feat(epub): complete wxread parity scope

Sources/RDReaderView/EPUBCore/RDEPUBPreferences.swift

@@ -25,12 +25,18 @@ public struct RDEPUBPreferences: Equatable {
     public var fixedLayoutFit: RDEPUBFixedLayoutFit
     /// 固定版式双页展开模式（never/always/automatic）
     public var fixedLayoutSpreadMode: RDEPUBFixedLayoutSpreadMode
+    /// 多栏排版栏数
+    public var numberOfColumns: Int
+    /// 多栏排版栏间距
+    public var columnGap: CGFloat
 
     public init(
         fontSize: CGFloat,
         lineHeightMultiple: CGFloat,
         reflowableContentInsets: UIEdgeInsets,
         fixedContentInset: UIEdgeInsets,
+        numberOfColumns: Int = 1,
+        columnGap: CGFloat = 20,
         themeBackgroundColor: String? = nil,
         themeTextColor: String? = nil,
         fixedBackgroundColor: String? = nil,
@@ -41,6 +47,8 @@ public struct RDEPUBPreferences: Equatable {
         self.lineHeightMultiple = lineHeightMultiple
         self.reflowableContentInsets = reflowableContentInsets
         self.fixedContentInset = fixedContentInset
+        self.numberOfColumns = max(1, numberOfColumns)
+        self.columnGap = max(0, columnGap)
         self.themeBackgroundColor = themeBackgroundColor
         self.themeTextColor = themeTextColor
         self.fixedBackgroundColor = fixedBackgroundColor
@@ -55,6 +63,8 @@ public struct RDEPUBPreferences: Equatable {
             contentInsets: reflowableContentInsets,
             fontSize: fontSize,
             lineHeightMultiple: lineHeightMultiple,
+            numberOfColumns: numberOfColumns,
+            columnGap: columnGap,
             themeBackgroundColor: themeBackgroundColor,
             themeTextColor: themeTextColor
         )
@@ -99,4 +109,4 @@ public struct RDEPUBPreferences: Equatable {
             )
         )
     }
-}
+}