/*

 * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package jdk.xml.internal;

import javax.xml.XMLConstants;

import static jdk.xml.internal.JdkXmlUtils.OVERRIDE_PARSER;

import static jdk.xml.internal.JdkXmlUtils.SP_USE_CATALOG;

import static jdk.xml.internal.JdkXmlUtils.RESET_SYMBOL_TABLE;

/**

 * This class manages JDK's XML Features. Previously added features and properties

 * may be gradually moved to this class.

 */

public class JdkXmlFeatures {

    public static final String ORACLE_JAXP_PROPERTY_PREFIX =

        "http://www.oracle.com/xml/jaxp/properties/";

    public static final String XML_FEATURE_MANAGER =

            ORACLE_JAXP_PROPERTY_PREFIX + "XmlFeatureManager";

    public static final String ORACLE_FEATURE_SERVICE_MECHANISM =

            "http://www.oracle.com/feature/use-service-mechanism";

    /**

     * Feature enableExtensionFunctions

     */

    public static final String ORACLE_ENABLE_EXTENSION_FUNCTION =

            ORACLE_JAXP_PROPERTY_PREFIX + "enableExtensionFunctions";

    public static final String SP_ENABLE_EXTENSION_FUNCTION =

            "javax.xml.enableExtensionFunctions";

    // This is the correct name by the spec

    public static final String SP_ENABLE_EXTENSION_FUNCTION_SPEC =

            "jdk.xml.enableExtensionFunctions";

    public static final String CATALOG_FEATURES = "javax.xml.catalog.catalogFeatures";

    public final static String PROPERTY_USE_CATALOG = XMLConstants.USE_CATALOG;

    public static enum XmlFeature {

        /**

         * Feature enableExtensionFunctions

         * FSP: extension function is enforced by FSP. When FSP is on, extension

         * function is disabled.

         */

        ENABLE_EXTENSION_FUNCTION(ORACLE_ENABLE_EXTENSION_FUNCTION, SP_ENABLE_EXTENSION_FUNCTION_SPEC,

                ORACLE_ENABLE_EXTENSION_FUNCTION, SP_ENABLE_EXTENSION_FUNCTION,

                true, false, true, true),

        /**

         * The {@link javax.xml.XMLConstants.USE_CATALOG} feature.

         * FSP: USE_CATALOG is not enforced by FSP.

         */

        USE_CATALOG(PROPERTY_USE_CATALOG, SP_USE_CATALOG,

                null, null,

                true, false, true, false),

        /**

         * Feature resetSymbolTable

         * FSP: RESET_SYMBOL_TABLE_FEATURE is not enforced by FSP.

         */

        RESET_SYMBOL_TABLE_FEATURE(RESET_SYMBOL_TABLE, RESET_SYMBOL_TABLE,

                null, null,

                false, false, true, false),

        /**

         * Feature overrideDefaultParser

         * FSP: not enforced by FSP.

         */

        JDK_OVERRIDE_PARSER(OVERRIDE_PARSER, OVERRIDE_PARSER,

                ORACLE_FEATURE_SERVICE_MECHANISM, ORACLE_FEATURE_SERVICE_MECHANISM,

                false, false, true, false);

        private final String name;

        private final String nameSP;

        private final String nameOld;

        private final String nameOldSP;

        private final boolean valueDefault;

        private final boolean valueEnforced;

        private final boolean hasSystem;

        private final boolean enforced;

        /**

         * Constructs an XmlFeature instance.

         * @param name the name of the feature

         * @param nameSP the name of the System Property

         * @param nameOld the name of the corresponding legacy property

         * @param nameOldSP the system property of the legacy property

         * @param value the value of the feature

         * @param hasSystem a flag to indicate whether the feature is supported

         * @param enforced a flag indicating whether the feature is

         * FSP (Feature_Secure_Processing) enforced

         * with a System property

         */

        XmlFeature(String name, String nameSP, String nameOld, String nameOldSP,

                boolean value, boolean valueEnforced, boolean hasSystem, boolean enforced) {

            this.name = name;

            this.nameSP = nameSP;

            this.nameOld = nameOld;

            this.nameOldSP = nameOldSP;

            this.valueDefault = value;

            this.valueEnforced = valueEnforced;

            this.hasSystem = hasSystem;

            this.enforced = enforced;

        }

        /**

         * Checks whether the specified property is equal to the current property.

         * @param propertyName the name of a property

         * @return true if the specified property is the current property, false

         * otherwise

         */

        boolean equalsPropertyName(String propertyName) {

            return name.equals(propertyName) ||

                    (nameOld != null && nameOld.equals(propertyName));

        }

        /**

         * Returns the name of the property.

         *

         * @return the name of the property

         */

        public String apiProperty() {

            return name;

        }

        /**

         * Returns the name of the corresponding System Property.

         *

         * @return the name of the System Property

         */

        String systemProperty() {

            return nameSP;

        }

        /**

         * Returns the name of the legacy System Property.

         *

         * @return the name of the legacy System Property

         */

        String systemPropertyOld() {

            return nameOldSP;

        }

        /**

         * Returns the default value of the property.

         * @return the default value of the property

         */

        public boolean defaultValue() {

            return valueDefault;

        }

        /**

         * Returns the FSP-enforced value.

         * @return the FSP-enforced value

         */

        public boolean enforcedValue() {

            return valueEnforced;

        }

        /**

         * Checks whether System property is supported for the feature.

