DynamicCSSCompiler::get_instance() - Code Metrics - askupasoftware/wp-dynamic-css - Measure and Improve Code Quality continuously with Scrutinizer

DynamicCSSCompiler::get_instance() A
last analyzed 2016-12-25 17:50 UTC

↳ Parent: DynamicCSSCompiler

Complexity

Conditions	2
Paths	2

Size

Total Lines	8
Code Lines	4

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
cc	2
eloc	4
nc	2
nop	0
dl	0
loc	8
rs	9.4285
c	0
b	0
f	0

<?php
/**
 * @package   WordPress Dynamic CSS
 * @version   1.0.5
 * @author    Askupa Software <[email protected]>
 * @link      https://github.com/askupasoftware/wp-dynamic-css
 * @copyright 2016 Askupa Software
 */

/**
 * Dynamic CSS Compiler Utility Class
 * 
 * 
 * Dynamic CSS Syntax
 * ------------------
 * <pre>
 * body {color: $body_color;} 
 * </pre>
 * In the above example, the variable $body_color is replaced by a value 
 * retrieved by the value callback function. The function is passed the variable 
 * name without the dollar sign, which can be used with get_option() or 
 * get_theme_mod() etc.
 */
class DynamicCSSCompiler
namespace YourVendor;

class YourClass { }
{
    /**
     * @var DynamicCSSCompiler The reference to *Singleton* instance of this class
     */
    private static $instance;
    
    /**
     * @var array The list of dynamic styles paths to compile
     */
    private $stylesheets = array();
    
    /**
     * @var array The list of registered callbacks
     */
    private $callbacks = array();
    
    /**
     * @var aray The list of registered filters
     */
    private $filters = array();
    
    /**
     * Returns the *Singleton* instance of this class.
     *
     * @return DynamicCSSCompiler The *Singleton* instance.
     */
    public static function get_instance()
    {
        if (null === static::$instance) 
class YourClass
{
    private static $someVariable;

    public static function getSomeVariable()
    {
        return static::$someVariable;
    }
}
        {
            static::$instance = new static();
class YourClass
{
    private static $someVariable;

    public static function getSomeVariable()
    {
        return static::$someVariable;
    }
}
        }
        return static::$instance;
class YourClass
{
    private static $someVariable;

    public static function getSomeVariable()
    {
        return static::$someVariable;
    }
}
    }
    
    /**
     * Enqueue all registered stylesheets.
     */
    public function enqueue_styles()
    {
        foreach( $this->stylesheets as $stylesheet )
        {
            if( $this->callback_exists( $stylesheet['handle'] ) )
            {
                $this->enqueue_style( $stylesheet );
            }
        }
    }
    
    /**
     * Enqueue a single registered stylesheet.
     * 
     * @param array $stylesheet
     */
    public function enqueue_style( $stylesheet )
    {
        $handle = 'wp-dynamic-css-'.$stylesheet['handle'];
        $print  = $stylesheet['print'];
        
        wp_register_style( 
            $handle,
            // Don't pass a URL if this style is to be printed
            $print ? false : $this->get_ajax_callback_url( $stylesheet['handle'] )
        );

        wp_enqueue_style( $handle );
        
        // Add inline styles for styles that are set to be printed
        if( $print )
        {
            // Inline styles only work if the handle has already been registered and enqueued
            wp_add_inline_style( $handle, $this->get_compiled_style( $stylesheet ) );
        }
    }
    
    /**
     * This is the AJAX callback used for loading styles externally via an http 
     * request.
     */
    public function ajax_callback()
    {
        header( "Content-type: text/css; charset: UTF-8" );
        $handle = filter_input( INPUT_GET, 'handle' );
        
        foreach( $this->stylesheets as $stylesheet )
        {
            if( $handle === $stylesheet['handle'] )
            {
                echo $this->get_compiled_style( $stylesheet );
            }
        }
        
        wp_die();
    }
    
    /**
     * Add a style path to the pool of styles to be compiled
     * 
     * @param string $handle The stylesheet's name/id
     * @param string $path The absolute path to the dynamic style
     * @param boolean $print Whether to print the compiled CSS to the document
     * head, or include it as an external CSS file
     * @param boolean $minify Whether to minify the CSS output
     * @param boolean $cache Whether to store the compiled version of this 
     * stylesheet in cache to avoid compilation on every page load.
     */
    public function register_style( $handle, $path, $print, $minify, $cache )
    {
        $this->stylesheets[] = array(
            'handle'=> $handle,
            'path'  => $path,
            'print' => $print,
            'minify'=> $minify,
            'cache' => $cache
        );
    }
    
