// db.js

var DB;

(function() {

if (DB === undefined) {
    DB = function( mongo , name ){
        this._mongo = mongo;
        this._name = name;
    }
}

DB.prototype.getMongo = function(){
    assert( this._mongo , "why no mongo!" );
    return this._mongo;
}

DB.prototype.getSiblingDB = function( name ){
    return this.getMongo().getDB( name );
}

DB.prototype.getSisterDB = DB.prototype.getSiblingDB;

DB.prototype.getName = function(){
    return this._name;
}

DB.prototype.stats = function(scale){
    return this.runCommand( { dbstats : 1 , scale : scale } );
}

DB.prototype.getCollection = function( name ){
    return new DBCollection( this._mongo , this , name , this._name + "." + name );
}

DB.prototype.commandHelp = function( name ){
    var c = {};
    c[name] = 1;
    c.help = true;
    var res = this.runCommand( c );
    if ( ! res.ok )
        throw Error(res.errmsg);
    return res.help;
}

 // utility to attach readPreference if needed.
 DB.prototype._attachReadPreferenceToCommand = function (cmdObj, readPref) {
     "use strict";
     // if the user has not set a readpref, return the original cmdObj
     if ((readPref === null) || typeof(readPref) !== "object") {
         return cmdObj;
     }

     // if user specifies $readPreference manually, then don't change it
     if (cmdObj.hasOwnProperty("$readPreference")) {
         return cmdObj;
     }

     // copy object so we don't mutate the original
     var clonedCmdObj = Object.extend({}, cmdObj);
     // The server selection spec mandates that the key is '$query', but
     // the shell has historically used 'query'. The server accepts both,
     // so we maintain the existing behavior
     var cmdObjWithReadPref = { query: clonedCmdObj, $readPreference: readPref };
     return cmdObjWithReadPref;
 };

 // if someone passes i.e. runCommand("foo", {bar: "baz"}
 // we merge it in to runCommand({foo: 1, bar: "baz"}
 // this helper abstracts that logic.
 DB.prototype._mergeCommandOptions = function(commandName, extraKeys) {
     "use strict";
     var mergedCmdObj = {};
     mergedCmdObj[commandName] = 1;

     if (typeof(extraKeys) === "object") {
         // this will traverse the prototype chain of extra, but keeping
         // to maintain legacy behavior
         for (var key in extraKeys) {
             mergedCmdObj[key] = extraKeys[key];
         }
     }
     return mergedCmdObj;
 };

 // Like runCommand but applies readPreference if one has been set
 // on the connection. Also sets slaveOk if a (non-primary) readPref has been set.
 DB.prototype.runReadCommand = function (obj, extra) {
     "use strict";

     // Support users who call this function with a string commandName, e.g.
     // db.runReadCommand("commandName", {arg1: "value", arg2: "value"}).
     var mergedObj = (typeof(obj) === "string") ? this._mergeCommandOptions(obj, extra) : obj;
     var cmdObjWithReadPref =
         this._attachReadPreferenceToCommand(mergedObj,
                                             this.getMongo().getReadPref());

     var options = 0;
     // We automatically set slaveOk if readPreference is anything but primary.
     if (this.getMongo().getReadPrefMode() !== "primary") {
         options |= 4;
     }

     // The 'extra' parameter is not used as we have already created a merged command object.
     return this.runCommand(cmdObjWithReadPref, null, options);
 };

 DB.prototype.runCommand = function( obj, extra, queryOptions ){
     var mergedObj = (typeof(obj) === "string") ? this._mergeCommandOptions(obj, extra) : obj;
     // if options were passed (i.e. because they were overridden on a collection), use them.
     // Otherwise use getQueryOptions.
     var options = (typeof(queryOptions) !== "undefined") ? queryOptions : this.getQueryOptions();
     var res;
     try {
         res = this.getMongo().runCommand(this._name, mergedObj, options);
     }
     catch (ex) {
         // When runCommand flowed through query, a connection error resulted in the message
         // "error doing query: failed". Even though this message is arguably incorrect
         // for a command failing due to a connection failure, we preserve it for backwards
         // compatibility. See SERVER-18334 for details.
         if (ex.message.indexOf("network error") >= 0) {
             throw new Error("error doing query: failed");
         }
         throw ex;
     }
     return res;
 };


DB.prototype._dbCommand = DB.prototype.runCommand;
DB.prototype._dbReadCommand = DB.prototype.runReadCommand;

DB.prototype.adminCommand = function( obj, extra ){
    if ( this._name == "admin" )
        return this.runCommand( obj, extra );
    return this.getSiblingDB( "admin" ).runCommand( obj, extra );
}

DB.prototype._adminCommand = DB.prototype.adminCommand; // alias old name

/**
  Create a new collection in the database.  Normally, collection creation is automatic.  You would
   use this function if you wish to specify special options on creation.

   If the collection already exists, no action occurs.

    <p>Options:</p>
    <ul>
    <li>
        size: desired initial extent size for the collection.  Must be <= 1000000000.
              for fixed size (capped) collections, this size is the total/max size of the 
              collection.
    </li>
    <li>
        capped: if true, this is a capped collection (where old data rolls out).
    </li>
    <li> max: maximum number of objects if capped (optional).</li>
    <li> usePowerOf2Sizes: if true, set usePowerOf2Sizes allocation for the collection.</li>
    <li>
        storageEngine: BSON document containing storage engine specific options. Format:
                       {
                           storageEngine: {
                               storageEngine1: {
                                   ...
                               },
                               storageEngine2: {
                                   ...
                               },
                               ...
                           }
                       }
    </li>
    </ul>

    <p>Example:</p>
    <code>db.createCollection("movies", { size: 10 * 1024 * 1024, capped:true } );</code>

 * @param {String} name Name of new collection to create 
 * @param {Object} options Object with options for call.  Options are listed above.
 * @return SOMETHING_FIXME
*/
DB.prototype.createCollection = function(name, opt) {
    var options = opt || {};

