thebespokepixel/truwrap

/* ────────╮
 │ truwrap │ Smarter 24bit SGR aware console text wrapping
 ╰─────────┴─────────────────────────────────────────────────────────────────── */

import columnify from 'columnify'
import createWrapTool from './lib/wrap-tool.js'
import createImage from './lib/image.js'
import parsePanel from './lib/panel.js'

/**
 * Truwrap - take input from write() and composed a wrapped text block.
 *
 * @class      Truwrap (name)
 */
export class Truwrap {
    /**
     * The base Truwrap instance/api
     *
     * @param      {Object}           options                options object
     * @param      {number}           [options.left=2]       Left margin.
     * @param      {number}           [options.right=2]      Right margin.
     * @param      {number}           options.width          Manually set view width.
     * @param      {string}           [options.mode='soft']  [soft | hyphen | hard | keep | container
     * @param      {number}           [options.tabWidth=4]   Desired width of TAB character.
     * @param      {Stream.writable}  options.outStream      Where to direct output.
     * @param      {Regexp}           options.tokenRegex     Override the tokenisers regexp.
     */
    constructor({
        left = 2,
        right = 2,
        width,
        mode = 'soft',
        tabWidth = 4,
        outStream,
        tokenRegex
    }) {
        this.outStream = outStream
        this.buffer = ''
        this.mode = mode

        this.ttyActive = Boolean(width || (outStream && outStream.isTTY) || /keep|container/.test(mode))

        this.ttyWidth = (() => {
            if (width) {
                return width
            }

            if (outStream && outStream.isTTY) {
                return outStream.columns || outStream.getWindowSize()[0]
            }

            return 80
        })()

        this.viewWidth = (() => {
            if (this.ttyWidth - left - right > 1) {
                return this.ttyWidth - left - right
            }

            return 2
        })()

        this.viewHandler = (() => {
            if (this.ttyActive && mode !== 'container') {
                return createWrapTool({
                    mode: this.mode,
                    left,
                    width: this.viewWidth,
                    tabWidth,
                    tokenRegex
                })
            }

            return {}
        })()
    }

    /**
     * End a block, setting blocking mode and flushing buffers if needed.
     *
     * @return     {string}  The wrapped output, has side effect of writing to stream if defined.
     */
    end() {
        if (this.outStream) {
            if (this.outStream._isStdio) {
                this.outStream.write('\n')
            } else {
                this.outStream.end()
            }
        }

        const output = this.buffer
        this.buffer=''

        return output
    }

    /**
     * Fetch the width in characters of the wrapping view.
     *
     * @return     {number}  The width.
     */
    getWidth() {
        switch (true) {
            case !this.ttyActive:
                return this.ttyWidth
            case this.mode === 'container':
                return this.ttyWidth
            default:
                return this.viewWidth
        }
    }

    /**
     * Create a multicolumn panel within this view
     *
     * @param      {panelObject}  content_       Object for columnify
     * @param      {Object}       configuration  Configuration for columnify
     * @return     {Object}       this instance, to allow chaining
     */
    panel(content_, configuration) {
        const content = (() => {
            switch (true) {
                case !this.ttyActive:
                    return columnify(content_, configuration)
                case this.mode === 'container':
                    return columnify(content_, configuration)
                default:
                    return this.viewHandler.wrap(columnify(content_, configuration))
            }
        })()

        if (this.outStream) {
            this.outStream.write(content)
        }

        this.buffer += content

        return this
    }

    /**
     * Generate linebreaks within this view
     *
     * @param  {number} newlines   number of new lines to add.
     * @return {Object} this instance, to allow chaining
     */
    break(newlines = 1) {
        const content = '\n'.repeat(newlines)
        if (this.outStream) {
            this.outStream.write(content)
        }

        this.buffer += content

        return this
    }

    /**
     * Similar to css' clear. Write a clearing newline to the stream.
     *
     * @return     {Object}  this instance, to allow chaining
     */
    clear() {
        const content = '\n'
        if (this.outStream) {
            this.outStream.write(content)
        }

        this.buffer += content

        return this
    }

    /**
     * Write text via the wrapping logic
     *
     * @param      {string}  content_  The content
     * @return     {Object}  this instance, to allow chaining
     */
    write(content_) {
        const content = (() => {
            switch (true) {
                case !this.ttyActive:
                    return content_
                case this.mode === 'container':
                    return content_
                default:
                    return this.viewHandler.wrap(content_)
            }
        })()

        if (this.outStream) {
            this.outStream.write(content)
        }

        this.buffer += content

        return this
    }
}

/**
 * Create a text wrapping instance.
 *
 * @param      {Object}           options                options object
 * @param      {number}           [options.left=2]       Left margin.
 * @param      {number}           [options.right=2]      Right margin.
 * @param      {number}           options.width          Manually set view width.
 * @param      {string}           [options.mode='soft']  [soft | hyphen | hard | keep | container
 * @param      {number}           [options.tabWidth=4]   Desired width of TAB character.
 * @param      {Stream.writable}  options.outStream      Where to direct output.
 * @param      {Regexp}           options.tokenRegex     Override the tokenisers regexp.
 * @return     {Truwrap}  { description_of_the_return_value }

 */
export function truwrap(options) {
    return new Truwrap(options)
}

export {createImage, parsePanel}