/*
 *  Falcon MongoDB - Extension
 */

#include "mongodb_ext.h"
#include "mongodb_mod.h"
#include "mongodb_srv.h"
#include "mongodb_st.h"

#include <falcon/engine.h>
#include <falcon/vm.h>

#include <stdio.h>//debug..

extern Falcon::MongoDBService theMongoDBService;

/*#
    @beginmodule mongodb
 */

namespace Falcon
{
namespace Ext
{

/*#
    @class MongoDBError
    @brief Error generated MongoDB operations.
    @optparam code The error code
    @optparam desc The description for the error code
    @optparam extra Extra information specifying the error conditions.
    @from Error( code, desc, extra )
*/
FALCON_FUNC MongoDBError_init( VMachine* vm )
{
    CoreObject *einst = vm->self().asObject();

    if ( einst->getUserData() == 0 )
        einst->setUserData( new MongoDBError );

    ::Falcon::core::Error_init( vm );
}

/*******************************************************************************
    MongoDB class
*******************************************************************************/

/*#
    @class MongoDB
    @brief Create a client connection to a MongoDB database.
    @optparam host default to localhost.
    @optparam port default to 27017.
 */
FALCON_FUNC MongoDBConnection_init( VMachine* vm )
{
    Item* i_host = vm->param( 0 );
    Item* i_port = vm->param( 1 );

    if ( ( i_host && !i_host->isString() )
        || ( i_port && !i_port->isInteger() ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "[S,I]" ) );
    }

    const char* host;
    AutoCString zHost;
    if ( i_host )
    {
        zHost.set( *i_host );
        host = zHost.c_str();
    }
    else
        host = "127.0.0.1";

    int port = i_port ? i_port->asInteger() : 27017;

    MongoDB::Connection* conn = 0;
    conn = new MongoDB::Connection( host, port, 0 );
    if ( !conn )
    {
        throw new MongoDBError( ErrorParam( MONGODB_ERR_CREATE_CONN, __LINE__ )
                                .desc( FAL_STR( _err_create_conn ) ) );
    }
    CoreObject* self = vm->self().asObjectSafe();
    self->setUserData( conn );
    vm->retval( self );
}

/*#
    @method host MongoDB
    @optparam host
    @brief When given a parameter, change the host for the next connection attempt. Else return the current host.
    @return self (with param) or the current host.
 */
FALCON_FUNC MongoDBConnection_host( VMachine* vm )
{
    Item* i_host = vm->param( 0 );

    if ( i_host && !i_host->isString() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                              .extra( "[S]" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );

    if ( i_host ) // set host
    {
        AutoCString zHost( *i_host );
        conn->hostPort( zHost.c_str() );
        vm->retval( self );
    }
    else // get host
    {
        String s( conn->host() );
        s.bufferize();
        vm->retval( s );
    }
}

/*#
    @method port MongoDB
    @optparam port
    @brief When given a parameter, change the port for the next connection attempt. Else return the current port.
    @return self (with param) or the current port.
 */
FALCON_FUNC MongoDBConnection_port( VMachine* vm )
{
    Item* i_port = vm->param( 0 );

    if ( i_port && !i_port->isInteger() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                              .extra( "[I]" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );

    if ( i_port ) // set port
    {
        conn->hostPort( 0, i_port->asInteger() );
        vm->retval( self );
    }
    else // get port
    {
        vm->retval( conn->port() );
    }
}

