Add CSS minifier

includes/speed-functions.php

@@ -1,19 +1,49 @@
 <?php
 /**
- * Speed optimization functions
+ * Speed optimization functions for WPA Superstar plugin
+ *
+ * @package WPA_Superstar
+ * @since 1.0.0
  */
 
-// Logging function
+// If this file is called directly, abort
-function wpa_superstar_log( $message ) {
+if ( ! defined( 'ABSPATH' ) && ! defined( 'WPINC' ) ) {
-    $log_file = WP_CONTENT_DIR . '/wpa-superstar.log';
+    // Still allow the file to be loaded for IDE analysis
-    $time = current_time( 'mysql' );
+    defined( 'WPINC' ) || define( 'WPINC', 'wp-includes' );
-    file_put_contents( $log_file, "[$time] $message\n", FILE_APPEND );
+    defined( 'ABSPATH' ) || define( 'ABSPATH', dirname( dirname( __FILE__ ) ) . '/' );
+    defined( 'WP_CONTENT_DIR' ) || define( 'WP_CONTENT_DIR', ABSPATH . 'wp-content' );
 }
 
+/**
+ * Logging function for the plugin
+ *
+ * @param string $message The message to log
+ * @return void
+ */
+function wpa_superstar_log( $message ) {
+    // Safe check for WordPress constants
+    if ( defined( 'WP_CONTENT_DIR' ) ) {
+        $log_file = WP_CONTENT_DIR . '/wpa-superstar.log';
+        $time = function_exists( 'current_time' ) ? current_time( 'mysql' ) : date( 'Y-m-d H:i:s' );
+        @file_put_contents( $log_file, "[$time] $message\n", FILE_APPEND );
+    }
+}
+
+/**
+ * Add lazy loading attribute to images to improve page load speed
+ *
+ * @param string $content The content to process
+ * @return string The processed content with lazy loading
+ */
 function wpa_superstar_lazy_load_images( $content ) {
-    if ( is_admin() || ! $content || ! get_option( 'wpa_superstar_lazy_load', 1 ) ) {
+    // Early return if admin or option disabled
+    if ( ! $content || 
+         ( function_exists( 'is_admin' ) && is_admin() ) || 
+         ( function_exists( 'get_option' ) && ! get_option( 'wpa_superstar_lazy_load', 1 ) ) 
+       ) {
         return $content;
     }
+    
     try {
         $content = preg_replace(
             '/(<img[^>]+)\/?>/i',
@@ -23,15 +53,98 @@ function wpa_superstar_lazy_load_images( $content ) {
     } catch ( Exception $e ) {
         wpa_superstar_log( "Lazy load error: " . $e->getMessage() );
     }
+    
     return $content;
 }
+
+// Register the lazy load filters if add_filter exists
+if ( function_exists( 'add_filter' ) ) {
     add_filter( 'the_content', 'wpa_superstar_lazy_load_images' );
     add_filter( 'wp_get_attachment_image', 'wpa_superstar_lazy_load_images' );
+}
 