    /**
     * Register a value retrieval function and associate it with the given handle
     * 
     * @param string $handle The stylesheet's name/id
     * @param callable $callback
     */
    public function register_callback( $handle, $callback )
    {
        $this->callbacks[$handle] = $callback;
    }
    
    /**
     * Register a filter function for a given stylesheet handle.
     */
    public function register_filter( $handle, $filter_name, $callback )
    {
        if( !array_key_exists( $handle, $this->filters ) )
        {
            $this->filters[$handle] = array();
        }
        $this->filters[$handle][$filter_name] = $callback;
    }
    
    /**
     * Get the compiled CSS for the given style. Skips compilation if the compiled
     * version can be found in cache.
     * 
     * @param array $style List of styles with the same structure as they are 
     * stored in $this->stylesheets
     * @return string The compiled CSS for this stylesheet
     */
    protected function get_compiled_style( $style )
    {
        $cache = DynamicCSSCache::get_instance();
        
        // Use cached compiled CSS if applicable
        if( $style['cache'] )
        {
            $cached_css = $cache->get( $style['handle'] );
            if( false !== $cached_css )
            {
                return $cached_css;
            }
        }

        $css = file_get_contents( $style['path'] );
        if( $style['minify'] ) $css = $this->minify_css( $css );
        
        // Compile the dynamic CSS
        $compiled_css = $this->compile_css( 
            $css, 
            $this->callbacks[$style['handle']], 
            (array) @$this->filters[$style['handle']]
        );
        
        $cache->update( $style['handle'], $compiled_css );
        return $this->add_meta_info( $compiled_css );
    }
    
    /**
     * Add meta information to the compiled CSS
     * 
     * @param string $compiled_css The compiled CSS
     * @return string The compiled CSS with the meta information added to it
     */
    protected function add_meta_info( $compiled_css )
    {
        return "/**\n".
               " * Compiled using wp-dynamic-css\n".
               " * https://github.com/askupasoftware/wp-dynamic-css\n".
               " */\n\n".
               $compiled_css;
    }
    
    /**
     * Get the callback URL for enqueuing the stylesheet extrnally
     * 
     * @param string $handle The stylesheet's handle
     * @return string The URL for the given handle
     */
    protected function get_ajax_callback_url( $handle )
    {
        return esc_url_raw( 
            add_query_arg(array(
                'action' => 'wp_dynamic_css',
                'handle' => $handle
            ), 
            admin_url( 'admin-ajax.php'))
        );
    }
    
    /**
     * Minify a given CSS string by removing comments, whitespaces and newlines
     * 
     * @see http://stackoverflow.com/a/6630103/1096470
     * @param string $css CSS style to minify
     * @return string Minified CSS
     */
    protected function minify_css( $css )
    {
        return preg_replace( '@({)\s+|(\;)\s+|/\*.+?\*\/|\R@is', '$1$2 ', $css );
    }
    
    /**
     * Check if a callback function has been register for the given handle.
     * 
     * @param string $handle 
     * @return boolean
     */
    protected function callback_exists( $handle )
    {
        if( array_key_exists( $handle, $this->callbacks ) )
        {
            return true;
        }
        trigger_error( 
            "There is no callback function associated with the handle '$handle'. ".
            "Use <b>wp_dynamic_css_set_callback()</b> to register a callback function for this handle." 
        );
        return false;
    }
    
    /**
     * Parse the given CSS string by converting the variables to their 
     * corresponding values retrieved by applying the callback function
     * 
     * @param callable $callback A function that replaces the variables with 
     * their values. The function accepts the variable's name as a parameter
     * @param string $css A string containing dynamic CSS (pre-compiled CSS with 
     * variables)
     * @return string The compiled CSS after converting the variables to their 
     * corresponding values
     */
    protected function compile_css( $css, $callback, $filters )
    {
        return preg_replace_callback( 
                
