Fix data migration not executing when data_version is outdated

core/src/main/java/github/nighter/smartspawner/migration/SpawnerDataMigration.java

@@ -1,6 +1,7 @@
 package github.nighter.smartspawner.migration;
 
 import github.nighter.smartspawner.SmartSpawner;
+import org.bukkit.configuration.ConfigurationSection;
 import org.bukkit.configuration.file.FileConfiguration;
 import org.bukkit.configuration.file.YamlConfiguration;
 
@@ -15,6 +16,13 @@ public class SpawnerDataMigration {
     private static final String DATA_FILE = "spawners_data.yml";
     private static final String BACKUP_FILE = "spawners_data_backup.yml";
     private static final String MIGRATION_FLAG = "data_version";
+    private static final int DEFAULT_MAX_STACK_SIZE = 10;
+    private static final int VERSION_3_SETTINGS_FIELD_COUNT = 13;
+    // Version 2 can have 11 or 12 fields (12 if allowEquipmentItems was included)
+    private static final int VERSION_2_MIN_SETTINGS_FIELD_COUNT = 11;
+    private static final int VERSION_2_MAX_SETTINGS_FIELD_COUNT = 12;
+    // Version 2 has first 10 fields before maxStackSize is inserted
+    private static final int VERSION_2_FIELDS_BEFORE_MAX_STACK = 10;
     private final int CURRENT_VERSION;
 
     public SpawnerDataMigration(SmartSpawner plugin) {
@@ -38,27 +46,58 @@ public boolean checkAndMigrateData() {
         try {
             needsMigration = false;
 
-            // Check if data_version exists
-            if (!config.contains(MIGRATION_FLAG)) {
-                config.set(MIGRATION_FLAG, CURRENT_VERSION);
-                try {
-                    config.save(dataFile);
-                } catch (IOException e) {
-                    plugin.getLogger().warning("Could not save data_version flag: " + e.getMessage());
-                }
+            // Check if data_version exists and compare with current version
+            int dataVersion = config.getInt(MIGRATION_FLAG, 0);
+
+            if (dataVersion == 0) {
+                // data_version doesn't exist, check the structure to determine if migration is needed
+                plugin.getLogger().info("No data_version found. Checking data structure...");
+                needsMigration = true;
+            } else if (dataVersion < CURRENT_VERSION) {
+                // data_version exists but is outdated
+                plugin.getLogger().info("Data version " + dataVersion + " is outdated. Current version is " + CURRENT_VERSION + ".");
+                needsMigration = true;
             }
 
-            // Validate the spawners section
-            if (config.contains("spawners")) {
-                for (String spawnerId : config.getConfigurationSection("spawners").getKeys(false)) {
-                    String spawnerPath = "spawners." + spawnerId;
-                    // Check if the spawner data is in the new format
-                    if (!config.contains(spawnerPath + ".location") ||
-                            !config.contains(spawnerPath + ".settings") ||
-                            !config.contains(spawnerPath + ".inventory")) {
-                        needsMigration = true;
-                        break;
+            // If version check indicates migration is needed, validate by checking structure
+            if (needsMigration && config.contains("spawners")) {
+                // Double-check by validating the spawners section structure
+                boolean hasNewFormat = true;
+                ConfigurationSection spawnersSection = config.getConfigurationSection("spawners");
+                if (spawnersSection != null) {
+                    for (String spawnerId : spawnersSection.getKeys(false)) {
+                        String spawnerPath = "spawners." + spawnerId;
+                        // Check if the spawner data is in the new format
+                        if (!config.contains(spawnerPath + ".location") ||
+                                !config.contains(spawnerPath + ".settings") ||
+                                !config.contains(spawnerPath + ".inventory")) {
+                            hasNewFormat = false;
+                            break;
+                        }
+
+                        // Also check if settings string has the correct number of fields for version 3
+                        String settingsString = config.getString(spawnerPath + ".settings");
+                        if (settingsString != null) {
+                            String[] settings = settingsString.split(",");
+                            // Version 3 requires 13 fields (including maxStackSize and isAtCapacity)
+                            if (settings.length < VERSION_3_SETTINGS_FIELD_COUNT) {
+                                hasNewFormat = false;
+                                break;
+                            }
+                        }
+                    }
+                }
+
+                // If structure is already in new format, just update version
+                if (hasNewFormat) {
+                    plugin.getLogger().info("Data structure is already in current format. Updating version flag...");
+                    config.set(MIGRATION_FLAG, CURRENT_VERSION);
+                    try {
+                        config.save(dataFile);
+                    } catch (IOException e) {
+                        plugin.getLogger().warning("Could not save data_version flag: " + e.getMessage());
                     }
+                    needsMigration = false;
                 }
             }
 
