Added new ExperienceFormula config and /mcconvert command

src/main/java/com/gmail/nossr50/util/commands/CommandRegistrationManager.java

@@ -21,6 +21,7 @@ import com.gmail.nossr50.commands.database.McpurgeCommand;
 import com.gmail.nossr50.commands.database.McremoveCommand;
 import com.gmail.nossr50.commands.database.MmoshowdbCommand;
 import com.gmail.nossr50.commands.database.MmoupdateCommand;
+import com.gmail.nossr50.commands.database.McconvertCommand;
 import com.gmail.nossr50.commands.experience.AddlevelsCommand;
 import com.gmail.nossr50.commands.experience.AddxpCommand;
 import com.gmail.nossr50.commands.experience.MmoeditCommand;
@@ -291,6 +292,15 @@ public final class CommandRegistrationManager {
         command.setExecutor(new MmoshowdbCommand());
     }
 
+    private static void registerMcconvertCommand() {
+        PluginCommand command = mcMMO.p.getCommand("mcconvert");
+        command.setDescription(LocaleLoader.getString("Commands.Description.mcconvert"));
+        command.setPermission("mcmmo.commands.mcconvert");
+        command.setPermissionMessage(permissionsMessage);
+        command.setUsage(LocaleLoader.getString("Commands.Usage.0", "mcconvert"));
+        command.setExecutor(new McconvertCommand());
+    }
+
     private static void registerAdminChatCommand() {
         PluginCommand command = mcMMO.p.getCommand("adminchat");
         command.setDescription(LocaleLoader.getString("Commands.Description.adminchat"));
@@ -432,6 +442,7 @@ public final class CommandRegistrationManager {
         registerMcremoveCommand();
         registerMmoupdateCommand();
         registerMmoshowdbCommand();
+        registerMcconvertCommand();
 
         // Experience Commands
         registerAddlevelsCommand();

