# Copyright (C) 2013 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.path
import shlex
import shutil
import optparse

from in_file import InFile


class Writer(object):
    # Subclasses should override.
    class_name = None
    defaults = None
    valid_values = None
    default_parameters = None

    def __init__(self, in_files, enabled_conditions):
        if isinstance(in_files, basestring):
            in_files = [in_files]
        self.in_file = InFile.load_from_files(in_files, self.defaults, self.valid_values, self.default_parameters)
        self._enabled_conditions = enabled_conditions
        self._outputs = {}  # file_name -> generator

    def wrap_with_condition(self, string, condition):
        if not condition:
            return string
        return "#if ENABLE(%(condition)s)\n%(string)s\n#endif" % { 'condition' : condition, 'string' : string }

    def _forcibly_create_text_file_at_path_with_contents(self, file_path, contents):
        # FIXME: This method can be made less force-full anytime after 6/1/2013.
        # A gyp error was briefly checked into the tree, causing
        # a directory to have been generated in place of one of
        # our output files.  Clean up after that error so that
        # all users don't need to clobber their output directories.
        shutil.rmtree(file_path, ignore_errors=True)
        # The build system should ensure our output directory exists, but just in case.
        directory = os.path.dirname(file_path)
        if not os.path.exists(directory):
            os.makedirs(directory)

        with open(file_path, "w") as file_to_write:
            file_to_write.write(contents)

    def _write_file(self, output_dir, contents, file_name):
        path = os.path.join(output_dir, file_name)
        self._forcibly_create_text_file_at_path_with_contents(path, contents)

    def write_files(self, output_dir):
        for file_name, generator in self._outputs.items():
            self._write_file(output_dir, generator(), file_name)


class Maker(object):
    def __init__(self, writer_class):
        self._writer_class = writer_class

    def _enabled_conditions_from_defines(self, defines_arg_string):
        if not defines_arg_string:
            return []

        defines_strings = shlex.split(defines_arg_string)

        # We only care about feature defines.
        enable_prefix = 'ENABLE_'

        enabled_conditions = []
        for define_string in defines_strings:
            split_define = define_string.split('=')
            if split_define[1] != '1':
                continue
            define = split_define[0]
            if not define.startswith(enable_prefix):
                continue
            enabled_conditions.append(define[len(enable_prefix):])
        return enabled_conditions

    def main(self, argv):
        script_name = os.path.basename(argv[0])
        args = argv[1:]
        if len(args) < 1:
            print "USAGE: %i INPUT_FILES" % script_name
            exit(1)

        parser = optparse.OptionParser()
        parser.add_option("--defines")
        parser.add_option("--output_dir", default=os.getcwd())
        (options, args) = parser.parse_args()

        enabled_conditions = self._enabled_conditions_from_defines(options.defines)

        writer = self._writer_class(args, enabled_conditions)
        writer.write_files(options.output_dir)