package greenfoot.util;

import java.io.File;
import java.util.ArrayList;
import java.util.List;

import bluej.Config;




| Represents a version number. A version is a sequence of numbers separated by
| full stops and an optional string at the end.
|
| @author Poul Henriksen
|
public class Version
{       



| A change in this number indicates a breaking change that will be likely
| to break some scenarios.
|
private int breakingNumber;

   
   


| A change in this number indicates a visible (to the user) change that
| should not break anything in most cases.
|
private int nonBreakingNumber;

   
   

| A change in this number indicates an internal change only.
|
private int internalNumber;

   
   

| The version number was bad or non-existent
|
private boolean badVersion = false;

   
   


| Create a new Version from the string.
|
| @param versionString A string in the format X.Y.Z. If the string is null
|            or invalid, it will be flagged and can be determined by
|            calling {}link #isBad()}.
|
public Version(String versionString)
   {
      if (versionString == null) {            
         badVersion = true;
           
         return;         
         }

      String[] split = versionString.split("\\.");
       
      List<Integer> numbers = new ArrayList<Integer>();

       
      String lastString = null;
       
      for (String s : split) {            
         try {
         numbers.add(Integer.valueOf(Integer.parseInt(s)));             
         }
           
      catch (NumberFormatException nfe) {                
         lastString = s;
               
         break;             
         };
      }

       
   
   
   if (numbers.size() < 3 && lastString != null) {            
      
      String[] endSplit = lastString.split("[^0-9]+");
           
      
      if (endSplit.length > 0) {                
         String candidate = endSplit[0];
               
         
         
         if (lastString.startsWith(candidate)) {
            numbers.add(Integer.valueOf(Integer.parseInt(candidate)));                 
            }             
         }         
      }

   if (numbers.size() == 3) {
      breakingNumber = numbers.get(0);
      nonBreakingNumber = numbers.get(1);
      internalNumber = numbers.get(2);         
      }
       

   else {
           
   badVersion = true;         
   }     
}

   



| True if this version number is older than the other version number in a
| way that will be likely to break some scenarios. Or if any of the
| versions is a bad version number.
|
public boolean isOlderAndBreaking(Version other)
   {        
   return this.breakingNumber < other.breakingNumber || this.badVersion || other.badVersion;     
   }

   



| True if this version number is older than the other version number and
| if our version is before 3.0.0 while the given version is later.
|
public boolean crosses300Boundary(Version other)
   {        
   return this.breakingNumber < other.breakingNumber && this.breakingNumber < 3 && other.breakingNumber >= 3;     
   }

   



| True if this version number is different than the other version number in
| a way that will be unlikely to break scenarios. Or if any of the versions
| is a bad version number.
|
public boolean isNonBreaking(Version other)
   {        
   return this.nonBreakingNumber != other.nonBreakingNumber || this.badVersion || other.badVersion;     
   }

   



| True if this version number is different than the other version number
| but will only contain in internal changes and will not break scenarios.
| Or if any of the versions is a bad version number.
|
public boolean isInternal(Version other)
   {        
   return this.internalNumber != other.internalNumber || this.badVersion || other.badVersion;     
   }

   



| True if the version number was not correctly formated.
|
public boolean isBad()
   {        
   return badVersion;     
   }

   



| Returns the version in the format X.Y.Z.
|
public String toString()
   {        
   return breakingNumber + "." + nonBreakingNumber + "." + internalNumber;     
   }

   



| Return a message that shows the changes introduced in apiVersion compared to this version.
|
| @param apiVersion The API version that for which the changes should be shown.
| @return
|
public String getChangesMessage(Version apiVersion)
   {        
   StringBuffer message = new StringBuffer(Config.getString("project.version.older.part1") + this
   + Config.getString("project.version.older.part2") + apiVersion
   + Config.getString("project.version.older.part3") + "\n\n");
        
       
   int changeNumber = 1;
   String changesString = Config.getString("project.version.changes." + changeNumber, "EMPTY").trim();
        
   while (!changesString.equals("EMPTY")) {
      int spaceIndex = changesString.indexOf(' ');
      if (spaceIndex < 5) {                
         
         return "";             
         }
      String versionString = changesString.substring(0,spaceIndex);
           
      Version changeVersion = new Version(versionString);
      if (this.isOlderAndBreaking(changeVersion)) {
         String text = changesString.substring(spaceIndex + 1);  
         message.append(text + "\n");             
         }
           
      changeNumber++;
      changesString = Config.getString("project.version.changes." + changeNumber, "EMPTY");         
      }
        

   return message.toString();     
   }

   



| This will return a message about the version being VERY old (before we
| introduced version numbers). This is very unlikely to ever be used.
|
public String getBadMessage()
   {
   return Config.getString("project.version.none");     
   }

   



| Return a message that says that this project is a newer version.
|
public String getNewerMessage()
   {
   return Config.getString("project.version.newer.part1") + this
   + Config.getString("project.version.newer.part2");     
   }

   



| Get message if this is not a Greenfoot version number.
|
public String getNotGreenfootMessage(File projectDir)
   {
   return Config.getString("project.version.notGreenfoot") + projectDir;     
   } 
}