Complex classes like WordAds_Params often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use WordAds_Params, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 3 | class WordAds_Params { | 
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| 4 | |||
| 5 | /**  | 
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| 6 | * Setup parameters for serving the ads  | 
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| 7 | *  | 
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| 8 | * @since 4.5.0  | 
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| 9 | */  | 
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| 10 | 	public function __construct() { | 
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| 34 | |||
| 35 | /**  | 
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| 36 | * @return boolean true if the user is browsing on a mobile device (iPad not included)  | 
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| 37 | *  | 
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| 38 | * @since 4.5.0  | 
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| 39 | */  | 
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| 40 | 	public function is_mobile() { | 
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| 43 | |||
| 44 | /**  | 
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| 45 | * @return boolean true if site is being served via CloudFlare  | 
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| 46 | *  | 
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| 47 | * @since 4.5.0  | 
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| 48 | */  | 
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| 49 | 	public static function is_cloudflare() { | 
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| 65 | |||
| 66 | /**  | 
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| 67 | * @return boolean true if user is browsing in iOS device  | 
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| 68 | *  | 
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| 69 | * @since 4.5.0  | 
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| 70 | */  | 
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| 71 | 	public function is_ios() { | 
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| 74 | |||
| 75 | /**  | 
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| 76 | * Returns the user's device (see user-agent.php) or 'desktop'  | 
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| 77 | * @return string user device  | 
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| 78 | *  | 
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| 79 | * @since 4.5.0  | 
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| 80 | */  | 
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| 81 | 	public function get_device() { | 
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| 94 | |||
| 95 | /**  | 
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| 96 | * @return string The type of page that is being loaded  | 
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| 97 | *  | 
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| 98 | * @since 4.5.0  | 
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| 99 | */  | 
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| 100 | 	public function get_page_type() { | 
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| 125 | |||
| 126 | /**  | 
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| 127 | * Returns true if page is static home  | 
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| 128 | * @return boolean true if page is static home  | 
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| 129 | *  | 
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| 130 | * @since 4.5.0  | 
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| 131 | */  | 
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| 132 | 	public static function is_static_home() { | 
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| 137 | |||
| 138 | /**  | 
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| 139 | * Logic for if we should show an ad  | 
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| 140 | *  | 
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| 141 | * @since 4.5.0  | 
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| 142 | */  | 
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| 143 | 	public static function should_show() { | 
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| 156 | |||
| 157 | /**  | 
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| 158 | * Logic for if we should show a mobile ad  | 
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| 159 | *  | 
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| 160 | * @since 4.5.0  | 
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| 161 | */  | 
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| 162 | 	public static function should_show_mobile() { | 
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| 179 | }  | 
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| 180 | 
In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code:
Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: