Fix copy/paste text colors from others attributed sources.

Author: SergioEstevao

Aztec/Classes/TextKit/TextViewPasteboardDelegate.swift

@@ -58,7 +58,7 @@ open class AztecTextViewPasteboardDelegate: TextViewPasteboardDelegate {
         guard let string = UIPasteboard.general.attributedString() else {
             return false
         }
-
+        string.loadLazyAttachments()
         let selectedRange = textView.selectedRange
         let storage = textView.storage
 
@@ -69,9 +69,9 @@ open class AztecTextViewPasteboardDelegate: TextViewPasteboardDelegate {
             textView?.undoTextReplacement(of: originalText, finalRange: finalRange)
         })
 
-        string.loadLazyAttachments()
+        let colorCorrectedString = fixColors(in: string, using: textView.textColor)
 
-        storage.replaceCharacters(in: selectedRange, with: string)
+        storage.replaceCharacters(in: selectedRange, with: colorCorrectedString)
         textView.notifyTextViewDidChange()
 
         let newSelectedRange = NSRange(location: selectedRange.location + string.length, length: 0)
@@ -80,6 +80,21 @@ open class AztecTextViewPasteboardDelegate: TextViewPasteboardDelegate {
         return true
     }
 
+    private func fixColors(in string: NSAttributedString, using baseColor: UIColor?) -> NSAttributedString {
+        guard #available(iOS 13.0, *) else {
+            return string
+        }
+        let colorToUse = baseColor ?? UIColor.label
+
+        let newString = NSMutableAttributedString(attributedString: string)
+        newString.enumerateAttributes(in: newString.rangeOfEntireString, options: []) { (attributes, range, stop) in
+            if attributes[.foregroundColor] == nil {
+                newString.setAttributes([.foregroundColor: colorToUse], range: range)
+            }
+        }
+        return newString
+    }
+
     /// Tries to paste raw text from the clipboard, replacing the selected range.
     ///
     /// - Returns: True if the paste succeeds, false if it does not.