/**
 * This is the web browser implementation of `debug()`.
 *
 * Expose `debug()` as the module.
 */

exports = module.exports = require('./debug');
exports.log = log;
exports.formatArgs = formatArgs;
exports.save = save;
exports.load = load;
exports.useColors = useColors;
exports.storage = 'undefined' != typeof chrome
 && 'undefined' != typeof chrome.storage
 ? chrome.storage.local
 : localstorage();

/**
 * Colors.
 */

exports.colors = [
 'lightseagreen',
 'forestgreen',
 'goldenrod',
 'dodgerblue',
 'darkorchid',
 'crimson'
];

/**
 * Currently only WebKit-based Web Inspectors, Firefox >= v31,
 * and the Firebug extension (any Firefox version) are known
 * to support "%c" CSS customizations.
 *
 * TODO: add a `localStorage` variable to explicitly enable/disable colors
 */

function useColors() {
 // NB: In an Electron preload script, document will be defined but not fully
 // initialized. Since we know we're in Chrome, we'll just detect this case
 // explicitly
 if (typeof window !== 'undefined' && window.process && window.process.type === 'renderer') {
 return true;
 }

 // is webkit? http://stackoverflow.com/a/16459606/376773
 // document is undefined in react-native: https://github.com/facebook/react-native/pull/1632
 return (typeof document !== 'undefined' && document.documentElement && document.documentElement.style && document.documentElement.style.WebkitAppearance) ||
 // is firebug? http://stackoverflow.com/a/398120/376773
 (typeof window !== 'undefined' && window.console && (window.console.firebug || (window.console.exception && window.console.table))) ||
 // is firefox >= v31?
 // https://developer.mozilla.org/en-US/docs/Tools/Web_Console#Styling_messages
 (typeof navigator !== 'undefined' && navigator.userAgent && navigator.userAgent.toLowerCase().match(/firefox\/(\d+)/) && parseInt(RegExp.1ドル, 10) >= 31) ||
 // double check webkit in userAgent just in case we are in a worker
 (typeof navigator !== 'undefined' && navigator.userAgent && navigator.userAgent.toLowerCase().match(/applewebkit\/(\d+)/));
}

/**
 * Map %j to `JSON.stringify()`, since no Web Inspectors do that by default.
 */

exports.formatters.j = function(v) {
 try {
 return JSON.stringify(v);
 } catch (err) {
 return '[UnexpectedJSONParseError]: ' + err.message;
 }
};


/**
 * Colorize log arguments if enabled.
 *
 * @api public
 */

function formatArgs(args) {
 var useColors = this.useColors;

 args[0] = (useColors ? '%c' : '')
 + this.namespace
 + (useColors ? ' %c' : '')
 + args[0]
 + (useColors ? '%c ' : '')
 + '+' + exports.humanize(this.diff);

 if (!useColors) return;

 var c = 'color: ' + this.color;
 args.splice(1, 0, c, 'color: inherit')

 // the final "%c" is somewhat tricky, because there could be other
 // arguments passed either before or after the %c, so we need to
 // figure out the correct index to insert the CSS into
 var index = 0;
 var lastC = 0;
 args[0].replace(/%[a-zA-Z%]/g, function(match) {
 if ('%%' === match) return;
 index++;
 if ('%c' === match) {
 // we only are interested in the *last* %c
 // (the user may have provided their own)
 lastC = index;
 }
 });

 args.splice(lastC, 0, c);
}

/**
 * Invokes `console.log()` when available.
 * No-op when `console.log` is not a "function".
 *
 * @api public
 */

function log() {
 // this hackery is required for IE8/9, where
 // the `console.log` function doesn't have 'apply'
 return 'object' === typeof console
 && console.log
 && Function.prototype.apply.call(console.log, console, arguments);
}

/**
 * Save `namespaces`.
 *
 * @param {String} namespaces
 * @api private
 */

function save(namespaces) {
 try {
 if (null == namespaces) {
 exports.storage.removeItem('debug');
 } else {
 exports.storage.debug = namespaces;
 }
 } catch(e) {}
}

/**
 * Load `namespaces`.
 *
 * @return {String} returns the previously persisted debug modes
 * @api private
 */

function load() {
 var r;
 try {
 r = exports.storage.debug;
 } catch(e) {}

 // If debug isn't set in LS, and we're in Electron, try to load $DEBUG
 if (!r && typeof process !== 'undefined' && 'env' in process) {
 r = process.env.DEBUG;
 }

 return r;
}

/**
 * Enable namespaces listed in `localStorage.debug` initially.
 */

exports.enable(load());

/**
 * Localstorage attempts to return the localstorage.
 *
 * This is necessary because safari throws
 * when a user disables cookies/localstorage
 * and you attempt to access it.
 *
 * @return {LocalStorage}
 * @api private
 */

function localstorage() {
 try {
 return window.localStorage;
 } catch (e) {}
}