    // We have special handling for the 'flags' field, and provide sugar for specific flags. If the
    // user specifies any flags we send the field in the command. Otherwise, we leave it blank and
    // use the server's defaults.
    var sendFlags = false;
    var flags = 0;
    if (options.usePowerOf2Sizes != undefined) {
        print("WARNING: The 'usePowerOf2Sizes' flag is ignored in 3.0 and higher as all MMAPv1 "
            + "collections use fixed allocation sizes unless the 'noPadding' flag is specified");

        sendFlags = true;
        if (options.usePowerOf2Sizes) {
            flags |= 1; // Flag_UsePowerOf2Sizes
        }
        delete options.usePowerOf2Sizes;
    }
    if (options.noPadding != undefined) {
        sendFlags = true;
        if (options.noPadding) {
            flags |= 2; // Flag_NoPadding
        }
        delete options.noPadding;
    }

    // New flags must be added above here.
    if (sendFlags) {
        if (options.flags != undefined)
            throw Error("Can't set 'flags' with either 'usePowerOf2Sizes' or 'noPadding'");
        options.flags = flags;
    }

    var cmd = { create: name };
    Object.extend(cmd, options);

    return this._dbCommand(cmd);
}

/**
 * @deprecated use getProfilingStatus
 *  Returns the current profiling level of this database
 *  @return SOMETHING_FIXME or null on error
 */
DB.prototype.getProfilingLevel  = function() {
    var res = this._dbCommand( { profile: -1 } );
    return res ? res.was : null;
}

/**
 *  @return the current profiling status
 *  example { was : 0, slowms : 100 }
 *  @return SOMETHING_FIXME or null on error
 */
DB.prototype.getProfilingStatus  = function() {
    var res = this._dbCommand( { profile: -1 } );
    if ( ! res.ok )
        throw Error( "profile command failed: " + tojson( res ) );
    delete res.ok
    return res;
}


/**
  Erase the entire database.  (!)

 * @return Object returned has member ok set to true if operation succeeds, false otherwise.
 */
DB.prototype.dropDatabase = function() {
    if ( arguments.length )
        throw Error("dropDatabase doesn't take arguments");
    return this._dbCommand( { dropDatabase: 1 } );
}

/**
 * Shuts down the database.  Must be run while using the admin database.
 * @param opts Options for shutdown. Possible options are:
 *   - force: (boolean) if the server should shut down, even if there is no
 *     up-to-date slave
 *   - timeoutSecs: (number) the server will continue checking over timeoutSecs
 *     if any other servers have caught up enough for it to shut down.
 */
DB.prototype.shutdownServer = function(opts) {
    if( "admin" != this._name ){
        return "shutdown command only works with the admin database; try 'use admin'";
    }

    var cmd = {'shutdown' : 1};
    opts = opts || {};
    for (var o in opts) {
        cmd[o] = opts[o];
    }

    try {
        var res = this.runCommand(cmd);
        if (!res.ok) {
            throw Error('shutdownServer failed: ' + tojson(res));
        }
        throw Error('shutdownServer failed: server is still up.');
    }
    catch (e) {
        // we expect the command to not return a response, as the server will shut down immediately.
        if (e.message === "error doing query: failed") {
            print('server should be down...');
            return;
        }
        throw e;
    }
}

/**
  Clone database on another server to here.
  <p>
  Generally, you should dropDatabase() first as otherwise the cloned information will MERGE 
  into whatever data is already present in this database.  (That is however a valid way to use 
  clone if you are trying to do something intentionally, such as union three non-overlapping
  databases into one.)
  <p>
  This is a low level administrative function will is not typically used.

 * @param {String} from Where to clone from (dbhostname[:port]).  May not be this database 
                   (self) as you cannot clone to yourself.
 * @return Object returned has member ok set to true if operation succeeds, false otherwise.
 * See also: db.copyDatabase()
 */
DB.prototype.cloneDatabase = function(from) { 
    assert( isString(from) && from.length );
    return this._dbCommand( { clone: from } );
}


/**
 Clone collection on another server to here.
 <p>
 Generally, you should drop() first as otherwise the cloned information will MERGE 
 into whatever data is already present in this collection.  (That is however a valid way to use 
 clone if you are trying to do something intentionally, such as union three non-overlapping
 collections into one.)
 <p>
 This is a low level administrative function is not typically used.
 
 * @param {String} from mongod instance from which to clnoe (dbhostname:port).  May
 not be this mongod instance, as clone from self is not allowed.
 * @param {String} collection name of collection to clone.
 * @param {Object} query query specifying which elements of collection are to be cloned.
 * @return Object returned has member ok set to true if operation succeeds, false otherwise.
 * See also: db.cloneDatabase()
 */
DB.prototype.cloneCollection = function(from, collection, query) { 
    assert( isString(from) && from.length );
    assert( isString(collection) && collection.length );
    collection = this._name + "." + collection;
    query = query || {};
    return this._dbCommand( { cloneCollection:collection, from:from, query:query } );
}


/**
  Copy database from one server or name to another server or name.

  Generally, you should dropDatabase() first as otherwise the copied information will MERGE 
  into whatever data is already present in this database (and you will get duplicate objects 
  in collections potentially.)

  For security reasons this function only works when executed on the "admin" db.  However, 
  if you have access to said db, you can copy any database from one place to another.

  This method provides a way to "rename" a database by copying it to a new db name and 
  location.  Additionally, it effectively provides a repair facility.

  * @param {String} fromdb database name from which to copy.
  * @param {String} todb database name to copy to.
  * @param {String} fromhost hostname of the database (and optionally, ":port") from which to 
                    copy the data.  default if unspecified is to copy from self.
  * @return Object returned has member ok set to true if operation succeeds, false otherwise.
  * See also: db.clone()
*/
DB.prototype.copyDatabase = function(fromdb, todb, fromhost, username, password, mechanism) {
    assert( isString(fromdb) && fromdb.length );
    assert( isString(todb) && todb.length );
    fromhost = fromhost || "";

    if (!mechanism) {
        mechanism = this._getDefaultAuthenticationMechanism();
    }
    assert(mechanism == "SCRAM-SHA-1" || mechanism == "MONGODB-CR");

    // Check for no auth or copying from localhost
    if (!username || !password || fromhost == "") {
        return this._adminCommand( { copydb:1, fromhost:fromhost, fromdb:fromdb, todb:todb } );
    }

    // Use the copyDatabase native helper for SCRAM-SHA-1
    if (mechanism == "SCRAM-SHA-1") {
        return this.getMongo().copyDatabaseWithSCRAM(fromdb, todb, fromhost, username, password);
    }

    // Fall back to MONGODB-CR
    var n = this._adminCommand({ copydbgetnonce : 1, fromhost:fromhost});
    return this._adminCommand({ copydb:1, fromhost:fromhost, fromdb:fromdb, todb:todb,
                                username:username, nonce:n.nonce,
                                key:this.__pwHash(n.nonce, username, password) });
}

/**
  Repair database.
 
