make-block.js

'use strict';

import fs from 'fs';
import path from 'path';
import { createInterface } from 'readline';
const rl = createInterface(process.stdin, process.stdout);

// folder with all blocks
const BLOCKS_DIR = path.join(__dirname, 'app/blocks');

// //////////////////////////////////////////////////////////////////////////////////////////////////

// default content for files in new block
const fileSources = {
	jade: `mixin {blockName}()\n\t+b.{blockName}&attributes(attributes)\n\t\tblock\n`,
	styl: `.{blockName}\n\tdisplay block\n`
};

function validateBlockName(blockName) {
	return new Promise((resolve, reject) => {
		const isValid = /^(\d|\w|-)+$/.test(blockName);

		if (isValid) {
			resolve(isValid);
		} else {
			const errMsg = (
				`ERR>>> An incorrect block name '${blockName}'\n` +
				`ERR>>> A block name must include letters, numbers & the minus symbol.`
			);
			reject(errMsg);
		}
	});
}

function directoryExist(blockPath, blockName) {
	return new Promise((resolve, reject) => {
		fs.stat(blockPath, notExist => {
			if (notExist) {
				resolve();
			} else {
				reject(`ERR>>> The block '${blockName}' already exists.`);
			}
		});
	});
}

function createDir(dirPath) {
	return new Promise((resolve, reject) => {
		fs.mkdir(dirPath, err => {
			if (err) {
				reject(`ERR>>> Failed to create a folder '${dirPath}'`);
			} else {
				resolve();
			}
		});
	});
}

function createFiles(blocksPath, blockName) {
	const promises = [];
	Object.keys(fileSources).forEach(ext => {
		const fileSource = fileSources[ext].replace(/\{blockName}/g, blockName);
		const filename = `${blockName}.${ext}`;
		const filePath = path.join(blocksPath, filename);

		promises.push(
				new Promise((resolve, reject) => {
					fs.writeFile(filePath, fileSource, 'utf8', err => {
						if (err) {
							reject(`ERR>>> Failed to create a file '${filePath}'`);
						} else {
							resolve();
						}
					});
				})
		);
	});

	return Promise.all(promises);
}

function getFiles(blockPath) {
	return new Promise((resolve, reject) => {
		fs.readdir(blockPath, (err, files) => {
			if (err) {
				reject(`ERR>>> Failed to get a file list from a folder '${blockPath}'`);
			} else {
				resolve(files);
			}
		});
	});
}

function printErrorMessage(errText) {
	console.log(errText);
	rl.close();
}

// //////////////////////////////////////////////////////////////////////////

function initMakeBlock(candidateBlockName) {
	const blockNames = candidateBlockName.trim().split(/\s+/);

	const makeBlock = blockName => {
		const blockPath = path.join(BLOCKS_DIR, blockName);

		return validateBlockName(blockName)
			.then(() => directoryExist(blockPath, blockName))
			.then(() => createDir(blockPath))
			.then(() => createFiles(blockPath, blockName))
			.then(() => getFiles(blockPath))
			.then(files => {
				const line = '-'.repeat(48 + blockName.length);
				console.log(line);
				console.log(`The block has just been created in 'app/blocks/${blockName}'`);
				console.log(line);

				// Displays a list of files created
				files.forEach(file => console.log(file));

				rl.close();
			});
	};

	if (blockNames.length === 1) {
		return makeBlock(blockNames[0]);
	}

	const promises = blockNames.map(name => makeBlock(name));
	return Promise.all(promises);
}


// //////////////////////////////////////////////////////////////////////////
//
// Start here
//

// Command line arguments
const blockNameFromCli = process.argv
		.slice(2)
		// join all arguments to one string (to simplify the capture user input errors)
		.join(' ');

// If the user pass the name of the block in the command-line options
// that create a block. Otherwise - activates interactive mode
if (blockNameFromCli !== '') {
	initMakeBlock(blockNameFromCli).catch(printErrorMessage);
} else {
	rl.setPrompt('Block(s) name: ');
	rl.prompt();
	rl.on('line', (line) => {
		initMakeBlock(line).catch(printErrorMessage);
	});
}