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

var Query = function() {
  EventEmitter.call(this);
};

sys.inherits(Query, EventEmitter);

var intParser = {
  fromDbValue: parseInt
};

var floatParser = {
  fromDbValue: parseFloat
};

var timeParser = {
  fromDbValue: function(isoTime) {
    var when = new Date();
    var split = isoTime.split(':');
    when.setHours(split[0]);
    when.setMinutes(split[1]);
    when.setSeconds(split[2].split('-') [0]);
    return when;
  }
};

Query.dataTypes = {
  20: intParser,
  21: intParser,
  23: intParser,
  26: intParser,
  1700: floatParser,
  700: floatParser,
  701: floatParser,
  1083: timeParser,
  1266: timeParser
};

var p = Query.prototype;

p.processRowDescription = function(description) {
  this.fields = description.fields;
};

p.processDataRow = function(dataRow) {
  var row = dataRow.fields;
  var fields = this.fields || [];
  var field, dataType;
  for(var i = 0, len = row.length; i < len; i++) {
    field = fields[i] || 0
    var dataType = Query.dataTypes[field.dataTypeID];
    if(dataType) {
      row[i] = dataType.fromDbValue(row[i]);
    }
  }
  this.emit('row',row);
};

p.toBuffer = function() {
  var textBuffer = new Buffer(this.text+'\0','utf8');
  var len = textBuffer.length + 4;
  var fullBuffer = new Buffer(len + 1);
  fullBuffer[0] = 0x51;
  fullBuffer[1] = len >>> 24;
  fullBuffer[2] = len >>> 16;
  fullBuffer[3] = len >>> 8;
  fullBuffer[4] = len >>> 0;
  textBuffer.copy(fullBuffer,5,0);
  return fullBuffer;
};

module.exports = Query;