1 files changed, 41 insertions, 0 deletions
diff --git a/src/frontend/json.rs b/src/frontend/json.rs
index 9cf5573..b6a34e5 100644
--- a/src/frontend/json.rs
+++ b/src/frontend/json.rs
@@ -4,10 +4,14 @@ use std::ops::Deref;
 
 use librepology::v1::types::Package;
 use librepology::v1::types::Problem;
+use librepology::v1::types::Repo;
 use failure::Fallible as Result;
 use failure::Error;
 
 use crate::frontend::Frontend;
+use crate::backend::Backend;
+use crate::compare::ComparePackage;
+use librepology::v1::api::Api;
 
 pub struct JsonFrontend(Stdout);
 
@@ -29,5 +33,42 @@ impl Frontend for JsonFrontend {
         let mut outlock = self.0.lock();
         writeln!(outlock, "{}", output).map_err(Error::from)
     }
+
+    fn compare_packages(&self, packages: Vec<ComparePackage>, backend: &Backend, filter_repos: Vec<Repo>) -> Result<()> {
+        #[derive(Serialize)]
+        struct PackageComp {
+            // not optimal, as we have to clone the inner variables from the package
+            // but using references is too complicated right now
+            package_name: String,
+            local_version: String,
+            upstream_repo: String,
+            upstream_version: String,
+        }
+
+        let mut output: Vec<PackageComp> = vec![];
+
+        for package in packages.iter() {
+            let mut list = backend
+                .project(package.name().deref())?
+                .into_iter()
+                .filter(|p| filter_repos.contains(p.repo()))
+                .map(|upstream_package| {
+                    PackageComp {
+                        package_name: package.name().clone(),
+                        local_version: package.version().clone(),
+                        upstream_repo: upstream_package.repo().deref().clone(),
+                        upstream_version: upstream_package.version().deref().clone(),
+                    }
+                })
+                .collect::<Vec<_>>();
+
+            output.append(&mut list);
+        }
+
+        let output = serde_json::ser::to_string_pretty(&output)?;
+
+        let mut outlock = self.0.lock();
+        writeln!(outlock, "{}", output).map_err(Error::from)
+    }
 }