<?php
/**
 * TDbTableColumn class file.
 *
 * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
 * @link https://github.com/pradosoft/prado
 * @license https://github.com/pradosoft/prado/blob/master/LICENSE
 */

namespace Prado\Data\Common;

use PDO;

/**
 * TDbTableColumn class describes the column meta data of the schema for a database table.
 *
 * @author Wei Zhuo <weizho[at]gmail[dot]com>
 * @since 3.1
 */
class TDbTableColumn extends \Prado\TComponent
{
	public const UNDEFINED_VALUE = INF; //use infinity for undefined value

	private $_info = [];

	/**
	 * Sets the table column meta data.
	 * @param array $columnInfo table column information.
	 */
	public function __construct($columnInfo)
	{
		$this->_info = $columnInfo;
		parent::__construct();
	}

	/**
	 * @param string $name information array key name
	 * @param mixed $default default value if information array value is null
	 * @return mixed information array value.
	 */
	protected function getInfo($name, $default = null)
	{
		return $this->_info[$name] ?? $default;
	}

	/**
	 * @param string $name information array key name
	 * @param mixed $value new information array value.
	 */
	protected function setInfo($name, $value)
	{
		$this->_info[$name] = $value;
	}

	/**
	 * Returns the derived PHP primitive type from the db type. Default returns 'string'.
	 * @return string derived PHP primitive type from the column db type.
	 */
	public function getPHPType()
	{
		return 'string';
	}

	/**
	 * @return int PDO bind param/value types, default returns string.
	 */
	public function getPdoType()
	{
		switch ($this->getPHPType()) {
			case 'boolean': return PDO::PARAM_BOOL;
			case 'integer': return PDO::PARAM_INT;
			case 'string': return PDO::PARAM_STR;
		}
		return PDO::PARAM_STR;
	}

	/**
	 * @return string name of the column in the table (identifier quoted).
	 */
	public function getColumnName()
	{
		return $this->getInfo('ColumnName');
	}

	/**
	 * @return string name of the column with quoted identifier.
	 */
	public function getColumnId()
	{
		return $this->getInfo('ColumnId');
	}

	/**
	 * @return string size of the column.
	 */
	public function getColumnSize()
	{
		return $this->getInfo('ColumnSize');
	}

	/**
	 * @return int zero-based ordinal position of the column in the table.
	 */
	public function getColumnIndex()
	{
		return $this->getInfo('ColumnIndex');
	}

	/**
	 * @return string column type.
	 */
	public function getDbType()
	{
		return $this->getInfo('DbType');
	}

	/**
	 * @return bool specifies whether value Null is allowed, default is false.
	 */
	public function getAllowNull()
	{
		return $this->getInfo('AllowNull', false);
	}

	/**
	 * @return mixed default column value if column value was null.
	 */
	public function getDefaultValue()
	{
		return $this->getInfo('DefaultValue', self::UNDEFINED_VALUE);
	}

	/**
	 * @return string precision of the column data, if the data is numeric.
	 */
	public function getNumericPrecision()
	{
		return $this->getInfo('NumericPrecision');
	}

	/**
	 * @return string scale of the column data, if the data is numeric.
	 */
	public function getNumericScale()
	{
		return $this->getInfo('NumericScale');
	}

	public function getMaxiumNumericConstraint()
	{
		if (($precision = $this->getNumericPrecision()) !== null) {
			$scale = $this->getNumericScale();
			return $scale === null ? pow(10, (int) $precision) : pow(10, (int) $precision - (int) $scale);
		}
	}

	/**
	 * @return bool whether this column is a primary key for the table, default is false.
	 */
	public function getIsPrimaryKey()
	{
		return $this->getInfo('IsPrimaryKey', false);
	}

	/**
	 * @return bool whether this column is a foreign key, default is false.
	 */
	public function getIsForeignKey()
	{
		return $this->getInfo('IsForeignKey', false);
	}

	/**
	 * @return string sequence name, only applicable if column is a sequence
	 */
	public function getSequenceName()
	{
		return $this->getInfo('SequenceName');
	}

	/**
	 * @return bool whether the column is a sequence.
	 */
	public function hasSequence()
	{
		return $this->getSequenceName() !== null;
	}

	/**
	 * @return bool whether this column is excluded from insert and update.
	 */
	public function getIsExcluded()
	{
		return false;
	}
}