Flush progression only while server is idle

gamemode/sv_progression.lua

@@ -2,6 +2,7 @@ if not SERVER then return end
 
 local Progression = CustomCoopProgression
 local playerStates = setmetatable({}, { __mode = "k" })
+local disconnectedStates = {}
 local requestCooldowns = setmetatable({}, { __mode = "k" })
 local shopPrices = {}
 local dirtyShopPrices = {}
@@ -190,6 +191,17 @@ local function LoadPlayer(ply)
     local steamID64 = ply:SteamID64()
     if not steamID64 or steamID64 == "" then return end
 
+    -- A reconnect can happen before an idle write. Reuse the newer in-memory
+    -- state instead of replacing it with the older database snapshot.
+    local disconnectedState = disconnectedStates[steamID64]
+    if disconnectedState then
+        disconnectedStates[steamID64] = nil
+        disconnectedState.playerName = ply:Nick()
+        playerStates[ply] = disconnectedState
+        SyncPlayer(ply, disconnectedState)
+        return disconnectedState
+    end
+
     local row = Query(
         "SELECT lifetime_score, credits, equipped_model, equipped_weapon " ..
         "FROM custom_coop_players WHERE steamid64 = " .. SQLString(steamID64) .. " LIMIT 1",
@@ -352,15 +364,26 @@ local function FlushDirtyProgression()
         SavePlayerState(ply, state)
     end
 
+    for steamID64, state in pairs(disconnectedStates) do
+        if SavePlayerState(nil, state) then
+            disconnectedStates[steamID64] = nil
+        end
+    end
+
     SaveDirtyShopPrices()
 end
 
+local function FlushProgressionWhenServerIsEmpty()
+    if #player.GetHumans() > 0 then return end
+    FlushDirtyProgression()
+end
+
 local function StartProgressionSaveTimer()
     timer.Create(
         "CustomCoopProgressionSaveTotals",
         math.max(totalsSaveInterval:GetFloat(), 10),
         0,
-        FlushDirtyProgression
+        FlushProgressionWhenServerIsEmpty
     )
 end
 
@@ -659,9 +682,15 @@ hook.Add("PlayerInitialSpawn", "CustomCoopProgressionLoad", function(ply)
 end)
 
 hook.Add("PlayerDisconnected", "CustomCoopProgressionForget", function(ply)
-    SavePlayerState(ply, playerStates[ply])
+    local state = playerStates[ply]
+    if state and (state.profileDirty or next(state.pendingOwnedItems) ~= nil) then
+        disconnectedStates[state.steamID64] = state
+    end
+
     playerStates[ply] = nil
     requestCooldowns[ply] = nil
+
+    timer.Simple(0, FlushProgressionWhenServerIsEmpty)
 end)
 
 hook.Add("ShutDown", "CustomCoopProgressionSaveOnShutdown", function()