/*#
    @method connect MongoDB
    @brief Connect or reconnect to MongoDB server.
 */
FALCON_FUNC MongoDBConnection_connect( VMachine* vm )
{
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );

    int ret = conn->connect();
    if ( ret != mongo_conn_success )
    {
        switch ( ret )
        {
        case -1:
            throw new MongoDBError( ErrorParam( MONGODB_ERR_NOMEM, __LINE__ )
                                    .desc( FAL_STR( _err_nomem ) ) );
        case mongo_conn_bad_arg:
            throw new MongoDBError( ErrorParam( MONGODB_ERR_CONNECT, __LINE__ )
                                    .desc( FAL_STR( _err_connect_bad_arg ) ) );
        case mongo_conn_no_socket:
            throw new MongoDBError( ErrorParam( MONGODB_ERR_CONNECT, __LINE__ )
                                    .desc( FAL_STR( _err_connect_no_socket ) ) );
        case mongo_conn_not_master:
            throw new MongoDBError( ErrorParam( MONGODB_ERR_CONNECT, __LINE__ )
                                    .desc( FAL_STR( _err_connect_not_master ) ) );
        case mongo_conn_fail:
        default:
            throw new MongoDBError( ErrorParam( MONGODB_ERR_CONNECT, __LINE__ )
                                    .desc( FAL_STR( _err_connect_fail ) ) );
        }
    }
}


/*#
    @method disconnect MongoDB
    @brief Disconnect to MongoDB server.
 */
FALCON_FUNC MongoDBConnection_disconnect( VMachine* vm )
{
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );

    int ret = conn->disconnect();
    // we just ignore errors.
    //if ( ret ) printf( "Disconnection error (%d)\n", ret );
}


/*#
    @method isConnected MongoDB
	@brief Checks if the DB is connected.
    @return true if connected
 */
FALCON_FUNC MongoDBConnection_isConnected( VMachine* vm )
{
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );
    vm->retval( conn->isConnected() );
}


/*#
    @method authenticate MongoDB
	@brief Authenticates a user on the DB.
	@param db Database
    @param user User ID
    @param pass Password
    @return true if authenticated
	
 */
FALCON_FUNC MongoDBConnection_authenticate( VMachine* vm )
{
    Item* i_db = vm->param( 0 );
    Item* i_user = vm->param( 1 );
    Item* i_pass = vm->param( 2 );

    if ( !i_db || !i_db->isString()
        || !i_user || !i_user->isString()
        || !i_pass || !i_pass->isString() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,S,S" ) );
    }

    AutoCString zDB( *i_db );
    AutoCString zUser( *i_user );
    AutoCString zPass( *i_pass );

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );
    bool b = conn->authenticate( zDB.c_str(), zUser.c_str(), zPass.c_str() );
    vm->retval( b );
}


/*#
    @method addUser MongoDB
	@brief Adds a user to the DB.
    @param db Database
    @param user User ID to be added
    @param pass Password for the new user.
    @return true if user was added
 */
FALCON_FUNC MongoDBConnection_addUser( VMachine* vm )
{
    Item* i_db = vm->param( 0 );
    Item* i_user = vm->param( 1 );
    Item* i_pass = vm->param( 2 );

    if ( !i_db || !i_db->isString()
        || !i_user || !i_user->isString()
        || !i_pass || !i_pass->isString() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,S,S" ) );
    }

    AutoCString zDB( *i_db );
    AutoCString zUser( *i_user );
    AutoCString zPass( *i_pass );

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );
    bool b = conn->addUser( zDB.c_str(), zUser.c_str(), zPass.c_str() );
    vm->retval( b );
}


/*#
    @method dropDatabase MongoDB
	@brief Drops the database.
    @param db The database to be dropped
    @return true on success
 */
FALCON_FUNC MongoDBConnection_dropDatabase( VMachine* vm )
{
    Item* i_db = vm->param( 0 );

    if ( !i_db || !i_db->isString() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S" ) );
    }

    AutoCString zDB( *i_db );
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );
    bool b = conn->dropDatabase( zDB.c_str() );
    vm->retval( b );
}


/*#
    @method dropCollection MongoDB
	@brief Removes a collection from a database.
    @param db The database
    @param coll The collection to be dropped
    @return true on success
 */
FALCON_FUNC MongoDBConnection_dropCollection( VMachine* vm )
{
    Item* i_db = vm->param( 0 );
    Item* i_coll = vm->param( 1 );

    if ( !i_db || !i_db->isString()
        || !i_coll || !i_coll->isString() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,S" ) );
    }

