Format TUI commit activity previews

crates/gitea/src/activity.rs

@@ -70,6 +70,20 @@ pub enum Target {
     },
 }
 
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct CommitActivity {
+    pub count: usize,
+    pub commits: Vec<ActivityCommit>,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct ActivityCommit {
+    pub sha: String,
+    pub message: String,
+    pub author: String,
+    pub timestamp: String,
+}
+
 impl Client {
     pub async fn activities(
         &self,
@@ -205,6 +219,28 @@ pub fn target(activity: &models::Activity) -> Option<Target> {
     }
 }
 
+pub fn commit_activity(activity: &models::Activity) -> Option<CommitActivity> {
+    let payload: serde_json::Value = serde_json::from_str(activity.content.as_deref()?).ok()?;
+    let mut commits = field(&payload, "Commits")
+        .and_then(serde_json::Value::as_array)
+        .into_iter()
+        .flatten()
+        .filter_map(activity_commit)
+        .collect::<Vec<_>>();
+    if commits.is_empty()
+        && let Some(commit) = field(&payload, "HeadCommit").and_then(activity_commit)
+    {
+        commits.push(commit);
+    }
+    (!commits.is_empty()).then(|| CommitActivity {
+        count: field(&payload, "Len")
+            .and_then(serde_json::Value::as_u64)
+            .and_then(|count| usize::try_from(count).ok())
+            .unwrap_or(commits.len()),
+        commits,
+    })
+}
+
 fn issue_number(activity: &models::Activity) -> Option<i64> {
     activity
         .comment
@@ -233,13 +269,14 @@ fn url_number(url: &str) -> Option<i64> {
 
 fn commit_sha(content: &str) -> Option<String> {
     let payload: serde_json::Value = serde_json::from_str(content).ok()?;
-    payload.get("HeadCommit").and_then(find_sha).or_else(|| {
-        payload
-            .get("Commits")?
-            .as_array()?
-            .last()
-            .and_then(find_sha)
-    })
+    field(&payload, "HeadCommit")
+        .and_then(find_sha)
+        .or_else(|| {
+            field(&payload, "Commits")?
+                .as_array()?
+                .last()
+                .and_then(find_sha)
+        })
 }
 
 fn find_sha(value: &serde_json::Value) -> Option<String> {
@@ -252,6 +289,35 @@ fn find_sha(value: &serde_json::Value) -> Option<String> {
     })
 }
 
+fn activity_commit(value: &serde_json::Value) -> Option<ActivityCommit> {
+    let sha = find_sha(value).unwrap_or_default();
+    let message = string_field(value, "Message")
+        .unwrap_or_default()
+        .to_string();
+    (!sha.is_empty() || !message.is_empty()).then(|| ActivityCommit {
+        sha,
+        message,
+        author: string_field(value, "AuthorName")
+            .or_else(|| string_field(value, "CommitterName"))
+            .unwrap_or_default()
+            .to_string(),
+        timestamp: string_field(value, "Timestamp")
+            .unwrap_or_default()
+            .to_string(),
+    })
+}
+
+fn string_field<'a>(value: &'a serde_json::Value, name: &str) -> Option<&'a str> {
+    field(value, name).and_then(serde_json::Value::as_str)
+}
+
+fn field<'a>(value: &'a serde_json::Value, name: &str) -> Option<&'a serde_json::Value> {
+    value
+        .as_object()?
+        .iter()
+        .find_map(|(key, value)| key.eq_ignore_ascii_case(name).then_some(value))
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -299,6 +365,36 @@ mod tests {
         );
     }
 
+    #[test]
+    fn decodes_forgejo_commit_activity_for_presentation() {
+        let activity = activity(
+            OpType::CommitRepo,
+            r#"{
+                "Commits": [{
+                    "Sha1": "0123456789abcdef",
+                    "Message": "Fix the preview\n\nDetails",
+                    "AuthorName": "Octo Cat",
+                    "Timestamp": "2026-08-04T19:04:30+02:00"
+                }],
+                "HeadCommit": {"Sha1": "0123456789abcdef"},
+                "Len": 1
+            }"#,
+        );
+
+        assert_eq!(
+            commit_activity(&activity),
+            Some(CommitActivity {
+                count: 1,
+                commits: vec![ActivityCommit {
+                    sha: "0123456789abcdef".into(),
+                    message: "Fix the preview\n\nDetails".into(),
+                    author: "Octo Cat".into(),
+                    timestamp: "2026-08-04T19:04:30+02:00".into(),
+                }],
+            })
+        );
+    }
+
     #[test]
     fn filters_issue_and_pull_request_activity() {
         let activities = [