src/main/java/com/gmail/nossr50/util/experience/FormulaManager.java

@@ -0,0 +1,192 @@
+package com.gmail.nossr50.util.experience;
+
+import java.io.File;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.bukkit.configuration.file.YamlConfiguration;
+
+import com.gmail.nossr50.config.Config;
+import com.gmail.nossr50.config.experience.ExperienceConfig;
+import com.gmail.nossr50.datatypes.experience.FormulaType;
+import com.gmail.nossr50.datatypes.skills.SkillType;
+import com.gmail.nossr50.mcMMO;
+
+public class FormulaManager {
+    private final mcMMO plugin;
+    private static String formulaFilePath = mcMMO.getFlatFileDirectory() + "formula.yml";
+    private static File formulaFile = new File(formulaFilePath);
+
+    // Experience needed to reach a level, cached values to improve conversion speed
+    private final Map<Integer, Integer> experienceNeededLinear = new HashMap<Integer, Integer>();
+    private final Map<Integer, Integer> experienceNeededExponential = new HashMap<Integer, Integer>();
+
+    private FormulaType previousFormula;
+
+    public FormulaManager(final mcMMO plugin) {
+        this.plugin = plugin;
+
+        loadFormula();
+    }
+
+    /**
+     * Get the formula type that was used before converting
+     *
+     * @return previously used formula type
+     */
+    public FormulaType getPreviousFormulaType() {
+        return previousFormula;
+    }
+
+    /**
+     * Set the formula type that was used before converting
+     *
+     * @param previousFormulaType The {@link FormulaType} previously used
+     */
+    public void setPreviousFormulaType(FormulaType previousFormulaType) {
+        this.previousFormula = previousFormulaType;
+    }
+
+    /**
+     * Calculate the total amount of experience earned based on
+     * the amount of levels and experience, using the previously
+     * used formula type.
+     *
+     * @param oldExperienceValues level and experience amount
+     * @return The total amount of experience
+     */
+    public int calculateTotalExperience(int[] oldExperienceValues) {
+        int totalXP = 0;
+
+        int skillLevel = oldExperienceValues[0];
+        int skillXPLevel = oldExperienceValues[1];
+
+        for (int level = 0; level < skillLevel; level++) {
+            totalXP += getCachedXpToLevel(level, previousFormula);
+        }
+        totalXP += skillXPLevel;
+
+        return totalXP;
+    }
+
+    /**
+     * Calculate how many levels a player should have using
+     * the new formula type.
+     *
+     * @param skillType skill where new levels and experience are calculated for
+     * @param experience total amount of experience
+     * @param formulaType The new {@link FormulaType}
+     * @return the amount of levels and experience
+     */
+    public int[] calculateNewLevel(SkillType skillType, int experience, FormulaType formulaType) {
+        int[] newExperienceValues = new int[2];
+        int newLevel = 0;
+        int remainder = 0;
+        int maxLevel = Config.getInstance().getLevelCap(skillType);
+
+        while (experience > 0 && newLevel < maxLevel) {
+            int experienceToNextLevel = getCachedXpToLevel(newLevel, formulaType);
+            if (experience - experienceToNextLevel >= 0) {
+                newLevel++;
+                experience -= experienceToNextLevel;
+            }
+            else {
+                remainder = experience;
+                break;
+            }
+        }
+        newExperienceValues[0] = newLevel;
+        newExperienceValues[1] = remainder;
+        return newExperienceValues;
+    }
+
+    /**
+     * Get the cached amount of experience needed to reach the next level,
+     * if cache doesn't contain the given value it is calculated and added
+     * to the cached data.
+     *
+     * @param level level to check
+     * @param formulaType The {@link FormulaType} used
+     * @return amount of experience needed to reach next level
+     */
+    public int getCachedXpToLevel(int level, FormulaType formulaType) {
+        int experience;
+
+        switch (formulaType) {
+            case UNKNOWN:
+            case LINEAR:
+                if (experienceNeededLinear.containsKey(level)) {
+                    experience = experienceNeededLinear.get(level);
+                    return experience;
+                }
+
+                double multiplier = ExperienceConfig.getInstance().getLinearMultiplier();
+                if (multiplier <= 0) {
+                    multiplier = 20;
+                }
+
+                experience = (int) Math.floor(ExperienceConfig.getInstance().getLinearBase() + level * multiplier);
+                experienceNeededLinear.put(level, experience);
+                return experience;
+
+            case EXPONENTIAL:
+                if (experienceNeededExponential.containsKey(level)) {
+                    experience = experienceNeededExponential.get(level);
+                    return experience;
+                }
+
+                multiplier = ExperienceConfig.getInstance().getExponentialMultiplier();
+                double exponent = ExperienceConfig.getInstance().getExponentialExponent();
+                int base = ExperienceConfig.getInstance().getExponentialBase();
+
+                if (multiplier <= 0) {
+                    multiplier = 0.1;
+                }
+
+                if (exponent <= 0) {
+                    exponent = 1.80;
+                }
+
+                experience = (int) Math.floor(multiplier * Math.pow(level, exponent) + base);
+                experienceNeededExponential.put(level, experience);
+                return experience;
+
+            default:
+                return 0;
+        }
+    }
+
+    /**
+     * Load formula file.
+     */
+    public void loadFormula() {
+        if (!formulaFile.exists()) {
+            previousFormula = FormulaType.UNKNOWN;
+            return;
+        }
+
+        YamlConfiguration formulasFile = YamlConfiguration.loadConfiguration(formulaFile);
+
+        previousFormula = FormulaType.getFormulaType(formulasFile.getString("Previous_Formula", "UNKNOWN"));
+    }
+
+    /**
+     * Save formula file.
+     */
+    public void saveFormula() {
+        if (formulaFile.exists()) {
+            formulaFile.delete();
+        }
+
+        YamlConfiguration formulasFile = new YamlConfiguration();
+
+        formulasFile.set("Previous_Formula", previousFormula.toString());
+
+        try {
+            formulasFile.save(formulaFile);
+        }
+        catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}