// json2.js
// 2017-06-12
// Public Domain.
// NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK.
// USE YOUR OWN COPY. IT IS EXTREMELY UNWISE TO LOAD CODE FROM SERVERS YOU DO
// NOT CONTROL.
// This file creates a global JSON object containing two methods: stringify
// and parse. This file provides the ES5 JSON capability to ES3 systems.
// If a project might run on IE8 or earlier, then this file should be included.
// This file does nothing on ES5 systems.
// JSON.stringify(value, replacer, space)
// value any JavaScript value, usually an object or array.
// replacer an optional parameter that determines how object
// values are stringified for objects. It can be a
// function or an array of strings.
// space an optional parameter that specifies the indentation
// of nested structures. If it is omitted, the text will
// be packed without extra whitespace. If it is a number,
// it will specify the number of spaces to indent at each
// level. If it is a string (such as "\t" or " "),
// it contains the characters used to indent at each level.
// This method produces a JSON text from a JavaScript value.
// When an object value is found, if the object contains a toJSON
// method, its toJSON method will be called and the result will be
// stringified. A toJSON method does not serialize: it returns the
// value represented by the name/value pair that should be serialized,
// or undefined if nothing should be serialized. The toJSON method
// will be passed the key associated with the value, and this will be
// bound to the value.
// For example, this would serialize Dates as ISO strings.
// Date.prototype.toJSON = function (key) {
// function f(n) {
// // Format integers to have at least two digits.
// return (n < 10)
// ? "0" + n
// : n;
// }
// return this.getUTCFullYear() + "-" +
// f(this.getUTCMonth() + 1) + "-" +
// f(this.getUTCDate()) + "T" +
// f(this.getUTCHours()) + ":" +
// f(this.getUTCMinutes()) + ":" +
// f(this.getUTCSeconds()) + "Z";
// };
// You can provide an optional replacer method. It will be passed the
// key and value of each member, with this bound to the containing
// object. The value that is returned from your method will be
// serialized. If your method returns undefined, then the member will
// be excluded from the serialization.
// If the replacer parameter is an array of strings, then it will be
// used to select the members to be serialized. It filters the results
// such that only members with keys listed in the replacer array are
// stringified.
// Values that do not have JSON representations, such as undefined or
// functions, will not be serialized. Such values in objects will be
// dropped; in arrays they will be replaced with null. You can use
// a replacer function to replace those with JSON values.
// JSON.stringify(undefined) returns undefined.
// The optional space parameter produces a stringification of the
// value that is filled with line breaks and indentation to make it
// easier to read.
// If the space parameter is a non-empty string, then that string will
// be used for indentation. If the space parameter is a number, then
// the indentation will be that many spaces.
// Example:
// text = JSON.stringify(["e", {pluribus: "unum"}]);
// // text is '["e",{"pluribus":"unum"}]'
// text = JSON.stringify(["e", {pluribus: "unum"}], null, "\t");
// // text is '[\n\t"e",\n\t{\n\t\t"pluribus": "unum"\n\t}\n]'
// text = JSON.stringify([new Date()], function (key, value) {
// return this[key] instanceof Date
// ? "Date(" + this[key] + ")"
// : value;
// });
// // text is '["Date(---current time---)"]'
// JSON.parse(text, reviver)
// This method parses a JSON text to produce an object or array.
// It can throw a SyntaxError exception.
// The optional reviver parameter is a function that can filter and
// transform the results. It receives each of the keys and values,
// and its return value is used instead of the original value.
// If it returns what it received, then the structure is not modified.
// If it returns undefined then the member is deleted.
// Example:
// // Parse the text. Values that look like ISO date strings will
// // be converted to Date objects.
// myData = JSON.parse(text, function (key, value) {
// var a;
// if (typeof value === "string") {
// a =
// /^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2}(?:\.\d*)?)Z$/.exec(value);
// if (a) {
// return new Date(Date.UTC(
// +a[1], +a[2] - 1, +a[3], +a[4], +a[5], +a[6]
// ));
// }
// return value;
// }
// });
// myData = JSON.parse(
// "[\"Date(09/09/2001)\"]",
// function (key, value) {
// var d;
// if (
// typeof value === "string"
// && value.slice(0, 5) === "Date("
// && value.slice(-1) === ")"
// ) {
// d = new Date(value.slice(5, -1));
// if (d) {
// return d;
// }
// }
// return value;
// }
// );
// This is a reference implementation. You are free to copy, modify, or
// redistribute.
/*jslint
eval, for, this
*/
/*property
JSON, apply, call, charCodeAt, getUTCDate, getUTCFullYear, getUTCHours,
getUTCMinutes, getUTCMonth, getUTCSeconds, hasOwnProperty, join,
lastIndex, length, parse, prototype, push, replace, slice, stringify,
test, toJSON, toString, valueOf
*/
// Create a JSON object only if one does not already exist. We create the
// methods in a closure to avoid creating global variables.
if (typeof JSON !== "object") {
    JSON = {};
}
(function () {
    "use strict";
    var rx_one = /^[\],:{}\s]*$/;
    var rx_two = /\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g;
    var rx_three = /"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g;
    var rx_four = /(?:^|:|,)(?:\s*\[)+/g;
    var rx_escapable = /[\\"\u0000-\u001f\u007f-\u009f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g;
    var rx_dangerous = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g;

