Initial implementation and test for database types

lib/Cake/Model/Datasource/Database/Type.php

@@ -0,0 +1,173 @@
+<?php
+
+namespace Cake\Model\Datasource\Database;
+
+use PDO,
+	Exception,
+	Cake\Model\Datasource\Database\Driver;
+
+/**
+ * Encapsultes all conversion functions for values coming from database into PHP and
+ * going from PHP into database.
+ **/
+class Type {
+
+/**
+ * List of supported database types . A humand readable
+ * identifier is used as key and a complete namespaced class name as value
+ * representing the class that will do actual type conversions.
+ *
+ * @var array
+ **/
+	protected static $_types = array(
+		'boolean' => '\Cake\Model\Datasource\Database\Type\BooleanType',
+		'binary' => '\Cake\Model\Datasource\Database\Type\BinaryType',
+		'date' => '\Cake\Model\Datasource\Database\Type\DateType',
+		'datetime' => '\Cake\Model\Datasource\Database\Type\DateTimeType',
+		'time' => '\Cake\Model\Datasource\Database\Type\TimeType'
+	);
+
+/**
+ * List of mbasic type mappings, used to avoid having to instantiate a class
+ * for doing conversion on these
+ *
+ * @var array
+ **/
+	protected static $_basicTypes = array(
+		'float' => array('php' => 'floatval'),
+		'integer' => array('php' => 'intval', 'pdo' => PDO::PARAM_INT),
+		'string' => array('php' => 'strval'),
+		'text' => array('php' => 'strval'),
+	);
+
+/**
+ * Contains a map of type object instances to be reused if needed
+ *
+ * @var array
+ **/
+	protected static $_builtTypes = array();
+
+/**
+ * Identifier name for this type
+ *
+ * @var string
+ **/
+	protected $_name = null;
+
+/**
+ * Constructor
+ *
+ * @param string $name The name identifying this type
+ * @return void
+ **/
+	public function __construct($name = null) {
+		$this->_name = $name;
+	}
+
+/**
+ * Returns a Type object capable of converting a type identifyed by $name
+ *
+ * @param string $name type identifier
+ * @return Type
+ **/
+	public static function build($name) {
+		if (isset(self::$_builtTypes[$name])) {
+			return self::$_builtTypes[$name];
+		}
+		if (isset(self::$_basicTypes[$name])) {
+			return self::$_builtTypes[$name] = new self($name);
+		}
+		if (!isset(self::$_types[$name])) {
+			throw new \InvalidArgumentException('No such type');
+		}
+		return self::$_builtTypes[$name] = new self::$_types[$name]($name);
+	}
+
+/**
+ * Registers a new type identifier and maps it to a fully namespaced classname,
+ * If called with no arguments it will return current types map array
+ * If $className is ommited it will return mapped class for $type
+ *
+ * @param string|array $type if string name of type to map, if array list of arrays to be mapped
+ * @param string $className
+ * @return array|string|null if $type is null then array with current map, if $className is null string
+ * configured class name for give $type, null otherwise
+ **/
+	public static function map($type = null, $className = null) {
+		if ($type === null) {
+			return self::$_types;
+		}
+		if (!is_string($type)) {
+			self::$_types = $type;
+			return;
+		}
+		if ($className === null) {
+			return isset(self::$_types[$type]) ? self::$_types[$type] : null;
+		}
+		self::$_types[$type] = $className;
+	}
+
+/**
+ * Clears out all created intences and mapped types classes, useful for testing
+ *
+ * @return void
+ **/
+	public static function clear() {
+		self::$_types = array();
+		self::$_builtTypes = array();
+	}
+
+/**
+ * Returns type identifier name for this object
+ *
+ * @return string
+ **/
+	public function getName() {
+		return $this->_name;
+	}
+
+/**
+ * Casts given value to one acceptable by database
+ *
+ * @param mixed $value value to be converted to database equivalent
+ * @param Driver $driver object from which database preferences and configuration will be extracted
+ * @return mixed
+ **/
+	public function toDatabase($value, Driver $driver) {
+		return $value;
+	}
+
+/**
+ * Casts given value to PHP equivalent
+ *
+ * @param mixed $value value to be converted to PHP equivalent
+ * @param Driver $driver object from which database preferences and configuration will be extracted
+ * @return mixed
+ **/
+	public function toPHP($value, $driver) {
+		if (!empty(self::$_basicTypes[$this->_name])) {
+			$typeInfo = self::$_basicTypes[$this->_name];
+			$value = ($value === null) ? null : $value;
+			if (isset($typeInfo['php'])) {
+				return $typeInfo['php']($value);
+			}
+		}
+		return $value;
+	}
+
+/**
+ * Casts give value to Statement equivalent
+ *
+ * @param mixed $value value to be converted to PHP equivalent
+ * @param Driver $driver object from which database preferences and configuration will be extracted
+ * @return mixed
+ **/
+	public function toStatement($value, $driver) {
+		if (!empty(self::$_basicTypes[$this->_name])) {
+			$typeInfo = self::$_basicTypes[$this->_name];
+			return isset($typeInfo['pdo']) ? $typeInfo['pdo'] : PDO::PARAM_STR;
+		}
+		return PDO::PARAM_STR;
+	}
+
+}