            "#".                        // Begin
            "\\$".                      // Must start with $
            "([\\w-]+)".                // Match alphanumeric characters and dashes
            "((?:\\['?[\\w-]+'?\\])*)". // Optionally match array subscripts i.e. $myVar['index']
            "((?:".                     // Optionally match pipe filters i.e. $myVar|myFilter
                "\\|[\\w-]+".           // Starting with the | character
                "(\([\w\.,']+\))?".     // Filters can have strings and numbers i.e myFilter('string',1,2.5)
            ")*)".                      // Allow for 0 or more piped filters
            "#",                        // End
            
            function( $matches ) use ( $callback, $filters ) 
            {
                $subscripts = array();
                
                // If this variable is an array, get the subscripts
                if( '' !== $matches[2] )
                {
                    preg_match_all('/[\w-]+/i', $matches[2], $subscripts);
                }
                
                $val = call_user_func_array( $callback, array( $matches[1],@$subscripts[0] ) );
                
                // If there are filters, apply them
                if( '' !== $matches[3] )
                {
                    $val = $this->apply_filters( substr( $matches[3], 1 ), $val, $filters );
                }
                
                return $val;
            }, $css
        );
    }
    
    /**
     * Apply the filters specified in $filters_string to the given $value.
     * 
     * @param string $filters_string 
     * @param string $value
     * @param array $filters Array of callback functions
     * @return string The value after all filters have been applied
     */
    protected function apply_filters( $filters_string, $value, $filters = array() )
    {
        foreach( explode( '|', $filters_string) as $filter )
        {
            $args = array( $value );
            
            if( false !== strrpos( $filters_string, "(" ) )
            {
                $pieces = explode( '(', $filter );
                $filter = $pieces[0];
                $params = explode( ',', str_replace( ')', '', $pieces[1] ) );
                array_walk( $params, array( $this, 'strtoval' ) ); // Convert string values to actual values
                $args = array_merge( $args, $params );
            }
            
            if( key_exists( $filter, $filters ) )
            {
                $value = call_user_func_array( $filters[$filter], $args );
            }
        }
        return $value;
    }
    
    /**
     * Convert the given string to its actual value.
     * 
     * @param string $str The string to be converted (passed by reference)
     */
    protected function strtoval( &$str )
    {
        if( 'false' === strtolower($str) ) $str = false;
        if( 'true' === strtolower($str) ) $str = true;
        if( false !== strrpos( $str, "'" ) ) $str = str_replace ( "'", "", $str );
        if( is_numeric( $str ) ) $str = floatval( $str );
    }
}


