Refactor external linking into trait

1 files changed, 43 insertions, 29 deletions

diff --git a/libimaglink/src/external.rs b/libimaglink/src/external.rs
index 1aa0c1ed..faca38ac 100644
--- a/libimaglink/src/external.rs
+++ b/libimaglink/src/external.rs
@@ -7,44 +7,58 @@ use result::Result;
 use toml::Value;
 use toml::Table;
 
-pub fn get_link(header: &EntryHeader) -> Result<Option<Link>> {
-    let uri = header.read("imag.content.uri");
+pub trait ExternalLinker {
 
-    if uri.is_err() {
-        let kind = LinkErrorKind::EntryHeaderReadError;
-        let lerr = LinkError::new(kind, Some(Box::new(uri.err().unwrap())));
-        return Err(lerr);
-    }
-    let uri = uri.unwrap();
+    /// get the external link from the implementor object
+    fn get_external_link(&self) -> Result<Option<Link>>;
 
-    match uri {
-        Some(Value::String(s)) => Ok(Some(Link::new(s))),
-        _ => Err(LinkError::new(LinkErrorKind::ExistingLinkTypeWrong, None)),
-    }
+    /// set the external link for the implementor object and return the current link from the entry,
+    /// if any.
+    fn set_external_link(&mut self, l: Link) -> Result<Option<Link>>;
 }
 
-/// Set an external link in the header
-///
-/// Return the previous set link if there was any
-pub fn set_link(header: &mut EntryHeader, l: Link) -> Result<Option<Link>> {
-    let old_link = header.set("imag.content.uri", Value::String(l.into()));
+impl ExternalLinker for EntryHeader {
 
-    if old_link.is_err() {
-        let kind = LinkErrorKind::EntryHeaderWriteError;
-        let lerr = LinkError::new(kind, Some(Box::new(old_link.err().unwrap())));
-        return Err(lerr);
-    }
-    let old_link = old_link.unwrap();
+    fn get_external_link(&self) -> Result<Option<Link>> {
+        let uri = self.read("imag.content.uri");
+
+        if uri.is_err() {
+            let kind = LinkErrorKind::EntryHeaderReadError;
+            let lerr = LinkError::new(kind, Some(Box::new(uri.err().unwrap())));
+            return Err(lerr);
+        }
+        let uri = uri.unwrap();
 
-    if old_link.is_none() {
-        return Ok(None);
+        match uri {
+            Some(Value::String(s)) => Ok(Some(Link::new(s))),
+            _ => Err(LinkError::new(LinkErrorKind::ExistingLinkTypeWrong, None)),
+        }
     }
 
-    match old_link.unwrap() {
-        Value::String(s) => Ok(Some(Link::new(s))),
+    /// Set an external link in the header
+    ///
+    /// Return the previous set link if there was any
+    fn set_external_link(&mut self, l: Link) -> Result<Option<Link>> {
+        let old_link = self.set("imag.content.uri", Value::String(l.into()));
 
-        // We don't do anything in this case and be glad we corrected the type error with this set()
-        _ => Ok(None),
+        if old_link.is_err() {
+            let kind = LinkErrorKind::EntryHeaderWriteError;
+            let lerr = LinkError::new(kind, Some(Box::new(old_link.err().unwrap())));
+            return Err(lerr);
+        }
+        let old_link = old_link.unwrap();
+
+        if old_link.is_none() {
+            return Ok(None);
+        }
+
+        match old_link.unwrap() {
+            Value::String(s) => Ok(Some(Link::new(s))),
+
+            // We don't do anything in this case and be glad we corrected the type error with this set()
+            _ => Ok(None),
+        }
     }
+
 }