         * @return true it is supported, false otherwise

         */

        boolean hasSystemProperty() {

            return hasSystem;

        }

        /**

         * Checks whether the property is enforced by FSP

         * @return true it is, false otherwise

         */

        boolean enforced() {

            return enforced;

        }

    }

    /**

     * States of the settings of a property, in the order: default value, value

     * set by FEATURE_SECURE_PROCESSING, jaxp.properties file, jaxp system

     * properties, and jaxp api properties

     */

    public static enum State {

        //this order reflects the overriding order

        DEFAULT("default"), FSP("FEATURE_SECURE_PROCESSING"),

        JAXPDOTPROPERTIES("jaxp.properties"), SYSTEMPROPERTY("system property"),

        APIPROPERTY("property");

        final String literal;

        State(String literal) {

            this.literal = literal;

        }

        String literal() {

            return literal;

        }

    }

    /**

     * Values of the features

     */

    private final boolean[] featureValues;

    /**

     * States of the settings for each property

     */

    private final State[] states;

    /**

     * Flag indicating if secure processing is set

     */

    boolean secureProcessing;

    /**

     * Instantiate JdkXmlFeatures and initialize the fields

     * @param secureProcessing

     */

    public JdkXmlFeatures(boolean secureProcessing) {

        featureValues = new boolean[XmlFeature.values().length];

        states = new State[XmlFeature.values().length];

        this.secureProcessing = secureProcessing;

        for (XmlFeature f : XmlFeature.values()) {

            if (secureProcessing && f.enforced()) {

                featureValues[f.ordinal()] = f.enforcedValue();

                states[f.ordinal()] = State.FSP;

            } else {

                featureValues[f.ordinal()] = f.defaultValue();

                states[f.ordinal()] = State.DEFAULT;

            }

        }

        //read system properties or jaxp.properties

        readSystemProperties();

    }

    /**

     * Updates the JdkXmlFeatures instance by reading the system properties again.

     * This will become necessary in case the system properties are set after

     * the instance has been created.

     */

    public void update() {

        readSystemProperties();

    }

    /**

     * Set feature by property name and state

     * @param propertyName property name

     * @param state the state of the property

     * @param value the value of the property

     * @return true if the property is managed by the JdkXmlFeatures instance;

     *         false otherwise.

     */

    public boolean setFeature(String propertyName, State state, Object value) {

        int index = getIndex(propertyName);

        if (index > -1) {

            setFeature(index, state, value);

            return true;

        }

        return false;

    }

    /**

     * Set the value for a specific feature.

     *

     * @param feature the feature

     * @param state the state of the property

     * @param value the value of the property

     */

    public void setFeature(XmlFeature feature, State state, boolean value) {

        setFeature(feature.ordinal(), state, value);

    }

    /**

     * Return the value of the specified property

     *

     * @param feature the property

     * @return the value of the property

     */

    public boolean getFeature(XmlFeature feature) {

        return featureValues[feature.ordinal()];

    }

    /**

     * Return the value of a feature by its index (the Feature's ordinal)

     * @param index the index of a feature

     * @return value of a feature

     */

    public boolean getFeature(int index) {

        return featureValues[index];

    }

    /**

     * Set the value of a property by its index

     *

     * @param index the index of the property

     * @param state the state of the property

     * @param value the value of the property

     */

    public void setFeature(int index, State state, Object value) {

        boolean temp;

        if (Boolean.class.isAssignableFrom(value.getClass())) {

            temp = (Boolean)value;

        } else {

            temp = Boolean.parseBoolean((String) value);

        }

        setFeature(index, state, temp);

    }

    /**

     * Set the value of a property by its index

     *

     * @param index the index of the property

     * @param state the state of the property

     * @param value the value of the property

     */

    public void setFeature(int index, State state, boolean value) {

        //only update if it shall override

        if (state.compareTo(states[index]) >= 0) {

            featureValues[index] = value;

            states[index] = state;

        }

    }

    /**

     * Get the index by property name

     *

     * @param propertyName property name

     * @return the index of the property if found; return -1 if not

     */

    public int getIndex(String propertyName) {

        for (XmlFeature feature : XmlFeature.values()) {

            if (feature.equalsPropertyName(propertyName)) {

                //internally, ordinal is used as index

                return feature.ordinal();

            }

        }

        return -1;

    }

    /**

     * Read from system properties, or those in jaxp.properties

     */

    private void readSystemProperties() {

        for (XmlFeature feature : XmlFeature.values()) {

            if (!getSystemProperty(feature, feature.systemProperty())) {

                //if system property is not found, try the older form if any

                String oldName = feature.systemPropertyOld();

                if (oldName != null) {

                    getSystemProperty(feature, oldName);

                }

            }

        }

    }

    /**

     * Read from system properties, or those in jaxp.properties

     *

     * @param property the type of the property

     * @param sysPropertyName the name of system property

     * @return true if the system property is found, false otherwise

     */

    private boolean getSystemProperty(XmlFeature feature, String sysPropertyName) {

        try {

            String value = SecuritySupport.getSystemProperty(sysPropertyName);

            if (value != null && !value.isEmpty()) {

                setFeature(feature, State.SYSTEMPROPERTY, Boolean.parseBoolean(value));

                return true;

            }

            value = SecuritySupport.readJAXPProperty(sysPropertyName);

            if (value != null && !value.isEmpty()) {

                setFeature(feature, State.JAXPDOTPROPERTIES, Boolean.parseBoolean(value));

                return true;

            }

        } catch (NumberFormatException e) {

            //invalid setting

            throw new NumberFormatException("Invalid setting for system property: " + feature.systemProperty());

        }

        return false;

    }

}