    function f(n) {
        // Format integers to have at least two digits.
        return (n < 10) ?
            "0" + n :
            n;
    }

    function this_value() {
        return this.valueOf();
    }
    if (typeof Date.prototype.toJSON !== "function") {
        Date.prototype.toJSON = function () {
            return isFinite(this.valueOf()) ?
                (
                    this.getUTCFullYear() +
                    "-" +
                    f(this.getUTCMonth() + 1) +
                    "-" +
                    f(this.getUTCDate()) +
                    "T" +
                    f(this.getUTCHours()) +
                    ":" +
                    f(this.getUTCMinutes()) +
                    ":" +
                    f(this.getUTCSeconds()) +
                    "Z"
                ) :
                null;
        };
        Boolean.prototype.toJSON = this_value;
        Number.prototype.toJSON = this_value;
        String.prototype.toJSON = this_value;
    }
    var gap;
    var indent;
    var meta;
    var rep;

    function quote(string) {
        // If the string contains no control characters, no quote characters, and no
        // backslash characters, then we can safely slap some quotes around it.
        // Otherwise we must also replace the offending characters with safe escape
        // sequences.
        rx_escapable.lastIndex = 0;
        return rx_escapable.test(string) ?
            "\"" + string.replace(rx_escapable, function (a) {
                var c = meta[a];
                return typeof c === "string" ?
                    c :
                    "\\u" + ("0000" + a.charCodeAt(0).toString(16)).slice(-4);
            }) + "\"" :
            "\"" + string + "\"";
    }

    function str(key, holder) {
        // Produce a string from holder[key].
        var i; // The loop counter.
        var k; // The member key.
        var v; // The member value.
        var length;
        var mind = gap;
        var partial;
        var value = holder[key];
        // If the value has a toJSON method, call it to obtain a replacement value.
        if (
            value &&
            typeof value === "object" &&
            typeof value.toJSON === "function"
        ) {
            value = value.toJSON(key);
        }
        // If we were called with a replacer function, then call the replacer to
        // obtain a replacement value.
        if (typeof rep === "function") {
            value = rep.call(holder, key, value);
        }
        // What happens next depends on the value's type.
        switch (typeof value) {
            case "string":
                return quote(value);
            case "number":
                // JSON numbers must be finite. Encode non-finite numbers as null.
                return (isFinite(value)) ?
                    String(value) :
                    "null";
            case "boolean":
            case "null":
                // If the value is a boolean or null, convert it to a string. Note:
                // typeof null does not produce "null". The case is included here in
                // the remote chance that this gets fixed someday.
                return String(value);
                // If the type is "object", we might be dealing with an object or an array or
                // null.
            case "object":
                // Due to a specification blunder in ECMAScript, typeof null is "object",
                // so watch out for that case.
                if (!value) {
                    return "null";
                }
                // Make an array to hold the partial results of stringifying this object value.
                gap += indent;
                partial = [];
                // Is the value an array?
                if (Object.prototype.toString.apply(value) === "[object Array]") {
                    // The value is an array. Stringify every element. Use null as a placeholder
                    // for non-JSON values.
                    length = value.length;
                    for (i = 0; i < length; i += 1) {
                        partial[i] = str(i, value) || "null";
                    }
                    // Join all of the elements together, separated with commas, and wrap them in
                    // brackets.
                    v = partial.length === 0 ?
                        "[]" :
                        gap ?
                        (
                            "[\n" +
                            gap +
                            partial.join(",\n" + gap) +
                            "\n" +
                            mind +
                            "]"
                        ) :
                        "[" + partial.join(",") + "]";
                    gap = mind;
                    return v;
                }
                // If the replacer is an array, use it to select the members to be stringified.
                if (rep && typeof rep === "object") {
                    length = rep.length;
                    for (i = 0; i < length; i += 1) {
                        if (typeof rep[i] === "string") {
                            k = rep[i];
                            v = str(k, value);
                            if (v) {
                                partial.push(quote(k) + (
                                    (gap) ?
                                    ": " :
                                    ":"
                                ) + v);
                            }
                        }
                    }
                } else {
                    // Otherwise, iterate through all of the keys in the object.
                    for (k in value) {
                        if (Object.prototype.hasOwnProperty.call(value, k)) {
                            v = str(k, value);
                            if (v) {
                                partial.push(quote(k) + (
                                    (gap) ?
                                    ": " :
                                    ":"
                                ) + v);
                            }
                        }
                    }
                }
                // Join all of the member texts together, separated with commas,
                // and wrap them in braces.
                v = partial.length === 0 ?
                    "{}" :
                    gap ?
                    "{\n" + gap + partial.join(",\n" + gap) + "\n" + mind + "}" :
                    "{" + partial.join(",") + "}";
                gap = mind;
                return v;
        }
    }
    // If the JSON object does not yet have a stringify method, give it one.
    if (typeof JSON.stringify !== "function") {
        meta = { // table of character substitutions
            "\b": "\\b",
            "\t": "\\t",
            "\n": "\\n",
            "\f": "\\f",
            "\r": "\\r",
            "\"": "\\\"",
            "\\": "\\\\"
        };
        JSON.stringify = function (value, replacer, space) {
            // The stringify method takes a value and an optional replacer, and an optional
            // space parameter, and returns a JSON text. The replacer can be a function
            // that can replace values, or an array of strings that will select the keys.
            // A default replacer method can be provided. Use of the space parameter can
            // produce text that is more easily readable.
            var i;
            gap = "";
            indent = "";
            // If the space parameter is a number, make an indent string containing that
            // many spaces.
            if (typeof space === "number") {
                for (i = 0; i < space; i += 1) {
                    indent += " ";
                }
                // If the space parameter is a string, it will be used as the indent string.
            } else if (typeof space === "string") {
                indent = space;
            }
            // If there is a replacer, it must be a function or an array.
            // Otherwise, throw an error.
            rep = replacer;
            if (replacer && typeof replacer !== "function" && (
                    typeof replacer !== "object" ||
                    typeof replacer.length !== "number"
                )) {
                throw new Error("JSON.stringify");
            }
            // Make a fake root object containing our value under the key of "".
            // Return the result of stringifying the value.
            return str("", {
                "": value
            });
        };
    }
    // If the JSON object does not yet have a parse method, give it one.
    if (typeof JSON.parse !== "function") {
        JSON.parse = function (text, reviver) {
            // The parse method takes a text and an optional reviver function, and returns
            // a JavaScript value if the text is a valid JSON text.
            var j;