@@ -126,6 +165,17 @@ private void restoreFromBackup(File dataFile) {
 
     private boolean migrateData(FileConfiguration oldConfig, File dataFile) {
         try {
+            // Default to 0 to indicate no version set (older than version 1)
+            // This ensures all unversioned data goes through migration
+            int oldVersion = oldConfig.getInt(MIGRATION_FLAG, 0);
+
+            // Check if this is a version 2 to version 3 migration
+            if (oldVersion == 2 && oldConfig.contains("spawners")) {
+                plugin.getLogger().info("Migrating from version 2 to version 3...");
+                return migrateVersion2ToVersion3(oldConfig, dataFile);
+            }
+
+            // Otherwise, handle old format to new format migration
             // Create new data file
             FileConfiguration newConfig = new YamlConfiguration();
 
@@ -146,4 +196,65 @@ private boolean migrateData(FileConfiguration oldConfig, File dataFile) {
             return false;
         }
     }
+
+    private boolean migrateVersion2ToVersion3(FileConfiguration config, File dataFile) {
+        try {
+            ConfigurationSection spawnersSection = config.getConfigurationSection("spawners");
+            if (spawnersSection == null) {
+                plugin.getLogger().warning("No spawners section found in version 2 data");
+                return false;
+            }
+
+            int migratedCount = 0;
+            for (String spawnerId : spawnersSection.getKeys(false)) {
+                String settingsPath = "spawners." + spawnerId + ".settings";
+                String settingsString = config.getString(settingsPath);
+
+                if (settingsString != null) {
+                    String[] settings = settingsString.split(",");
+
+                    // Version 2 can have 11 or 12 fields (12 if allowEquipmentItems was included)
+                    if (settings.length >= VERSION_2_MIN_SETTINGS_FIELD_COUNT && 
+                        settings.length <= VERSION_2_MAX_SETTINGS_FIELD_COUNT) {
+                        // Migrate version 2 (11-12 fields) to version 3 (13 fields)
+                        // Version 2 (11): exp,active,range,stop,delay,maxLoot,maxExp,minMobs,maxMobs,stack,lastSpawnTime
+                        // Version 2 (12): exp,active,range,stop,delay,maxLoot,maxExp,minMobs,maxMobs,stack,lastSpawnTime,allowEquipmentItems
+                        // Version 3 (13): exp,active,range,stop,delay,maxLoot,maxExp,minMobs,maxMobs,stack,maxStack,lastSpawnTime,isAtCapacity
+
+                        // Get the default maxStackSize from config or use constant
+                        int defaultMaxStackSize = plugin.getConfig().getInt("spawner.max_stack_size", DEFAULT_MAX_STACK_SIZE);
+
+                        // Build new settings string with maxStackSize inserted at position 10
+                        StringBuilder newSettingsBuilder = new StringBuilder();
+                        for (int i = 0; i < VERSION_2_FIELDS_BEFORE_MAX_STACK; i++) {
+                            if (i > 0) newSettingsBuilder.append(",");
+                            newSettingsBuilder.append(settings[i]);
+                        }
+                        newSettingsBuilder.append(",").append(defaultMaxStackSize);  // maxStackSize (NEW at position 10)
+                        newSettingsBuilder.append(",").append(settings[10]);          // lastSpawnTime (moved from 10 to 11)
+                        // For isAtCapacity, use allowEquipmentItems if it exists (position 11 in 12-field version), otherwise false
+                        boolean isAtCapacity = settings.length == 12 ? Boolean.parseBoolean(settings[11]) : false;
+                        newSettingsBuilder.append(",").append(isAtCapacity);          // isAtCapacity (NEW at position 12)
+
+                        config.set(settingsPath, newSettingsBuilder.toString());
+                        migratedCount++;
+                    }
+                }
+            }
+
+            // Update version flag
+            config.set(MIGRATION_FLAG, CURRENT_VERSION);
+
+            // Save the updated config
+            config.save(dataFile);
+
+            plugin.getLogger().info("Successfully migrated " + migratedCount + " spawners from version 2 to version 3");
+            return true;
+
+        } catch (Exception e) {
+            plugin.getLogger().severe("Failed to migrate from version 2 to version 3: " + e.getMessage());
+            e.printStackTrace();
+            return false;
+        }
+    }
 }