var Fiber = require('fibers');

function sleep(ms) {
	var fiber = Fiber.current;
	setTimeout(function() {
		fiber.run();
	}, ms);
	Fiber.yield();
}

Fiber(function() {
	console.log('wait... '   new Date);
	sleep(1000);
	console.log('ok... '   new Date);
}).run();
console.log('back in main');

var Fiber = require('fibers');

var inc = Fiber(function(start) {
	var total = start;
	while (true) {
		total  = Fiber.yield(total);
	}
});

for (var ii = inc.run(1); ii <= 10; ii = inc.run(1)) {
	console.log(ii);
}

var Fiber = require('fibers');

// Generator function. Returns a function which returns incrementing
// Fibonacci numbers with each call.
function Fibonacci() {
	// Create a new fiber which yields sequential Fibonacci numbers
	var fiber = Fiber(function() {
		Fiber.yield(0); // F(0) -> 0
		var prev = 0, curr = 1;
		while (true) {
			Fiber.yield(curr);
			var tmp = prev   curr;
			prev = curr;
			curr = tmp;
		}
	});
	// Return a bound handle to `run` on this fiber
	return fiber.run.bind(fiber);
}

// Initialize a new Fibonacci sequence and iterate up to 1597
var seq = Fibonacci();
for (var ii = seq(); ii <= 1597; ii = seq()) {
	console.log(ii);
}

var Fiber = require('fibers');

var fn = Fiber(function() {
	console.log('async work here...');
	Fiber.yield();
	console.log('still working...');
	Fiber.yield();
	console.log('just a little bit more...');
	Fiber.yield();
	throw new Error('oh crap!');
});

try {
	while (true) {
		fn.run();
	}
} catch(e) {
	console.log('safely caught that error!');
	console.log(e.stack);
}
console.log('done!');

var Future = require('fibers/future');
var fs = Future.wrap(require('fs'));

Future.task(function() {
	// Get a list of files in the directory
	var fileNames = fs.readdirFuture('.').wait();
	console.log('Found '  fileNames.length  ' files');

	// Stat each file
	var stats = [];
	for (var ii = 0; ii < fileNames.length;   ii) {
		stats.push(fs.statFuture(fileNames[ii]));
	}
	stats.map(function(f) {
		f.wait()
	});

	// Print file size
	for (var ii = 0; ii < fileNames.length;   ii) {
		console.log(fileNames[ii]  ': '  stats[ii].get().size);
	}
}).detach();

var Future = require('fibers/future'), wait = Future.wait;

// This function returns a future which resolves after a timeout. This
// demonstrates manually resolving futures.
function sleep(ms) {
	var future = new Future;
	setTimeout(function() {
		future.return();
	}, ms);
	return future;
}

// You can create functions which automatically run in their own fiber and
// return futures that resolve when the fiber returns (this probably sounds
// confusing.. just play with it to understand).
var calcTimerDelta = function(ms) {
	var start = new Date;
	sleep(ms).wait();
	return new Date - start;
}.future(); // <-- important!

// And futures also include node-friendly callbacks if you don't want to use
// wait()
calcTimerDelta(2000).resolve(function(err, val) {
	console.log('Set timer for 2000ms, waited '  val  'ms');
});

/**
 * Instantiate a new Fiber. You may invoke this either as a function or as
 * a constructor; the behavior is the same.
 *
 * When run() is called on this fiber for the first time, `fn` will be
 * invoked as the first frame on a new stack. Execution will continue on
 * this new stack until `fn` returns, or Fiber.yield() is called.
 *
 * After the function returns the fiber is reset to original state and
 * may be restarted with another call to run().
 */
function Fiber(fn) {
	[native code]
}

/**
 * `Fiber.current` will contain the currently-running Fiber. It will be
 * `undefined` if there is no fiber (i.e. the main stack of execution).
 *
 * See "Garbage Collection" for more information on responsible use of
 * `Fiber.current`.
 */
Fiber.current = undefined;

/**
 * `Fiber.yield()` will halt execution of the current fiber and return control
 * back to original caller of run(). If an argument is supplied to yield(),
 * run() will return that value.
 *
 * When run() is called again, yield() will return.
 *
 * Note that this function is a global to allow for correct garbage
 * collection. This results in no loss of functionality because it is only
 * valid to yield from the currently running fiber anyway.
 *
 * Note also that `yield` is a reserved word in Javascript. This is normally
 * not an issue, however some code linters may complain. Rest assured that it
 * will run fine now and in future versions of Javascript.
 */
Fiber.yield = function(param) {
	[native code]
}

/**
 * run() will start execution of this Fiber, or if it is currently yielding,
 * it will resume execution. If an argument is supplied, this argument will
 * be passed to the fiber, either as the first parameter to the main
 * function [if the fiber has not been started] or as the return value of
 * yield() [if the fiber is currently yielding].
 *
 * This function will return either the parameter passed to yield(), or the
 * returned value from the fiber's main function.
 */
Fiber.prototype.run = function(param) {
	[native code]
}