    AutoCString zDB( *i_db );
    AutoCString zColl( *i_coll );
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );
    bool b = conn->dropCollection( zDB.c_str(), zColl.c_str() );
    vm->retval( b );
}


/*#
    @method insert MongoDB
	@brief Inserts an instance.
    @param ns namespace 
    @param bson BSONObj instance, or an array of BSON instances
    @return true on success
 */
FALCON_FUNC MongoDBConnection_insert( VMachine* vm )
{
    Item* i_ns = vm->param( 0 );
    Item* i_bobj = vm->param( 1 );

    if ( !i_ns || !i_ns->isString()
        || !i_bobj
        || !( i_bobj->isArray()
        || ( i_bobj->isObject() && i_bobj->asObjectSafe()->derivedFrom( "BSON" ) ) ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,BSON|A" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );
    bool b;

    if ( i_bobj->isObject() )
    {
        CoreObject* obj = i_bobj->asObjectSafe();
        MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( obj->getUserData() );
        b = conn->insert( *i_ns->asString(), bobj );
    }
    else // is array
    {
        AutoCString zNs( *i_ns );
        b = conn->insert( zNs.c_str(), *i_bobj->asArray() );
    }
    vm->retval( b );
}


/*#
    @method update MongoDB
	@brief Updates an existing instance.
    @param ns namespace
    @param cond BSON instance (conditions)
    @param op BSON instance (operations)
    @optparam upsert (boolean) default true
    @optparam multiple (boolean) default true
    @return true on success
 */
FALCON_FUNC MongoDBConnection_update( VMachine* vm )
{
    Item* i_ns = vm->param( 0 );
    Item* i_cond = vm->param( 1 );
    Item* i_op = vm->param( 2 );
    Item* i_upsert = vm->param( 3 );
    Item* i_multi = vm->param( 4 );

    if ( !i_ns || !i_ns->isString()
        || !i_cond || !( i_cond->isObject() && i_cond->asObjectSafe()->derivedFrom( "BSON" ) )
        || !i_op || !( i_op->isObject() && i_op->asObjectSafe()->derivedFrom( "BSON" ) )
        || ( i_upsert && !i_upsert->isBoolean() )
        || ( i_multi && !i_multi->isBoolean() ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,BSON,BSON,[B,B]" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );

    AutoCString zNs( *i_ns );
    MongoDB::BSONObj* cond = static_cast<MongoDB::BSONObj*>( i_cond->asObjectSafe()->getUserData() );
    MongoDB::BSONObj* op = static_cast<MongoDB::BSONObj*>( i_op->asObjectSafe()->getUserData() );
    const bool upsert = i_upsert ? i_upsert->asBoolean() : true;
    const bool multi = i_multi ? i_multi->asBoolean() : true;

    vm->retval( conn->update( zNs.c_str(), cond, op, upsert, multi ) );
}


/*#
    @method remove MongoDB
	@brief Removes an instance.
    @param ns namespace
    @param cond BSON instance (conditions)
    @return true on success
 */
FALCON_FUNC MongoDBConnection_remove( VMachine* vm )
{
    Item* i_ns = vm->param( 0 );
    Item* i_cond = vm->param( 1 );

    if ( !i_ns || !i_ns->isString()
        || !i_cond || !( i_cond->isObject() && i_cond->asObjectSafe()->derivedFrom( "BSON" ) ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,BSON" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );

