Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like Jetpack_Gutenberg 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 Jetpack_Gutenberg, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
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| 55 | class Jetpack_Gutenberg { | 
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| 56 | |||
| 57 | /**  | 
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| 58 | * Only these extensions can be registered. Used to control availability of beta blocks.  | 
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| 59 | *  | 
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| 60 | * @var array Extensions whitelist  | 
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| 61 | */  | 
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| 62 | private static $extensions = array();  | 
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| 63 | |||
| 64 | /**  | 
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| 65 | * Keeps track of the reasons why a given extension is unavailable.  | 
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| 66 | *  | 
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| 67 | * @var array Extensions availability information  | 
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| 68 | */  | 
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| 69 | private static $availability = array();  | 
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| 70 | |||
| 71 | /**  | 
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| 72 | * Since there is no `register_plugin()` counterpart to `register_block_type()` in Gutenberg,  | 
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| 73 | * we have to keep track of plugin registration ourselves  | 
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| 74 | *  | 
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| 75 | * @var array Plugin registry  | 
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| 76 | */  | 
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| 77 | private static $registered_plugins = array();  | 
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| 78 | |||
| 79 | /**  | 
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| 80 | * Prepend the 'jetpack/' prefix to a block name  | 
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| 81 | *  | 
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| 82 | * @param string $block_name The block name.  | 
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| 83 | *  | 
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| 84 | * @return string The prefixed block name.  | 
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| 85 | */  | 
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| 86 | 	private static function prepend_block_prefix( $block_name ) { | 
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| 87 | return 'jetpack/' . $block_name;  | 
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| 88 | }  | 
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| 89 | |||
| 90 | /**  | 
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| 91 | * Whether two arrays share at least one item  | 
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| 92 | *  | 
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| 93 | * @param array $a An array.  | 
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| 94 | * @param array $b Another array.  | 
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| 95 | *  | 
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| 96 | * @return boolean True if $a and $b share at least one item  | 
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| 97 | */  | 
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| 98 | 	protected static function share_items( $a, $b ) { | 
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| 99 | return count( array_intersect( $a, $b ) ) > 0;  | 
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| 100 | }  | 
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| 101 | |||
| 102 | /**  | 
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| 103 | * Register a block  | 
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| 104 | *  | 
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| 105 | * If the block isn't whitelisted, set its unavailability reason instead.  | 
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| 106 | *  | 
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| 107 | * @param string $slug Slug of the block.  | 
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| 108 | * @param array $args Arguments that are passed into register_block_type().  | 
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| 109 | */  | 
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| 110 | 	public static function register_block( $slug, $args ) { | 
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| 111 | $prefixed_extensions = array_map( array( __CLASS__, 'prepend_block_prefix' ), self::$extensions );  | 
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| 112 | |||
| 113 | // Register the block if it's whitelisted, or if it's a child block, and one of its parents is whitelisted.  | 
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| 114 | 		if ( in_array( $slug, self::$extensions, true ) || ( isset( $args['parent'] ) && self::share_items( $args['parent'], $prefixed_extensions ) ) ) { | 
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| 115 | register_block_type( 'jetpack/' . $slug, $args );  | 
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| 116 | 		} elseif ( ! isset( $args['parent'] ) ) { | 
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| 117 | // Don't set availability information for child blocks -- we infer it from their parents.  | 
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| 118 | self::set_extension_unavailability_reason( $slug, 'not_whitelisted' );  | 
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| 119 | }  | 
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| 120 | }  | 
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| 121 | |||
| 122 | /**  | 
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| 123 | * Register a plugin  | 
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| 124 | *  | 
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| 125 | * If the plugin isn't whitelisted, set its unavailability reason instead.  | 
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| 126 | *  | 
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| 127 | * @param string $slug Slug of the plugin.  | 
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| 128 | */  | 
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| 129 | 	public static function register_plugin( $slug ) { | 
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| 130 | 		if ( in_array( $slug, self::$extensions, true ) ) { | 
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| 131 | self::$registered_plugins[] = 'jetpack-' . $slug;  | 
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| 132 | 		} else { | 
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| 133 | self::set_extension_unavailability_reason( $slug, 'not_whitelisted' );  | 
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| 134 | }  | 
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| 135 | }  | 
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| 136 | |||
| 137 | /**  | 
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| 138 | * Register a block  | 