 * @return Object returned has member ok set to true if operation succeeds, false otherwise.
*/
DB.prototype.repairDatabase = function() {
    return this._dbCommand( { repairDatabase: 1 } );
}


DB.prototype.help = function() {
    print("DB methods:");
    print("\tdb.adminCommand(nameOrDocument) - switches to 'admin' db, and runs command [ just calls db.runCommand(...) ]");
    print("\tdb.auth(username, password)");
    print("\tdb.cloneDatabase(fromhost)");
    print("\tdb.commandHelp(name) returns the help for the command");
    print("\tdb.copyDatabase(fromdb, todb, fromhost)");
    print("\tdb.createCollection(name, { size : ..., capped : ..., max : ... } )");
    print("\tdb.createUser(userDocument)");
    print("\tdb.currentOp() displays currently executing operations in the db");
    print("\tdb.dropDatabase()");
    print("\tdb.eval() - deprecated");
    print("\tdb.fsyncLock() flush data to disk and lock server for backups");
    print("\tdb.fsyncUnlock() unlocks server following a db.fsyncLock()");
    print("\tdb.getCollection(cname) same as db['cname'] or db.cname");
    print("\tdb.getCollectionInfos([filter]) - returns a list that contains the names and options"
          + " of the db's collections");
    print("\tdb.getCollectionNames()");
    print("\tdb.getLastError() - just returns the err msg string");
    print("\tdb.getLastErrorObj() - return full status object");
    print("\tdb.getLogComponents()");
    print("\tdb.getMongo() get the server connection object");
    print("\tdb.getMongo().setSlaveOk() allow queries on a replication slave server");
    print("\tdb.getName()");
    print("\tdb.getPrevError()");
    print("\tdb.getProfilingLevel() - deprecated");
    print("\tdb.getProfilingStatus() - returns if profiling is on and slow threshold");
    print("\tdb.getReplicationInfo()");
    print("\tdb.getSiblingDB(name) get the db at the same server as this one");
    print("\tdb.getWriteConcern() - returns the write concern used for any operations on this db, inherited from server object if set");
    print("\tdb.hostInfo() get details about the server's host"); 
    print("\tdb.isMaster() check replica primary status");
    print("\tdb.killOp(opid) kills the current operation in the db");
    print("\tdb.listCommands() lists all the db commands");
    print("\tdb.loadServerScripts() loads all the scripts in db.system.js");
    print("\tdb.logout()");
    print("\tdb.printCollectionStats()");
    print("\tdb.printReplicationInfo()");
    print("\tdb.printShardingStatus()");
    print("\tdb.printSlaveReplicationInfo()");
    print("\tdb.dropUser(username)");
    print("\tdb.repairDatabase()");
    print("\tdb.resetError()");
    print("\tdb.runCommand(cmdObj) run a database command.  if cmdObj is a string, turns it into { cmdObj : 1 }");
    print("\tdb.serverStatus()");
    print("\tdb.setLogLevel(level,<component>)");
    print("\tdb.setProfilingLevel(level,<slowms>) 0=off 1=slow 2=all");
    print("\tdb.setWriteConcern( <write concern doc> ) - sets the write concern for writes to the db");
    print("\tdb.unsetWriteConcern( <write concern doc> ) - unsets the write concern for writes to the db");
    print("\tdb.setVerboseShell(flag) display extra information in shell output");
    print("\tdb.shutdownServer()");
    print("\tdb.stats()");
    print("\tdb.version() current version of the server");

    return __magicNoPrint;
}

DB.prototype.printCollectionStats = function(scale) { 
    if (arguments.length > 1) { 
        print("printCollectionStats() has a single optional argument (scale)");
        return;
    }
    if (typeof scale != 'undefined') {
        if(typeof scale != 'number') {
            print("scale has to be a number >= 1");
            return;
        }
        if (scale < 1) {
            print("scale has to be >= 1");
            return;
        }
    }
    var mydb = this;
    this.getCollectionNames().forEach(
        function(z) {
            print( z );
            printjson( mydb.getCollection(z).stats(scale) );
            print( "---" );
        }
    );
}

/**
 * <p> Set profiling level for your db.  Profiling gathers stats on query performance. </p>
 * 
 * <p>Default is off, and resets to off on a database restart -- so if you want it on,
 *    turn it on periodically. </p>
 *  
 *  <p>Levels :</p>
 *   <ul>
 *    <li>0=off</li>
 *    <li>1=log very slow operations; optional argument slowms specifies slowness threshold</li>
 *    <li>2=log all</li>
 *  @param {String} level Desired level of profiling
 *  @param {String} slowms For slow logging, query duration that counts as slow (default 100ms)
 *  @return SOMETHING_FIXME or null on error
 */
DB.prototype.setProfilingLevel = function(level,slowms) {
    
    if (level < 0 || level > 2) { 
        var errorText = "input level " + level + " is out of range [0..2]";
        var errorObject = new Error(errorText);
        errorObject['dbSetProfilingException'] = errorText;
        throw errorObject;
    }

    var cmd = { profile: level };
    if ( isNumber( slowms ) )
        cmd["slowms"] = slowms;
    return this._dbCommand( cmd );
}

