Optimise files on start

Sources/App/Management/DiskWriter.swift

@@ -8,15 +8,27 @@
 import Foundation
 
 
-protocol DiskWriter {
+protocol DiskWriter: AnyObject {
     
-    var storageFile: FileHandle { get }
+    var storageFile: FileHandle { get set }
     
     var storageFileUrl: URL { get }
 }
 
 extension DiskWriter {
 
+    func replaceFile(data: String) throws {
+        let data = data.data(using: .utf8)!
+        try storageFile.close()
+        try data.write(to: storageFileUrl)
+        storageFile = try FileHandle(forUpdating: storageFileUrl)
+        if #available(macOS 10.15.4, *) {
+            try storageFile.seekToEnd()
+        } else {
+            storageFile.seekToEndOfFile()
+        }
+    }
+    
     static func prepareFile(at url: URL) throws -> FileHandle {
         if !FileManager.default.fileExists(atPath: url.path) {
             try Data().write(to: url)

Sources/App/Management/PlayerManagement.swift

@@ -16,7 +16,7 @@ final class PlayerManagement: DiskWriter {
     /// A reverse mapping between generated access tokens and player name
     private var playerNameForToken = [SessionToken: PlayerName]()
     
-    let storageFile: FileHandle
+    var storageFile: FileHandle
     
     let storageFileUrl: URL
 
@@ -26,6 +26,7 @@ final class PlayerManagement: DiskWriter {
         storageFileUrl = url
         storageFile = try Self.prepareFile(at: url)
 
+        var redundantEntries = 0
         try readLinesFromDisk().forEach { line in
             let parts = line.components(separatedBy: ":")
             // Token may contain the separator
@@ -37,12 +38,29 @@ final class PlayerManagement: DiskWriter {
             let token = parts.dropFirst().joined(separator: ":")
             if token == "" {
                 playerPasswordHashes[name] = nil
-            } else {
-                playerPasswordHashes[name] = token
+                redundantEntries += 2 // One for creation, one for deletion
+                return
             }
+            if playerPasswordHashes[name] != nil {
+                redundantEntries += 1
+            }
+            playerPasswordHashes[name] = token
         }
         
-        print("Loaded \(playerPasswordHashes.count) players")
+        let playerCount = playerPasswordHashes.count
+        let totalEntries = playerCount + redundantEntries
+        let percentage = playerCount * 100 / totalEntries
+        print("Loaded \(playerCount) players from \(totalEntries) entries (\(percentage) % useful)")
+        if percentage < 80 && redundantEntries > 10 {
+            try optimizePlayerFile()
+        }
+    }
+
+    private func optimizePlayerFile() throws {
+        print("Optimizing player file...")
+        let lines = playerPasswordHashes.map { $0.key + ":" + $0.value + "\n" }.joined()
+        try replaceFile(data: lines)
+        print("Done.")
     }
     
     private func save(password: PasswordHash, forPlayer player: PlayerName) -> Bool {

Sources/App/Management/TableManagement.swift

@@ -13,7 +13,7 @@ final class TableManagement: DiskWriter {
     private var tables = [TableId : ManageableTable]()
     
     /// The handle to the file where the tables are persisted
-    let storageFile: FileHandle
+    var storageFile: FileHandle
     
     /// The url to the file where the tables are persisted
     let storageFileUrl: URL
@@ -30,6 +30,7 @@ final class TableManagement: DiskWriter {
         storageFile = try Self.prepareFile(at: url)
         
         var entries = [TableId : (name: TableName, isPublic: Bool, players: [PlayerName])]()
+        var redundantEntries = 0
         try readLinesFromDisk().forEach { line in
             // Each line has parts: ID | NAME | PLAYER, PLAYER, ...
             let parts = line.components(separatedBy: ":")
@@ -43,14 +44,37 @@ final class TableManagement: DiskWriter {
             let players = parts[3].components(separatedBy: ",")
             if name == "" {
                 entries[id] = nil
-            } else {
-                entries[id] = (name, isPublic, players)
+                redundantEntries += 2 // One for creation, one for deletion
+                return
             }
+            if entries[id] != nil {
+                redundantEntries += 1
+            }
+            entries[id] = (name, isPublic, players)
         }
         entries.forEach { id, tableData in
             tables[id] = WaitingTable(id: id, name: tableData.name, isPublic: tableData.isPublic, players: tableData.players)
         }
-        print("Loaded \(tables.count) tables")
+        let totalEntries = entries.count + redundantEntries
+        let percentage = entries.count * 100 / totalEntries
+        print("Loaded \(tables.count) tables from \(totalEntries) entries (\(percentage) % useful)")
+        if percentage < 80  && redundantEntries > 10 {
+            try optimizeTableFile()
+        }
+    }
+
+    private func optimizeTableFile() throws {
+        print("Optimizing tables file...")
+        let lines = tables.values.map(entry).joined(separator: "\n") + "\n"
+        try replaceFile(data: lines)
+        print("Done.")
+    }
+
+    private func entry(for table: ManageableTable) -> String {
+        let visible = table.isPublic ? "public" : "private"
+        let players = table.playerNames
+            .joined(separator: ",")
+        return [table.id, table.name, visible, players].joined(separator: ":")
     }
     
     /**
@@ -62,11 +86,7 @@ final class TableManagement: DiskWriter {
      */
     @discardableResult
     private func writeTableToDisk(table: ManageableTable) -> Bool {
-        let visible = table.isPublic ? "public" : "private"
-        let players = table.playerNames
-            .joined(separator: ",")
-        let entry = [table.id, table.name, visible, players]
-            .joined(separator: ":")
+        let entry = entry(for: table)
         return writeToDisk(line: entry)
     }
     
@@ -187,6 +207,9 @@ final class TableManagement: DiskWriter {
         }
         tables[newTable.id] = newTable
         newTable.sendUpdateToAllPlayers()
+        if newTable is FinishedTable || newTable is DealingTable {
+            writeTableToDisk(table: newTable)
+        }
         return .success
     }