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| 139 | *  | 
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| 140 | * @deprecated 7.0.0 Use register_block() instead  | 
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| 141 | *  | 
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| 142 | * @param string $slug Slug of the block.  | 
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| 143 | * @param array $args Arguments that are passed into the register_block_type.  | 
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| 144 | * @param array $availability array containing if a block is available and the reason when it is not.  | 
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| 145 | */  | 
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| 146 | 	public static function register( $slug, $args, $availability ) { | 
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| 147 | 		if ( isset( $availability['available'] ) && ! $availability['available'] ) { | 
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| 148 | self::set_extension_unavailability_reason( $slug, $availability['unavailable_reason'] );  | 
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| 149 | 		} else { | 
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| 150 | self::register_block( $slug, $args );  | 
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| 151 | }  | 
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| 152 | }  | 
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| 153 | |||
| 154 | /**  | 
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| 155 | * Set the reason why an extension (block or plugin) is unavailable  | 
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| 156 | *  | 
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| 157 | * @param string $slug Slug of the extension.  | 
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| 158 | * @param string $reason A string representation of why the extension is unavailable.  | 
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| 159 | */  | 
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| 160 | 	public static function set_extension_unavailability_reason( $slug, $reason ) { | 
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| 161 | self::$availability[ $slug ] = $reason;  | 
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| 162 | }  | 
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| 163 | |||
| 164 | /**  | 
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| 165 | * Set up a whitelist of allowed block editor extensions  | 
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| 166 | *  | 
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| 167 | * @return void  | 
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| 168 | */  | 
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| 169 | 	public static function init() { | 
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| 170 | 		if ( ! self::is_gutenberg_available() ) { | 
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| 171 | return;  | 
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| 172 | }  | 
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| 173 | |||
| 174 | 		if ( ! self::should_load() ) { | 
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| 175 | return;  | 
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| 176 | }  | 
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| 177 | |||
| 178 | /**  | 
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| 179 | * Alternative to `JETPACK_BETA_BLOCKS`, set to `true` to load Beta Blocks.  | 
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| 180 | *  | 
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| 181 | * @since 6.9.0  | 
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| 182 | *  | 
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| 183 | * @param boolean  | 
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| 184 | */  | 
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| 185 | 		if ( apply_filters( 'jetpack_load_beta_blocks', false ) ) { | 
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| 186 | Jetpack_Constants::set_constant( 'JETPACK_BETA_BLOCKS', true );  | 
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| 187 | }  | 
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| 188 | |||
| 189 | /**  | 
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| 190 | * Filter the whitelist of block editor extensions that are available through Jetpack.  | 
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| 191 | *  | 
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| 192 | * @since 7.0.0  | 
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| 193 | *  | 
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| 194 | * @param array  | 
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| 195 | */  | 
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| 196 | self::$extensions = apply_filters( 'jetpack_set_available_extensions', self::get_jetpack_gutenberg_extensions_whitelist() );  | 
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| 197 | |||
| 198 | /**  | 
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| 199 | * Filter the whitelist of block editor plugins that are available through Jetpack.  | 
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| 200 | *  | 
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| 201 | * @deprecated 7.0.0 Use jetpack_set_available_extensions instead  | 
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| 202 | *  | 
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| 203 | * @since 6.8.0  | 
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| 204 | *  | 
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| 205 | * @param array  | 
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| 206 | */  | 
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| 207 | self::$extensions = apply_filters( 'jetpack_set_available_blocks', self::$extensions );  | 
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| 208 | |||
| 209 | /**  | 
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| 210 | * Filter the whitelist of block editor plugins that are available through Jetpack.  | 
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| 211 | *  | 
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| 212 | * @deprecated 7.0.0 Use jetpack_set_available_extensions instead  | 
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| 213 | *  | 
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| 214 | * @since 6.9.0  | 
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| 215 | *  | 
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| 216 | * @param array  | 
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| 217 | */  | 
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| 218 | self::$extensions = apply_filters( 'jetpack_set_available_plugins', self::$extensions );  | 
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| 219 | }  | 
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| 220 | |||
| 221 | /**  | 
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| 222 | * Resets the class to its original state  | 
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| 223 | *  | 
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| 224 | * Used in unit tests  | 
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| 225 | *  | 
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| 226 | * @return void  | 
