# Copyright (C) 2010 Google Inc. All rights reserved.

# Copyright (C) 2010 Chris Jerdonek (chris.jerdonek@gmail.com)

# Copyright (C) 2010 ProFUSION embedded systems

#

# Redistribution and use in source and binary forms, with or without

# modification, are permitted provided that the following conditions are

# met:

#

#     * Redistributions of source code must retain the above copyright

# notice, this list of conditions and the following disclaimer.

#     * Redistributions in binary form must reproduce the above

# copyright notice, this list of conditions and the following disclaimer

# in the documentation and/or other materials provided with the

# distribution.

#     * Neither the name of Google Inc. nor the names of its

# contributors may be used to endorse or promote products derived from

# this software without specific prior written permission.

#

# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

import logging

from webkitpy.common.checkout.diff_parser import DiffParser

_log = logging.getLogger("webkitpy.style.patchreader")

class PatchReader(object):

    """Supports checking style in patches."""

    def __init__(self, text_file_reader):

        """Create a PatchReader instance.

        Args:

          text_file_reader: A TextFileReader instance.

        """

        self._text_file_reader = text_file_reader

    def check(self, patch_string):

        """Check style in the given patch."""

        patch_files = DiffParser(patch_string.splitlines()).files

        # The diff variable is a DiffFile instance.

        for path, diff in patch_files.iteritems():

            line_numbers = set()

            for line in diff.lines:

                # When deleted line is not set, it means that

                # the line is newly added (or modified).

                if not line[0]:

                    line_numbers.add(line[1])

            _log.debug('Found %s new or modified lines in: %s'

                       % (len(line_numbers), path))

            # If line_numbers is empty, the file has no new or

            # modified lines.  In this case, we don't check the file

            # because we'll never output errors for the file.

            # This optimization also prevents the program from exiting

            # due to a deleted file.

            if line_numbers:

                self._text_file_reader.process_file(file_path=path,

                                                    line_numbers=line_numbers)