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

#

# 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 os

import tempfile

class PrettyPatch(object):

    # FIXME: PrettyPatch should not require checkout_root.

    def __init__(self, executive, checkout_root):

        self._executive = executive

        self._checkout_root = checkout_root

    def pretty_diff_file(self, diff):

        # Diffs can contain multiple text files of different encodings

        # so we always deal with them as byte arrays, not unicode strings.

        assert(isinstance(diff, str))

        pretty_diff = self.pretty_diff(diff)

        diff_file = tempfile.NamedTemporaryFile(suffix=".html")

        diff_file.write(pretty_diff)

        diff_file.flush()

        return diff_file

    def pretty_diff(self, diff):

        # pretify.rb will hang forever if given no input.

        # Avoid the hang by returning an empty string.

        if not diff:

            return ""

        pretty_patch_path = os.path.join(self._checkout_root,

                                         "BugsSite", "PrettyPatch")

        prettify_path = os.path.join(pretty_patch_path, "prettify.rb")

        args = [

            "ruby",

            "-I",

            pretty_patch_path,

            prettify_path,

        ]

        # PrettyPatch does not modify the encoding of the diff output

        # so we can't expect it to be utf-8.

        return self._executive.run_command(args, input=diff, decode_output=False)