/* Copyright (c) 2010 Daniel Doubrovkine, All Rights Reserved
 *
 * The contents of this file is dual-licensed under 2
 * alternative Open Source/Free licenses: LGPL 2.1 or later and
 * Apache License 2.0. (starting with JNA version 4.0.0).
 *
 * You can freely decide which license you want to apply to
 * the project.
 *
 * You may obtain a copy of the LGPL License at:
 *
 * http://www.gnu.org/licenses/licenses.html
 *
 * A copy is also included in the downloadable source code package
 * containing JNA, in file "LGPL2.1".
 *
 * You may obtain a copy of the Apache License at:
 *
 * http://www.apache.org/licenses/
 *
 * A copy is also included in the downloadable source code package
 * containing JNA, in file "AL2.0".
 */
package com.sun.jna.platform.win32;

import java.util.ArrayList;

import com.sun.jna.Native;
import com.sun.jna.platform.win32.Sspi.PSecPkgInfo;
import com.sun.jna.platform.win32.Sspi.SecPkgInfo;
import com.sun.jna.ptr.IntByReference;

/**
 * Secur32 Utility API.
 * @author dblock[at]dblock.org
 */
public abstract class Secur32Util {

    /**
     * An SSPI package.
     */
    public static class SecurityPackage {
        /**
         * Package name.
         */
        public String name;
        /**
         * Package comment.
         */
        public String comment;
    }

    /**
     * Retrieves the name of the user or other security principal associated
     * with the calling thread.
     *
     * @param format User name format.
     * @return User name in a given format.
     */
    public static String getUserNameEx(int format) {
        char[] buffer = new char[128];
        IntByReference len = new IntByReference(buffer.length);
        boolean result = Secur32.INSTANCE.GetUserNameEx(format, buffer, len);

        if (! result) {

            int rc = Kernel32.INSTANCE.GetLastError();

            switch(rc) {
                case W32Errors.ERROR_MORE_DATA:
                    buffer = new char[len.getValue() + 1];
                    break;
                default:
                    throw new Win32Exception(Native.getLastError());
            }

            result = Secur32.INSTANCE.GetUserNameEx(format, buffer, len);
        }

        if (! result) {
            throw new Win32Exception(Native.getLastError());
        }

        return Native.toString(buffer);
    }

    /**
     * Get the security packages installed on the current computer.
     * @return
     *  An array of SSPI security packages.
     */
    public static SecurityPackage[] getSecurityPackages() {
        IntByReference pcPackages = new IntByReference();
        PSecPkgInfo pPackageInfo = new PSecPkgInfo();
        int rc = Secur32.INSTANCE.EnumerateSecurityPackages(pcPackages, pPackageInfo);
        if (W32Errors.SEC_E_OK != rc) {
            throw new Win32Exception(rc);
        }
        SecPkgInfo[] packagesInfo = pPackageInfo.toArray(pcPackages.getValue());
        ArrayList<SecurityPackage> packages = new ArrayList<SecurityPackage>(pcPackages.getValue());
        for (SecPkgInfo packageInfo : packagesInfo) {
            SecurityPackage securityPackage = new SecurityPackage();
            securityPackage.name = packageInfo.Name.toString();
            securityPackage.comment = packageInfo.Comment.toString();
            packages.add(securityPackage);
        }
        rc = Secur32.INSTANCE.FreeContextBuffer(pPackageInfo.pPkgInfo.getPointer());
        if (W32Errors.SEC_E_OK != rc) {
            throw new Win32Exception(rc);
        }
        return packages.toArray(new SecurityPackage[0]);
    }
}
