From c6581e11220cfce71aef1c77a9797b9bf8838c31 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Du=C5=A1an=20Poizl?= <nou.spiro@gmail.com>
Date: Sun, 3 Aug 2025 20:40:56 +0200
Subject: [PATCH] Add method to modify XISF Property

---
 libxisf.cpp | 29 ++++++++++++++++++++++++++++-
 libxisf.h   |  6 ++++++
 variant.cpp |  2 --
 3 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/libxisf.cpp b/libxisf.cpp
index 93c23c1..03ce14f 100644
--- a/libxisf.cpp
+++ b/libxisf.cpp
@@ -1034,11 +1034,11 @@ public:
     void save(std::ostream &io);
     void writeImage(const Image &image);
     static void writeFITSKeyword(pugi::xml_node &node, const FITSKeyword &keyword);
+    static void writePropertyElement(pugi::xml_node &node, const Property &property);
 private:
     void writeHeader();
     void writeImageElement(pugi::xml_node &node, const Image &image);
     void writeDataBlockAttributes(pugi::xml_node &image_node, const DataBlock &dataBlock);
-    void writePropertyElement(pugi::xml_node &node, const Property &property);
     void writeMetadata(pugi::xml_node &node);
     void updateImageAttachmentPos(pugi::xml_node &root, size_t offset);
     ByteArray _xisfHeader;
@@ -1371,6 +1371,7 @@ public:
     void addFITSKeyword(uint32_t image, const FITSKeyword &keyword);
     void updateFITSKeyword(uint32_t image, const FITSKeyword &keyword, bool add);
     void removeFITSKeyword(uint32_t image, const String &name);
+    void updateProperty(uint32_t image, const Property &property);
 private:
     void readXISFHeader();
     void parseAttachmentPos(pugi::xml_node &root);
@@ -1551,6 +1552,27 @@ void XISFModifyPrivate::removeFITSKeyword(uint32_t image, const String &name)
         imageNode.remove_child(keywordNode);
 }
 
+void XISFModifyPrivate::updateProperty(uint32_t image, const Property &property)
+{
+    if(!_root)
+        throw Error("No input file opened");
+
+    pugi::xpath_node_set images = _root.select_nodes("//Image");
+
+    if(image >= images.size())
+        throw Error("Out of bounds");
+
+    pugi::xpath_variable_set variables;
+    variables.set("id", property.id.c_str());
+    pugi::xml_node imageNode = images[image].node();
+    pugi::xml_node propertyNode = imageNode.select_node("Property[@id=string($id)]", &variables).node();
+
+    if(propertyNode)
+        imageNode.remove_child(propertyNode);
+
+    XISFWriterPrivate::writePropertyElement(imageNode, property);
+}
+
 void XISFModifyPrivate::readXISFHeader()
 {
     char signature[8];
@@ -1669,6 +1691,11 @@ void XISFModify::removeFITSKeyword(uint32_t image, const String &name)
     p->removeFITSKeyword(image, name);
 }
 
+void XISFModify::updateProperty(uint32_t image, const Property &property)
+{
+    p->updateProperty(image, property);
+}
+
 #define STRING_ENUM(map, map2, c, e) { map.insert({#e, c::e}); map2.insert({c::e, #e}); }
 
 struct Init
diff --git a/libxisf.h b/libxisf.h
index 0442694..2e8981d 100644
--- a/libxisf.h
+++ b/libxisf.h
@@ -443,6 +443,12 @@ public:
      * @param name of keyword that will be removed
      */
     void removeFITSKeyword(uint32_t image, const String &name);
+    /**
+     * @brief updateProperty add new or update existing XISF Property
+     * @param image index of image to update
+     * @param property new value of property
+     */
+    void updateProperty(uint32_t image, const Property &property);
 private:
     XISFModifyPrivate *p;
 };
diff --git a/variant.cpp b/variant.cpp
index bb8ba75..c9366ce 100644
--- a/variant.cpp
+++ b/variant.cpp
@@ -17,7 +17,6 @@
  ************************************************************************/
 
 #include <charconv>
-#include <type_traits>
 #include <map>
 #include <regex>
 #include <iomanip>
@@ -403,7 +402,6 @@ Variant variantFromString(Variant::Type type, const String &str)
 
 Variant::Type Variant::type() const
 {
-    int idx = _value.index();
     return (Variant::Type)_value.index();
 }