ractive/src/parse/converters/element/processDirective.js

Next-generation DOM manipulation

import parseJSON from 'utils/parseJSON';

// TODO clean this up, it's shocking
export default function ( tokens ) {
	var result, token, colonIndex, directiveName, directiveArgs, parsed;

	if ( typeof tokens === 'string' ) {
		if ( tokens.indexOf( ':' ) === -1 ) {
			return tokens.trim();
		}

		tokens = [ tokens ];
	}

	result = {};

	directiveName = [];
	directiveArgs = [];

	while ( tokens.length ) {
		token = tokens.shift();

		if ( typeof token === 'string' ) {
			colonIndex = token.indexOf( ':' );

			if ( colonIndex === -1 ) {
				directiveName.push( token );
			} else {

				// is the colon the first character?
				if ( colonIndex ) {
					// no
					directiveName.push( token.substr( 0, colonIndex ) );
				}

				// if there is anything after the colon in this token, treat
				// it as the first token of the directiveArgs fragment
				if ( token.length > colonIndex + 1 ) {
					directiveArgs[0] = token.substring( colonIndex + 1 );
				}

				break;
			}
		}

		else {
			directiveName.push( token );
		}
	}

	directiveArgs = directiveArgs.concat( tokens );

	if ( directiveArgs.length || typeof directiveName !== 'string' ) {
		result = {
			// TODO is this really necessary? just use the array
			n: ( directiveName.length === 1 && typeof directiveName[0] === 'string' ? directiveName[0] : directiveName )
		};

		if ( directiveArgs.length === 1 && typeof directiveArgs[0] === 'string' ) {
			parsed = parseJSON( '[' + directiveArgs[0] + ']' );
			result.a = parsed ? parsed.value : directiveArgs[0].trim();
		}

		else {
			result.d = directiveArgs;
		}
	} else {
		result = directiveName;
	}

	return result;
}