/**
 * @deprecated
 *  <p> Evaluate a js expression at the database server.</p>
 *
 * <p>Useful if you need to touch a lot of data lightly; in such a scenario
 *  the network transfer of the data could be a bottleneck.  A good example
 *  is "select count(*)" -- can be done server side via this mechanism.
 * </p>
 *
 * <p>
 * If the eval fails, an exception is thrown of the form:
 * </p>
 * <code>{ dbEvalException: { retval: functionReturnValue, ok: num [, errno: num] [, errmsg: str] } }</code>
 *
 * <p>Example: </p>
 * <code>print( "mycount: " + db.eval( function(){db.mycoll.find({},{_id:ObjId()}).length();} );</code>
 *
 * @param {Function} jsfunction Javascript function to run on server.  Note this it not a closure, but rather just "code".
 * @return result of your function, or null if error
 *
 */
DB.prototype.eval = function(jsfunction) {
    print("WARNING: db.eval is deprecated");

    var cmd = { $eval : jsfunction };
    if ( arguments.length > 1 ) {
        cmd.args = argumentsToArray( arguments ).slice(1);
    }
    
    var res = this._dbCommand( cmd );
    
    if (!res.ok)
        throw Error( tojson( res ) );
    
    return res.retval;
}

DB.prototype.dbEval = DB.prototype.eval;


/**
 * 
 *  <p>
 *   Similar to SQL group by.  For example: </p>
 *
 *  <code>select a,b,sum(c) csum from coll where active=1 group by a,b</code>
 *
 *  <p>
 *    corresponds to the following in 10gen:
 *  </p>
 * 
 *  <code>
    db.group(
        {
            ns: "coll",
            key: { a:true, b:true },
            // keyf: ...,
            cond: { active:1 },
            reduce: function(obj,prev) { prev.csum += obj.c; },
            initial: { csum: 0 }
        });
    </code>
 *
 * 
 * <p>
 *  An array of grouped items is returned.  The array must fit in RAM, thus this function is not
 * suitable when the return set is extremely large.
 * </p>
 * <p>
 * To order the grouped data, simply sort it client side upon return.
 * <p>
   Defaults
     cond may be null if you want to run against all rows in the collection
     keyf is a function which takes an object and returns the desired key.  set either key or keyf (not both).
 * </p>
 */
DB.prototype.groupeval = function(parmsObj) {

    var groupFunction = function() {
        var parms = args[0];
        var c = db[parms.ns].find(parms.cond||{});
        var map = new Map();
        var pks = parms.key ? Object.keySet( parms.key ) : null;
        var pkl = pks ? pks.length : 0;
        var key = {};

        while( c.hasNext() ) {
            var obj = c.next();
            if ( pks ) {
                for ( var i=0; i<pkl; i++ ) {
                    var k = pks[i];
                    key[k] = obj[k];
                }
            }
            else {
                key = parms.$keyf(obj);
            }

            var aggObj = map.get(key);
            if( aggObj == null ) {
                var newObj = Object.extend({}, key); // clone
                aggObj = Object.extend(newObj, parms.initial);
                map.put( key, aggObj );
            }
            parms.$reduce(obj, aggObj);
        }

        return map.values();
    }

    return this.eval(groupFunction, this._groupFixParms( parmsObj ));
}

DB.prototype.groupcmd = function( parmsObj ){
    var ret = this.runCommand( { "group" : this._groupFixParms( parmsObj ) } );
    if ( ! ret.ok ){
        throw Error( "group command failed: " + tojson( ret ) );
    }
    return ret.retval;
}

DB.prototype.group = DB.prototype.groupcmd;

DB.prototype._groupFixParms = function( parmsObj ){
    var parms = Object.extend({}, parmsObj);

    if( parms.reduce ) {
        parms.$reduce = parms.reduce; // must have $ to pass to db
        delete parms.reduce;
    }

    if( parms.keyf ) {
        parms.$keyf = parms.keyf;
        delete parms.keyf;
    }

    return parms;
}

DB.prototype.resetError = function(){
    return this.runCommand( { reseterror : 1 } );
}

DB.prototype.forceError = function(){
    return this.runCommand( { forceerror : 1 } );
}

DB.prototype.getLastError = function( w , wtimeout ){
    var res = this.getLastErrorObj( w , wtimeout );
    if ( ! res.ok )
        throw Error( "getlasterror failed: " + tojson( res ) );
    return res.err;
}
DB.prototype.getLastErrorObj = function( w , wtimeout ){
    var cmd = { getlasterror : 1 };
    if ( w ){
        cmd.w = w;
        if ( wtimeout )
            cmd.wtimeout = wtimeout;
    }
    var res = this.runCommand( cmd );

    if ( ! res.ok )
        throw Error( "getlasterror failed: " + tojson( res ) );
    return res;
}
DB.prototype.getLastErrorCmd = DB.prototype.getLastErrorObj;


/* Return the last error which has occurred, even if not the very last error.

   Returns: 
    { err : <error message>, nPrev : <how_many_ops_back_occurred>, ok : 1 }

   result.err will be null if no error has occurred.
 */
DB.prototype.getPrevError = function(){
    return this.runCommand( { getpreverror : 1 } );
}

DB.prototype._getCollectionInfosSystemNamespaces = function(filter) {
    var all = [];

    var dbNamePrefix = this._name + ".";

    // Create a shallow copy of 'filter' in case we modify its 'name' property. Also defaults
    // 'filter' to {} if the parameter was not specified.
    filter = Object.extend({}, filter);
    if (typeof filter.name === "string") {
        // Queries on the 'name' field need to qualify the namespace with the database name for
        // consistency with the command variant.
        filter.name = dbNamePrefix + filter.name;
    }

    var c = this.getCollection( "system.namespaces" ).find(filter);
    while ( c.hasNext() ){
        var infoObj = c.next();
        
        if ( infoObj.name.indexOf( "$" ) >= 0 && infoObj.name.indexOf( ".oplog.$" ) < 0 )
            continue;
        
        // Remove the database name prefix from the collection info object.
        infoObj.name = infoObj.name.substring(dbNamePrefix.length);

        all.push( infoObj );
    }
    
    // Return list of objects sorted by collection name.
    return all.sort(function(coll1, coll2) { return coll1.name.localeCompare(coll2.name); });
}


DB.prototype._getCollectionInfosCommand = function(filter) {
    filter = filter || {};
    var res = this.runCommand({listCollections: 1, filter: filter});
    if ( res.code == 59 ) {
        // command doesn't exist, old mongod
        return null;
    }

    if ( !res.ok ) {
        if ( res.errmsg && res.errmsg.startsWith( "no such cmd" ) ) {
            return null;
        }

        throw Error( "listCollections failed: " + tojson( res ) );
    }

    // The listCollections command returns its results sorted by collection name.  There's no need
    // to re-sort.
    return new DBCommandCursor(this._mongo, res).toArray();
}

