src/main/java/org/apache/sling/query/impl/selector/parser/State.java

/*-
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.sling.query.impl.selector.parser;

import org.apache.commons.lang.ArrayUtils;

public enum State {
    START {
        @Override
        public void process(ParserContext context, char c) {
            if (c == '/') {
                context.setState(State.TYPE_WITH_SLASHES);
                context.append(c);
            } else if (c == '[') {
                context.setState(State.ATTRIBUTE_KEY);
            } else if (c == ':') {
                context.setState(State.MODIFIER);
            } else if (c == '>' || c == '+' || c == '~') {
                context.setHierarchyOperator(c);
            } else if (c == '#') {
                context.setType();
                context.setState(NAME);
            } else if (c != ' ') {
                context.setState(State.TYPE);
                context.append(c);
            }
        }
    },
    IDLE {
        @Override
        public void process(ParserContext context, char c) {
            if (c == '[') {
                context.setState(State.ATTRIBUTE_KEY);
            } else if (c == ':') {
                context.setState(State.MODIFIER);
            } else if (c == ' ') {
                context.finishSelectorSegment();
                context.setState(START);
            } else if (c == ',' || c == 0) {
                context.finishSelectorSegment();
                context.finishSelector();
                context.setState(START);
            }
        }
    },
    TYPE {
        @Override
        public void process(ParserContext context, char c) {
            if (c == '/') {
                context.setState(State.TYPE_WITH_SLASHES);
                context.append(c);
            } else if (c == '[') {
                context.setState(State.ATTRIBUTE_KEY);
                context.setType();
            } else if (c == ':') {
                context.setState(State.TYPE_WITH_SLASHES);
                context.append(c);
            } else if (c == '#') {
                context.setType();
                context.setState(NAME);
            } else if (c == ' ') {
                context.setType();
                context.finishSelectorSegment();
                context.setState(START);
            } else if (c == ',' || c == 0) {
                context.setType();
                context.finishSelectorSegment();
                context.finishSelector();
                context.setState(START);
            } else {
                context.append(c);
            }
        }
    },
    TYPE_WITH_SLASHES {
        @Override
        public void process(ParserContext context, char c) {
            if (c == '[') {
                context.setState(State.ATTRIBUTE_KEY);
                context.setType();
            } else if (c == ':') {
                context.setState(State.MODIFIER);
                context.setType();
            } else if (c == '#') {
                context.setType();
                context.setState(NAME);
            } else if (c == ' ') {
                context.setType();
                context.finishSelectorSegment();
                context.setState(START);
            } else if (c == ',' || c == 0) {
                context.setType();
                context.finishSelectorSegment();
                context.finishSelector();
                context.setState(START);
            } else {
                context.append(c);
            }
        }
    },
    NAME {
        @Override
        public void process(ParserContext context, char c) {
            if (c == '[') {
                context.setName();
                context.setState(State.ATTRIBUTE_KEY);
            } else if (c == ':') {
                context.setName();
                context.setState(State.MODIFIER);
            } else if (c == ' ') {
                context.setName();
                context.finishSelectorSegment();
                context.setState(START);
            } else if (c == ',' || c == 0) {
                context.setName();
                context.finishSelectorSegment();
                context.finishSelector();
                context.setState(START);
            } else if (c == '\'') {
                context.setState(State.ESCAPED_NAME);
            } else {
                context.append(c);
            }
        }
    },
    ESCAPED_NAME {
        @Override
        public void process(ParserContext context, char c) {
            if (c == '\'') {
                context.setName();
                context.setState(IDLE);
            } else {
                context.append(c);
            }
        }
    },
    ATTRIBUTE_KEY {
        @Override
        public void process(ParserContext context, char c) {
            if (c == ']') {
                context.setAttributeKey();
                context.addAttribute();
                context.setState(State.IDLE);
            } else if (ArrayUtils.contains(OPERATORS, c)) {
                context.setAttributeKey();
                context.setState(State.ATTRIBUTE_OPERATOR);
                context.append(c);
            } else {
                context.append(c);
            }
        }
    },
    ATTRIBUTE_OPERATOR {
        @Override
        public void process(ParserContext context, char c) {
            if (!ArrayUtils.contains(OPERATORS, c)) {
                context.setAttributeOperator();
                context.append(c);
                context.setState(ATTRIBUTE_VALUE);
            } else {
                context.append(c);
            }
        }
    },
    ATTRIBUTE_VALUE {
        @Override
        public void process(ParserContext context, char c) {
            if (c == ']') {
                context.setState(State.IDLE);
                context.setAttributeValue();
                context.addAttribute();
            } else {
                context.append(c);
            }
        }
    },
    MODIFIER {
        @Override
        public void process(ParserContext context, char c) {
            if (c == ':') {
                context.addModifier();
            } else if (c == '(') {
                context.setModifierName();
                context.setState(State.MODIFIER_ARGUMENT);
                context.increaseParentheses();
            } else if (c == ' ') {
                context.addModifier();
                context.finishSelectorSegment();
                context.setState(START);
            } else if (c == ',' || c == 0) {
                context.addModifier();
                context.finishSelectorSegment();
                context.finishSelector();
                context.setState(START);
            } else {
                context.append(c);
            }
        }
    },
    MODIFIER_ARGUMENT {
        @Override
        public void process(ParserContext context, char c) {
            if (c == ')') {
                if (context.decreaseParentheses() == 0) {
                    context.addModifier();
                    context.setState(IDLE);
                } else {
                    context.append(c);
                }
            } else if (c == '(') {
                context.increaseParentheses();
                context.append(c);
            } else {
                context.append(c);
            }
        }
    };
    public abstract void process(ParserContext context, char c);

    private static final char[] OPERATORS = "*~$!^=".toCharArray();
}