package bo;

import myjdbc.DatabaseOperation;
import struts.actionform.LoginForm;
import java.util.List;
import util.uid.UUIDGener;
import util.Util;

public class LoginBo {
    private static LoginBo bo = null;
    private static DatabaseOperation db = null;
    private LoginBo() {
        db = DatabaseOperation.getInstance();
    }

    public static LoginBo getInstance() {
        if (bo == null) {
            return new LoginBo();
        } else {
            return bo;
        }
    }

    /**
     * 用戶登陸驗證
     * @param form LoginForm
     * @return String
     */
    public String verifyUser(LoginForm form) {
        String name = Util.convertEncoding(form.getUsername());
        String pw = Util.convertEncoding(form.getPassword());
        StringBuffer sb = new StringBuffer();
        sb.append("select password , name from users where name = '" + name +
                  "' ");
        List result = db.executeSQL(sb.toString());
        if (result.size() == 0) {
            return "用戶名輸入有誤！";
        }
        String pwFromDb = (String) ((Object[]) result.get(0))[0];
        if (!pw.equals(pwFromDb)) {
            return "密碼輸入有誤！";
        }
        return "";
    }

    /**
     * 添加一個新的用戶
     * @param form LoginForm
     * @return String
     */
    public String addUser(LoginForm form) {

        StringBuffer sb = new StringBuffer();
        sb.append("insert into users values ('" + UUIDGener.getUUID() + "',");
        sb.append("'" + Util.convertEncoding(form.getUsers().getName()) + "',");
        sb.append("'" + Util.convertEncoding(form.getUsers().getPassword()) + "',");
        sb.append("'" + Util.convertEncoding(form.getUsers().getPhone()) + "',");
        sb.append("'" + Util.convertEncoding(form.getUsers().getAddress()) + "',");
        sb.append("'" + Util.convertEncoding(form.getUsers().getEmail()) + "')");
        db.executeSQL(sb.toString());
        return "";
    }

    /**
     * 驗證是否有重復的用戶名
     * @param form LoginForm
     * @return boolean
     */
    public boolean isExist(LoginForm form) {
        StringBuffer sb = new StringBuffer();
        sb.append("select * from users where name = '" +
                  form.getUsers().getName() + "'");
        List result = db.executeSQL(sb.toString());
        if (result.size() != 0) {
            return true;
        } else {
            return false;
        }

    }

}