/**
 * Copyright (c) 2014-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

var regeneratorRuntime = (function (exports) {
    "use strict";

    var Op = Object.prototype;
    var hasOwn = Op.hasOwnProperty;
    var undefined; // More compressible than void 0.
    var $Symbol = typeof Symbol === "function" ? Symbol : {};
    var iteratorSymbol = $Symbol.iterator || "@@iterator";
    var asyncIteratorSymbol = $Symbol.asyncIterator || "@@asyncIterator";
    var toStringTagSymbol = $Symbol.toStringTag || "@@toStringTag";

    function wrap(innerFn, outerFn, self, tryLocsList) {
        // If outerFn provided and outerFn.prototype is a Generator, then outerFn.prototype instanceof Generator.
        var protoGenerator = outerFn && outerFn.prototype instanceof Generator ? outerFn : Generator;
        var generator = Object.create(protoGenerator.prototype);
        var context = new Context(tryLocsList || []);

        // The ._invoke method unifies the implementations of the .next,
        // .throw, and .return methods.
        generator._invoke = makeInvokeMethod(innerFn, self, context);

        return generator;
    }
    exports.wrap = wrap;

    function tryCatch(fn, obj, arg) {
        try {
            return { type: "normal", arg: fn.call(obj, arg) };
        } catch (err) {
            return { type: "throw", arg: err };
        }
    }

    var GenStateSuspendedStart = "suspendedStart";
    var GenStateSuspendedYield = "suspendedYield";
    var GenStateExecuting = "executing";
    var GenStateCompleted = "completed";

    var ContinueSentinel = {};

    function Generator() {}
    function GeneratorFunction() {}
    function GeneratorFunctionPrototype() {}

    // This is a polyfill for %IteratorPrototype% for environments that
    // don't natively support it.
    var IteratorPrototype = {};
    IteratorPrototype[iteratorSymbol] = function () {
        return this;
    };

    var getProto = Object.getPrototypeOf;
    var NativeIteratorPrototype = getProto && getProto(getProto(values([])));
    if (NativeIteratorPrototype &&
        NativeIteratorPrototype !== Op &&
        hasOwn.call(NativeIteratorPrototype, iteratorSymbol)) {
        // This environment has a native %IteratorPrototype%; use it instead
        // of the polyfill.
        IteratorPrototype = NativeIteratorPrototype;
    }

    var Gp = GeneratorFunctionPrototype.prototype =
        Generator.prototype = Object.create(IteratorPrototype);
    GeneratorFunction.prototype = Gp.constructor = GeneratorFunctionPrototype;
    GeneratorFunctionPrototype.constructor = GeneratorFunction;
    GeneratorFunctionPrototype[toStringTagSymbol] =
        GeneratorFunction.displayName = "GeneratorFunction";

    // Helper for defining the .next, .throw, and .return methods of the
    // Iterator interface in terms of a single ._invoke method.
    function defineIteratorMethods(prototype) {
        ["next", "throw", "return"].forEach(function(method) {
            prototype[method] = function(arg) {
                return this._invoke(method, arg);
            };
        });
    }

    exports.isGeneratorFunction = function(genFun) {
        var ctor = typeof genFun === "function" && genFun.constructor;
        return ctor
            ? ctor === GeneratorFunction ||
            // For the native GeneratorFunction constructor, the best we can
            // do is to check its .name property.
            (ctor.displayName || ctor.name) === "GeneratorFunction"
            : false;
    };

    exports.mark = function(genFun) {
        if (Object.setPrototypeOf) {
            Object.setPrototypeOf(genFun, GeneratorFunctionPrototype);
        } else {
            genFun.__proto__ = GeneratorFunctionPrototype;
            if (!(toStringTagSymbol in genFun)) {
                genFun[toStringTagSymbol] = "GeneratorFunction";
            }
        }
        genFun.prototype = Object.create(Gp);
        return genFun;
    };