1			<?php
2			/**
3			* @package WordPress Dynamic CSS
4			* @version 1.0.5
5			* @author Askupa Software <[email protected]>
6			* @link https://github.com/askupasoftware/wp-dynamic-css
7			* @copyright 2016 Askupa Software
8			*/
9
10			/**
11			* Dynamic CSS Compiler Utility Class
12			*
13			*
14			* Dynamic CSS Syntax
15			* ------------------
16			* <pre>
17			* body {color: $body_color;}
18			* </pre>
19			* In the above example, the variable $body_color is replaced by a value
20			* retrieved by the value callback function. The function is passed the variable
21			* name without the dollar sign, which can be used with get_option() or
22			* get_theme_mod() etc.
23			*/
24			class DynamicCSSCompiler
			0 ignored issues – show Coding Style Compatibility introduced 2016-03-20 06:18 UTC by Report Bug Copy Issue Report PSR1 recommends that each class must be in a namespace of at least one level to avoid collisions. You can fix this by adding a namespace to your class: namespace YourVendor; class YourClass { } When choosing a vendor namespace, try to pick something that is not too generic to avoid conflicts with other libraries. Loading history...
25			{
26			/**
27			* @var DynamicCSSCompiler The reference to Singleton instance of this class
28			*/
29			private static $instance;
30
31			/**
32			* @var array The list of dynamic styles paths to compile
33			*/
34			private $stylesheets = array();
35
36			/**
37			* @var array The list of registered callbacks
38			*/
39			private $callbacks = array();
40
41			/**
42			* @var aray The list of registered filters
43			*/
44			private $filters = array();
45
46			/**
47			* Returns the Singleton instance of this class.
48			*
49			* @return DynamicCSSCompiler The Singleton instance.
50			*/
51			public static function get_instance()
52			{
53			if (null === static::$instance)
			0 ignored issues – show Bug introduced 2016-03-20 04:49 UTC by Report Bug Copy Issue Report Since `$instance` is declared private, accessing it with `static` will lead to errors in possible sub-classes; consider using `self`, or increasing the visibility of `$instance` to at least protected. Let’s assume you have a class which uses late-static binding: class YourClass { private static $someVariable; public static function getSomeVariable() { return static::$someVariable; } } The code above will run fine in your PHP runtime. However, if you now create a sub-class and call the `getSomeVariable()` on that sub-class, you will receive a runtime error: class YourSubClass extends YourClass { } YourSubClass::getSomeVariable(); // Will cause an access error. In the case above, it makes sense to update `SomeClass` to use `self` instead: class SomeClass { private static $someVariable; public static function getSomeVariable() { return self::$someVariable; // self works fine with private. } } Loading history...
54			{
55			static::$instance = new static();
			0 ignored issues – show Bug introduced 2016-03-20 04:49 UTC by Report Bug Copy Issue Report Since `$instance` is declared private, accessing it with `static` will lead to errors in possible sub-classes; consider using `self`, or increasing the visibility of `$instance` to at least protected. Let’s assume you have a class which uses late-static binding: class YourClass { private static $someVariable; public static function getSomeVariable() { return static::$someVariable; } } The code above will run fine in your PHP runtime. However, if you now create a sub-class and call the `getSomeVariable()` on that sub-class, you will receive a runtime error: class YourSubClass extends YourClass { } YourSubClass::getSomeVariable(); // Will cause an access error. In the case above, it makes sense to update `SomeClass` to use `self` instead: class SomeClass { private static $someVariable; public static function getSomeVariable() { return self::$someVariable; // self works fine with private. } } Loading history...
56			}
57			return static::$instance;
			0 ignored issues – show Bug introduced 2016-03-20 04:49 UTC by Report Bug Copy Issue Report Since `$instance` is declared private, accessing it with `static` will lead to errors in possible sub-classes; consider using `self`, or increasing the visibility of `$instance` to at least protected. Let’s assume you have a class which uses late-static binding: class YourClass { private static $someVariable; public static function getSomeVariable() { return static::$someVariable; } } The code above will run fine in your PHP runtime. However, if you now create a sub-class and call the `getSomeVariable()` on that sub-class, you will receive a runtime error: class YourSubClass extends YourClass { } YourSubClass::getSomeVariable(); // Will cause an access error. In the case above, it makes sense to update `SomeClass` to use `self` instead: class SomeClass { private static $someVariable; public static function getSomeVariable() { return self::$someVariable; // self works fine with private. } } Loading history...
