"use strict";
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const Deferred = require("./Deferred");
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const errors = require("./errors");
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function fbind(fn, ctx) {
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return function bound() {
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return fn.apply(ctx, arguments);
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};
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}
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/**
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* Wraps a users request for a resource
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* Basically a promise mashed in with a timeout
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* @private
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*/
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class ResourceRequest extends Deferred {
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/**
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* [constructor description]
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* @param {Number} ttl timeout
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*/
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constructor(ttl, Promise) {
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super(Promise);
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this._creationTimestamp = Date.now();
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this._timeout = null;
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if (ttl !== undefined) {
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this.setTimeout(ttl);
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}
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}
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setTimeout(delay) {
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if (this._state !== ResourceRequest.PENDING) {
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return;
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}
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const ttl = parseInt(delay, 10);
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if (isNaN(ttl) || ttl <= 0) {
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throw new Error("delay must be a positive int");
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}
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const age = Date.now() - this._creationTimestamp;
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if (this._timeout) {
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this.removeTimeout();
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}
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this._timeout = setTimeout(
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fbind(this._fireTimeout, this),
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Math.max(ttl - age, 0)
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);
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}
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removeTimeout() {
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if (this._timeout) {
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clearTimeout(this._timeout);
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}
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this._timeout = null;
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}
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_fireTimeout() {
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this.reject(new errors.TimeoutError("ResourceRequest timed out"));
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}
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reject(reason) {
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this.removeTimeout();
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super.reject(reason);
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}
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resolve(value) {
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this.removeTimeout();
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super.resolve(value);
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}
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}
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module.exports = ResourceRequest;
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