/**
* Module dependencies.
* @ignore
*/
var BinaryParser = require('./binary_parser').BinaryParser;
/**
* Machine id.
*
* Create a random 3-byte value (i.e. unique for this
* process). Other drivers use a md5 of the machine id here, but
* that would mean an asyc call to gethostname, so we don't bother.
* @ignore
*/
var MACHINE_ID = parseInt(Math.random() * 0xFFFFFF, 10);
// Regular expression that checks for hex value
var checkForHexRegExp = new RegExp("^[0-9a-fA-F]{24}$");
/**
* Create a new ObjectID instance
*
* @class Represents a BSON ObjectId type.
* @param {(string|number)} id Can be a 24 byte hex string, 12 byte binary string or a Number.
* @property {number} generationTime The generation time of this ObjectId instance
* @return {ObjectID} instance of ObjectID.
*/
var ObjectID = function ObjectID(id) {
if(!(this instanceof ObjectID)) return new ObjectID(id);
if((id instanceof ObjectID)) return id;
this._bsontype = 'ObjectID';
var __id = null;
var valid = ObjectID.isValid(id);
// Throw an error if it's not a valid setup
if(!valid && id != null){
throw new Error("Argument passed in must be a single String of 12 bytes or a string of 24 hex characters");
} else if(valid && typeof id == 'string' && id.length == 24) {
return ObjectID.createFromHexString(id);
} else if(id == null || typeof id == 'number') {
// convert to 12 byte binary string
this.id = this.generate(id);
} else if(id != null && id.length === 12) {
// assume 12 byte string
this.id = id;
}
if(ObjectID.cacheHexString) this.__id = this.toHexString();
};
// Allow usage of ObjectId as well as ObjectID
var ObjectId = ObjectID;
// Precomputed hex table enables speedy hex string conversion
var hexTable = [];
for (var i = 0; i < 256; i++) {
hexTable[i] = (i <= 15 ? '0' : '') + i.toString(16);
}
/**
* Return the ObjectID id as a 24 byte hex string representation
*
* @method
* @return {string} return the 24 byte hex string representation.
*/
ObjectID.prototype.toHexString = function() {
if(ObjectID.cacheHexString && this.__id) return this.__id;
var hexString = '';
for (var i = 0; i < this.id.length; i++) {
hexString += hexTable[this.id.charCodeAt(i)];
}
if(ObjectID.cacheHexString) this.__id = hexString;
return hexString;
};
/**
* Update the ObjectID index used in generating new ObjectID's on the driver
*
* @method
* @return {number} returns next index value.
* @ignore
*/
ObjectID.prototype.get_inc = function() {
return ObjectID.index = (ObjectID.index + 1) % 0xFFFFFF;
};
/**
* Update the ObjectID index used in generating new ObjectID's on the driver
*
* @method
* @return {number} returns next index value.
* @ignore
*/
ObjectID.prototype.getInc = function() {
return this.get_inc();
};
/**
* Generate a 12 byte id string used in ObjectID's
*
* @method
* @param {number} [time] optional parameter allowing to pass in a second based timestamp.
* @return {string} return the 12 byte id binary string.
*/
ObjectID.prototype.generate = function(time) {
if ('number' != typeof time) {
time = parseInt(Date.now()/1000,10);
}
var time4Bytes = BinaryParser.encodeInt(time, 32, true, true);
/* for time-based ObjectID the bytes following the time will be zeroed */
var machine3Bytes = BinaryParser.encodeInt(MACHINE_ID, 24, false);
var pid2Bytes = BinaryParser.fromShort(typeof process === 'undefined' ? Math.floor(Math.random() * 100000) : process.pid);
var index3Bytes = BinaryParser.encodeInt(this.get_inc(), 24, false, true);
return time4Bytes + machine3Bytes + pid2Bytes + index3Bytes;
};
/**
* Converts the id into a 24 byte hex string for printing
*
* @return {String} return the 24 byte hex string representation.