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| 227 | */  | 
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| 228 | 	public static function reset() { | 
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| 229 | self::$extensions = array();  | 
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| 230 | self::$availability = array();  | 
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| 231 | self::$registered_plugins = array();  | 
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| 232 | }  | 
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| 233 | |||
| 234 | /**  | 
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| 235 | * Return the Gutenberg extensions (blocks and plugins) directory  | 
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| 236 | *  | 
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| 237 | * @return string The Gutenberg extensions directory  | 
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| 238 | */  | 
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| 239 | 	public static function get_blocks_directory() { | 
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| 240 | /**  | 
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| 241 | * Filter to select Gutenberg blocks directory  | 
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| 242 | *  | 
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| 243 | * @since 6.9.0  | 
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| 244 | *  | 
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| 245 | * @param string default: '_inc/blocks/'  | 
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| 246 | */  | 
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| 247 | return apply_filters( 'jetpack_blocks_directory', '_inc/blocks/' );  | 
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| 248 | }  | 
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| 249 | |||
| 250 | /**  | 
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| 251 | * Checks for a given .json file in the blocks folder.  | 
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| 252 | *  | 
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| 253 | * @param string $preset The name of the .json file to look for.  | 
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| 254 | *  | 
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| 255 | * @return bool True if the file is found.  | 
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| 256 | */  | 
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| 257 | 	public static function preset_exists( $preset ) { | 
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| 258 | return file_exists( JETPACK__PLUGIN_DIR . self::get_blocks_directory() . $preset . '.json' );  | 
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| 259 | }  | 
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| 260 | |||
| 261 | /**  | 
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| 262 | * Decodes JSON loaded from a preset file in the blocks folder  | 
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| 263 | *  | 
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| 264 | * @param string $preset The name of the .json file to load.  | 
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| 265 | *  | 
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| 266 | * @return mixed Returns an object if the file is present, or false if a valid .json file is not present.  | 
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| 267 | */  | 
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| 268 | 	public static function get_preset( $preset ) { | 
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| 269 | return json_decode( file_get_contents( JETPACK__PLUGIN_DIR . self::get_blocks_directory() . $preset . '.json' ) );  | 
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| 270 | }  | 
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| 271 | |||
| 272 | /**  | 
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| 273 | * Returns a whitelist of Jetpack Gutenberg extensions (blocks and plugins), based on index.json  | 
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| 274 | *  | 
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| 275 | * @return array A list of blocks: eg [ 'publicize', 'markdown' ]  | 
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| 276 | */  | 
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| 277 | 	public static function get_jetpack_gutenberg_extensions_whitelist() { | 
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| 278 | $preset_extensions_manifest = self::preset_exists( 'index' ) ? self::get_preset( 'index' ) : (object) array();  | 
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| 279 | |||
| 280 | $preset_extensions = isset( $preset_extensions_manifest->production ) ? (array) $preset_extensions_manifest->production : array();  | 
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| 281 | |||
| 282 | 		if ( Jetpack_Constants::is_true( 'JETPACK_BETA_BLOCKS' ) ) { | 
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| 283 | $beta_extensions = isset( $preset_extensions_manifest->beta ) ? (array) $preset_extensions_manifest->beta : array();  | 
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| 284 | return array_unique( array_merge( $preset_extensions, $beta_extensions ) );  | 
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| 285 | }  | 
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| 286 | |||
| 287 | return $preset_extensions;  | 
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| 288 | }  | 
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| 289 | |||
| 290 | /**  | 
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| 291 | * Get availability of each block / plugin.  | 
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| 292 | *  | 
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| 293 | * @return array A list of block and plugins and their availablity status  | 
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| 294 | */  | 
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| 295 | 	public static function get_availability() { | 
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| 296 | |||
| 297 | /**  | 
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| 298 | * Fires before Gutenberg extensions availability is computed.  | 
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| 299 | *  | 
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| 300 | * In the function call you supply, use `jetpack_register_block()` and `jetpack_register_plugin()`, respectively.  | 
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| 301 | * Alternatively, use `jetpack_set_extension_unavailability_reason()` if the block or plugin should not be registered but  | 
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| 302 | * marked as unavailable.  | 
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| 303 | *  | 
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| 304 | * @since 7.0.0  | 
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| 305 | */  | 
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| 306 | do_action( 'jetpack_register_gutenberg_extensions' );  | 
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| 307 | |||
| 308 | $available_extensions = array();  | 
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| 309 | |||
| 310 | 		foreach ( self::$extensions as $extension ) { | 