    // Within the body of any async function, `await x` is transformed to
    // `yield regeneratorRuntime.awrap(x)`, so that the runtime can test
    // `hasOwn.call(value, "__await")` to determine if the yielded value is
    // meant to be awaited.
    exports.awrap = function(arg) {
        return { __await: arg };
    };

    function AsyncIterator(generator) {
        function invoke(method, arg, resolve, reject) {
            var record = tryCatch(generator[method], generator, arg);
            if (record.type === "throw") {
                reject(record.arg);
            } else {
                var result = record.arg;
                var value = result.value;
                if (value &&
                    typeof value === "object" &&
                    hasOwn.call(value, "__await")) {
                    return Promise.resolve(value.__await).then(function(value) {
                        invoke("next", value, resolve, reject);
                    }, function(err) {
                        invoke("throw", err, resolve, reject);
                    });
                }

                return Promise.resolve(value).then(function(unwrapped) {
                    // When a yielded Promise is resolved, its final value becomes
                    // the .value of the Promise<{value,done}> result for the
                    // current iteration.
                    result.value = unwrapped;
                    resolve(result);
                }, function(error) {
                    // If a rejected Promise was yielded, throw the rejection back
                    // into the async generator function so it can be handled there.
                    return invoke("throw", error, resolve, reject);
                });
            }
        }

        var previousPromise;

        function enqueue(method, arg) {
            function callInvokeWithMethodAndArg() {
                return new Promise(function(resolve, reject) {
                    invoke(method, arg, resolve, reject);
                });
            }

            return previousPromise =
                previousPromise ? previousPromise.then(
                    callInvokeWithMethodAndArg,
                    callInvokeWithMethodAndArg
                ) : callInvokeWithMethodAndArg();
        }
        this._invoke = enqueue;
    }

    defineIteratorMethods(AsyncIterator.prototype);
    AsyncIterator.prototype[asyncIteratorSymbol] = function () {
        return this;
    };
    exports.AsyncIterator = AsyncIterator;

    // Note that simple async functions are implemented on top of
    // AsyncIterator objects; they just return a Promise for the value of
    // the final result produced by the iterator.
    exports.async = function(innerFn, outerFn, self, tryLocsList) {
        var iter = new AsyncIterator(
            wrap(innerFn, outerFn, self, tryLocsList)
        );

        return exports.isGeneratorFunction(outerFn)
            ? iter // If outerFn is a generator, return the full iterator.
            : iter.next().then(function(result) {
                return result.done ? result.value : iter.next();
            });
    };

    function makeInvokeMethod(innerFn, self, context) {
        var state = GenStateSuspendedStart;

        return function invoke(method, arg) {
            if (state === GenStateExecuting) {
                throw new Error("Generator is already running");
            }

            if (state === GenStateCompleted) {
                if (method === "throw") {
                    throw arg;
                }

                // Be forgiving, per 25.3.3.3.3 of the spec:
                // https://people.mozilla.org/~jorendorff/es6-draft.html#sec-generatorresume
                return doneResult();
            }

            context.method = method;
            context.arg = arg;

            while (true) {
                var delegate = context.delegate;
                if (delegate) {
                    var delegateResult = maybeInvokeDelegate(delegate, context);
                    if (delegateResult) {
                        if (delegateResult === ContinueSentinel) continue;
                        return delegateResult;
                    }
                }

                if (context.method === "next") {
                    // Setting context._sent for legacy support of Babel's
                    // function.sent implementation.
                    context.sent = context._sent = context.arg;

                } else if (context.method === "throw") {
                    if (state === GenStateSuspendedStart) {
                        state = GenStateCompleted;
                        throw context.arg;
                    }

                    context.dispatchException(context.arg);

                } else if (context.method === "return") {
                    context.abrupt("return", context.arg);
                }

                state = GenStateExecuting;

                var record = tryCatch(innerFn, self, context);
                if (record.type === "normal") {
                    // If an exception is thrown from innerFn, we leave state ===
                    // GenStateExecuting and loop back for another invocation.
                    state = context.done
                        ? GenStateCompleted
                        : GenStateSuspendedYield;

                    if (record.arg === ContinueSentinel) {
                        continue;
                    }

                    return {
                        value: record.arg,
                        done: context.done
                    };

