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(text, values, callback) {

EventEmitter.call(this);

this.text = null;

this.values = null;

this.callback = null;

this.name = null;

//allow 'config object' as first parameter

if(typeof text == 'object') {

this.text = text.text;

this.values = text.values;

this.name = text.name;

if(typeof values === 'function') {

this.callback = values;

} else if(values) {

this.values = values;

this.callback = callback;

}

} else {

this.text = text;

this.values = values;

this.callback = callback;

if(typeof values == 'function') {

this.values = null;

this.callback = values;

}

}

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(this.callback) {

this.result.command = meta.command.split(' ')[0];

this.result.rowCount = parseInt(meta.value);

this.callback(null, this.result);

}

this.emit('end');

};

module.exports = NativeQuery;