<?php defined('SYSPATH') or die('No direct script access.');
/**
 * Array helper.
 *
 * @package    Kohana
 * @category   Helpers
 * @author     Kohana Team
 * @copyright  (c) 2007-2011 Kohana Team
 * @license    http://kohanaframework.org/license
 */
class Kohana_Arr {

	/**
	 * @var  string  default delimiter for path()
	 */
	public static $delimiter = '.';

	/**
	 * Tests if an array is associative or not.
	 *
	 *     // Returns TRUE
	 *     Arr::is_assoc(array('username' => 'john.doe'));
	 *
	 *     // Returns FALSE
	 *     Arr::is_assoc('foo', 'bar');
	 *
	 * @param   array   array to check
	 * @return  boolean
	 */
	public static function is_assoc(array $array)
	{
		// Keys of the array
		$keys = array_keys($array);

		// If the array keys of the keys match the keys, then the array must
		// not be associative (e.g. the keys array looked like {0:0, 1:1...}).
		return array_keys($keys) !== $keys;
	}

	/**
	 * Test if a value is an array with an additional check for array-like objects.
	 *
	 *     // Returns TRUE
	 *     Arr::is_array(array());
	 *     Arr::is_array(new ArrayObject);
	 *
	 *     // Returns FALSE
	 *     Arr::is_array(FALSE);
	 *     Arr::is_array('not an array!');
	 *     Arr::is_array(Database::instance());
	 *
	 * @param   mixed    value to check
	 * @return  boolean
	 */
	public static function is_array($value)
	{
		if (is_array($value))
		{
			// Definitely an array
			return TRUE;
		}
		else
		{
			// Possibly a Traversable object, functionally the same as an array
			return (is_object($value) AND $value instanceof Traversable);
		}
	}

	/**
	 * Gets a value from an array using a dot separated path.
	 *
	 *     // Get the value of $array['foo']['bar']
	 *     $value = Arr::path($array, 'foo.bar');
	 *
	 * Using a wildcard "*" will search intermediate arrays and return an array.
	 *
	 *     // Get the values of "color" in theme
	 *     $colors = Arr::path($array, 'theme.*.color');
	 *
	 *     // Using an array of keys
	 *     $colors = Arr::path($array, array('theme', '*', 'color'));
	 *
	 * @param   array   array to search
	 * @param   mixed   key path string (delimiter separated) or array of keys
	 * @param   mixed   default value if the path is not set
	 * @param   string  key path delimiter
	 * @return  mixed
	 */
	public static function path($array, $path, $default = NULL, $delimiter = NULL)
	{
		if ( ! Arr::is_array($array))
		{
			// This is not an array!
			return $default;
		}

		if (is_array($path))
		{
			// The path has already been separated into keys
			$keys = $path;
		}
		else
		{
			if (array_key_exists($path, $array))
			{
				// No need to do extra processing
				return $array[$path];
			}

			if ($delimiter === NULL)
			{
				// Use the default delimiter
				$delimiter = Arr::$delimiter;
			}

			// Remove starting delimiters and spaces
			$path = ltrim($path, "{$delimiter} ");

			// Remove ending delimiters, spaces, and wildcards
			$path = rtrim($path, "{$delimiter} *");

			// Split the keys by delimiter
			$keys = explode($delimiter, $path);
		}

		do
		{
			$key = array_shift($keys);

			if (ctype_digit($key))
			{
				// Make the key an integer
				$key = (int) $key;
			}

			if (isset($array[$key]))
			{
				if ($keys)
				{
					if (Arr::is_array($array[$key]))
					{
						// Dig down into the next part of the path
						$array = $array[$key];
					}
					else
					{
						// Unable to dig deeper
						break;
					}
				}
				else
				{
					// Found the path requested
					return $array[$key];
				}
			}
			elseif ($key === '*')
			{
				// Handle wildcards

				$values = array();
				foreach ($array as $arr)
				{
					if ($value = Arr::path($arr, implode('.', $keys)))
					{
						$values[] = $value;
					}
				}

				if ($values)
				{
					// Found the values requested
					return $values;
				}
				else
				{
					// Unable to dig deeper
					break;
				}
			}
			else
			{
				// Unable to dig deeper
				break;
			}
		}
		while ($keys);

		// Unable to find the value requested
		return $default;
	}

	/**
	* Set a value on an array by path.
	*
	* @see Arr::path()
	* @param array   $array     Array to update
	* @param string  $path      Path
	* @param mixed   $value     Value to set
	* @param string  $delimiter Path delimiter
	*/
	public static function set_path( & $array, $path, $value, $delimiter = NULL)
	{
		if ( ! $delimiter)
		{
			// Use the default delimiter
			$delimiter = Arr::$delimiter;
		}

