Resume interrupted editor co-op runs

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/lobby.rs

@@ -230,10 +230,23 @@ impl MatchClient {
     // a co-op match of an editor campaign: the whole campaign file goes to the relay, which hands
     // it to every client with the start message
     pub fn create_coop_doc(&mut self, doc: &crate::campaign_doc::CampaignDoc, mission: usize, sides: &[u8], difficulty: u8) {
+        self.create_coop_doc_resumed(doc, mission, sides, difficulty, None);
+    }
+
+    // the same, going on with an interrupted run: its seed and what every master carries along
+    pub fn create_coop_doc_resumed(&mut self, doc: &crate::campaign_doc::CampaignDoc, mission: usize, sides: &[u8], difficulty: u8, resume: Option<(u32, &[(u8, crate::campaign::Carry)])>) {
         let Some(m) = doc.missions.get(mission) else { return };
         let (map_w, map_h) = m.size;
         let doc = serde_json::to_value(doc).unwrap_or(Value::Null);
+        let n = self.outbox.len();
         self.send_create_with(sides, map_w, map_h, difficulty, Some(mission), Some(doc));
+        if let (Some((seed, carry)), Some(text)) = (resume, self.outbox.get_mut(n)) {
+            if let Ok(mut msg) = serde_json::from_str::<Value>(text) {
+                msg["seed"] = json!(seed);
+                msg["carry"] = serde_json::to_value(carry).unwrap_or(Value::Array(Vec::new()));
+                *text = msg.to_string();
+            }
+        }
     }
 
     fn send_create(&mut self, sides: &[u8], map_w: usize, map_h: usize, difficulty: u8, mission: Option<usize>) {
@@ -534,7 +547,10 @@ impl MatchClient {
             }
             r.ai = ai.clone();
         }
-        self.start = Some(StartInfo { seed, map_w, map_h, difficulty, sides, local_side, mission, ai, doc, editor, teams, next: false, carry: Vec::new() });
+        // a resumed editor campaign run goes on like the next mission of a running one
+        let resume = editor && v.get("resume").and_then(|x| x.as_bool()).unwrap_or(false);
+        let carry: Vec<(u8, crate::campaign::Carry)> = if resume { v.get("carry").cloned().and_then(|c| serde_json::from_value(c).ok()).unwrap_or_default() } else { Vec::new() };
+        self.start = Some(StartInfo { seed, map_w, map_h, difficulty, sides, local_side, mission, ai, doc, editor, teams, next: resume, carry });
         self.error = None;
         self.status = None;
     }
@@ -898,6 +914,30 @@ mod tests {
         assert_eq!(start.teams, vec![(0, 1), (2, 1)]);
     }
 
+    #[test]
+    fn an_interrupted_coop_run_goes_on_with_its_seed_and_carry() {
+        let doc = coop_doc();
+        let mut host = MatchClient::new();
+        host.on_connect("red");
+        pop(&mut host); // rooms
+        let carry = vec![(0u8, crate::campaign::Carry { gold: 250.0, ..Default::default() })];
+        host.create_coop_doc_resumed(&doc, 1, &[0, 2, 3, 4], 1, Some((4242, &carry)));
+        let create = pop(&mut host);
+        assert_eq!(create["seed"].as_u64(), Some(4242));
+        assert_eq!(create["carry"][0][0].as_u64(), Some(0));
+        assert_eq!(create["mission"].as_u64(), Some(1));
+        let start = json!({"t":"start","seed":4242,"map_w":96,"map_h":96,"difficulty":1,"sides":[0,2],"mission":1,"ai":[],"doc":serde_json::to_value(&doc).unwrap(),"carry":create["carry"].clone(),"resume":true}).to_string();
+        host.feed(&start);
+        let info = host.take_start().unwrap();
+        assert!(info.next, "a resumed run keeps its progress");
+        assert_eq!(info.seed, 4242);
+        assert_eq!(info.carry.len(), 1);
+        assert_eq!(info.carry[0].1.gold, 250.0);
+        // old stored progress without the run position still reads
+        let p: crate::campaign_doc::CampaignProgress = serde_json::from_str(r#"{"done":[true],"completed_choice":[null],"run_seed":5}"#).unwrap();
+        assert_eq!((p.next, p.carry.len()), (None, 0));
+    }
+
     #[test]
     fn two_clients_play_the_same_editor_campaign_mission_in_coop() {
         let doc = coop_doc();