'use strict';

var index = require('../node_modules/ms/index.js');

var common;
var hasRequiredCommon;

function requireCommon () {
	if (hasRequiredCommon) return common;
	hasRequiredCommon = 1;
	/**
	 * This is the common logic for both the Node.js and web browser
	 * implementations of `debug()`.
	 */

	function setup(env) {
		createDebug.debug = createDebug;
		createDebug.default = createDebug;
		createDebug.coerce = coerce;
		createDebug.disable = disable;
		createDebug.enable = enable;
		createDebug.enabled = enabled;
		createDebug.humanize = index.__require();
		createDebug.destroy = destroy;

		Object.keys(env).forEach(key => {
			createDebug[key] = env[key];
		});

		/**
		* The currently active debug mode names, and names to skip.
		*/

		createDebug.names = [];
		createDebug.skips = [];

		/**
		* Map of special "%n" handling functions, for the debug "format" argument.
		*
		* Valid key names are a single, lower or upper-case letter, i.e. "n" and "N".
		*/
		createDebug.formatters = {};

		/**
		* Selects a color for a debug namespace
		* @param {String} namespace The namespace string for the debug instance to be colored
		* @return {Number|String} An ANSI color code for the given namespace
		* @api private
		*/
		function selectColor(namespace) {
			let hash = 0;

			for (let i = 0; i < namespace.length; i++) {
				hash = ((hash << 5) - hash) + namespace.charCodeAt(i);
				hash |= 0; // Convert to 32bit integer
			}

			return createDebug.colors[Math.abs(hash) % createDebug.colors.length];
		}
		createDebug.selectColor = selectColor;

		/**
		* Create a debugger with the given `namespace`.
		*
		* @param {String} namespace
		* @return {Function}
		* @api public
		*/
		function createDebug(namespace) {
			let prevTime;
			let enableOverride = null;
			let namespacesCache;
			let enabledCache;

			function debug(...args) {
				// Disabled?
				if (!debug.enabled) {
					return;
				}

				const self = debug;

				// Set `diff` timestamp
				const curr = Number(new Date());
				const ms = curr - (prevTime || curr);
				self.diff = ms;
				self.prev = prevTime;
				self.curr = curr;
				prevTime = curr;

				args[0] = createDebug.coerce(args[0]);

				if (typeof args[0] !== 'string') {
					// Anything else let's inspect with %O
					args.unshift('%O');
				}

				// Apply any `formatters` transformations
				let index = 0;
				args[0] = args[0].replace(/%([a-zA-Z%])/g, (match, format) => {
					// If we encounter an escaped % then don't increase the array index
					if (match === '%%') {
						return '%';
					}
					index++;
					const formatter = createDebug.formatters[format];
					if (typeof formatter === 'function') {
						const val = args[index];
						match = formatter.call(self, val);

						// Now we need to remove `args[index]` since it's inlined in the `format`
						args.splice(index, 1);
						index--;
					}
					return match;
				});

				// Apply env-specific formatting (colors, etc.)
				createDebug.formatArgs.call(self, args);

				const logFn = self.log || createDebug.log;
				logFn.apply(self, args);
			}

			debug.namespace = namespace;
			debug.useColors = createDebug.useColors();
			debug.color = createDebug.selectColor(namespace);
			debug.extend = extend;
			debug.destroy = createDebug.destroy; // XXX Temporary. Will be removed in the next major release.

			Object.defineProperty(debug, 'enabled', {
				enumerable: true,
				configurable: false,
				get: () => {
					if (enableOverride !== null) {
						return enableOverride;
					}
					if (namespacesCache !== createDebug.namespaces) {
						namespacesCache = createDebug.namespaces;
						enabledCache = createDebug.enabled(namespace);
					}

					return enabledCache;
				},
				set: v => {
					enableOverride = v;
				}
			});

			// Env-specific initialization logic for debug instances
			if (typeof createDebug.init === 'function') {
				createDebug.init(debug);
			}

			return debug;
		}

		function extend(namespace, delimiter) {
			const newDebug = createDebug(this.namespace + (typeof delimiter === 'undefined' ? ':' : delimiter) + namespace);
			newDebug.log = this.log;
			return newDebug;
		}

		/**
		* Enables a debug mode by namespaces. This can include modes
		* separated by a colon and wildcards.
		*
		* @param {String} namespaces
		* @api public
		*/
		function enable(namespaces) {
			createDebug.save(namespaces);
			createDebug.namespaces = namespaces;

			createDebug.names = [];
			createDebug.skips = [];

			let i;
			const split = (typeof namespaces === 'string' ? namespaces : '').split(/[\s,]+/);
			const len = split.length;

			for (i = 0; i < len; i++) {
				if (!split[i]) {
					// ignore empty strings
					continue;
				}

				namespaces = split[i].replace(/\*/g, '.*?');

				if (namespaces[0] === '-') {
					createDebug.skips.push(new RegExp('^' + namespaces.slice(1) + '$'));
				} else {
					createDebug.names.push(new RegExp('^' + namespaces + '$'));
				}
			}
		}

		/**
		* Disable debug output.
		*
		* @return {String} namespaces
		* @api public
		*/
		function disable() {
			const namespaces = [
				...createDebug.names.map(toNamespace),
				...createDebug.skips.map(toNamespace).map(namespace => '-' + namespace)
			].join(',');
			createDebug.enable('');
			return namespaces;
		}

		/**
		* Returns true if the given mode name is enabled, false otherwise.
		*
		* @param {String} name
		* @return {Boolean}
		* @api public
		*/
		function enabled(name) {
			if (name[name.length - 1] === '*') {
				return true;
			}

			let i;
			let len;

			for (i = 0, len = createDebug.skips.length; i < len; i++) {
				if (createDebug.skips[i].test(name)) {
					return false;
				}
			}

			for (i = 0, len = createDebug.names.length; i < len; i++) {
				if (createDebug.names[i].test(name)) {
					return true;
				}
			}

			return false;
		}

		/**
		* Convert regexp to namespace
		*
		* @param {RegExp} regxep
		* @return {String} namespace
		* @api private
		*/
		function toNamespace(regexp) {
			return regexp.toString()
				.substring(2, regexp.toString().length - 2)
				.replace(/\.\*\?$/, '*');
		}

		/**
		* Coerce `val`.
		*
		* @param {Mixed} val
		* @return {Mixed}
		* @api private
		*/
		function coerce(val) {
			if (val instanceof Error) {
				return val.stack || val.message;
			}
			return val;
		}

		/**
		* XXX DO NOT USE. This is a temporary stub function.
		* XXX It WILL be removed in the next major release.
		*/
		function destroy() {
			console.warn('Instance method `debug.destroy()` is deprecated and no longer does anything. It will be removed in the next major version of `debug`.');
		}

		createDebug.enable(createDebug.load());

		return createDebug;
	}

	common = setup;
	return common;
}

exports.__require = requireCommon;