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| 311 | $is_available = WP_Block_Type_Registry::get_instance()->is_registered( 'jetpack/' . $extension ) ||  | 
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| 312 | in_array( 'jetpack-' . $extension, self::$registered_plugins, true );  | 
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| 313 | |||
| 314 | $available_extensions[ $extension ] = array(  | 
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| 315 | 'available' => $is_available,  | 
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| 316 | );  | 
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| 317 | |||
| 318 | 			if ( ! $is_available ) { | 
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| 319 | $reason = isset( self::$availability[ $extension ] ) ? self::$availability[ $extension ] : 'missing_module';  | 
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| 320 | $available_extensions[ $extension ]['unavailable_reason'] = $reason;  | 
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| 321 | }  | 
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| 322 | }  | 
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| 323 | |||
| 324 | $unwhitelisted = array_fill_keys(  | 
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| 325 | array_diff( array_keys( self::$availability ), self::$extensions ),  | 
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| 326 | array(  | 
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| 327 | 'available' => false,  | 
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| 328 | 'unavailable_reason' => 'not_whitelisted',  | 
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| 329 | )  | 
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| 330 | );  | 
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| 331 | |||
| 332 | return array_merge( $available_extensions, $unwhitelisted );  | 
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| 333 | }  | 
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| 334 | |||
| 335 | /**  | 
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| 336 | * Check if Gutenberg editor is available  | 
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| 337 | *  | 
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| 338 | * @since 6.7.0  | 
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| 339 | *  | 
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| 340 | * @return bool  | 
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| 341 | */  | 
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| 342 | 	public static function is_gutenberg_available() { | 
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| 343 | return function_exists( 'register_block_type' );  | 
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| 344 | }  | 
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| 345 | |||
| 346 | /**  | 
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| 347 | * Check whether conditions indicate Gutenberg Extensions (blocks and plugins) should be loaded  | 
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| 348 | *  | 
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| 349 | * Loading blocks and plugins is enabled by default and may be disabled via filter:  | 
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| 350 | * add_filter( 'jetpack_gutenberg', '__return_false' );  | 
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| 351 | *  | 
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| 352 | * @since 6.9.0  | 
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| 353 | *  | 
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| 354 | * @return bool  | 
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| 355 | */  | 
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| 356 | 	public static function should_load() { | 
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| 370 | |||
| 371 | /**  | 
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| 372 | * Only enqueue block assets when needed.  | 
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| 373 | *  | 
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| 374 | * @param string $type slug of the block.  | 
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| 375 | * @param array $script_dependencies An array of view-side Javascript dependencies to be enqueued.  | 
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| 376 | *  | 
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| 377 | * @return void  | 
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| 378 | */  | 
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| 379 | 	public static function load_assets_as_required( $type, $script_dependencies = array() ) { | 
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| 408 | |||
| 409 | /**  | 
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| 410 | * Check if an asset exists for a block.  | 
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| 411 | *  | 
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| 412 | * @param string $file Path of the file we are looking for.  | 
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| 413 | *  | 
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| 414 | * @return bool $block_has_asset Does the file exist.  | 
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| 415 | */  | 
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| 416 | 	public static function block_has_asset( $file ) { | 
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| 419 | |||
| 420 | /**  | 
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| 421 | * Get the version number to use when loading the file. Allows us to bypass cache when developing.  | 
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| 422 | *  | 
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| 423 | * @param string $file Path of the file we are looking for.  | 
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| 424 | *  | 
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| 425 | * @return string $script_version Version number.  | 
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| 426 | */  | 
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| 427 | 	public static function get_asset_version( $file ) { | 
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| 432 | |||
| 433 | /**  | 
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| 434 | * Load Gutenberg editor assets  | 
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| 435 | *  | 
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| 436 | * @since 6.7.0  | 
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| 437 | *  | 
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| 438 | * @return void  | 
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| 439 | */  | 
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| 440 | 	public static function enqueue_block_editor_assets() { | 
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| 441 | 		if ( ! self::should_load() ) { | 
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| 442 | return;  | 
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| 443 | }  | 
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| 444 | |||
| 445 | $rtl = is_rtl() ? '.rtl' : '';  | 
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| 446 | $beta = Jetpack_Constants::is_true( 'JETPACK_BETA_BLOCKS' ) ? '-beta' : '';  | 
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| 502 | }  | 
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| 503 |