* @ignore
*/
ObjectID.prototype.toString = function() {
return this.toHexString();
};
/**
* Converts to a string representation of this Id.
*
* @return {String} return the 24 byte hex string representation.
* @ignore
*/
ObjectID.prototype.inspect = ObjectID.prototype.toString;
/**
* Converts to its JSON representation.
*
* @return {String} return the 24 byte hex string representation.
* @ignore
*/
ObjectID.prototype.toJSON = function() {
return this.toHexString();
};
/**
* Compares the equality of this ObjectID with `otherID`.
*
* @method
* @param {object} otherID ObjectID instance to compare against.
* @return {boolean} the result of comparing two ObjectID's
*/
ObjectID.prototype.equals = function equals (otherID) {
if(otherID == null) return false;
var id = (otherID instanceof ObjectID || otherID.toHexString)
? otherID.id
: ObjectID.createFromHexString(otherID).id;
return this.id === id;
}
/**
* Returns the generation date (accurate up to the second) that this ID was generated.
*
* @method
* @return {date} the generation date
*/
ObjectID.prototype.getTimestamp = function() {
var timestamp = new Date();
timestamp.setTime(Math.floor(BinaryParser.decodeInt(this.id.substring(0,4), 32, true, true)) * 1000);
return timestamp;
}
/**
* @ignore
*/
ObjectID.index = parseInt(Math.random() * 0xFFFFFF, 10);
/**
* @ignore
*/
ObjectID.createPk = function createPk () {
return new ObjectID();
};
/**
* Creates an ObjectID from a second based number, with the rest of the ObjectID zeroed out. Used for comparisons or sorting the ObjectID.
*
* @method
* @param {number} time an integer number representing a number of seconds.
* @return {ObjectID} return the created ObjectID
*/
ObjectID.createFromTime = function createFromTime (time) {
var id = BinaryParser.encodeInt(time, 32, true, true) +
BinaryParser.encodeInt(0, 64, true, true);
return new ObjectID(id);
};
/**
* Creates an ObjectID from a hex string representation of an ObjectID.
*
* @method
* @param {string} hexString create a ObjectID from a passed in 24 byte hexstring.
* @return {ObjectID} return the created ObjectID
*/
ObjectID.createFromHexString = function createFromHexString (hexString) {
// Throw an error if it's not a valid setup
if(typeof hexString === 'undefined' || hexString != null && hexString.length != 24)
throw new Error("Argument passed in must be a single String of 12 bytes or a string of 24 hex characters");
var len = hexString.length;
if(len > 12*2) {
throw new Error('Id cannot be longer than 12 bytes');
}
var result = ''
, string
, number;
for (var index = 0; index < len; index += 2) {
string = hexString.substr(index, 2);
number = parseInt(string, 16);
result += BinaryParser.fromByte(number);
}
return new ObjectID(result, hexString);
};
/**
* Checks if a value is a valid bson ObjectId
*
* @method
* @return {boolean} return true if the value is a valid bson ObjectId, return false otherwise.
*/
ObjectID.isValid = function isValid(id) {
if(id == null) return false;
if(id != null && 'number' != typeof id && (id.length != 12 && id.length != 24)) {
return false;
} else {
// Check specifically for hex correctness
if(typeof id == 'string' && id.length == 24) return checkForHexRegExp.test(id);
return true;
}
};
/**
* @ignore
*/
Object.defineProperty(ObjectID.prototype, "generationTime", {
enumerable: true
, get: function () {
return Math.floor(BinaryParser.decodeInt(this.id.substring(0,4), 32, true, true));
}
, set: function (value) {
var value = BinaryParser.encodeInt(value, 32, true, true);
this.id = value + this.id.substr(4);
// delete this.__id;
this.toHexString();
}
});
/**
* Expose.
*/
module.exports = ObjectID;
module.exports.ObjectID = ObjectID;
module.exports.ObjectId = ObjectID;