                } else if (record.type === "throw") {
                    state = GenStateCompleted;
                    context.method = "throw";
                    context.arg = record.arg;
                }
            }
        };
    }

    function maybeInvokeDelegate(delegate, context) {
        var method = delegate.iterator[context.method];
        if (method === undefined) {
            context.delegate = null;

            if (context.method === "throw") {
                if (delegate.iterator.return) {
                    context.method = "return";
                    context.arg = undefined;
                    maybeInvokeDelegate(delegate, context);

                    if (context.method === "throw") {
                        return ContinueSentinel;
                    }
                }

                context.method = "throw";
                context.arg = new TypeError(
                    "The iterator does not provide a 'throw' method");
            }

            return ContinueSentinel;
        }

        var record = tryCatch(method, delegate.iterator, context.arg);

        if (record.type === "throw") {
            context.method = "throw";
            context.arg = record.arg;
            context.delegate = null;
            return ContinueSentinel;
        }

        var info = record.arg;

        if (! info) {
            context.method = "throw";
            context.arg = new TypeError("iterator result is not an object");
            context.delegate = null;
            return ContinueSentinel;
        }

        if (info.done) {
            context[delegate.resultName] = info.value;

            context.next = delegate.nextLoc;

            if (context.method !== "return") {
                context.method = "next";
                context.arg = undefined;
            }

        } else {
            // Re-yield the result returned by the delegate method.
            return info;
        }

        // The delegate iterator is finished, so forget it and continue with
        // the outer generator.
        context.delegate = null;
        return ContinueSentinel;
    }

    // Define Generator.prototype.{next,throw,return} in terms of the
    // unified ._invoke helper method.
    defineIteratorMethods(Gp);

    Gp[toStringTagSymbol] = "Generator";
    Gp[iteratorSymbol] = function() {
        return this;
    };

    Gp.toString = function() {
        return "[object Generator]";
    };

    function pushTryEntry(locs) {
        var entry = { tryLoc: locs[0] };

        if (1 in locs) {
            entry.catchLoc = locs[1];
        }

        if (2 in locs) {
            entry.finallyLoc = locs[2];
            entry.afterLoc = locs[3];
        }

        this.tryEntries.push(entry);
    }

    function resetTryEntry(entry) {
        var record = entry.completion || {};
        record.type = "normal";
        delete record.arg;
        entry.completion = record;
    }

    function Context(tryLocsList) {
        this.tryEntries = [{ tryLoc: "root" }];
        tryLocsList.forEach(pushTryEntry, this);
        this.reset(true);
    }

    exports.keys = function(object) {
        var keys = [];
        for (var key in object) {
            keys.push(key);
        }
        keys.reverse();
        return function next() {
            while (keys.length) {
                var key = keys.pop();
                if (key in object) {
                    next.value = key;
                    next.done = false;
                    return next;
                }
            }

            next.done = true;
            return next;
        };
    };

    function values(iterable) {
        if (iterable) {
            var iteratorMethod = iterable[iteratorSymbol];
            if (iteratorMethod) {
                return iteratorMethod.call(iterable);
            }

            if (typeof iterable.next === "function") {
                return iterable;
            }

            if (!isNaN(iterable.length)) {
                var i = -1, next = function next() {
                    while (++i < iterable.length) {
                        if (hasOwn.call(iterable, i)) {
                            next.value = iterable[i];
                            next.done = false;
                            return next;
                        }
                    }

                    next.value = undefined;
                    next.done = true;

                    return next;
                };

                return next.next = next;
            }
        }

        // Return an iterator with no values.
        return { next: doneResult };
    }
    exports.values = values;

    function doneResult() {
        return { value: undefined, done: true };
    }

    Context.prototype = {
        constructor: Context,

        reset: function(skipTempReset) {
            this.prev = 0;
            this.next = 0;
            this.sent = this._sent = undefined;
            this.done = false;
            this.delegate = null;

            this.method = "next";
            this.arg = undefined;

            this.tryEntries.forEach(resetTryEntry);

            if (!skipTempReset) {
                for (var name in this) {
                    // Not sure about the optimal order of these conditions:
                    if (name.charAt(0) === "t" &&
                        hasOwn.call(this, name) &&
                        !isNaN(+name.slice(1))) {
                        this[name] = undefined;
                    }
                }
            }
        },

