<?php
namespace Kant\Support;

use ArrayAccess;

class Arr
{

    /**
     * Determine whether the given value is array accessible.
     *
     * @param mixed $value            
     * @return bool
     */
    public static function accessible($value)
    {
        return is_array($value) || $value instanceof ArrayAccess;
    }

    /**
     * Add an element to an array using "dot" notation if it doesn't exist.
     *
     * @param array $array            
     * @param string $key            
     * @param mixed $value            
     * @return array
     */
    public static function add($array, $key, $value)
    {
        if (is_null(static::get($array, $key))) {
            static::set($array, $key, $value);
        }
        
        return $array;
    }

    /**
     * Build a new array using a callback.
     *
     * @param array $array            
     * @param callable $callback            
     * @return array
     *
     * @deprecated since version 5.2.
     */
    public static function build($array, callable $callback)
    {
        $results = [];
        
        foreach ($array as $key => $value) {
            list ($innerKey, $innerValue) = call_user_func($callback, $key, $value);
            
            $results[$innerKey] = $innerValue;
        }
        
        return $results;
    }

    /**
     * Collapse an array of arrays into a single array.
     *
     * @param array $array            
     * @return array
     */
    public static function collapse($array)
    {
        $results = [];
        
        foreach ($array as $values) {
            if ($values instanceof Collection) {
                $values = $values->all();
            } elseif (!is_array($values)) {
                continue;
            }
            
            $results = array_merge($results, $values);
        }
        
        return $results;
    }

    /**
     * Divide an array into two arrays.
     * One with keys and the other with values.
     *
     * @param array $array            
     * @return array
     */
    public static function divide($array)
    {
        return [
            array_keys($array),
            array_values($array)
        ];
    }

    /**
     * Flatten a multi-dimensional associative array with dots.
     *
     * @param array $array            
     * @param string $prepend            
     * @return array
     */
    public static function dot($array, $prepend = '')
    {
        $results = [];
        
        foreach ($array as $key => $value) {
            if (is_array($value)) {
                $results = array_merge($results, static::dot($value, $prepend . $key . '.'));
            } else {
                $results[$prepend . $key] = $value;
            }
        }
        
        return $results;
    }

    /**
     * Get all of the given array except for a specified array of items.
     *
     * @param array $array            
     * @param array|string $keys            
     * @return array
     */
    public static function except($array, $keys)
    {
        static::forget($array, $keys);
        
        return $array;
    }

    /**
     * Determine if the given key exists in the provided array.
     *
     * @param \ArrayAccess|array $array            
     * @param string|int $key            
     * @return bool
     */
    public static function exists($array, $key)
    {
        if ($array instanceof ArrayAccess) {
            return $array->offsetExists($key);
        }
        
        return array_key_exists($key, $array);
    }

    /**
     * Return the first element in an array passing a given truth test.
     *
     * @param array $array            
     * @param callable|null $callback            
     * @param mixed $default            
     * @return mixed
     */
    public static function first($array, callable $callback = null, $default = null)
    {
        if (is_null($callback)) {
            if (empty($array)) {
                return value($default);
            }
            
            foreach ($array as $item) {
                return $item;
            }
        }
        
        foreach ($array as $key => $value) {
            if (call_user_func($callback, $value, $key)) {
                return $value;
            }
        }
        
        return value($default);
    }

    /**
     * Return the last element in an array passing a given truth test.
     *
     * @param array $array            
     * @param callable|null $callback            
     * @param mixed $default            
     * @return mixed
     */
    public static function last($array, callable $callback = null, $default = null)
    {
        if (is_null($callback)) {
            return empty($array) ? value($default) : end($array);
        }
        
        return static::first(array_reverse($array), $callback, $default);
    }

    /**
     * Flatten a multi-dimensional array into a single level.
     *
     * @param array $array            
     * @param int $depth            
     * @return array
     */
    public static function flatten($array, $depth = INF)
    {
        $result = [];
        
        foreach ($array as $item) {
            $item = $item instanceof Collection ? $item->all() : $item;
            
            if (is_array($item)) {
                if ($depth === 1) {
                    $result = array_merge($result, $item);
                    continue;
                }
                
                $result = array_merge($result, static::flatten($item, $depth - 1));
                continue;
            }
            
            $result[] = $item;
        }
        
        return $result;
    }

    /**
     * Remove one or many array items from a given array using "dot" notation.
     *
     * @param array $array            
     * @param array|string $keys            
     * @return void
     */
    public static function forget(&$array, $keys)
    {
        $original = &$array;
        
        $keys = (array) $keys;
        
        if (count($keys) === 0) {
            return;
        }
        
        foreach ($keys as $key) {
            $parts = explode('.', $key);
            
