* Copyright (c) 2005-2011 by Appcelerator, Inc. All Rights Reserved.

* Licensed under the terms of the Eclipse Public License (EPL).

* Please see the license.txt included with this distribution for details.

* Any modifications to this file must keep this entire header intact.

*/

* Author: atotic

* Created: July 10, 2003

*/

* Rule-based partition scanner

*

* Simple, fast parsing of the document into partitions.<p>

* This is like a rough 1st pass at parsing. We only parse

* out for comments, single-line strings, and multiline strings<p>

* The results are parsed again inside {@link org.python.pydev.editor.PyEditConfiguration#getPresentationReconciler}

* and colored there.<p>

*

* "An IPartitionTokenScanner can also start in the middle of a partition,

* if it knows the type of the partition."

*/

    public PyPartitionScanner() {

        super();

        List<IPredicateRule> rules = new ArrayList<IPredicateRule>();

        addMultilineStringRule(rules);

        addSinglelineStringRule(rules);

        addReprRule(rules);

        addCommentRule(rules);

        setPredicateRules(rules.toArray(new IPredicateRule[0]));

    }

    private void addReprRule(List<IPredicateRule> rules) {

        rules.add(new SingleLineRule("`", "`", new Token(IPythonPartitions.PY_BACKQUOTES)));

    }

    private void addSinglelineStringRule(List<IPredicateRule> rules) {

        //        IToken singleLineString = new Token(PY_SINGLELINE_STRING);

        //        rules.add(new SingleLineRule("\"", "\"", singleLineString, '\\'));

        //        rules.add(new SingleLineRule("'", "'", singleLineString, '\\')); -- changed to the construct below because we need to continue on escape

        IToken singleLineString1 = new Token(IPythonPartitions.PY_SINGLELINE_STRING1);

        IToken singleLineString2 = new Token(IPythonPartitions.PY_SINGLELINE_STRING2);

        // deal with "" and '' strings

        boolean breaksOnEOL = true;

        boolean breaksOnEOF = false;

        boolean escapeContinuesLine = true;

        rules.add(new PatternRule("'", "'", singleLineString1, '\\', breaksOnEOL, breaksOnEOF, escapeContinuesLine));

        rules.add(new PatternRule("\"", "\"", singleLineString2, '\\', breaksOnEOL, breaksOnEOF, escapeContinuesLine));

    }

    private void addMultilineStringRule(List<IPredicateRule> rules) {

        IToken multiLineString1 = new Token(IPythonPartitions.PY_MULTILINE_STRING1);

        IToken multiLineString2 = new Token(IPythonPartitions.PY_MULTILINE_STRING2);

        // deal with ''' and """ strings

        boolean breaksOnEOF = true;

        //If we don't add breaksOnEOF = true it won't properly recognize the rule while typing

        //in the following case:

        ///'''<new line>

        //text

        //''' <-- it's already lost at this point and the 'text' will not be in a multiline string partition.

        rules.add(new MultiLineRule("'''", "'''", multiLineString1, '\\', breaksOnEOF));

        rules.add(new MultiLineRule("\"\"\"", "\"\"\"", multiLineString2, '\\', breaksOnEOF));

        //there is a bug in this construct: When parsing a simple document such as:

        //

        //"""ttt"""

        //print 'a'

        //

        //if lines are feed after 'ttt', it ends up considering the whole document as a multiline string.

        //the bug is reported at: http://sourceforge.net/tracker/index.php?func=detail&aid=1402165&group_id=85796&atid=577329

        //

        //some regards on the bug:

        //- it does not happen if the multiline has ''' instead of """

        //- also, if we first add the """ rule and after the ''' rule, the bug happens with ''' and not """

        //- if the user later changes the first line of that multiline or a line above it, it ends up parsing correctly again

        //- if we let just one of the constructs, no problem happens

        //

        //I also tried creating a new token for it, but it had problems too (not the same ones, but had other problems).

    }

    private void addCommentRule(List<IPredicateRule> rules) {

        IToken comment = new Token(IPythonPartitions.PY_COMMENT);

        rules.add(new EndOfLineRule("#", comment));

    }

    /**

     * @return all types recognized by this scanner (used by doc partitioner)

     */

    static public String[] getTypes() {

        return IPythonPartitions.types;

    }

    /**

     * Checks if the partitioner is correctly set in the document.

     * @return the partitioner that is set in the document

     */

    public static IDocumentPartitioner checkPartitionScanner(IDocument document) {

        if (document == null) {

            return null;

        }

        IDocumentExtension3 docExtension = (IDocumentExtension3) document;

        IDocumentPartitioner partitioner = docExtension.getDocumentPartitioner(IPythonPartitions.PYTHON_PARTITION_TYPE);

        if (partitioner == null) {

            addPartitionScanner(document);

            //get it again for the next check

            partitioner = docExtension.getDocumentPartitioner(IPythonPartitions.PYTHON_PARTITION_TYPE);

        }

        if (!(partitioner instanceof PyPartitioner)) {

            Log.log("Partitioner should be subclass of PyPartitioner. It is " + partitioner.getClass());

        }

        return partitioner;

    }

    /**

     * @see http://help.eclipse.org/help31/index.jsp?topic=/org.eclipse.platform.doc.isv/guide/editors_documents.htm

     * @see http://jroller.com/page/bobfoster -  Saturday July 16, 2005

     * @param document the document where we want to add the partitioner

     * @return the added document partitioner (or null)

     */

    public static IDocumentPartitioner addPartitionScanner(IDocument document) {

        if (document != null) {

            IDocumentExtension3 docExtension = (IDocumentExtension3) document;

            IDocumentPartitioner curr = docExtension.getDocumentPartitioner(IPythonPartitions.PYTHON_PARTITION_TYPE);

            if (curr == null) {

                //set the new one

                FastPartitioner partitioner = createPyPartitioner();

                partitioner.connect(document);

                docExtension.setDocumentPartitioner(IPythonPartitions.PYTHON_PARTITION_TYPE, partitioner);

                return partitioner;

            } else {

                return curr;

            }

        }

        return null;

    }

    public static PyPartitioner createPyPartitioner() {

        return new PyPartitioner(new PyPartitionScanner(), getTypes());

    }

}