/**
 * Returns a list that contains the names and options of this database's collections, sorted by
 * collection name. An optional filter can be specified to match only collections with certain
 * metadata.
 */
DB.prototype.getCollectionInfos = function(filter) {
    var res = this._getCollectionInfosCommand(filter);
    if ( res ) {
        return res;
    }
    return this._getCollectionInfosSystemNamespaces(filter);
}

/**
 * Returns this database's list of collection names in sorted order.
 */
DB.prototype.getCollectionNames = function() {
    return this.getCollectionInfos().map(function(infoObj) { return infoObj.name; });
}

DB.prototype.tojson = function(){
    return this._name;
}

DB.prototype.toString = function(){
    return this._name;
}

DB.prototype.isMaster = function () { return this.runCommand("isMaster"); }

var commandUnsupported = function(res) {
    return (!res.ok &&
            (res.errmsg.startsWith("no such cmd") ||
             res.errmsg.startsWith("no such command") ||
             res.code === 59 /* CommandNotFound */))
};

DB.prototype.currentOp = function(arg) {
    var q = {}
    if ( arg ) {
        if ( typeof( arg ) == "object" )
            Object.extend( q , arg );
        else if ( arg )
            q["$all"] = true;
    }

    var commandObj = {"currentOp": 1};
    Object.extend(commandObj, q);
    var res = this.adminCommand(commandObj);
    if (commandUnsupported(res)) {
        // always send legacy currentOp with default (null) read preference (SERVER-17951)
        var _readPref = this.getMongo().getReadPrefMode();
        try {
            this.getMongo().setReadPref(null);
            res = this.getSiblingDB("admin").$cmd.sys.inprog.findOne( q );
        } finally {
            this.getMongo().setReadPref(_readPref);
        }
    }
    return res;
}
DB.prototype.currentOP = DB.prototype.currentOp;

DB.prototype.killOp = function(op) {
    if( !op ) 
        throw Error("no opNum to kill specified");
    var res = this.adminCommand({'killOp': 1, 'op': op});
    if (commandUnsupported(res)) {
        // fall back for old servers
        var _readPref = this.getMongo().getReadPrefMode();
        try {
            this.getMongo().setReadPref(null);
            res = this.getSiblingDB("admin").$cmd.sys.killop.findOne({'op': op});
        } finally {
            this.getMongo().setReadPref(_readPref);
        }
    }
    return res;
}
DB.prototype.killOP = DB.prototype.killOp;

DB.tsToSeconds = function(x){
    if ( x.t && x.i )
        return x.t;
    return x / 4294967296; // low 32 bits are ordinal #s within a second
}

/** 
  Get a replication log information summary.
  <p>
  This command is for the database/cloud administer and not applicable to most databases.
  It is only used with the local database.  One might invoke from the JS shell:
  <pre>
       use local
       db.getReplicationInfo();
  </pre>
  It is assumed that this database is a replication master -- the information returned is 
  about the operation log stored at local.oplog.$main on the replication master.  (It also 
  works on a machine in a replica pair: for replica pairs, both machines are "masters" from 
  an internal database perspective.
  <p>
  * @return Object timeSpan: time span of the oplog from start to end  if slave is more out 
  *                          of date than that, it can't recover without a complete resync
*/
DB.prototype.getReplicationInfo = function() { 
    var localdb = this.getSiblingDB("local");

    var result = { };
    var oplog;
    var localCollections = localdb.getCollectionNames();
    if (localCollections.indexOf('oplog.rs') >= 0) {
        oplog = 'oplog.rs';
    }
    else if (localCollections.indexOf('oplog.$main') >= 0) {
        oplog = 'oplog.$main';
    }
    else {
        result.errmsg = "neither master/slave nor replica set replication detected";
        return result;
    }

    var ol = localdb.getCollection(oplog);
    var ol_stats = ol.stats();
    if( ol_stats && ol_stats.maxSize ) {
        result.logSizeMB = ol_stats.maxSize / ( 1024 * 1024 );
    } else {
        result.errmsg  = "Could not get stats for local."+oplog+" collection. " +
            "collstats returned: " + tojson(ol_stats);
        return result;
    }

    result.usedMB = ol_stats.size / ( 1024 * 1024 );
    result.usedMB = Math.ceil( result.usedMB * 100 ) / 100;

    var firstc = ol.find().sort({$natural:1}).limit(1);
    var lastc = ol.find().sort({$natural:-1}).limit(1);
    if( !firstc.hasNext() || !lastc.hasNext() ) { 
        result.errmsg = "objects not found in local.oplog.$main -- is this a new and empty db instance?";
        result.oplogMainRowCount = ol.count();
        return result;
    }

    var first = firstc.next();
    var last = lastc.next();
    var tfirst = first.ts;
    var tlast = last.ts;

    if( tfirst && tlast ) { 
        tfirst = DB.tsToSeconds( tfirst ); 
        tlast = DB.tsToSeconds( tlast );
        result.timeDiff = tlast - tfirst;
        result.timeDiffHours = Math.round(result.timeDiff / 36)/100;
        result.tFirst = (new Date(tfirst*1000)).toString();
        result.tLast  = (new Date(tlast*1000)).toString();
        result.now = Date();
    }
    else { 
        result.errmsg = "ts element not found in oplog objects";
    }

    return result;
};

DB.prototype.printReplicationInfo = function() {
    var result = this.getReplicationInfo();
    if( result.errmsg ) {
        if (!this.isMaster().ismaster) {
            print("this is a slave, printing slave replication info.");
            this.printSlaveReplicationInfo();
            return;
        }
        print(tojson(result));
        return;
    }
    print("configured oplog size:   " + result.logSizeMB + "MB");
    print("log length start to end: " + result.timeDiff + "secs (" + result.timeDiffHours + "hrs)");
    print("oplog first event time:  " + result.tFirst);
    print("oplog last event time:   " + result.tLast);
    print("now:                     " + result.now);
}

