new savegame loader is not quite working yet

src/net/torvald/terrarum/SavegameCollection.kt

@@ -1,5 +1,6 @@
 package net.torvald.terrarum
 
+import net.torvald.terrarum.App.printdbg
 import net.torvald.terrarum.savegame.DiskSkimmer
 import java.io.File
 
@@ -34,4 +35,118 @@ class SavegameCollection(files0: List<DiskSkimmer>) {
         return files.first()
     }
 
+}
+
+class SavegameCollectionPair(player: SavegameCollection?, world: SavegameCollection?) {
+
+    private lateinit var manualPlayer: DiskSkimmer
+    private lateinit var manualWorld: DiskSkimmer
+    private lateinit var autoPlayer: DiskSkimmer
+    private lateinit var autoWorld: DiskSkimmer
+
+    var status = 0 // 0: none available, 1: loadable manual save is newer than loadable auto; 2: loadable autosave is newer than loadable manual
+        private set
+
+    var newerSaveIsDamaged = false // only when most recent save is corrupted
+        private set
+
+    init {
+        printdbg(this, "init ($player, $world)")
+
+        if (player != null && world != null) {
+
+            printdbg(this, player.files.joinToString { it.diskFile.name })
+            printdbg(this, world.files.joinToString { it.diskFile.name })
+
+            // if a pair of files were saved successfully, they must have identical lastModifiedTime()
+            var pc = 0; val pt = player.files[0].getLastModifiedTime()
+            var wc = 0; val wt = world.files[0].getLastModifiedTime()
+            while (pc < player.files.size && wc < world.files.size) {
+                val pcf = player.files[pc]
+                val pcm = pcf.getLastModifiedTime()
+                val wcf = world.files[wc]
+                val wcm = wcf.getLastModifiedTime()
+
+                if (playerDiskNotDamaged(pcf) && worldDiskNotDamaged(wcf)) {
+                    when (pcf.isAutosaved().toInt(1) or wcf.isAutosaved().toInt()) {
+                        3 -> {
+                            autoPlayer = pcf
+                            autoWorld = wcf
+                            pc += 1
+                            wc += 1
+                        }
+                        0 -> {
+                            manualPlayer = pcf
+                            manualWorld = wcf
+                            pc += 1
+                            wc += 1
+                        }
+                        else -> {
+                            if (pcm > wcm)
+                                pc += 1
+                            else if (pcm == wcm) {
+                                pc += 1
+                                wc += 1
+                            }
+                            else
+                                wc += 1
+                        }
+                    }
+
+                }
+
+
+
+                if (::manualPlayer.isInitialized && ::manualWorld.isInitialized && ::autoPlayer.isInitialized && ::autoWorld.isInitialized)
+                    break
+            }
+
+            if (::manualPlayer.isInitialized && ::manualWorld.isInitialized && ::autoPlayer.isInitialized && ::autoWorld.isInitialized) {
+                status = if (manualPlayer.getLastModifiedTime() > autoPlayer.getLastModifiedTime()) 1 else 2
+
+                printdbg(this, "manualPlayer = ${manualPlayer.diskFile.path}")
+                printdbg(this, "manualWorld = ${manualWorld.diskFile.path}")
+                printdbg(this, "autoPlayer = ${autoPlayer.diskFile.path}")
+                printdbg(this, "autoWorld = ${autoWorld.diskFile.path}")
+            }
+            else if (::manualPlayer.isInitialized && ::manualWorld.isInitialized || ::autoPlayer.isInitialized && ::autoWorld.isInitialized) {
+                status = 1
+                if (::manualPlayer.isInitialized) {
+                    printdbg(this, "manualPlayer = ${manualPlayer.diskFile.path}")
+                    printdbg(this, "manualWorld = ${manualWorld.diskFile.path}")
+                }
+                else {
+                    printdbg(this, "autoPlayer = ${autoPlayer.diskFile.path}")
+                    printdbg(this, "autoWorld = ${autoWorld.diskFile.path}")
+                }
+            }
+            else {
+                status = 0
+            }
+        }
+    }
+
+    private fun DiskSkimmer.isAutosaved() = this.getSaveMode().and(0b0000_0010) != 0
+
+    private fun playerDiskNotDamaged(disk: DiskSkimmer): Boolean {
+        return true
+    }
+
+    private fun worldDiskNotDamaged(disk: DiskSkimmer): Boolean {
+        return true
+    }
+
+    fun moreRecentAutosaveAvailable() = (status == 2)
+    fun saveAvaliable() = (status > 0)
+
+    fun getManualSave(): Pair<DiskSkimmer, DiskSkimmer>? {
+        if (status == 0) return null
+        return manualPlayer to manualWorld
+    }
+
+    fun getAutoSave(): Pair<DiskSkimmer, DiskSkimmer>? {
+        if (status != 2) return null
+        return autoPlayer to autoWorld
+    }
+
 }