            // clean up before each pass
            $array = &$original;
            
            while (count($parts) > 1) {
                $part = array_shift($parts);
                
                if (isset($array[$part]) && is_array($array[$part])) {
                    $array = &$array[$part];
                } else {
                    continue 2;
                }
            }
            
            unset($array[array_shift($parts)]);
        }
    }

    /**
     * Get an item from an array using "dot" notation.
     *
     * @param \ArrayAccess|array $array            
     * @param string $key            
     * @param mixed $default            
     * @return mixed
     */
    public static function get($array, $key, $default = null)
    {
        if (!static::accessible($array)) {
            return value($default);
        }
        
        if (is_null($key)) {
            return $array;
        }
        
        if (static::exists($array, $key)) {
            return $array[$key];
        }
        
        foreach (explode('.', $key) as $segment) {
            if (static::accessible($array) && static::exists($array, $segment)) {
                $array = $array[$segment];
            } else {
                return value($default);
            }
        }
        
        return $array;
    }

    /**
     * Check if an item exists in an array using "dot" notation.
     *
     * @param \ArrayAccess|array $array            
     * @param string $key            
     * @return bool
     */
    public static function has($array, $key)
    {
        if (!$array) {
            return false;
        }
        
        if (is_null($key)) {
            return false;
        }
        
        if (static::exists($array, $key)) {
            return true;
        }
        
        foreach (explode('.', $key) as $segment) {
            if (static::accessible($array) && static::exists($array, $segment)) {
                $array = $array[$segment];
            } else {
                return false;
            }
        }
        
        return true;
    }

    /**
     * Determines if an array is associative.
     *
     * An array is "associative" if it doesn't have sequential numerical keys beginning with zero.
     *
     * @param array $array            
     * @return bool
     */
    public static function isAssoc(array $array)
    {
        $keys = array_keys($array);
        
        return array_keys($keys) !== $keys;
    }

    /**
     * Get a subset of the items from the given array.
     *
     * @param array $array            
     * @param array|string $keys            
     * @return array
     */
    public static function only($array, $keys)
    {
        return array_intersect_key($array, array_flip((array) $keys));
    }

    /**
     * Pluck an array of values from an array.
     *
     * @param array $array            
     * @param string|array $value            
     * @param string|array|null $key            
     * @return array
     */
    public static function pluck($array, $value, $key = null)
    {
        $results = [];
        
        list ($value, $key) = static::explodePluckParameters($value, $key);
        
        foreach ($array as $item) {
            $itemValue = data_get($item, $value);
            
            // If the key is "null", we will just append the value to the array and keep
            // looping. Otherwise we will key the array using the value of the key we
            // received from the developer. Then we'll return the final array form.
            if (is_null($key)) {
                $results[] = $itemValue;
            } else {
                $itemKey = data_get($item, $key);
                
                $results[$itemKey] = $itemValue;
            }
        }
        
        return $results;
    }

    /**
     * Explode the "value" and "key" arguments passed to "pluck".
     *
     * @param string|array $value            
     * @param string|array|null $key            
     * @return array
     */
    protected static function explodePluckParameters($value, $key)
    {
        $value = is_string($value) ? explode('.', $value) : $value;
        
        $key = is_null($key) || is_array($key) ? $key : explode('.', $key);
        
        return [
            $value,
            $key
        ];
    }

    /**
     * Push an item onto the beginning of an array.
     *
     * @param array $array            
     * @param mixed $value            
     * @param mixed $key            
     * @return array
     */
    public static function prepend($array, $value, $key = null)
    {
        if (is_null($key)) {
            array_unshift($array, $value);
        } else {
            $array = [
                $key => $value
            ] + $array;
        }
        
        return $array;
    }

    /**
     * Get a value from the array, and remove it.
     *
     * @param array $array            
     * @param string $key            
     * @param mixed $default            
     * @return mixed
     */
    public static function pull(&$array, $key, $default = null)
    {
        $value = static::get($array, $key, $default);
        
        static::forget($array, $key);
        
        return $value;
    }

    /**
     * Set an array item to a given value using "dot" notation.
     *
     * If no key is given to the method, the entire array will be replaced.
     *
     * @param array $array            
     * @param string $key            
     * @param mixed $value            
     * @return array
     */
    public static function set(&$array, $key, $value)
    {
        if (is_null($key)) {
            return $array = $value;
        }
        
        $keys = explode('.', $key);
        
        while (count($keys) > 1) {
            $key = array_shift($keys);
            
            // If the key doesn't exist at this depth, we will just create an empty array
            // to hold the next value, allowing us to create the arrays to hold final
            // values at the correct depth. Then we'll keep digging into the array.
            if (!isset($array[$key]) || ! is_array($array[$key])) {
                $array[$key] = [];
            }
            
            $array = &$array[$key];
        }
        
        $array[array_shift($keys)] = $value;
        
        return $array;
    }

    /**
     * Sort the array using the given callback.
     *
     * @param array $array            
     * @param callable $callback            
     * @return array
     */
    public static function sort($array, callable $callback)
    {
        return Collection::make($array)->sortBy($callback)->all();
    }

    /**
     * Recursively sort an array by keys and values.
     *
     * @param array $array            
     * @return array
     */
    public static function sortRecursive($array)
    {
        foreach ($array as &$value) {
            if (is_array($value)) {
                $value = static::sortRecursive($value);
            }
        }
        
        if (static::isAssoc($array)) {
            ksort($array);
        } else {
            sort($array);
        }
        
        return $array;
    }

    /**
     * Filter the array using the given callback.
     *
     * @param array $array            
     * @param callable $callback            
     * @return array
     */
    public static function where($array, callable $callback)
    {
        $filtered = [];
        
        foreach ($array as $key => $value) {
            if (call_user_func($callback, $key, $value)) {
                $filtered[$key] = $value;
            }
        }
        
        return $filtered;
    }
}
