Merge pull request #1103 from matthiasbeyer/libimagentrygps/more-functionality

libimagentrygps: More functionality

lib/entry/libimagentrygps/src/entry.rs

@@ -26,12 +26,32 @@ use libimagstore::store::Entry;
 
 use toml_query::read::TomlValueReadExt;
 use toml_query::insert::TomlValueInsertExt;
+use toml_query::delete::TomlValueDeleteExt;
 
 pub trait GPSEntry {
 
     fn set_coordinates(&mut self, c: Coordinates) -> Result<()>;
     fn get_coordinates(&self) -> Result<Option<Coordinates>>;
 
+    /// Remove the coordinates from the entry
+    ///
+    /// # Returns
+    ///
+    /// The return type is a bit complicated, but that has a reason:
+    ///
+    /// The outer Result<_> is used for notifying a failure during the header read/write action.
+    /// If the Option<_> is Some(_), the value was deleted.
+    /// The inner Result<_> is used for parsing failures during the parsing of the deleted value.
+    ///
+    /// So:
+    ///
+    /// * Ok(Some(Ok(_))) if the coordinates were deleted, returning the deleted value
+    /// * Ok(Some(Err(_))) if the coordinates were deleted, but the deleted value couldn't be parsed
+    /// * Ok(None) if there were no coordinates to delete
+    /// * Err(e) if the deleting failed
+    ///
+    fn remove_coordinates(&mut self) -> Result<Option<Result<Coordinates>>>;
+
 }
 
 impl GPSEntry for Entry {
@@ -51,6 +71,12 @@ impl GPSEntry for Entry {
         }
     }
 
+    fn remove_coordinates(&mut self) -> Result<Option<Result<Coordinates>>> {
+        self.get_header_mut()
+            .delete("gps.coordinates")
+            .chain_err(|| GPSEK::HeaderWriteError)
+            .map(|opt| opt.as_ref().map(Coordinates::from_value))
+    }
 }
 
 #[cfg(test)]

lib/entry/libimagentrygps/src/types.rs

@@ -18,6 +18,9 @@
 //
 
 use std::collections::BTreeMap;
+use std::fmt::Display;
+use std::fmt::Formatter;
+use std::fmt::Result as FmtResult;
 
 use toml::Value;
 
@@ -46,6 +49,19 @@ impl GPSValue {
             seconds: s
         }
     }
+
+    pub fn degree(&self) -> i8 {
+        self.degree
+    }
+
+    pub fn minutes(&self) -> i8 {
+        self.minutes
+    }
+
+    pub fn seconds(&self) -> i8 {
+        self.seconds
+    }
+
 }
 
 
@@ -96,6 +112,12 @@ impl FromValue for GPSValue {
 
 }
 
+impl Display for GPSValue {
+    fn fmt(&self, f: &mut Formatter) -> FmtResult {
+        write!(f, "{}° {}\" {}'", self.degree, self.minutes, self.seconds)
+    }
+}
+
 /// Data-transfer type for transfering longitude-latitude-pairs
 #[derive(Clone, Debug, Serialize, Deserialize, PartialEq, Eq)]
 pub struct Coordinates {
@@ -110,6 +132,14 @@ impl Coordinates {
             latitude:  lat,
         }
     }
+
+    pub fn longitude(&self) -> &GPSValue {
+        &self.longitude
+    }
+
+    pub fn latitude(&self) -> &GPSValue {
+        &self.latitude
+    }
 }
 
 impl Into<Value> for Coordinates {
@@ -145,6 +175,12 @@ impl FromValue for Coordinates {
 
 }
 
+impl Display for Coordinates {
+    fn fmt(&self, f: &mut Formatter) -> FmtResult {
+        write!(f, "longitude = {}\nlatitude = {}", self.longitude, self.latitude)
+    }
+}
+
 /// Helper to convert a i64 to i8 or return an error if this doesn't work.
 fn i64_to_i8(i: i64) -> Result<i8> {
     if i > (<i8>::max_value() as i64) {