1 files changed, 65 insertions, 0 deletions
diff --git a/lib/entry/libimagentryfilter/src/builtin/header/field_predicate.rs b/lib/entry/libimagentryfilter/src/builtin/header/field_predicate.rs
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index 00000000..45aa332c
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+++ b/lib/entry/libimagentryfilter/src/builtin/header/field_predicate.rs
@@ -0,0 +1,65 @@
+//
+// imag - the personal information management suite for the commandline
+// Copyright (C) 2015, 2016 Matthias Beyer <mail@beyermatthias.de> and contributors
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; version
+// 2.1 of the License.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+//
+
+use libimagstore::store::Entry;
+use libimagstore::toml_ext::TomlValueExt;
+
+use builtin::header::field_path::FieldPath;
+use filters::filter::Filter;
+
+use toml::Value;
+
+pub trait Predicate {
+    fn evaluate(&self, Value) -> bool;
+}
+
+/// Check whether certain header field in a entry is equal to a value
+pub struct FieldPredicate<P: Predicate> {
+    header_field_path: FieldPath,
+    predicate: Box<P>,
+}
+
+impl<P: Predicate> FieldPredicate<P> {
+
+    pub fn new(path: FieldPath, predicate: Box<P>) -> FieldPredicate<P> {
+        FieldPredicate {
+            header_field_path: path,
+            predicate: predicate,
+        }
+    }
+
+}
+
+impl<P: Predicate> Filter<Entry> for FieldPredicate<P> {
+
+    fn filter(&self, e: &Entry) -> bool {
+        e.get_header()
+            .read(&self.header_field_path[..])
+            .map(|val| {
+                match val {
+                    None => false,
+                    Some(v) => (*self.predicate).evaluate(v),
+                }
+            })
+            .unwrap_or(false)
+    }
+
+}
+
+