    AutoCString zNs( *i_ns );
    MongoDB::BSONObj* cond = static_cast<MongoDB::BSONObj*>( i_cond->asObjectSafe()->getUserData() );

    vm->retval( conn->remove( zNs.c_str(), cond ) );
}


/*#
    @method findOne MongoDB
	@brief Finds an instance.
    @param ns namespace
    @optparam query BSON instance
    @return BSON result or nil
 */
FALCON_FUNC MongoDBConnection_findOne( VMachine* vm )
{
    Item* i_ns = vm->param( 0 );
    Item* i_query = vm->param( 1 );

    if ( !i_ns || !i_ns->isString()
        || ( i_query && !( i_query->isObject() && i_query->asObjectSafe()->derivedFrom( "BSON" ) ) ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,[BSON]" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );

    AutoCString zNs( *i_ns );
    MongoDB::BSONObj* ret = 0;
    bool b;

    if ( i_query )
    {
        MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( i_query->asObjectSafe()->getUserData() );
        b = conn->findOne( zNs.c_str(), bobj, &ret );
    }
    else
        b = conn->findOne( zNs.c_str(), 0, &ret );

    if ( b )
    {
        fassert( ret );
        Item* wki = vm->findWKI( "BSON" );
        CoreObject* obj = wki->asClass()->createInstance();
        fassert( !obj->getUserData() );
        obj->setUserData( ret );
        vm->retval( obj );
    }
    else
        vm->retnil();
}


/*#
    @method find MongoDB
    @brief Finds instances corresponding to the given query.
    @param ns Namespace
    @optparam query BSON instance
    @optparam fields BSON instance
    @optparam skip default 0
    @optparam limit default 0 (all)
    @return An array of BSON results or nil
 */
FALCON_FUNC MongoDBConnection_find( VMachine* vm )
{
    Item* i_ns = vm->param( 0 );
    Item* i_query = vm->param( 1 );
    Item* i_fields = vm->param( 2 );
    Item* i_skip = vm->param( 3 );
    Item* i_limit = vm->param( 4 );

    if ( !i_ns || !i_ns->isString()
        || ( i_query && !( i_query->isObject() && i_query->asObjectSafe()->derivedFrom( "BSON" ) ) )
        || ( i_fields && !( i_fields->isObject() && i_fields->asObjectSafe()->derivedFrom( "BSON" ) ) )
        || ( i_skip && !i_skip->isInteger() )
        || ( i_limit && !i_limit->isInteger() ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,[BSON,BSON,I,I]" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );

    AutoCString zNs( *i_ns );
    MongoDB::BSONObj* query = i_query ?
        static_cast<MongoDB::BSONObj*>( i_query->asObjectSafe()->getUserData() ) : 0;
    MongoDB::BSONObj* fields = i_fields ?
        static_cast<MongoDB::BSONObj*>( i_fields->asObjectSafe()->getUserData() ) : 0;
    const int skip = i_skip ? i_skip->asInteger() : 0;
    const int limit = i_limit ? i_limit->asInteger() : 0;
    CoreArray* res;

    const bool b = conn->find( zNs.c_str(), query, fields, skip, limit, &res );
    if ( b )
        vm->retval( res );
    else
        vm->retnil();
}


/*#
    @method count MongoDB
	@brief Counts the entities in a collection.
    @param db Database
    @param coll Collection to be queried.
    @optparam query BSON instance
    @return Total count or -1 on error
 */
FALCON_FUNC MongoDBConnection_count( VMachine* vm )
{
    Item* i_db = vm->param( 0 );
    Item* i_coll = vm->param( 1 );
    Item* i_query = vm->param( 2 );

    if ( !i_db || !i_db->isString()
        || !i_coll || !i_coll->isString()
        || ( i_query && !( i_query->isObject() && i_query->asObjectSafe()->derivedFrom( "BSON" ) ) ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,S,[BSON]" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );

