var EventEmitter = require('events').EventEmitter;

var util = require('util');

var types = require(__dirname + '/../types');

var utils = require(__dirname + '/../utils');

var Result = require(__dirname + '/../result');

//event emitter proxy

var NativeQuery = function(config, values, callback) {

// use of "new" optional

if (!(this instanceof NativeQuery)) return new NativeQuery(config, values, callback);

EventEmitter.call(this);

config = utils.normalizeQueryConfig(config, values, callback);

this.name = config.name;

this.text = config.text;

this.values = config.values;

this.callback = config.callback;

this._result = new Result();

//normalize values

if(this.values) {

for(var i = 0, len = this.values.length; i < len; i++) {

this.values[i] = utils.prepareValue(this.values[i]);

}

}

};

util.inherits(NativeQuery, EventEmitter);

var p = NativeQuery.prototype;

//maps from native rowdata into api compatible row object

var mapRowData = function(row) {

var result = {};

for(var i = 0, len = row.length; i < len; i++) {

var item = row[i];

result[item.name] = item.value == null ? null : types.getTypeParser(item.type, 'text')(item.value);

}

return result;

}

p.handleRow = function(rowData) {

var row = mapRowData(rowData);

if(this.callback) {

this._result.addRow(row);

}

this.emit('row', row, this._result);

};

p.handleError = function(error) {

if(this.callback) {

this.callback(error);

this.callback = null;

} else {

this.emit('error', error);

}

}

p.handleReadyForQuery = function(meta) {

if(meta) {

this._result.addCommandComplete(meta);

}

if(this.callback) {

this.callback(null, this._result);

}

this.emit('end', this._result);

};

module.exports = NativeQuery;