58			}
59
60			/**
61			* Enqueue all registered stylesheets.
62			*/
63			public function enqueue_styles()
64			{
65			foreach( $this->stylesheets as $stylesheet )
66			{
67			if( $this->callback_exists( $stylesheet['handle'] ) )
68			{
69			$this->enqueue_style( $stylesheet );
70			}
71			}
72			}
73
74			/**
75			* Enqueue a single registered stylesheet.
76			*
77			* @param array $stylesheet
78			*/
79			public function enqueue_style( $stylesheet )
80			{
81			$handle = 'wp-dynamic-css-'.$stylesheet['handle'];
82			$print = $stylesheet['print'];
83
84			wp_register_style(
85			$handle,
86			// Don't pass a URL if this style is to be printed
87			$print ? false : $this->get_ajax_callback_url( $stylesheet['handle'] )
88			);
89
90			wp_enqueue_style( $handle );
91
92			// Add inline styles for styles that are set to be printed
93			if( $print )
94			{
95			// Inline styles only work if the handle has already been registered and enqueued
96			wp_add_inline_style( $handle, $this->get_compiled_style( $stylesheet ) );
97			}
98			}
99
100			/**
101			* This is the AJAX callback used for loading styles externally via an http
102			* request.
103			*/
104			public function ajax_callback()
105			{
106			header( "Content-type: text/css; charset: UTF-8" );
107			$handle = filter_input( INPUT_GET, 'handle' );
108
109			foreach( $this->stylesheets as $stylesheet )
110			{
111			if( $handle === $stylesheet['handle'] )
112			{
113			echo $this->get_compiled_style( $stylesheet );
114			}
115			}
116
117			wp_die();
118			}
119
120			/**
121			* Add a style path to the pool of styles to be compiled
122			*
123			* @param string $handle The stylesheet's name/id
124			* @param string $path The absolute path to the dynamic style
125			* @param boolean $print Whether to print the compiled CSS to the document
126			* head, or include it as an external CSS file
127			* @param boolean $minify Whether to minify the CSS output
128			* @param boolean $cache Whether to store the compiled version of this
129			* stylesheet in cache to avoid compilation on every page load.
130			*/
131			public function register_style( $handle, $path, $print, $minify, $cache )
132			{
133			$this->stylesheets[] = array(
134			'handle'=> $handle,
135			'path' => $path,
136			'print' => $print,
137			'minify'=> $minify,
138			'cache' => $cache
139			);
140			}
141
142			/**
143			* Register a value retrieval function and associate it with the given handle
144			*
145			* @param string $handle The stylesheet's name/id
146			* @param callable $callback
147			*/
148			public function register_callback( $handle, $callback )
149			{
150			$this->callbacks[$handle] = $callback;
151			}
152
153			/**
154			* Register a filter function for a given stylesheet handle.
155			*/
156			public function register_filter( $handle, $filter_name, $callback )
157			{
158			if( !array_key_exists( $handle, $this->filters ) )
159			{
160			$this->filters[$handle] = array();
161			}
162			$this->filters[$handle][$filter_name] = $callback;
163			}
164
165			/**
166			* Get the compiled CSS for the given style. Skips compilation if the compiled
167			* version can be found in cache.
168			*
169			* @param array $style List of styles with the same structure as they are
170			* stored in $this->stylesheets
171			* @return string The compiled CSS for this stylesheet
172			*/
173			protected function get_compiled_style( $style )
174			{
175			$cache = DynamicCSSCache::get_instance();
176
177			// Use cached compiled CSS if applicable
178			if( $style['cache'] )
179			{
180			$cached_css = $cache->get( $style['handle'] );
181			if( false !== $cached_css )
182			{
183			return $cached_css;
184			}
185			}
186
187			$css = file_get_contents( $style['path'] );
188			if( $style['minify'] ) $css = $this->minify_css( $css );
189
190			// Compile the dynamic CSS
191			$compiled_css = $this->compile_css(
192			$css,
193			$this->callbacks[$style['handle']],
194			(array) @$this->filters[$style['handle']]
195			);
196
197			$cache->update( $style['handle'], $compiled_css );
198			return $this->add_meta_info( $compiled_css );
199			}
200
201			/**
202			* Add meta information to the compiled CSS
203			*
204			* @param string $compiled_css The compiled CSS
205			* @return string The compiled CSS with the meta information added to it
206			*/
207			protected function add_meta_info( $compiled_css )
208			{
209			return "/**\n".
210			" * Compiled using wp-dynamic-css\n".
211			" * https://github.com/askupasoftware/wp-dynamic-css\n".
212			" */\n\n".
213			$compiled_css;
214			}
215
216			/**
217			* Get the callback URL for enqueuing the stylesheet extrnally
