<?php

class DatabaseQuery
{
  const COMBINE_TYPE_AND = ' AND ';
  const COMBINE_TYPE_OR = ' OR ';
  const JOIN_TYPE_INNER = ' INNER ';
  const JOIN_TYPE_LEFT = ' LEFT ';
  
  private $mapper;

  private $table;
  private $columns = array();
  private $where = array();
  private $order = array();
  private $limit;
  private $offset;
  private $join = array();
  
  private $db;
  
  public function __construct(DataMapper $mapper)
  {
    $this->mapper = $mapper;
    $this->from($mapper->getTableName(), $mapper->getColumnNames());
  }

  public function from($table, $columns = null)
  {
    $this->table = (string)$table;
    $this->columns = (array)$columns;
    return $this;
  }

  public function where($condition, $values = null, $conditionName = null)
  {
    $condition = (string)$condition;
    if ($values !== null)
      $condition = $this->db->quoteInto($condition, $values);
    if ($conditionName !== null && !is_numeric($conditionName))
      $this->where[$conditionName] = $condition;
    else
      $this->where[] = $condition;
    return $this;
  }

  public function combineWhere($conditionName1, $conditionName2, $combineType = self::COMBINE_TYPE_AND, $conditionName = null)
  {
    $condition1 = isset($this->where[$conditionName1]) ? $this->where[$conditionName1] : null;
    $condition2 = isset($this->where[$conditionName2]) ? $this->where[$conditionName2] : null;

    if ($condition1 !== null && $condition2 !== null) {
      unset($this->where[$conditionName1], $this->where[$conditionName2]);
      $this->where($condition1 . ' ' . $combineType . ' ' . $condition2, null, $conditionName);
    }
    return $this;
  }

  public function resetWhere()
  {
    $this->where = array();
    return $this;
  }

  public function order($column)
  {
    $this->order[] = (string)$column;
    return $this;
  }

  public function resetOrder()
  {
    $this->order = array();
    return $this;
  }

  public function limit($limit, $offset = null)
  {
    $this->limit = ($limit === null) ? null : (int)$limit;
    $this->offset = ($offset === null) ? null : (int)$offset;
    return $this;
  }
  
  public function with($relationName)
  {
    $this->join(self::JOIN_TYPE_INNER, $tableName, $on, $columns);
    return $this;
  }
}