index.js

var path = require('path'),
    pick = require('lodash.pick'),
    configModule = require('./lib/config'),
    detect = require('./lib/detect'),
    run = require('./lib/run'),
    createProfiles = require('./lib/create_profiles');

/**
 * Check the configuration and prepare a launcher function.
 * If there's no config ready, detect available browsers first.
 * Finally, pass a launcher function to the callback.
 * @param {String}   [configFile] Path to a configuration file
 * @param {Function} callback     Callback function
 */
function getLauncher(configFile, callback) {
    if (typeof configFile === 'function') {
        callback = configFile;
        configFile = configModule.defaultConfigFile;
    }

    configModule.read(configFile, function (err, config) {
        if (!config) {
            getLauncher.update(configFile, function (err, config) {
                if (err) {
                    callback(err);
                } else {
                    callback(null, wrap(config));
                }
            });
        } else {
            callback(null, wrap(config));
        }
    });

    function wrap(config) {
        var res = launch.bind(null, config);

        res.browsers = config.browsers;

        return res;
    }

    function launch(config, uri, options, callback) {
        if (typeof options === 'string') {
            options = {
                browser: options
            };
        }

        options = options || {};

        var version = options.version || options.browser.split('/')[1] || '*',
            name = options.browser.toLowerCase().split('/')[0],
            runner = run(config, name, version);

        if (!runner) {
            // update the list of available browsers and retry
            getLauncher.update(configFile, function (err, config) {
                if (!( runner = run(config, name, version) )) {
                    return callback(name + ' is not installed in your system.');
                }

                runner(uri, options, callback);
            });
        } else {
            runner(uri, options, callback);
        }
    }
}

/**
 * Detect available browsers
 * @param {Function} callback Callback function
 */
getLauncher.detect = function (callback) {
    detect(function (browsers) {
        callback(browsers.map(function (browser) {
            return pick(browser, ['name', 'version', 'type', 'command']);
        }));
    });
};

/**
 * Update the browsers cache and create new profiles if necessary
 * @param {String}   configFile Path to the configuration file
 * @param {Function} callback  Callback function
 */
getLauncher.update = function (configFile, callback) {
    if (typeof configFile === 'function') {
        callback = configFile;
        configFile = configModule.defaultConfigFile;
    }

    detect(function (browsers) {
        createProfiles(browsers, path.dirname(configFile), function (err) {
            if (err) {
                return callback(err);
            }

            var config = {
                browsers: browsers
            };

            configModule.write(configFile, config, function (err) {
                if (err) {
                    callback(err);
                } else {
                    callback(null, config);
                }
            });
        });
    });
};

module.exports = getLauncher;