import * as ejs from 'ejs';
import * as fs from 'fs';
import * as path from 'path';

/**
 * Renders a component from the code base.
 * @param file the filename/path of the file to render
 * @param values the values to use while templating
 */
export function render(file: string, values: { [key: string]: any }): string {
	file = file.endsWith('.ejs') ? file : file + '.ejs';
	const filepath: string = path.resolve(path.join(__dirname, '../views', file));

	// Check if file exists
	if (fs.existsSync(filepath)) {
		// Render file
		const body: string = fs.readFileSync(filepath).toString();

		// Add oreo library to values
		values.oreo = {
			render
		};

		return ejs.render(body, values);
	}

	return null;
}

export function getStaticFolder(): string {
	return path.resolve(path.join(__dirname, '../public'));
}

export function getViewFolder(): string {
	return path.resolve(path.join(__dirname, '../views'));
}

export function engine(filepath, data, callback) {
	filepath = path.resolve(path.join(__dirname, '../views', filepath.endsWith('.ejs') ? filepath : filepath + '.ejs'));

	fs.readFile(filepath, (err, contents) => {
		if (err)
			return callback(err, null);

		callback(null, ejs.render(contents), data);
	});
}