/*************************************************************************
 *                                                                       *
 *  CESeCore: CE Security Core                                           *
 *                                                                       *
 *  This software is free software; you can redistribute it and/or       *
 *  modify it under the terms of the GNU Lesser General Public           *
 *  License as published by the Free Software Foundation; either         *
 *  version 2.1 of the License, or any later version.                    *
 *                                                                       *
 *  See terms of license at gnu.org.                                     *
 *                                                                       *
 *************************************************************************/
package org.cesecore.authentication.tokens;

import java.io.Serializable;
import java.security.Principal;
import java.util.Arrays;
import java.util.HashSet;

import org.cesecore.authentication.AuthenticationFailedException;
import org.cesecore.authorization.user.AccessUserAspect;

/**
 * AuthenticationToken representing a user that has provided no means of authentication,
 * e.g. a client accessing an interface like public RA web pages.
 * 
 * @version $Id: PublicAccessAuthenticationToken.java 26057 2017-06-22 08:08:34Z anatom $
 */
public class PublicAccessAuthenticationToken extends NestableAuthenticationToken {

    /** Public access to the RA. Compare to PublicWebPrincipal which serves the same purpose, but is used in the PublicWeb */
    public static class PublicAccessPrincipal implements Principal, Serializable {
        private static final long serialVersionUID = 1L;
        private final String principal;

        public PublicAccessPrincipal(final String principal) {
            this.principal = principal;
        }

        @Override
        public String getName() {
            return principal;
        }
    }

    private static class PublicAccessCredential implements Serializable {
        private static final long serialVersionUID = 1L;
        private final boolean confidentialTransport;

        public PublicAccessCredential(final boolean confidentialTransport) {
            this.confidentialTransport = confidentialTransport;
        }

        public boolean isConfidentialTransport() {
            return confidentialTransport;
        }
    }

    private static final long serialVersionUID = 1L;
    public static final PublicAccessAuthenticationTokenMetaData metaData = new PublicAccessAuthenticationTokenMetaData();
    
    private final PublicAccessPrincipal principal;
    private final PublicAccessCredential credential;

    @Deprecated
    public PublicAccessAuthenticationToken(final String principal) {
        this(principal, false);
    }

    public PublicAccessAuthenticationToken(final String principal, final boolean confidentialTransport) {
        super(new HashSet<>(Arrays.asList(new PublicAccessPrincipal(principal))),
                new HashSet<>(Arrays.asList(new PublicAccessCredential(confidentialTransport))));
        this.principal = new PublicAccessPrincipal(principal);
        this.credential = new PublicAccessCredential(confidentialTransport);
    }

    @Override
    public boolean matches(AccessUserAspect accessUser) throws AuthenticationFailedException {
        // Protect against spoofing by checking if this token was created locally
        if (!super.isCreatedInThisJvm()) {
            return false;
        }
        if (!matchTokenType(accessUser.getTokenType())) {
            return false;
        }
        final PublicAccessMatchValue matchValue = (PublicAccessMatchValue) getMatchValueFromDatabaseValue(accessUser.getMatchWith());
        switch (matchValue) {
        case TRANSPORT_CONFIDENTIAL:
            return credential.isConfidentialTransport();
        case TRANSPORT_PLAIN:
            return !credential.isConfidentialTransport();
        case TRANSPORT_ANY:
            return true;
        default:
            return false;
        }
    }
    
    @Override
    public int getPreferredMatchKey() {
        return AuthenticationToken.NO_PREFERRED_MATCH_KEY; // not applicable to this type of authentication token
    }
    
    @Override
    public String getPreferredMatchValue() {
        return null;
    }

    /** Returns information of the entity this authentication token belongs to. */
    @Override
    public String toString() {
        return super.toString();
    }

    /** Override the default Principal.getName() when doing toString on this object. */
    @Override
    protected String toStringOverride() {
        return principal.getName() + (credential.isConfidentialTransport() ? " (TRANSPORT_CONFIDENTIAL)" : " (TRANSPORT_PLAIN)");
    }

    @Override
    public int hashCode() {
        int hashCode = 4711 * 1 + ((principal.getName() == null) ? 0 : principal.getName().hashCode());
        hashCode *= 17 + (credential.isConfidentialTransport() ? 0 : 1);
        return hashCode;
    }

    @Override
    public boolean equals(final Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        PublicAccessAuthenticationToken other = (PublicAccessAuthenticationToken) obj;
        if (principal.getName() == null) {
            if (other.principal.getName() != null) {
                return false;
            }
        } else if (!principal.getName().equals(other.principal.getName())) {
            return false;
        }
        return credential.isConfidentialTransport()==other.credential.isConfidentialTransport();
    }

    @Override
    protected String generateUniqueId() {
        return generateUniqueId(super.isCreatedInThisJvm(), principal.getName(), credential.isConfidentialTransport()) + ";" + super.generateUniqueId();
    }

    @Override
    public AuthenticationTokenMetaData getMetaData() {
        return metaData;
    }
}