add is_default script function

doc/function/index.txt

@@ -78,6 +78,7 @@ These functions are built into the program, other [[type:function]]s can be defi
 | [[fun:exclusive_choice]]		Require that at most one of the given choices is selected.
 | [[fun:require_exclusive_choice]]	Require that exactly one of the given choices is selected.
 | [[fun:remove_choice]]			Remove the given choices from a multiple choice value.
+| [[fun:is_default]]			Check if a field is in its default state.
 	
 ! Images			<<<
 | [[fun:linear_blend]]		Blend two images together using a linear gradient.

doc/function/is_default.txt

@@ -0,0 +1,10 @@
+Function: is_default
+
+--Usage--
+> is_default(some_field)
+
+Returns true if the field is in its default state, that is, if the user hasn't modified the value yet, false otherwise.
+
+--Parameters--
+! Parameter	Type			Description
+| @input@	[[type:field]]		Field to test.

src/data/field.cpp

@@ -305,6 +305,10 @@ bool Value::equals(const Value* that) {
   return this == that;
 }
 
+bool Value::isDefault() {
+  return false;
+}
+
 bool Value::update(Context& ctx) {
   updateAge();
   updateSortValue(ctx);

src/data/field.hpp

@@ -256,6 +256,8 @@ public:
 
   /// Convert this value to a string for use in tables
   virtual String toString() const = 0;
+  /// Check if this value is in the default state
+  virtual bool isDefault();
   /// Apply scripts to this value, return true if the value has changed
   virtual bool update(Context& ctx);
   /// This value has been updated by an action

src/data/field/choice.cpp

@@ -318,6 +318,11 @@ ChoiceValue::ChoiceValue(const ChoiceFieldP& field, bool initial_first_choice)
 String ChoiceValue::toString() const {
   return value();
 }
+
+bool ChoiceValue::isDefault() {
+  return value.isDefault();
+}
+
 bool ChoiceValue::update(Context& ctx) {
   bool change = field().default_script.invokeOnDefault(ctx, value)
               | field().        script.invokeOn(ctx, value);

src/data/field/choice.hpp

@@ -200,6 +200,8 @@ public:
   
   ValueType value;  /// The name of the selected choice
 
+  bool isDefault() override;
+
   bool update(Context&) override;
 };
 

src/data/field/color.cpp

@@ -111,6 +111,11 @@ String ColorValue::toString() const {
   }
   return _("<color>");
 }
+
+bool ColorValue::isDefault() {
+  return value.isDefault();
+}
+
 bool ColorValue::update(Context& ctx) {
   bool change = field().default_script.invokeOnDefault(ctx, value)
               | field().        script.invokeOn(ctx, value);

src/data/field/color.hpp

@@ -78,6 +78,8 @@ public:
   
   ValueType value;  ///< The value
 
+  bool isDefault() override;
+
   bool update(Context&) override;
 };
 

src/data/field/image.cpp

@@ -39,6 +39,10 @@ String ImageValue::toString() const {
   return filename.empty() ? _("") : _("<image>");
 }
 
+bool ImageValue::isDefault() {
+  return filename.empty();
+}
+
 // custom reflection: convert to ScriptImageP for scripting
 
 void ImageValue::reflect(Reader& handler) {

src/data/field/image.hpp

@@ -48,6 +48,8 @@ public:
 
   ValueType filename;    ///< Filename of the image (in the current package), or ""
   Age       last_update; ///< When was the image last changed?
+
+  bool isDefault() override;
 };
 
 // ----------------------------------------------------------------------------- : ImageStyle

src/data/field/information.cpp

@@ -63,6 +63,11 @@ IMPLEMENT_REFLECTION(InfoStyle) {
 String InfoValue::toString() const {
   return value;
 }
+
+bool InfoValue::isDefault() {
+  return true;
+}
+
 bool InfoValue::update(Context& ctx) {
   if (value.empty()) value = field().caption.get();
   bool change = field().script.invokeOn(ctx, value);

src/data/field/information.hpp

@@ -61,6 +61,8 @@ public:
   
   ValueType value;
 
+  bool isDefault() override;
+
   bool update(Context&) override;
 };
 

src/data/field/multiple_choice.cpp

@@ -52,6 +52,10 @@ IMPLEMENT_REFLECTION_NAMELESS(MultipleChoiceValue) {
   REFLECT_BASE(ChoiceValue);
 }
 
+bool MultipleChoiceValue::isDefault() {
+  return value.isDefault();
+}
+
 bool MultipleChoiceValue::update(Context& ctx) {
   String old_value = value();
   ctx.setVariable(_("last_change"), to_script(last_change));

src/data/field/multiple_choice.hpp

@@ -64,6 +64,8 @@ public:
   /// Splits the value, stores the selected choices in the out parameter
   void get(vector<String>& out) const;
 
