update readme. add a flash tool class.

Author: inhere

LICENSE

@@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2016 inhere
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

README.md

@@ -3,9 +3,9 @@
 - a simple php view renderer, front assets load manage
 - url,html,curl helper class
 
-## usage
+## Usage
 
-### view renderer
+### View renderer
 
 - support layout, data render
 - support simple assets manage and load
@@ -86,3 +86,19 @@ $renderer
 </body>
 </html>
 ```
+
+### Flash Messages
+
+```php
+$flash = new Flash();
+
+// a page
+$flash->warning('page-msg', 'Please login to operate!');
+
+// an other page
+$msg = $flash->get('page-msg');
+```
+
+## license
+
+**[MIT](LICENSE)**

src/Util/Flash.php

@@ -0,0 +1,211 @@
+<?php
+/**
+ * Created by PhpStorm.
+ * User: Inhere
+ * Date: 2018/6/1 0001
+ * Time: 21:19
+ */
+
+namespace Toolkit\Web\Util;
+
+/**
+ * Class Flash
+ * @package Toolkit\Web\Util
+ * @method normal(string $key, string $message, array $opts = [])
+ * @method info(string $key, string $message, array $opts = [])
+ * @method error(string $key, string $message, array $opts = [])
+ * @method danger(string $key, string $message, array $opts = [])
+ * @method success(string $key, string $message, array $opts = [])
+ * @method warning(string $key, string $message, array $opts = [])
+ * @method dark(string $key, string $message, array $opts = [])
+ */
+class Flash
+{
+    // use BootstrapStyleMessageTrait;
+
+    // alert style
+    const LIGHT = 'light';
+    const DARK = 'dark';
+    const INFO = 'info';
+    const SUCCESS = 'success';
+    const PRIMARY = 'primary';
+    const WARN = 'warning';
+    const WARNING = 'warning';
+    const ERROR = 'danger';
+    const DANGER = 'danger';
+    const SECONDARY = 'secondary';
+
+    const SESS_DATA_KEY = '_user_flash_data';
+
+    const FLASH_STYLES = [
+        'normal' => 'secondary',
+        'default' => 'secondary',
+        'primary' => 'primary',
+        'secondary' => 'secondary',
+        'success' => 'success',
+        'error' => 'danger',
+        'danger' => 'danger',
+        'warning' => 'warning',
+        'info' => 'info',
+        'light' => 'light',
+        'dark' => 'dark'
+    ];
+
+    /**
+     * @var string
+     */
+    private $storageKey = self::SESS_DATA_KEY;
+
+    /**
+     * Messages from previous request
+     * @var string[]
+     */
+    protected $previous = [];
+
+    /**
+     * Message storage
+     * @var null|array|\ArrayAccess
+     */
+    protected $storage;
+
+    /**
+     * Flash constructor.
+     * @param null|array|\ArrayAccess $storage
+     * @throws \RuntimeException
+     * @throws \InvalidArgumentException
+     */
+    public function __construct(&$storage = null)
+    {
+        // Set storage
+        if (\is_array($storage) || $storage instanceof \ArrayAccess) {
+            $this->storage = &$storage;
+        } elseif (null === $storage) {
+            if ($_SESSION === null) {
+                throw new \RuntimeException('Flash messages middleware failed. Session not found.');
+            }
+
+            $this->storage = &$_SESSION;
+        } else {
+            throw new \InvalidArgumentException('Flash messages storage must be an array or implement \ArrayAccess');
+        }
+
+        // load previous request messages
+        if ($previous = $this->storage[$this->storageKey] ?? null) {
+            $this->previous = $previous;
+        }
+
+        // clear old, init for current request
+        $this->storage[$this->storageKey] = [];
+    }
+
+    /**
+     * flash message
+     * @param string $key
+     * @param string $message
+     * @param string $style
+     * @param array $opts
+     * [
+     *  'title' => 'custom title',
+     *  'closeable' => 1
+     * ]
+     */
+    public function addMessage(string $key, string $message, string $style = 'info', array $opts = [])
+    {
+        if (!$key || !$message) {
+            return;
+        }
+
+        $body = \array_merge([
+            'closeable' => 1,
+        ], $opts, [
+            'type' => $style,
+            'msg' => $message,
+        ]);
+
+        if (!isset($body['title'])) {
+            $body['title'] = \ucfirst($style);
+        }
+
+        // add message
+        $this->storage[$this->storageKey][$key] = \json_encode($body);
+    }
+
+    /**
+     * flash old request data.
+     * @param string $key
+     * @param array $data
+     */
+    public function save(string $key, array $data)
+    {
+        $this->storage[$this->storageKey][$key] = \json_encode($data);
+    }
+
+    /**
+     * @param string $key
+     * @return null|array
+     */
+    public function get(string $key)
+    {
+        if ($json = $this->previous[$key] ?? null) {
+            return \json_decode($json, true);
+        }
+
+        return null;
+    }
+
+    /**
+     * @param string $key
+     * @return string
+     */
+    public function getMessage(string $key): string
+    {
+        if ($body = $this->get($key)) {
+            return $body['msg'] ?? '';
+        }
+
+        return '';
+    }
+
+    /**
+     * @param string $name style name
+     * @param array $args
+     * @return self
+     * @throws \InvalidArgumentException
+     */
+    public function __call($name, array $args)
+    {
+        if ($style = self::FLASH_STYLES[$name] ?? null) {
+            if (!isset($args[1])) {
+                throw new \InvalidArgumentException('missing enough parameters');
+            }
+
+            $this->addMessage($args[0], $args[1], $style, isset($args[2]) ? (array)$args[2] : []);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @return array
+     */
+    public function getMessages(): array
+    {
+        return $this->storage[$this->storageKey];
+    }
+
+    /**
+     * @return string
+     */
+    public function getStorageKey(): string
+    {
+        return $this->storageKey;
+    }
+
+    /**
+     * @param string $storageKey
+     */
+    public function setStorageKey(string $storageKey)
+    {
+        $this->storageKey = $storageKey;
+    }
+}