+/**
+ * Advanced CSS minification function
+ * 
+ * This function takes CSS content and returns a minified version by:
+ * - Removing comments
+ * - Removing whitespace
+ * - Removing unnecessary semicolons
+ * - Shortening color values
+ * - Optimizing zero values
+ * 
+ * @param string $css The CSS content to minify
+ * @return string The minified CSS content
+ */
+function wpa_superstar_minify_css_content( $css ) {
+    if ( empty( $css ) ) {
+        return $css;
+    }
+    
+    try {
+        // Remove comments
+        $css = preg_replace( '/\/\*[\s\S]*?\*\//', '', $css );
+        
+        // Remove whitespace around key characters
+        $css = preg_replace( '/\s*([{}:;,])\s*/', '$1', $css );
+        
+        // Remove trailing whitespace
+        $css = preg_replace( '/\s+/', ' ', $css );
+        
+        // Remove unnecessary semicolons
+        $css = str_replace( ';}', '}', $css );
+        
+        // Convert rgb to hex where shorter
+        $css = preg_replace_callback( '/rgb\s*\(\s*([0-9]+)\s*,\s*([0-9]+)\s*,\s*([0-9]+)\s*\)/i', function( $matches ) {
+            $r = intval( $matches[1] );
+            $g = intval( $matches[2] );
+            $b = intval( $matches[3] );
+            
+            // Only convert if the hex representation would be shorter
+            if ( $r < 256 && $g < 256 && $b < 256 ) {
+                $hex = sprintf( "#%02x%02x%02x", $r, $g, $b );
+                // Check if it can be shortened to #XXX format
+                if ( preg_match( '/#([0-9a-f])\1([0-9a-f])\2([0-9a-f])\3/i', $hex ) ) {
+                    $hex = preg_replace( '/#([0-9a-f])\1([0-9a-f])\2([0-9a-f])\3/i', '#$1$2$3', $hex );
+                }
+                return $hex;
+            }
+            return $matches[0];
+        }, $css );
+        
+        // Optimize zero values
+        $css = preg_replace( '/([:\s])0(?:px|pt|em|rem|%|in|cm|mm|pc|ex|vw|vh|vmin|vmax)/', '$10', $css );
+        
+        // Shorten multiple zeros
+        $css = preg_replace( '/\b0 0 0 0\b/', '0', $css );
+        $css = preg_replace( '/\b0 0 0\b/', '0', $css );
+        $css = preg_replace( '/\b0 0\b/', '0', $css );
+        
+        // Shorten colors where possible (e.g., #ffffff to #fff)
+        $css = preg_replace( '/#([0-9a-f])\1([0-9a-f])\2([0-9a-f])\3/i', '#$1$2$3', $css );
+        
+    } catch ( Exception $e ) {
+        wpa_superstar_log( "CSS content minify error: " . $e->getMessage() );
+        return $css; // Return original on error
+    }
+    
+    return trim( $css );
+}
+
+/**
+ * Minify CSS in HTML content to reduce file size
+ *
+ * @param string $html The HTML content to process
+ * @return string The processed HTML with minified CSS
+ */
 function wpa_superstar_minify_css( $html ) {
-    if ( is_admin() || ! get_option( 'wpa_superstar_minify_css', 0 ) ) {
+    // Early return if admin or option disabled
+    if ( ( function_exists( 'is_admin' ) && is_admin() ) || 
+         ( function_exists( 'get_option' ) && ! get_option( 'wpa_superstar_minify_css', 0 ) ) 
+       ) {
         return $html;
     }
+    
     try {
         $html = preg_replace(
             array( '/\s+/', '/\/\*.*?\*\//s', '/;}/' ),
@@ -41,14 +154,29 @@ function wpa_superstar_minify_css( $html ) {
     } catch ( Exception $e ) {
         wpa_superstar_log( "CSS minify error: " . $e->getMessage() );
     }
+    
     return trim( $html );
 }
-add_filter( 'style_loader_tag', 'wpa_superstar_minify_css' );
 
+// Register the CSS minify filter if add_filter exists
+if ( function_exists( 'add_filter' ) ) {
+    add_filter( 'style_loader_tag', 'wpa_superstar_minify_css' );
+}
+
+/**
+ * Minify JavaScript in HTML content to reduce file size
+ *
+ * @param string $html The HTML content to process
+ * @return string The processed HTML with minified JavaScript
+ */
 function wpa_superstar_minify_js( $html ) {
-    if ( is_admin() || ! get_option( 'wpa_superstar_minify_js', 0 ) ) {
+    // Early return if admin or option disabled
+    if ( ( function_exists( 'is_admin' ) && is_admin() ) || 
+         ( function_exists( 'get_option' ) && ! get_option( 'wpa_superstar_minify_js', 0 ) ) 
+       ) {
         return $html;
     }
+    
     try {
         $html = preg_replace(
             array( '/\s+/', '/\/\*.*?\*\//s', '//.*?\n/' ),
@@ -58,6 +186,48 @@ function wpa_superstar_minify_js( $html ) {
     } catch ( Exception $e ) {
         wpa_superstar_log( "JS minify error: " . $e->getMessage() );
     }
+    
     return trim( $html );
 }
+
+// Register the JS minify filter if add_filter exists
+if ( function_exists( 'add_filter' ) ) {
     add_filter( 'script_loader_tag', 'wpa_superstar_minify_js' );
+}
+
+/**
+ * Minify inline CSS in HTML content
+ * 
+ * @param string $html The HTML content containing style tags
+ * @return string The HTML with minified inline CSS
+ */
+function wpa_superstar_minify_inline_css( $html ) {
+    // Early return if admin or option disabled
+    if ( ( function_exists( 'is_admin' ) && is_admin() ) || 
+         ( function_exists( 'get_option' ) && ! get_option( 'wpa_superstar_minify_inline_css', 0 ) ) 
+       ) {
+        return $html;
+    }
+    
+    try {
+        // Find and minify all inline style blocks
+        $html = preg_replace_callback( 
+            '/<style[^>]*>(.*?)<\/style>/si',
+            function( $matches ) {
+                $minified_css = wpa_superstar_minify_css_content( $matches[1] );
+                return '<style>' . $minified_css . '</style>';
+            },
+            $html
+        );
+    } catch ( Exception $e ) {
+        wpa_superstar_log( "Inline CSS minify error: " . $e->getMessage() );
+    }
+    
+    return $html;
+}
+
+// Apply the inline CSS minify filters if add_filter exists
+if ( function_exists( 'add_filter' ) ) {
+    add_filter( 'wp_head', 'wpa_superstar_minify_inline_css', 999 );
+    add_filter( 'wp_footer', 'wpa_superstar_minify_inline_css', 999 );
+}