DB.prototype.printSlaveReplicationInfo = function() {
    var startOptimeDate = null;
    var primary = null;

    function getReplLag(st) {
        assert( startOptimeDate , "how could this be null (getReplLag startOptimeDate)" );
        print("\tsyncedTo: " + st.toString() );
        var ago = (startOptimeDate-st)/1000;
        var hrs = Math.round(ago/36)/100;
        var suffix = "";
        if (primary) {
            suffix = "primary ";
        }
        else {
            suffix = "freshest member (no primary available at the moment)";
        }
        print("\t" + Math.round(ago) + " secs (" + hrs + " hrs) behind the " + suffix);
    };

    function getMaster(members) {
        for (i in members) {
            var row = members[i];
            if (row.state === 1) {
                return row;
            }
        }

        return null;
    };

    function g(x) {
        assert( x , "how could this be null (printSlaveReplicationInfo gx)" )
        print("source: " + x.host);
        if ( x.syncedTo ){
            var st = new Date( DB.tsToSeconds( x.syncedTo ) * 1000 );
            getReplLag(st);
        }
        else {
            print( "\tdoing initial sync" );
        }
    };

    function r(x) {
        assert( x , "how could this be null (printSlaveReplicationInfo rx)" );
        if ( x.state == 1 || x.state == 7 ) {  // ignore primaries (1) and arbiters (7)
            return;
        }
        
        print("source: " + x.name);
        if ( x.optime ) {
            getReplLag(x.optimeDate);
        }
        else {
            print( "\tno replication info, yet.  State: " + x.stateStr );
        }
    };
    
    var L = this.getSiblingDB("local");

    if (L.system.replset.count() != 0) {
        var status = this.adminCommand({'replSetGetStatus' : 1});
        primary = getMaster(status.members);
        if (primary) {
            startOptimeDate = primary.optimeDate; 
        }
        // no primary, find the most recent op among all members
        else {
            startOptimeDate = new Date(0, 0);
            for (i in status.members) {
                if (status.members[i].optimeDate > startOptimeDate) {
                    startOptimeDate = status.members[i].optimeDate;
                }
            }
        }

        for (i in status.members) {
            r(status.members[i]);
        }
    }
    else if( L.sources.count() != 0 ) {
        startOptimeDate = new Date();
        L.sources.find().forEach(g);
    }
    else {
        print("local.sources is empty; is this db a --slave?");
        return;
    }
}

DB.prototype.serverBuildInfo = function(){
    return this._adminCommand( "buildinfo" );
}

// Used to trim entries from the metrics.commands that have never been executed
getActiveCommands = function(tree) {
    var result = { };
    for (var i in tree) {
        if (!tree.hasOwnProperty(i))
            continue;
        if (tree[i].hasOwnProperty("total")) {
            if (tree[i].total > 0) {
                result[i] = tree[i];
            }
            continue;
        }
        if (i == "<UNKNOWN>") {
            if(tree[i] > 0) {
                result[i] = tree[i];
            }
            continue;
        }
        // Handles nested commands
        var subStatus = getActiveCommands(tree[i]);
        if (Object.keys(subStatus).length > 0) {
            result[i] = tree[i];
        }
    }
    return result;
}

DB.prototype.serverStatus = function( options ){
    var cmd = { serverStatus : 1 };
    if ( options ) {
        Object.extend( cmd, options );
    }
    var res = this._adminCommand( cmd );
    // Only prune if we have a metrics tree with commands.
    if (res.metrics && res.metrics.commands) {
            res.metrics.commands = getActiveCommands(res.metrics.commands);
    }
    return res;
}

DB.prototype.hostInfo = function(){
    return this._adminCommand( "hostInfo" );
}

DB.prototype.serverCmdLineOpts = function(){
    return this._adminCommand( "getCmdLineOpts" );
}

DB.prototype.version = function(){
    return this.serverBuildInfo().version;
}

DB.prototype.serverBits = function(){
    return this.serverBuildInfo().bits;
}

DB.prototype.listCommands = function(){
    var x = this.runCommand( "listCommands" );
    for ( var name in x.commands ){
        var c = x.commands[name];

        var s = name + ": ";

        if (c.adminOnly) s += " adminOnly ";
        if (c.slaveOk) s += " slaveOk ";

        s += "\n  ";
        s += c.help.replace(/\n/g, '\n  ');
        s += "\n";
        
        print( s );
    }
}

DB.prototype.printShardingStatus = function( verbose ){
    printShardingStatus( this.getSiblingDB( "config" ) , verbose );
}

DB.prototype.fsyncLock = function() {
    return this.adminCommand({fsync:1, lock:true});
}

DB.prototype.fsyncUnlock = function() {
    var res = this.adminCommand({fsyncUnlock: 1});
    if (commandUnsupported(res)) {
        var _readPref = this.getMongo().getReadPrefMode();
        try {
            this.getMongo().setReadPref(null);
            res = this.getSiblingDB("admin").$cmd.sys.unlock.findOne();
        } finally {
            this.getMongo().setReadPref(_readPref);
        }
    }
    return res;
}

DB.autocomplete = function(obj){
    var colls = obj.getCollectionNames();
    var ret=[];
    for (var i=0; i<colls.length; i++){
        if (colls[i].match(/^[a-zA-Z0-9_.\$]+$/))
            ret.push(colls[i]);
    }
    return ret;
}

DB.prototype.setSlaveOk = function( value ) {
    if( value == undefined ) value = true;
    this._slaveOk = value;
}

DB.prototype.getSlaveOk = function() {
    if (this._slaveOk != undefined) return this._slaveOk;
    return this._mongo.getSlaveOk();
}

DB.prototype.getQueryOptions = function() {
   var options = 0;
   if (this.getSlaveOk()) options |= 4;
   return options;
}

/* Loads any scripts contained in system.js into the client shell.
*/
DB.prototype.loadServerScripts = function(){
    this.system.js.find().forEach(function(u){eval(u._id + " = " + u.value);});
}


////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////// Security shell helpers below //////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////

var _defaultWriteConcern = { w: 'majority', wtimeout: 30 * 1000 }

function getUserObjString(userObj) {
    var pwd = userObj.pwd;
    delete userObj.pwd;
    var toreturn = tojson(userObj);
    userObj.pwd = pwd;
    return toreturn;
}