    AutoCString db( *i_db );
    AutoCString coll( *i_coll );
    int64 n = -1;

    if ( i_query )
    {
        MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( i_query->asObjectSafe()->getUserData() );
        n = conn->count( db.c_str(), coll.c_str(), bobj );
    }
    else
        n = conn->count( db.c_str(), coll.c_str() );

    vm->retval( n );
}


/*#
    @method command MongoDB
    @brief Run a command on a database
    @param db Database
    @param cmd BSON instance
    @return BSON result or nil
 */
FALCON_FUNC MongoDBConnection_command( VMachine* vm )
{
    Item* i_db = vm->param( 0 );
    Item* i_cmd = vm->param( 1 );

    if ( !i_db || !i_db->isString()
        || !i_cmd || !( i_cmd->isObject() && i_cmd->asObjectSafe()->derivedFrom( "BSON" ) ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,BSON" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );
    AutoCString db( *i_db );
    MongoDB::BSONObj* cmd = static_cast<MongoDB::BSONObj*>( i_cmd->asObjectSafe()->getUserData() );
    MongoDB::BSONObj* res;

    if ( conn->command( db.c_str(), cmd, &res ) )
    {
        Item* wki = vm->findWKI( "BSON" );
        CoreObject* obj = wki->asClass()->createInstance();
        obj->setUserData( res );
        vm->retval( obj );
    }
    else
        vm->retnil();
}


/*#
    @method createIndex MongoDB
	@brief Creates an index for the given namespace and key.
    @param ns namespace
    @param key BSON instance
    @optparam unique (boolean) default false
    @optparam drop_dups (boolean) default false
    @return BSON result or nil
 */
FALCON_FUNC MongoDBConnection_createIndex( VMachine* vm )
{
    Item* i_ns = vm->param( 0 );
    Item* i_key = vm->param( 1 );
    Item* i_uniq = vm->param( 2 );
    Item* i_drups = vm->param( 3 );

    if ( !i_ns || !i_ns->isString()
        || !i_key || !( i_key->isObject() && i_key->asObjectSafe()->derivedFrom( "BSON" ) )
        || ( i_uniq && !i_uniq->isBoolean() )
        || ( i_drups && !i_drups->isBoolean() ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S,BSON,[B,B]" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::Connection* conn = static_cast<MongoDB::Connection*>( self->getUserData() );
    AutoCString zNs( *i_ns );
    MongoDB::BSONObj* key = static_cast<MongoDB::BSONObj*>( i_key->asObjectSafe()->getUserData() );
    const bool uniq = i_uniq ? i_uniq->asBoolean() : false;
    const bool drups = i_drups ? i_drups->asBoolean() : false;
    MongoDB::BSONObj* res;

    if ( conn->createIndex( zNs.c_str(), key, uniq, drups, &res ) )
    {
        CoreObject* obj = vm->findWKI( "BSON" )->asClass()->createInstance();
        obj->setUserData( res );
        vm->retval( obj );
    }
    else
        vm->retnil();
}

/*******************************************************************************
    ObjectID class
*******************************************************************************/

/*#
    @class ObjectID
    @brief Mongo Object ID
    @optparam string A string representing an object Id.
 */
FALCON_FUNC MongoOID_init( VMachine* vm )
{
    Item* i_s = vm->param( 0 );

    if ( i_s && !i_s->isString() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "[S]" ) );
    }

    MongoDB::ObjectID* self = static_cast<MongoDB::ObjectID*>( vm->self().asObjectSafe() );

    if ( i_s )
    {
        AutoCString zStr( *i_s );
        self->fromString( zStr.c_str() );
    }

    vm->retval( self );
}


/*#
    @method toString ObjectID
    @brief Returns a representation of the object id as a string.
    @return A string representing the object id.
 */
FALCON_FUNC MongoOID_toString( VMachine* vm )
{
    MongoDB::ObjectID* self = static_cast<MongoDB::ObjectID*>( vm->self().asObjectSafe() );
    String s( self->toString() );
    s.bufferize();
    vm->retval( s );
}


/*******************************************************************************
    BSON class
*******************************************************************************/

/*#
    @class BSON
    @brief Represents a BSON object.
    @optparam param An integer (reserved space for internal buffer) or a dict to append.

