de.flapdoodle.java2pandoc.parser.BlockToTypedBlockConverter.java Source code

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Here is the source code for de.flapdoodle.java2pandoc.parser.BlockToTypedBlockConverter.java

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/**
 * Copyright (C) 2013
 *   Michael Mosmann <michael@mosmann.de>
 *
 * with contributions from
 *    -
 *
 * Licensed 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 de.flapdoodle.java2pandoc.parser;

import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.annotation.Nonnull;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Optional;
import com.google.common.collect.Lists;
import com.google.common.collect.Sets;

import de.flapdoodle.java2pandoc.block.Block;
import de.flapdoodle.java2pandoc.block.TypedBlock;

public class BlockToTypedBlockConverter implements IBlockToTypedBlockConverter {

    static Pattern LINE_COMMENT_PATTERN = Pattern.compile("(^\\s*//)");
    static Pattern BLOCK_COMMENT_PATTERN = Pattern.compile("(^\\s*\\*\\s)");

    @Override
    public TypedBlock convert(Block block) {
        return guessTypedBlock(block);
    }

    @Nonnull
    @VisibleForTesting
    protected static TypedBlock guessTypedBlock(Block block) {
        Optional<Block> unpackedComment = unpackComment(block);
        if (unpackedComment.isPresent()) {
            return new TypedBlock(TypedBlock.Type.Text, unpackedComment.get());
        }
        return new TypedBlock(TypedBlock.Type.Code, block);
    }

    @Nonnull
    @VisibleForTesting
    protected static Optional<Block> unpackComment(Block block) {
        Optional<Block> blockWithLineCommentStripped = removePattern(block, LINE_COMMENT_PATTERN);
        if (blockWithLineCommentStripped.isPresent()) {
            return blockWithLineCommentStripped;
        }
        return removePattern(block, BLOCK_COMMENT_PATTERN);
    }

    @Nonnull
    @VisibleForTesting
    protected static Optional<Block> removePattern(Block block, Pattern pattern) {
        List<String> processedLines = Lists.newArrayList();
        List<String> removedParts = Lists.newArrayList();

        for (String line : block.lines()) {
            Matcher matcher = pattern.matcher(line);
            if (matcher.find()) {
                removedParts.add(line.substring(0, matcher.end()));
                processedLines.add(line.substring(matcher.end()));
            } else {
                return Optional.absent();
            }
        }
        if (processedLines.size() == block.lines().size() && (sameParts(removedParts))) {
            return Optional.of(new Block(processedLines));
        }
        return Optional.absent();
    }

    private static boolean sameParts(List<String> removedParts) {
        return Sets.newHashSet(removedParts).size() == 1;
    }
}