegExp(escStringRE(styles[key].out), 'g')
                collection[key] = {
                    get: () => makePainter.call([...this._styles, ...key]),
                }
            }

            return collection
        })({})

        const proto = Object.defineProperties(() => {}, styleFactory)

        function applyPaint(content) {
            let i = this._styles.length
            while (i--) {
                const sgrPair = styles[this._styles[i]]
                content = sgrPair.in + content.replace(sgrPair.closeRE, sgrPair.in) + sgrPair.out
            }

            return content
        }

        function makePainter(styles) {
            const painter = (...args) => applyPaint.apply(painter, args)
            painter._styles = styles
            painter.__proto__ = proto
            return painter
        }

        Object.defineProperties(Chalkish.prototype, (collection => {
            for (const name of Object.keys(styles)) {
                collection[name] = {
                    get: () => makePainter.call(this, [name]),
                }
            }

            return collection
        })({}))
    }
}

export default function chalk(palette) {
    return new Chalkish(palette)
}