    If no dict is given, an "empty" bson object is created.
 */
FALCON_FUNC MongoBSON_init( VMachine* vm )
{
    Item* i_parm = vm->param( 0 );

    if ( i_parm && !( i_parm->isInteger() || i_parm->isDict() ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "[I|D]" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    const int bytes = i_parm && i_parm->isInteger() ? i_parm->asInteger() : 0;
    MongoDB::BSONObj* bobj = 0;
    bobj = new MongoDB::BSONObj( bytes );

    if ( !bobj )
    {
        throw new MongoDBError( ErrorParam( MONGODB_ERR_CREATE_BSON, __LINE__ )
                                .desc( FAL_STR( _err_create_bsonobj ) ) );
    }

    if ( i_parm && i_parm->isDict() ) // append the data
    {
        const int ret = bobj->appendMany( *i_parm->asDict() );
        if ( ret == 1 ) // bad key
        {
            delete bobj;
            throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                        .extra( "S" ) );
        }
        else
        if ( ret == 2 ) // bad value
        {
            delete bobj;
            throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                        .extra( FAL_STR( _err_inv_item ) ) );
        }
    }

    self->setUserData( bobj );
    vm->retval( self );
}

/*#
    @method reset BSON
    @brief Clear the BSON object, making it an "empty" one.
    @optparam bytes Reserve some space for internal buffer.
 */
FALCON_FUNC MongoBSON_reset( VMachine* vm )
{
    Item* i_bytes = vm->param( 0 );

    if ( i_bytes && !i_bytes->isInteger() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "[I]" ) );
    }

    const int bytes = i_bytes ? i_bytes->asInteger() : 0;
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( self->getUserData() );
    bobj->reset( bytes );
}


/*#
    @method genOID BSON
    @brief Generate and append an OID.
    @optparam name Key name (default "_id")
    @return self
 */
FALCON_FUNC MongoBSON_genOID( VMachine* vm )
{
    Item* i_nm = vm->param( 0 );

    if ( i_nm && !i_nm->isString() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "[S]" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( self->getUserData() );

    if ( i_nm )
    {
        AutoCString zNm( *i_nm );
        bobj->genOID( zNm.c_str() );
    }
    else
        bobj->genOID( "_id" );

    vm->retval( self );
}


/*#
    @method append BSON
    @brief Append some data to the BSON object
    @param dict A dict (with keys that must be strings...)
    @return self

    Example:
    @code
        import from mongo
        obj = mongo.BSON().genOID().append( [ "key" => "value" ] )
    @endcode
 */
FALCON_FUNC MongoBSON_append( VMachine* vm )
{
    Item* i_dic = vm->param( 0 );

    if ( !i_dic || !i_dic->isDict() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "D" ) );
    }

    CoreDict* dic = i_dic->asDict();
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( self->getUserData() );
    const int ret = bobj->appendMany( *dic );
    if ( ret == 1 ) // bad key
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                    .extra( "S" ) );
    }
    else
    if ( ret == 2 ) // bad value
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                    .extra( FAL_STR( _err_inv_item ) ) );
    }
    vm->retval( self );
}


/*#
    @method asDict BSON
    @brief Return a dictionary representing the BSON object.
	@return A dictionary
 */
FALCON_FUNC MongoBSON_asDict( VMachine* vm )
{
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( self->getUserData() );
    vm->retval( bobj->asDict() );
}


/*#
    @method hasKey BSON
	@brief Checks if the collection contains the required key.
    @param key
    @return true if BSON has that key
 */
FALCON_FUNC MongoBSON_hasKey( VMachine* vm )
{
    Item* i_key = vm->param( 0 );

    if ( !i_key || !i_key->isString() )
    {
         throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( self->getUserData() );
    AutoCString key( *i_key );
    vm->retval( bobj->hasKey( key.c_str() ) );
}


