Add associated file typed array writers (#41)

src/annotations.rs

@@ -228,6 +228,12 @@ impl<'a> Annotation<'a> {
         self.pair(Name(b"Parent"), id);
         self
     }
+
+    /// Start writing the `/AF` array to specify the associated files of the
+    /// annotation. PDF 2.0+ or PDF/A-3.
+    pub fn associated_files(&mut self) -> TypedArray<'_, FileSpec> {
+        self.insert(Name(b"AF")).array().typed()
+    }
 }
 
 deref!('a, Annotation<'a> => Dict<'a>, dict);

src/files.rs

@@ -53,8 +53,9 @@ impl<'a> FileSpec<'a> {
     /// PDF 1.3+.
     ///
     /// This only sets an embedded file for the `F` attribute corresponding to
-    /// the [`path`](Self::path) method. You will need to write this dictionary
-    /// manually if you need to set `UF` which is required in PDF/A-3.
+    /// the [`path`](Self::path) method. If you want to set the same embedded
+    /// file for the `UF` attribute, also call [`Self::embedded_file_with_unicode`]
+    /// instead.
     ///
     /// Note that this key is forbidden in PDF/A-1 and restricted in PDF/A-2 and
     /// PDF/A-4.
@@ -63,6 +64,19 @@ impl<'a> FileSpec<'a> {
         self
     }
 
+    /// Write the `/EF` attribute to reference an [embedded file](EmbeddedFile)
+    /// for the legacy and Unicode-compatible file path. PDF 1.7+.
+    ///
+    /// Note that this key is forbidden in PDF/A-1 and restricted in PDF/A-2 an
+    /// PDF/A-4.
+    pub fn embedded_file_with_unicode(&mut self, id: Ref) -> &mut Self {
+        self.insert(Name(b"EF"))
+            .dict()
+            .pair(Name(b"F"), id)
+            .pair(Name(b"UF"), id);
+        self
+    }
+
     /// How this file relates to the PDF document it is embedded in.
     /// PDF/A-3 and PDF/A-4f.
     pub fn association_kind(&mut self, kind: AssociationKind) -> &mut Self {

src/structure.rs

@@ -147,7 +147,7 @@ impl<'a> Catalog<'a> {
     }
 
     /// Start writing the `/AF` array to specify the associated files of the
-    /// document. PDF 2.0+.
+    /// document. PDF 2.0+ or PDF/A-3.
     pub fn associated_files(&mut self) -> TypedArray<'_, FileSpec> {
         self.insert(Name(b"AF")).array().typed()
     }
@@ -495,6 +495,12 @@ impl<'a> StructElement<'a> {
         self.dict.pair(Name(b"ActualText"), actual_text);
         self
     }
+
+    /// Start writing the `/AF` array to specify the associated files of the
+    /// element. PDF 2.0+ or PDF/A-3.
+    pub fn associated_files(&mut self) -> TypedArray<'_, FileSpec> {
+        self.insert(Name(b"AF")).array().typed()
+    }
 }
 
 deref!('a, StructElement<'a> => Dict<'a>, dict);
@@ -1247,6 +1253,12 @@ impl<'a> Page<'a> {
         self.pair(Name(b"Metadata"), id);
         self
     }
+
+    /// Start writing the `/AF` array to specify the associated files of the
+    /// page. PDF 2.0+ or PDF/A-3.
+    pub fn associated_files(&mut self) -> TypedArray<'_, FileSpec> {
+        self.insert(Name(b"AF")).array().typed()
+    }
 }
 
 deref!('a, Page<'a> => Dict<'a>, dict);

src/xobject.rs

@@ -155,6 +155,12 @@ impl<'a> ImageXObject<'a> {
         self.pair(Name(b"Metadata"), id);
         self
     }
+
+    /// Start writing the `/AF` array to specify the associated files of the
+    /// image. PDF 2.0+ or PDF/A-3.
+    pub fn associated_files(&mut self) -> TypedArray<'_, FileSpec> {
+        self.insert(Name(b"AF")).array().typed()
+    }
 }
 
 deref!('a, ImageXObject<'a> => Stream<'a>, stream);
@@ -263,6 +269,12 @@ impl<'a> FormXObject<'a> {
         self.pair(Name(b"LastModified"), last_modified);
         self
     }
+
+    /// Start writing the `/AF` array to specify the associated files of the
+    /// Form XObject. PDF 2.0+ or PDF/A-3.
+    pub fn associated_files(&mut self) -> TypedArray<'_, FileSpec> {
+        self.insert(Name(b"AF")).array().typed()
+    }
 }
 
 deref!('a, FormXObject<'a> => Stream<'a>, stream);