		// Split the keys by delimiter
		$keys = explode($delimiter, $path);

		// Set current $array to inner-most array path
		while (count($keys) > 1)
		{
			$key = array_shift($keys);

			if (ctype_digit($key))
			{
				// Make the key an integer
				$key = (int) $key;
			}

			if ( ! isset($array[$key]))
			{
				$array[$key] = array();
			}

			$array = & $array[$key];
		}

		// Set key on inner-most array
		$array[array_shift($keys)] = $value;
	}

	/**
	 * Fill an array with a range of numbers.
	 *
	 *     // Fill an array with values 5, 10, 15, 20
	 *     $values = Arr::range(5, 20);
	 *
	 * @param   integer  stepping
	 * @param   integer  ending number
	 * @return  array
	 */
	public static function range($step = 10, $max = 100)
	{
		if ($step < 1)
			return array();

		$array = array();
		for ($i = $step; $i <= $max; $i += $step)
		{
			$array[$i] = $i;
		}

		return $array;
	}

	/**
	 * Retrieve a single key from an array. If the key does not exist in the
	 * array, the default value will be returned instead.
	 *
	 *     // Get the value "username" from $_POST, if it exists
	 *     $username = Arr::get($_POST, 'username');
	 *
	 *     // Get the value "sorting" from $_GET, if it exists
	 *     $sorting = Arr::get($_GET, 'sorting');
	 *
	 * @param   array   array to extract from
	 * @param   string  key name
	 * @param   mixed   default value
	 * @return  mixed
	 */
	public static function get($array, $key, $default = NULL)
	{
		return isset($array[$key]) ? $array[$key] : $default;
	}

	/**
	 * Retrieves multiple keys from an array. If the key does not exist in the
	 * array, the default value will be added instead.
	 *
	 *     // Get the values "username", "password" from $_POST
	 *     $auth = Arr::extract($_POST, array('username', 'password'));
	 *
	 * @param   array   array to extract keys from
	 * @param   array   list of key names
	 * @param   mixed   default value
	 * @return  array
	 */
	public static function extract($array, array $keys, $default = NULL)
	{
		$found = array();
		foreach ($keys as $key)
		{
			$found[$key] = isset($array[$key]) ? $array[$key] : $default;
		}

		return $found;
	}

	/**
	 * Retrieves muliple single-key values from a list of arrays.
	 *
	 *     // Get all of the "id" values from a result
	 *     $ids = Arr::pluck($result, 'id');
	 *
	 * [!!] A list of arrays is an array that contains arrays, eg: array(array $a, array $b, array $c, ...)
	 *
	 * @param   array   list of arrays to check
	 * @param   string  key to pluck
	 * @return  array
	 */
	public static function pluck($array, $key)
	{
		$values = array();

		foreach ($array as $row)
		{
			if (isset($row[$key]))
			{
				// Found a value in this row
				$values[] = $row[$key];
			}
		}

		return $values;
	}

	/**
	 * Adds a value to the beginning of an associative array.
	 *
	 *     // Add an empty value to the start of a select list
	 *     Arr::unshift($array, 'none', 'Select a value');
	 *
	 * @param   array   array to modify
	 * @param   string  array key name
	 * @param   mixed   array value
	 * @return  array
	 */
	public static function unshift( array & $array, $key, $val)
	{
		$array = array_reverse($array, TRUE);
		$array[$key] = $val;
		$array = array_reverse($array, TRUE);

		return $array;
	}

	/**
	 * Recursive version of [array_map](http://php.net/array_map), applies the
	 * same callback to all elements in an array, including sub-arrays.
	 *
	 *     // Apply "strip_tags" to every element in the array
	 *     $array = Arr::map('strip_tags', $array);
	 *
	 * [!!] Unlike `array_map`, this method requires a callback and will only map
	 * a single array.
	 *
	 * @param   mixed   callback applied to every element in the array
	 * @param   array   array to map
	 * @return  array
	 */
	public static function map($callback, $array)
	{
		foreach ($array as $key => $val)
		{
			if (is_array($val))
			{
				$array[$key] = Arr::map($callback, $val);
			}
			else
			{
				$array[$key] = call_user_func($callback, $val);
			}
		}

		return $array;
	}

	/**
	 * Merges one or more arrays recursively and preserves all keys.
	 * Note that this does not work the same as [array_merge_recursive](http://php.net/array_merge_recursive)!
	 *
	 *     $john = array('name' => 'john', 'children' => array('fred', 'paul', 'sally', 'jane'));
	 *     $mary = array('name' => 'mary', 'children' => array('jane'));
	 *
	 *     // John and Mary are married, merge them together
	 *     $john = Arr::merge($john, $mary);
	 *
	 *     // The output of $john will now be:
	 *     array('name' => 'mary', 'children' => array('fred', 'paul', 'sally', 'jane'))
	 *
	 * @param   array  initial array
	 * @param   array  array to merge
	 * @param   array  ...
	 * @return  array
	 */
	public static function merge(array $a1, array $a2)
	{
		$result = array();
		for ($i = 0, $total = func_num_args(); $i < $total; $i++)
		{
			// Get the next array
			$arr = func_get_arg($i);

