import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

/**
 * Credential Repository for handling user credentials
 * @author Claudia Metzler
 */

public class CredentialRepository implements CredentialRepositoryInterface{

    private int idCounter = 0;
    private CredentialList credentials;

    /**
     * Konstruktor
     *
     * Initializes instance variable ArrayList
     */
    public CredentialRepository()
    {
        this.credentials = new CredentialList();
    }


    /**
     * Create a new Set of User credentials
     * @param name
     * @param password
     * @return size of repositoy - arraylist for checking
     */

    public int createNewCredential(String name, String password)
    {
        try {
            this.credentials.add(new Credential(name, password, this.idCounter++));
        }
        catch(Exception fail)
        {
            System.err.println(fail.getMessage());
        }

        return this.getListSize();
    }

    /**
     * Function to return a specific Credential via Name input
     * @param needle [ aka to-search-for ]
     * @return usercredential | NULL
     */

    @Override
    public Credential getCredentialsViaName(String needle) {

        for(int c = 0; c < this.getListSize(); c++)
        {
            Credential credential = this.credentials.get(c);

            if(credential.getName().equals(needle))
                return credential;
        }

        return null;
    }


    /**
     * Function to return a specific Credential via ID
     * @param id
     * @return usercredential | NULL
     */

    @Override
    public Credential getCredentialsViaId(int id) {

        try{
            return this.credentials.get(id);
        }
        catch (IndexOutOfBoundsException outOfBoundsException)
        {
           return null;
        }

    }

    /**
     * Function to update userpassword, assuming we already know the userid
     * @param index
     * @param newPassword
     */
    @Override
    public void updatePassword(int index, String newPassword) {

        try{
            this.credentials.get(index).upDatePassword(newPassword);
        }
        catch (IndexOutOfBoundsException outOfBoundsException)
        {
            System.err.println("No Credential with Index" + index + " found");
        }

    }


    /**
     * Function to update username analoge to updatePassword
     * @param index
     * @param newUsername
     */
    public void updateUsername(int index, String newUsername){

        try{
            this.credentials.get(index).updateUsername(newUsername);
        }
        catch (IndexOutOfBoundsException outOfBoundsException)
        {
            System.err.println("No Credential with Index" + index + " found");
        }
    }

    /**
     * Deletion function for credentials
     * Will immediately delete - double check for user permission
     * @param index
     */
    @Override
    public void delete(int index) {

        this.credentials.remove(index);

    }

    /**
     * Function for serialization of all Credentials
     * @param fileName
     */

    public void serializeObject(String fileName)
    {
        if(fileName.equals("")) return;

        try {
            FileOutputStream file = new FileOutputStream(this.getWorkingDirectory() + fileName + ".claud11");
            ObjectOutputStream out = new ObjectOutputStream(file);
            out.writeObject(this.credentials);
        } catch (Exception fail) {
            System.err.println("Serialization failed!");
            fail.printStackTrace();
        }
    }

    /**
     * Function to load serialized Objects from hard drive by path
     * @param fileName
     */
    public void deserializeObjects(String fileName)
    {
        if(fileName.equals("")) return;

        try {
            FileInputStream file = new FileInputStream(this.getWorkingDirectory() + fileName + ".claud11");
            ObjectInputStream in = new ObjectInputStream(file);

            this.credentials = (CredentialList)in.readObject();

            in.close();
            file.close();

        } catch(Exception fail)
        {
            System.err.println("Loading of CredentialRepository failed");
        }
    }

    /**
     * helper function to check list size after insertion / deletion
     * @return
     */

    private int getListSize()
    {
        return this.credentials.size();
    }

    /**
     * Helper function for serialization
      * @return
     */

    private String getWorkingDirectory()
    {
        return System.getProperty("user.dir");
    }

    public CredentialList getCredentialList() {
        return credentials;
    }

}