            function walk(holder, key) {
                // The walk method is used to recursively walk the resulting structure so
                // that modifications can be made.
                var k;
                var v;
                var value = holder[key];
                if (value && typeof value === "object") {
                    for (k in value) {
                        if (Object.prototype.hasOwnProperty.call(value, k)) {
                            v = walk(value, k);
                            if (v !== undefined) {
                                value[k] = v;
                            } else {
                                delete value[k];
                            }
                        }
                    }
                }
                return reviver.call(holder, key, value);
            }
            // Parsing happens in four stages. In the first stage, we replace certain
            // Unicode characters with escape sequences. JavaScript handles many characters
            // incorrectly, either silently deleting them, or treating them as line endings.
            text = String(text);
            rx_dangerous.lastIndex = 0;
            if (rx_dangerous.test(text)) {
                text = text.replace(rx_dangerous, function (a) {
                    return (
                        "\\u" +
                        ("0000" + a.charCodeAt(0).toString(16)).slice(-4)
                    );
                });
            }
            // In the second stage, we run the text against regular expressions that look
            // for non-JSON patterns. We are especially concerned with "()" and "new"
            // because they can cause invocation, and "=" because it can cause mutation.
            // But just to be safe, we want to reject all unexpected forms.
            // We split the second stage into 4 regexp operations in order to work around
            // crippling inefficiencies in IE's and Safari's regexp engines. First we
            // replace the JSON backslash pairs with "@" (a non-JSON character). Second, we
            // replace all simple value tokens with "]" characters. Third, we delete all
            // open brackets that follow a colon or comma or that begin the text. Finally,
            // we look to see that the remaining characters are only whitespace or "]" or
            // "," or ":" or "{" or "}". If that is so, then the text is safe for eval.
            if (
                rx_one.test(
                    text
                    .replace(rx_two, "@")
                    .replace(rx_three, "]")
                    .replace(rx_four, "")
                )
            ) {
                // In the third stage we use the eval function to compile the text into a
                // JavaScript structure. The "{" operator is subject to a syntactic ambiguity
                // in JavaScript: it can begin a block or an object literal. We wrap the text
                // in parens to eliminate the ambiguity.
                j = eval("(" + text + ")");
                // In the optional fourth stage, we recursively walk the new structure, passing
                // each name/value pair to a reviver function for possible transformation.
                return (typeof reviver === "function") ?
                    walk({
                        "": j
                    }, "") :
                    j;
            }
            // If the text is not JSON parseable, then a SyntaxError is thrown.
            throw new SyntaxError("JSON.parse");
        };
    }
}());