/*#
    @method value BSON
    @brief Get the value for a given key.
    @param key The researched key.
    @return value for key given (might be nil!), or nil if not found.
 */
FALCON_FUNC MongoBSON_value( VMachine* vm )
{
    Item* i_key = vm->param( 0 );

    if ( !i_key || !i_key->isString() )
    {
         throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( self->getUserData() );
    AutoCString key( *i_key );
    Item* it = bobj->value( key.c_str() );
    if ( it )
        vm->retval( *it );
    else
        vm->retnil();
}

/*******************************************************************************
    BSONIter class
*******************************************************************************/

/*#
    @class BSONIter
    @brief Iterator for BSON objects
    @param bson A BSON object

    Example:
    @code
        iter = BSONIter( bson )
        while iter.next()
            doSomething( iter.key(), iter.value() )
        end
    @endcode

    The iterator copies data from given BSON object, and is completely
    independant and cannot be changed or updated. (This is of course suboptimal
    and could be optimized later.)
 */
FALCON_FUNC MongoBSONIter_init( VMachine* vm )
{
    Item* i_data = vm->param( 0 );

    if ( !i_data
        || !( i_data->isObject() && i_data->asObjectSafe()->derivedFrom( "BSON" ) ) )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "BSON" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    CoreObject* data = i_data->asObjectSafe();
    MongoDB::BSONObj* bobj = static_cast<MongoDB::BSONObj*>( data->getUserData() );
    MongoDB::BSONIter* iter = new MongoDB::BSONIter( bobj );
    self->setUserData( iter );
    vm->retval( self );
}


/*#
    @method next BSONIter
    @brief Return true if there is more data to iterate over
	@return True if the iterator could advance, false if it was the last element.
 */
FALCON_FUNC MongoBSONIter_next( VMachine* vm )
{
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONIter* iter = static_cast<MongoDB::BSONIter*>( self->getUserData() );
    vm->retval( iter->next() );
}


/*#
    @method key BSONIter
    @brief Get the current BSON key string
	@return The current key.
 */
FALCON_FUNC MongoBSONIter_key( VMachine* vm )
{
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONIter* iter = static_cast<MongoDB::BSONIter*>( self->getUserData() );
    const char* k = iter->currentKey();
    if ( k )
    {
        String s( k );
        s.bufferize();
        vm->retval( s );
    }
    else
        vm->retnil();
}


/*#
    @method value BSONIter
    @brief Get the current BSON value
    @return The current value.
 */
FALCON_FUNC MongoBSONIter_value( VMachine* vm )
{
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONIter* iter = static_cast<MongoDB::BSONIter*>( self->getUserData() );
    Item* v = iter->currentValue();
    if ( v )
        vm->retval( *v );
    else
        vm->retnil();
}


/*#
    @method reset BSONIter
    @brief Reset to start of iterator.
 */
FALCON_FUNC MongoBSONIter_reset( VMachine* vm )
{
    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONIter* iter = static_cast<MongoDB::BSONIter*>( self->getUserData() );
    iter->reset();
}


/*#
    @method find BSONIter
    @param name Key name
    @brief Return true when (and set iterator position where) name is found in the BSON.
	@return True if the key can be found, false otherwise.

    If false is returned, iterator is at end (and you may have to reset it).
    This method does a reset before searching.
 */
FALCON_FUNC MongoBSONIter_find( VMachine* vm )
{
    Item* i_nm = vm->param( 0 );

    if ( !i_nm || !i_nm->isString() )
    {
        throw new ParamError( ErrorParam( e_inv_params, __LINE__ )
                .extra( "S" ) );
    }

    CoreObject* self = vm->self().asObjectSafe();
    MongoDB::BSONIter* iter = static_cast<MongoDB::BSONIter*>( self->getUserData() );
    AutoCString zNm( *i_nm->asString() );
    vm->retval( iter->find( zNm.c_str() ) );
}


} /* !namespace Ext */
} /* !namespace Falcon */