DB.prototype._modifyCommandToDigestPasswordIfNecessary = function(cmdObj, username) {
    if (!cmdObj["pwd"]) {
        return;
    }
    if (cmdObj.hasOwnProperty("digestPassword")) {
        throw Error("Cannot specify 'digestPassword' through the user management shell helpers, " +
                    "use 'passwordDigestor' instead");
    }
    var passwordDigestor = cmdObj["passwordDigestor"] ? cmdObj["passwordDigestor"] : "client";
    if (passwordDigestor == "server") {
        cmdObj["digestPassword"] = true;
    } else if (passwordDigestor == "client") {
        cmdObj["pwd"] = _hashPassword(username, cmdObj["pwd"]);
        cmdObj["digestPassword"] = false;
    } else {
        throw Error("'passwordDigestor' must be either 'server' or 'client', got: '" +
                    passwordDigestor + "'");
    }
    delete cmdObj["passwordDigestor"];
}

DB.prototype.createUser = function(userObj, writeConcern) {
    var name = userObj["user"];
    var cmdObj = {createUser:name};
    cmdObj = Object.extend(cmdObj, userObj);
    delete cmdObj["user"];

    this._modifyCommandToDigestPasswordIfNecessary(cmdObj, name);

    cmdObj["writeConcern"] = writeConcern ? writeConcern : _defaultWriteConcern;

    var res = this.runCommand(cmdObj);

    if (res.ok) {
        print("Successfully added user: " + getUserObjString(userObj));
        return;
    }

    if (res.errmsg == "no such cmd: createUser") {
        throw Error("'createUser' command not found.  This is most likely because you are " +
                    "talking to an old (pre v2.6) MongoDB server");
    }

    if (res.errmsg == "timeout") {
        throw Error("timed out while waiting for user authentication to replicate - " +
                    "database will not be fully secured until replication finishes");
    }

    throw Error("couldn't add user: " + res.errmsg);
}

function _hashPassword(username, password) {
    if (typeof password != 'string') {
        throw Error("User passwords must be of type string. Was given password with type: " +
                    typeof(password));
    }
    return hex_md5(username + ":mongo:" + password);
}

/**
 * Used for updating users in systems with V1 style user information
 * (ie MongoDB v2.4 and prior)
 */
DB.prototype._updateUserV1 = function(name, updateObject, writeConcern) {
    var setObj = {};
    if (updateObject.pwd) {
        setObj["pwd"] = _hashPassword(name, updateObject.pwd);
    }
    if (updateObject.extraData) {
        setObj["extraData"] = updateObject.extraData;
    }
    if (updateObject.roles) {
        setObj["roles"] = updateObject.roles;
    }

    this.system.users.update({user : name, userSource : null},
                             {$set : setObj});
    var err = this.getLastError(writeConcern['w'], writeConcern['wtimeout']);
    if (err) {
        throw Error("Updating user failed: " + err);
    }
};

DB.prototype.updateUser = function(name, updateObject, writeConcern) {
    var cmdObj = {updateUser:name};
    cmdObj = Object.extend(cmdObj, updateObject);
    cmdObj['writeConcern'] =  writeConcern ? writeConcern : _defaultWriteConcern;
    this._modifyCommandToDigestPasswordIfNecessary(cmdObj, name);

    var res = this.runCommand(cmdObj);
    if (res.ok) {
        return;
    }

    if (res.errmsg == "no such cmd: updateUser") {
        this._updateUserV1(name, updateObject, cmdObj['writeConcern']);
        return;
    }

    throw Error("Updating user failed: " + res.errmsg);
};

DB.prototype.changeUserPassword = function(username, password, writeConcern) {
    this.updateUser(username, {pwd:password}, writeConcern);
};

DB.prototype.logout = function(){
    return this.getMongo().logout(this.getName());
};

// For backwards compatibility
DB.prototype.removeUser = function( username, writeConcern ) {
    print("WARNING: db.removeUser has been deprecated, please use db.dropUser instead");
    return this.dropUser(username, writeConcern);
}

DB.prototype.dropUser = function( username, writeConcern ){
    var cmdObj = {dropUser: username,
                  writeConcern: writeConcern ? writeConcern : _defaultWriteConcern};
    var res = this.runCommand(cmdObj);

    if (res.ok) {
        return true;
    }

    if (res.code == 11) { // Code 11 = UserNotFound
        return false;
    }

    if (res.errmsg == "no such cmd: dropUsers") {
        return this._removeUserV1(username, cmdObj['writeConcern']);
    }

    throw Error(res.errmsg);
}

/**
 * Used for removing users in systems with V1 style user information
 * (ie MongoDB v2.4 and prior)
 */
DB.prototype._removeUserV1 = function(username, writeConcern) {
    this.getCollection( "system.users" ).remove( { user : username } );

    var le = this.getLastErrorObj(writeConcern['w'], writeConcern['wtimeout']);

    if (le.err) {
        throw Error( "Couldn't remove user: " + le.err );
    }

    if (le.n == 1) {
        return true;
    } else {
        return false;
    }
}

DB.prototype.dropAllUsers = function(writeConcern) {
    var res = this.runCommand({dropAllUsersFromDatabase:1,
                               writeConcern: writeConcern ? writeConcern : _defaultWriteConcern});

    if (!res.ok) {
        throw Error(res.errmsg);
    }

    return res.n;
}

DB.prototype.__pwHash = function( nonce, username, pass ) {
    return hex_md5(nonce + username + _hashPassword(username, pass));
}

DB.prototype._defaultAuthenticationMechanism = null;

DB.prototype._getDefaultAuthenticationMechanism = function() {
    // Use the default auth mechanism if set on the command line.
    if (this._defaultAuthenticationMechanism != null)
        return this._defaultAuthenticationMechanism;

    // Use MONGODB-CR for v2.6 and earlier.
    maxWireVersion = this.isMaster().maxWireVersion;
    if (maxWireVersion == undefined || maxWireVersion < 3) {
        return "MONGODB-CR";
    }
    return "SCRAM-SHA-1";
}

DB.prototype._defaultGssapiServiceName = null;