			// Is the array associative?
			$assoc = Arr::is_assoc($arr);

			foreach ($arr as $key => $val)
			{
				if (isset($result[$key]))
				{
					if (is_array($val) AND is_array($result[$key]))
					{
						if (Arr::is_assoc($val))
						{
							// Associative arrays are merged recursively
							$result[$key] = Arr::merge($result[$key], $val);
						}
						else
						{
							// Find the values that are not already present
							$diff = array_diff($val, $result[$key]);

							// Indexed arrays are merged to prevent duplicates
							$result[$key] = array_merge($result[$key], $diff);
						}
					}
					else
					{
						if ($assoc)
						{
							// Associative values are replaced
							$result[$key] = $val;
						}
						elseif ( ! in_array($val, $result, TRUE))
						{
							// Indexed values are added only if they do not yet exist
							$result[] = $val;
						}
					}
				}
				else
				{
					// New values are added
					$result[$key] = $val;
				}
			}
		}

		return $result;
	}

	/**
	 * Overwrites an array with values from input arrays.
	 * Keys that do not exist in the first array will not be added!
	 *
	 *     $a1 = array('name' => 'john', 'mood' => 'happy', 'food' => 'bacon');
	 *     $a2 = array('name' => 'jack', 'food' => 'tacos', 'drink' => 'beer');
	 *
	 *     // Overwrite the values of $a1 with $a2
	 *     $array = Arr::overwrite($a1, $a2);
	 *
	 *     // The output of $array will now be:
	 *     array('name' => 'jack', 'mood' => 'happy', 'food' => 'tacos')
	 *
	 * @param   array   master array
	 * @param   array   input arrays that will overwrite existing values
	 * @return  array
	 */
	public static function overwrite($array1, $array2)
	{
		foreach (array_intersect_key($array2, $array1) as $key => $value)
		{
			$array1[$key] = $value;
		}

		if (func_num_args() > 2)
		{
			foreach (array_slice(func_get_args(), 2) as $array2)
			{
				foreach (array_intersect_key($array2, $array1) as $key => $value)
				{
					$array1[$key] = $value;
				}
			}
		}

		return $array1;
	}

	/**
	 * Creates a callable function and parameter list from a string representation.
	 * Note that this function does not validate the callback string.
	 *
	 *     // Get the callback function and parameters
	 *     list($func, $params) = Arr::callback('Foo::bar(apple,orange)');
	 *
	 *     // Get the result of the callback
	 *     $result = call_user_func_array($func, $params);
	 *
	 * @param   string  callback string
	 * @return  array   function, params
	 */
	public static function callback($str)
	{
		// Overloaded as parts are found
		$command = $params = NULL;

		// command[param,param]
		if (preg_match('/^([^\(]*+)\((.*)\)$/', $str, $match))
		{
			// command
			$command = $match[1];

			if ($match[2] !== '')
			{
				// param,param
				$params = preg_split('/(?<!\\\\),/', $match[2]);
				$params = str_replace('\,', ',', $params);
			}
		}
		else
		{
			// command
			$command = $str;
		}

		if (strpos($command, '::') !== FALSE)
		{
			// Create a static method callable command
			$command = explode('::', $command, 2);
		}

		return array($command, $params);
	}

	/**
	 * Convert a multi-dimensional array into a single-dimensional array.
	 *
	 *     $array = array('set' => array('one' => 'something'), 'two' => 'other');
	 *
	 *     // Flatten the array
	 *     $array = Arr::flatten($array);
	 *
	 *     // The array will now be
	 *     array('one' => 'something', 'two' => 'other');
	 *
	 * [!!] The keys of array values will be discarded.
	 *
	 * @param   array   array to flatten
	 * @return  array
	 * @since   3.0.6
	 */
	public static function flatten($array)
	{
		$flat = array();
		foreach ($array as $key => $value)
		{
			if (is_array($value))
			{
				$flat += Arr::flatten($value);
			}
			else
			{
				$flat[$key] = $value;
			}
		}
		return $flat;
	}

} // End arr