        stop: function() {
            this.done = true;

            var rootEntry = this.tryEntries[0];
            var rootRecord = rootEntry.completion;
            if (rootRecord.type === "throw") {
                throw rootRecord.arg;
            }

            return this.rval;
        },

        dispatchException: function(exception) {
            if (this.done) {
                throw exception;
            }

            var context = this;
            function handle(loc, caught) {
                record.type = "throw";
                record.arg = exception;
                context.next = loc;

                if (caught) {
                    context.method = "next";
                    context.arg = undefined;
                }

                return !! caught;
            }

            for (var i = this.tryEntries.length - 1; i >= 0; --i) {
                var entry = this.tryEntries[i];
                var record = entry.completion;

                if (entry.tryLoc === "root") {
                    return handle("end");
                }

                if (entry.tryLoc <= this.prev) {
                    var hasCatch = hasOwn.call(entry, "catchLoc");
                    var hasFinally = hasOwn.call(entry, "finallyLoc");

                    if (hasCatch && hasFinally) {
                        if (this.prev < entry.catchLoc) {
                            return handle(entry.catchLoc, true);
                        } else if (this.prev < entry.finallyLoc) {
                            return handle(entry.finallyLoc);
                        }

                    } else if (hasCatch) {
                        if (this.prev < entry.catchLoc) {
                            return handle(entry.catchLoc, true);
                        }

                    } else if (hasFinally) {
                        if (this.prev < entry.finallyLoc) {
                            return handle(entry.finallyLoc);
                        }

                    } else {
                        throw new Error("try statement without catch or finally");
                    }
                }
            }
        },

        abrupt: function(type, arg) {
            for (var i = this.tryEntries.length - 1; i >= 0; --i) {
                var entry = this.tryEntries[i];
                if (entry.tryLoc <= this.prev &&
                    hasOwn.call(entry, "finallyLoc") &&
                    this.prev < entry.finallyLoc) {
                    var finallyEntry = entry;
                    break;
                }
            }

            if (finallyEntry &&
                (type === "break" ||
                    type === "continue") &&
                finallyEntry.tryLoc <= arg &&
                arg <= finallyEntry.finallyLoc) {
                finallyEntry = null;
            }

            var record = finallyEntry ? finallyEntry.completion : {};
            record.type = type;
            record.arg = arg;

            if (finallyEntry) {
                this.method = "next";
                this.next = finallyEntry.finallyLoc;
                return ContinueSentinel;
            }

            return this.complete(record);
        },

        complete: function(record, afterLoc) {
            if (record.type === "throw") {
                throw record.arg;
            }

            if (record.type === "break" ||
                record.type === "continue") {
                this.next = record.arg;
            } else if (record.type === "return") {
                this.rval = this.arg = record.arg;
                this.method = "return";
                this.next = "end";
            } else if (record.type === "normal" && afterLoc) {
                this.next = afterLoc;
            }

            return ContinueSentinel;
        },

        finish: function(finallyLoc) {
            for (var i = this.tryEntries.length - 1; i >= 0; --i) {
                var entry = this.tryEntries[i];
                if (entry.finallyLoc === finallyLoc) {
                    this.complete(entry.completion, entry.afterLoc);
                    resetTryEntry(entry);
                    return ContinueSentinel;
                }
            }
        },

        "catch": function(tryLoc) {
            for (var i = this.tryEntries.length - 1; i >= 0; --i) {
                var entry = this.tryEntries[i];
                if (entry.tryLoc === tryLoc) {
                    var record = entry.completion;
                    if (record.type === "throw") {
                        var thrown = record.arg;
                        resetTryEntry(entry);
                    }
                    return thrown;
                }
            }

            throw new Error("illegal catch attempt");
        },

        delegateYield: function(iterable, resultName, nextLoc) {
            this.delegate = {
                iterator: values(iterable),
                resultName: resultName,
                nextLoc: nextLoc
            };

            if (this.method === "next") {
                // Deliberately forget the last sent value so that we don't
                // accidentally pass it on to the delegate.
                this.arg = undefined;
            }

            return ContinueSentinel;
        }
    };

    return exports;

}(
    typeof module === "object" ? module.exports : {}
));