DB.prototype._authOrThrow = function () {
    var params;
    if (arguments.length == 2) {
        params = { user: arguments[0], pwd: arguments[1] };
    }
    else if (arguments.length == 1) {
        if (typeof(arguments[0]) != "object")
            throw Error("Single-argument form of auth expects a parameter object");
        params = Object.extend({}, arguments[0]);
    }
    else {
        throw Error(
            "auth expects either (username, password) or ({ user: username, pwd: password })");
    }

    if (params.mechanism === undefined)
        params.mechanism = this._getDefaultAuthenticationMechanism();

    if (params.db !== undefined) {
        throw Error("Do not override db field on db.auth(). Use getMongo().auth(), instead.");
    }

    if (params.mechanism == "GSSAPI" &&
        params.serviceName == null &&
        this._defaultGssapiServiceName != null) {

        params.serviceName = this._defaultGssapiServiceName;
    }

    params.db = this.getName();
    var good = this.getMongo().auth(params);
    if (good) {
        // auth enabled, and should try to use isMaster and replSetGetStatus to build prompt
        this.getMongo().authStatus = {authRequired:true, isMaster:true, replSetGetStatus:true};
    }

    return good;
}


DB.prototype.auth = function() {
    var ex;
    try {
        this._authOrThrow.apply(this, arguments);
    } catch (ex) {
        print(ex);
        return 0;
    }
    return 1;
}

DB.prototype.grantRolesToUser = function(username, roles, writeConcern) {
    var cmdObj = {grantRolesToUser: username,
                  roles: roles,
                  writeConcern: writeConcern ? writeConcern : _defaultWriteConcern};
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }
}

DB.prototype.revokeRolesFromUser = function(username, roles, writeConcern) {
    var cmdObj = {revokeRolesFromUser: username,
                  roles: roles,
                  writeConcern: writeConcern ? writeConcern : _defaultWriteConcern};
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }
}

DB.prototype.getUser = function(username, args) {
    if (typeof username != "string") {
        throw Error("User name for getUser shell helper must be a string");
    }
    var cmdObj = {usersInfo: username};
    Object.extend(cmdObj, args);

    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }

    if (res.users.length == 0) {
        return null;
    }
    return res.users[0];
}

DB.prototype.getUsers = function(args) {
    var cmdObj = {usersInfo: 1};
    Object.extend(cmdObj, args);
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        var authSchemaIncompatibleCode = 69;
        if (res.code == authSchemaIncompatibleCode ||
                (res.code == null && res.errmsg == "no such cmd: usersInfo")) {
            // Working with 2.4 schema user data
            return this.system.users.find({}).toArray();
        }

        throw Error(res.errmsg);
    }

    return res.users;
}

DB.prototype.createRole = function(roleObj, writeConcern) {
    var name = roleObj["role"];
    var cmdObj = {createRole:name};
    cmdObj = Object.extend(cmdObj, roleObj);
    delete cmdObj["role"];
    cmdObj["writeConcern"] = writeConcern ? writeConcern : _defaultWriteConcern;

    var res = this.runCommand(cmdObj);

    if (!res.ok) {
        throw Error(res.errmsg);
    }
    printjson(roleObj);
}

DB.prototype.updateRole = function(name, updateObject, writeConcern) {
    var cmdObj = {updateRole:name};
    cmdObj = Object.extend(cmdObj, updateObject);
    cmdObj['writeConcern'] =  writeConcern ? writeConcern : _defaultWriteConcern;
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }
};

DB.prototype.dropRole = function(name, writeConcern) {
    var cmdObj = {dropRole:name,
                  writeConcern: writeConcern ? writeConcern : _defaultWriteConcern};
    var res = this.runCommand(cmdObj);

    if (res.ok) {
        return true;
    }

    if (res.code == 31) { // Code 31 = RoleNotFound
        return false;
    }

    throw Error(res.errmsg);
};

DB.prototype.dropAllRoles = function(writeConcern) {
    var res = this.runCommand({dropAllRolesFromDatabase:1,
                               writeConcern: writeConcern ? writeConcern : _defaultWriteConcern});

    if (!res.ok) {
        throw Error(res.errmsg);
    }

    return res.n;
}

DB.prototype.grantRolesToRole = function(rolename, roles, writeConcern) {
    var cmdObj = {grantRolesToRole: rolename,
                  roles: roles,
                  writeConcern: writeConcern ? writeConcern : _defaultWriteConcern};
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }
}

DB.prototype.revokeRolesFromRole = function(rolename, roles, writeConcern) {
    var cmdObj = {revokeRolesFromRole: rolename,
                  roles: roles,
                  writeConcern: writeConcern ? writeConcern : _defaultWriteConcern};
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }
}

DB.prototype.grantPrivilegesToRole = function(rolename, privileges, writeConcern) {
    var cmdObj = {grantPrivilegesToRole: rolename,
                  privileges: privileges,
                  writeConcern: writeConcern ? writeConcern : _defaultWriteConcern};
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }
}

DB.prototype.revokePrivilegesFromRole = function(rolename, privileges, writeConcern) {
    var cmdObj = {revokePrivilegesFromRole: rolename,
                  privileges: privileges,
                  writeConcern: writeConcern ? writeConcern : _defaultWriteConcern};
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }
}

DB.prototype.getRole = function(rolename, args) {
    if (typeof rolename != "string") {
        throw Error("Role name for getRole shell helper must be a string");
    }
    var cmdObj = {rolesInfo:rolename};
    Object.extend(cmdObj, args);
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }

    if (res.roles.length == 0) {
        return null;
    }
    return res.roles[0];
}

DB.prototype.getRoles = function(args) {
    var cmdObj = {rolesInfo:1};
    Object.extend(cmdObj, args);
    var res = this.runCommand(cmdObj);
    if (!res.ok) {
        throw Error(res.errmsg);
    }

    return res.roles;
}

DB.prototype.setWriteConcern = function( wc ) {
    if ( wc instanceof WriteConcern ) {
        this._writeConcern = wc;
    }
    else {
        this._writeConcern = new WriteConcern( wc );
    }
};

DB.prototype.getWriteConcern = function() {
    if (this._writeConcern)
        return this._writeConcern;
    
    if (this._mongo.getWriteConcern())
        return this._mongo.getWriteConcern();

    return null;
};

DB.prototype.unsetWriteConcern = function() {
    delete this._writeConcern;
};

DB.prototype.getLogComponents = function() {
    return this.getMongo().getLogComponents();
}

DB.prototype.setLogLevel = function(logLevel, component) {
    return this.getMongo().setLogLevel(logLevel, component);
}

}());