+  bool isDefault() override;
+
   bool update(Context&) override;
   
 private:

src/data/field/package_choice.cpp

@@ -62,6 +62,12 @@ PackagedP PackageChoiceValue::getPackage() const {
   else return package_manager.openAny(package_name, true);
 }
 
+bool PackageChoiceValue::isDefault() {
+  PackageChoiceFieldP packageFieldP = boost::dynamic_pointer_cast<PackageChoiceField>(fieldP);
+  if (packageFieldP) return package_name == packageFieldP->initial;
+  return false;
+}
+
 bool PackageChoiceValue::update(Context& ctx) {
   bool change = field().script.invokeOn(ctx, package_name);
   Value::update(ctx);

src/data/field/package_choice.hpp

@@ -62,6 +62,8 @@ public:
   /// Get the package (if it is set), otherwise return nullptr
   PackagedP getPackage() const;
 
+  bool isDefault() override;
+
   bool update(Context&) override;
 };
 

src/data/field/symbol.cpp

@@ -51,6 +51,10 @@ String SymbolValue::toString() const {
   return filename.empty() ? _("") : _("<symbol>");
 }
 
+bool SymbolValue::isDefault() {
+  return filename.empty();
+}
+
 IMPLEMENT_REFLECTION_NO_GET_MEMBER(SymbolValue) {
   if (fieldP->save_value || !handler.isWriting) REFLECT_NAMELESS(filename);
 }

src/data/field/symbol.hpp

@@ -70,5 +70,7 @@ public:
   
   ValueType filename;    ///< Filename of the symbol (in the current package)
   Age       last_update; ///< When was the symbol last changed?
+
+  bool isDefault() override;
 };
 

src/data/field/text.cpp

@@ -177,6 +177,11 @@ IMPLEMENT_REFLECTION(TextStyle) {
 String TextValue::toString() const {
   return untag_hide_sep(value());
 }
+
+bool TextValue::isDefault() {
+  return value.isDefault();
+}
+
 bool TextValue::update(Context& ctx) {
   updateAge();
   WITH_DYNAMIC_ARG(last_update_age,     last_update.get());

src/data/field/text.hpp

@@ -113,6 +113,8 @@ public:
   ValueType value;                ///< The text of this value
   Age       last_update;          ///< When was the text last changed?
 
+  bool isDefault() override;
+
   bool update(Context&) override;
 };
 

src/render/value/image.cpp

@@ -117,13 +117,14 @@ Bitmap ImageValueViewer::imagePlaceholder(const Rotation& rot, UInt w, UInt h, c
   // Draw text
   if (editing) {
     // only when in editor mode
+    String label = _LABEL_("load image");
     for (UInt size = 12 ; size > 2 ; --size) {
       dc.SetFont(wxFont(size, wxFONTFAMILY_SWISS, wxFONTSTYLE_NORMAL, wxFONTWEIGHT_NORMAL));
-      RealSize rs = dc.GetTextExtent(_LABEL_("load image"));
+      RealSize rs = dc.GetTextExtent(label);
       if (rs.width <= w - 10 && rs.height < h - 10) {
         // text fits
         RealPoint pos = align_in_rect(ALIGN_MIDDLE_CENTER, rs, rect);
-        dc.DrawText(_LABEL_("load image"), pos, Color(255,255,255), 2, Color(0,0,0), 3); // stroked
+        dc.DrawText(label, pos, Color(255,255,255), 2, Color(0,0,0), 3); // stroked
         break;
       }
     }

src/script/functions/editor.cpp

@@ -189,6 +189,13 @@ SCRIPT_FUNCTION_DEPENDENCIES(combined_editor) {
   return dependency_dummy;
 }
 
+// ----------------------------------------------------------------------------- : Values
+
+SCRIPT_FUNCTION(is_default) {
+  SCRIPT_PARAM_C(ValueP,input);
+  SCRIPT_RETURN(input->isDefault());
+}
+
 // ----------------------------------------------------------------------------- : Choice values
 
 // convert a full choice name into the name of the top level group it is in
@@ -389,6 +396,7 @@ SCRIPT_FUNCTION(count_chosen) {
 void init_script_editor_functions(Context& ctx) {
   ctx.setVariable(_("forward_editor"),           script_combined_editor); // compatability
   ctx.setVariable(_("combined_editor"),          script_combined_editor);
+  ctx.setVariable(_("is_default"),               script_is_default);
   ctx.setVariable(_("primary_choice"),           script_primary_choice);
   ctx.setVariable(_("chosen"),                   script_chosen);
   ctx.setVariable(_("count_chosen"),             script_count_chosen);