frisb/modularize

export default function ({input, deps, exports, type}) {
    deps = deps || [];

    let params = '';
    let rootParams = '';
    let es6Required = '';
    let amdRequired = '';
    let commonJSRequired = '';
    let returns = '';

    for (let i = 0; i < deps.length; i++) {
        let dependency = deps[i];

        if (typeof(dependency) === 'string') {
            let obj = {};
            obj[dependency] = dependency;
            dependency = obj;
        }

        for (let path in dependency) {
            let param = dependency[path];
            let sep = i < deps.length - 1 ? ', ' : '';

            es6Required += `import ${param} from '${path}';\n`;
            amdRequired += `'${path}'${sep}`;
            commonJSRequired += `\t\tvar ${param} = require('${path}');\n`;
            params += `${param}${sep}`;
            rootParams += `root.${param}${sep}`;
        }
    }

    if (exports) {
        switch (type) {
            case 'es6':
                returns = 'export default';
                break;

            case 'common':
                returns = 'module.exports =';
                break;

            default:
                returns = 'return';
                break;
        }
    }

    function content() {
        let output = '';
        let lines = input.replace(/\r\n/g, '\n').split('\n');
        let len = lines.length;

        for (let j = 0; j < len; j++) {
            output += `\t${lines[j]}\n`;
        }

        return output + (exports ? `\n\t${returns} ${exports};` : '');
    }

    function es6() {
        return `${es6Required}
${content()}`;
    }

    function amd() {
        return `define([${amdRequired}], function(${params}) {
${content()}
});`;
    }

    function commonjs() {
        return `${commonJSRequired}
${content()}`;
    }

    function umd() {
        return `(function(root, factory) {
    if (typeof(define) === 'function' && typeof(define.amd) !== 'undefined') {
        define([${amdRequired}], function(${params}) {
            ${exports ? 'return ' : ''}factory(${params});
        });
    }
    else if (typeof(module) !== 'undefined' && typeof(module.exports) !== 'undefined') {
${commonJSRequired}
        ${exports ? 'module.exports = ' : ''}factory(${params});
    }
    else {
        ${exports ? 'root.' + exports + ' = ' : ''}factory(${rootParams});
    }
})(this, function(${params}) {
${content()}
});`;
    }

    switch (type) {
        case 'es6': return es6();
        case 'amd': return amd();
        case 'common': return commonjs();
        default: return umd();
    }
}