Replace public distribution with winner claim lifecycle

contracts/geev-core/src/test.rs

@@ -5972,3 +5972,130 @@ fn test_midflight_fee_change_does_not_alter_collected_fees() {
     });
     assert_eq!(collected_after, collected_before);
 }
+
+// ── Additional edge-case tests ────────────────────────────────────────────────
+
+/// `pick_winner` must emit a `GiveawayWinnerSelected` event whose data vec
+/// carries the correct `giveaway_id` and gross `prize_amount` (before the
+/// per-claim fee deduction).  The topics are `["giveaway", "winner", <winner>]`.
+#[test]
+fn test_pick_winner_emits_winner_selected_event() {
+    let env = Env::default();
+    env.mock_all_auths();
+
+    let (contract_id, client, _tc, token, creator) = setup_giveaway_env(&env, 100); // 1 %
+
+    let amount: i128 = 500;
+    let giveaway_id = client.create_giveaway(
+        &creator,
+        &token,
+        &amount,
+        &String::from_str(&env, "Winner Event"),
+        &60,
+        &1,
+        &None,
+        &None, // fee_bps
+    );
+
+    let winner = Address::generate(&env);
+    client.enter_giveaway(&winner, &giveaway_id);
+    env.ledger().with_mut(|li| li.timestamp += 100);
+    client.pick_winner(&giveaway_id);
+
+    let events = env.events().all();
+    // Topics: symbol "giveaway", symbol "winner", winner address.
+    let expected_topics: soroban_sdk::Vec<Val> = vec![
+        &env,
+        Symbol::new(&env, "giveaway").into_val(&env),
+        Symbol::new(&env, "winner").into_val(&env),
+        winner.into_val(&env),
+    ];
+    assert!(
+        events.iter().any(|(ec, topics, data)| {
+            if ec != contract_id || topics != expected_topics.into_val(&env) {
+                return false;
+            }
+            let v: soroban_sdk::Vec<Val> = soroban_sdk::Vec::from_val(&env, &data);
+            let ev_giveaway_id = u64::from_val(&env, &v.get(0).unwrap());
+            // prize_amount is the gross share — equal to `amount` for a single winner.
+            let ev_prize = i128::from_val(&env, &v.get(1).unwrap());
+            ev_giveaway_id == giveaway_id && ev_prize == amount
+        }),
+        "GiveawayWinnerSelected event not found or fields do not match"
+    );
+}
+
+/// For a 3-winner giveaway where only winner-0 claims before the deadline,
+/// `recover_unclaimed_prize` must return exactly the two unclaimed gross shares
+/// to the creator with no fee deduction, and the contract must retain only the
+/// fee collected from the single successful claim.
+#[test]
+fn test_partial_claim_creator_receives_exact_unclaimed_gross_shares() {
+    let env = Env::default();
+    env.mock_all_auths();
+
+    // 1 % fee so arithmetic is easy to track.
+    let (contract_id, client, tc, token, creator) = setup_giveaway_env(&env, 100);
+
+    // 3 winners, 300 tokens → 100 gross each (even split, no remainder).
+    let amount: i128 = 300;
+    let giveaway_id = client.create_giveaway(
+        &creator,
+        &token,
+        &amount,
+        &String::from_str(&env, "Partial 3-winner"),
+        &60,
+        &3,
+        &None,
+        &None, // fee_bps
+    );
+
+    let p1 = Address::generate(&env);
+    let p2 = Address::generate(&env);
+    let p3 = Address::generate(&env);
+    client.enter_giveaway(&p1, &giveaway_id);
+    client.enter_giveaway(&p2, &giveaway_id);
+    client.enter_giveaway(&p3, &giveaway_id);
+    env.ledger().with_mut(|li| li.timestamp += 100);
+    client.pick_winner(&giveaway_id);
+
+    let winners: Vec<Address> = env.as_contract(&contract_id, || {
+        env.storage()
+            .persistent()
+            .get::<DataKey, Giveaway>(&DataKey::Giveaway(giveaway_id))
+            .unwrap()
+            .winners
+            .clone()
+    });
+
+    // Only winner-0 claims (gross share = 100, net = 99, fee = 1).
+    client.claim_prize(&giveaway_id, &winners.get(0).unwrap());
+    assert_eq!(tc.balance(&winners.get(0).unwrap()), 99);
+
+    let creator_before = tc.balance(&creator);
+
+    // Advance past claim window.
+    env.ledger()
+        .with_mut(|li| li.timestamp += 7 * 24 * 60 * 60 + 1);
+    client.recover_unclaimed_prize(&giveaway_id, &creator);
+
+    // Creator recovers the two unclaimed gross shares (100 + 100 = 200) — no fee.
+    assert_eq!(tc.balance(&creator) - creator_before, 200);
+
+    // Contract holds only the 1-token fee from the single claim.
+    assert_eq!(tc.balance(&contract_id), 1);
+
+    // Unclaiming winners received nothing.
+    assert_eq!(tc.balance(&winners.get(1).unwrap()), 0);
+    assert_eq!(tc.balance(&winners.get(2).unwrap()), 0);
+
+    // Giveaway is finalized.
+    env.as_contract(&contract_id, || {
+        let g: Giveaway = env
+            .storage()
+            .persistent()
+            .get(&DataKey::Giveaway(giveaway_id))
+            .unwrap();
+        assert_eq!(g.status, GiveawayStatus::Completed);
+    });
+}