218			*
219			* @param string $handle The stylesheet's handle
220			* @return string The URL for the given handle
221			*/
222			protected function get_ajax_callback_url( $handle )
223			{
224			return esc_url_raw(
225			add_query_arg(array(
226			'action' => 'wp_dynamic_css',
227			'handle' => $handle
228			),
229			admin_url( 'admin-ajax.php'))
230			);
231			}
232
233			/**
234			* Minify a given CSS string by removing comments, whitespaces and newlines
235			*
236			* @see http://stackoverflow.com/a/6630103/1096470
237			* @param string $css CSS style to minify
238			* @return string Minified CSS
239			*/
240			protected function minify_css( $css )
241			{
242			return preg_replace( '@({)\s+\|(\;)\s+\|/\.+?\\/\|\R@is', '$1$2 ', $css );
243			}
244
245			/**
246			* Check if a callback function has been register for the given handle.
247			*
248			* @param string $handle
249			* @return boolean
250			*/
251			protected function callback_exists( $handle )
252			{
253			if( array_key_exists( $handle, $this->callbacks ) )
254			{
255			return true;
256			}
257			trigger_error(
258			"There is no callback function associated with the handle '$handle'. ".
259			"Use <b>wp_dynamic_css_set_callback()</b> to register a callback function for this handle."
260			);
261			return false;
262			}
263
264			/**
265			* Parse the given CSS string by converting the variables to their
266			* corresponding values retrieved by applying the callback function
267			*
268			* @param callable $callback A function that replaces the variables with
269			* their values. The function accepts the variable's name as a parameter
270			* @param string $css A string containing dynamic CSS (pre-compiled CSS with
271			* variables)
272			* @return string The compiled CSS after converting the variables to their
273			* corresponding values
274			*/
275			protected function compile_css( $css, $callback, $filters )
276			{
277			return preg_replace_callback(
278
279			"#". // Begin
280			"\\$". // Must start with $
281			"([\\w-]+)". // Match alphanumeric characters and dashes
282			"((?:\\['?[\\w-]+'?\\])*)". // Optionally match array subscripts i.e. $myVar['index']
283			"((?:". // Optionally match pipe filters i.e. $myVar\|myFilter
284			"\\\|[\\w-]+". // Starting with the \| character
285			"(\([\w\.,']+\))?". // Filters can have strings and numbers i.e myFilter('string',1,2.5)
286			")*)". // Allow for 0 or more piped filters
287			"#", // End
288
289			function( $matches ) use ( $callback, $filters )
290			{
291			$subscripts = array();
292
293			// If this variable is an array, get the subscripts
294			if( '' !== $matches[2] )
295			{
296			preg_match_all('/[\w-]+/i', $matches[2], $subscripts);
297			}
298
299			$val = call_user_func_array( $callback, array( $matches[1],@$subscripts[0] ) );
300
301			// If there are filters, apply them
302			if( '' !== $matches[3] )
303			{
304			$val = $this->apply_filters( substr( $matches[3], 1 ), $val, $filters );
305			}
306
307			return $val;
308			}, $css
309			);
310			}
311
312			/**
313			* Apply the filters specified in $filters_string to the given $value.
314			*
315			* @param string $filters_string
316			* @param string $value
317			* @param array $filters Array of callback functions
318			* @return string The value after all filters have been applied
319			*/
320			protected function apply_filters( $filters_string, $value, $filters = array() )
321			{
322			foreach( explode( '\|', $filters_string) as $filter )
323			{
324			$args = array( $value );
325
326			if( false !== strrpos( $filters_string, "(" ) )
327			{
328			$pieces = explode( '(', $filter );
329			$filter = $pieces[0];
330			$params = explode( ',', str_replace( ')', '', $pieces[1] ) );
331			array_walk( $params, array( $this, 'strtoval' ) ); // Convert string values to actual values
332			$args = array_merge( $args, $params );
333			}
334
335			if( key_exists( $filter, $filters ) )
336			{
337			$value = call_user_func_array( $filters[$filter], $args );
338			}
339			}
340			return $value;
341			}
342
343			/**
344			* Convert the given string to its actual value.
345			*
346			* @param string $str The string to be converted (passed by reference)
347			*/
348			protected function strtoval( &$str )
349			{
350			if( 'false' === strtolower($str) ) $str = false;
351			if( 'true' === strtolower($str) ) $str = true;
352			if( false !== strrpos( $str, "'" ) ) $str = str_replace ( "'", "", $str );
353			if( is_numeric( $str ) ) $str = floatval( $str );
354			}
355			}
356

askupasoftware / wp-dynamic-css

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DynamicCSSCompiler::get_instance() A last analyzed 2016-12-25 17:50 UTC

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DynamicCSSCompiler::get_instance() A
last analyzed 2016-12-25 17:50 UTC