/**
 * reset() will terminate a running Fiber and restore it to its original
 * state, as if it had returned execution.
 *
 * This is accomplished by causing yield() to throw an exception, and any
 * futher calls to yield() will also throw an exception. This continues
 * until the fiber has completely unwound and returns.
 *
 * If the fiber returns a value it will be returned by reset().
 *
 * If the fiber is not running, reset() will have no effect.
 */
Fiber.prototype.reset = function() {
	[native code]
}

/**
 * throwInto() will cause a currently yielding fiber's yield() call to
 * throw instead of return gracefully. This can be useful for notifying a
 * fiber that you are no longer interested in its task, and that it should
 * give up.
 *
 * Note that if the fiber does not handle the exception it will continue to
 * bubble up and throwInto() will throw the exception right back at you.
 */
Fiber.prototype.throwInto = function(exception) {
	[native code]
}

/**
 * Returns a future-function which, when run, starts running the target
 * function and returns a future for the result.
 * 
 * Example usage: 
 * var funcy = function(arg) {
 *   return arg 1;
 * }.future();
 * 
 * funcy(1).wait(); // returns 2
 */
Function.prototype.future = function() { ... }

/**
 * Future object, instantiated with the new operator.
 */
function Future() {}

/**
 * Wrap a node-style async function to return a future in place of using a callback.
 * 
 * fn - the function or object to wrap
 * array - indicates that this callback will return more than 1 argument after `err`. For example,
 *         `child_process.exec()` returns [err, stdout, stderr]
 * suffix - appends a string to every method that was overridden, if you passed an object
 * 
 * Example usage: Future.wrap(asyncFunction)(arg1).wait()
 */
Future.wrap = function(fn, multi, suffix) { ... }

/**
 * Invoke a function that will be run in its own fiber context and return a future to its return
 * value.
 *
 * Example:
 * Future.task(function() {
 *   // You can safely `wait` on stuff here
 * }).detach();
 */
Future.task = function(fn) { ... }

/**
 * Wait on a series of futures and then return. If the futures throw an exception this function
 * /won't/ throw it back. You can get the value of the future by calling get() on it directly. If
 * you want to wait on a single future you're better off calling future.wait() on the instance.
 * 
 * Example usage: Future.wait(aFuture, anotherFuture)
 */
Future.wait = function(/* ... */) { ... }

/**
 * Return the value of this future. If the future hasn't resolved yet this will throw an error.
 */
Future.prototype.get = function() { ... }

/**
 * Mark this future as returned. All pending callbacks will be invoked immediately.
 * 
 * value - the value to return when get() or wait() is called.
 * 
 * Example usage: aFuture.return(value)
 */
Future.prototype.return = function(value) { ... }

/**
 * Throw from this future as returned. All pending callbacks will be invoked immediately.
 * Note that execution will continue normally after running this method, 
 * so make sure you exit appropriately after running throw()
 * 
 * error - the error to throw when get() or wait() is called.
 * 
 * Example usage: aFuture.throw(new Error("Something borked"))
 */
Future.prototype.throw = function(error) { ... }

/**
 * "detach" this future. Basically this is useful if you want to run a task in a future, you
 * aren't interested in its return value, but if it throws you don't want the exception to be
 * lost. If this fiber throws, an exception will be thrown to the event loop and node will
 * probably fall down.
 */
Future.prototype.detach = function() { ... }

/**
 * Returns whether or not this future has resolved yet.
 */
Future.prototype.isResolved = function() { ... }

/**
 * Returns a node-style function which will mark this future as resolved when called.
 * 
 * Example usage: 
 *   var errback = aFuture.resolver();
 *   asyncFunction(arg1, arg2, etc, errback)
 *   var result = aFuture.wait();
 */
Future.prototype.resolver = function() { ... }

/**
 * Waits for this future to resolve and then invokes a callback.
 *
 * If only one argument is passed it is a standard function(err, val){} errback.
 *
 * If two arguments are passed, the first argument is a future which will be thrown to in the case
 * of error, and the second is a function(val){} callback.
 */
Future.prototype.resolve = function(/* errback or future, callback */) { ... }

/**
 * Propogate results to another future.
 * 
 * Example usage: future1.proxy(future2) // future2 gets automatically resolved with however future1 resolves
 */
Future.prototype.proxy = function(future) { ... }

/**
 * Differs from its functional counterpart in that it actually resolves the future. Thus if the
 * future threw, future.wait() will throw.
 */
Future.prototype.wait = function() { ... }

/**
 * Support for converting a Future to and from ES6 Promises.
 */
Future.fromPromise = function(promise) { ... }
Future.prototype.promise = function() { ... }

var fiber = Fiber(function() {
	while (true) {
		try {
			Fiber.yield();
		} catch(e) {}
	}
});
fiber.run();

var fiber = Fiber(function() {
	var that = Fiber.current;
	Fiber.yield();
}
fiber.run();
fiber = undefined;