#!/usr/bin/env python

# Copyright 2017-present Open Networking Foundation
#
# 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.

from __future__ import absolute_import, print_function
import sys
import os
from io import open


COPYRIGHTS = {
    "slash": """/*
 * Copyright 2017-present Open Networking Foundation

 * 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.
 */""",
    "hash": """# Copyright 2017-present Open Networking Foundation
#
# 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.""",
    "html": """<!--
Copyright 2017-present Open Networking Foundation

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.
-->""",
    "jinja": """{#
Copyright 2017-present Open Networking Foundation

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.
#}""",
    "ini": """;Copyright 2017-present Open Networking Foundation
;
;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.""",
}

EXT_MAPPING = {
    ".js": COPYRIGHTS["slash"],
    ".ts": COPYRIGHTS["slash"],
    ".scss": COPYRIGHTS["slash"],
    ".css": COPYRIGHTS["slash"],
    ".gradle": COPYRIGHTS["slash"],
    ".go": COPYRIGHTS["slash"],
    ".c": COPYRIGHTS["slash"],
    ".h": COPYRIGHTS["slash"],

    "docker": COPYRIGHTS["hash"],
    ".py": COPYRIGHTS["hash"],
    ".model": COPYRIGHTS["hash"],  # attic files
    ".sh": COPYRIGHTS["hash"],
    ".yaml": COPYRIGHTS["hash"],
    ".yml": COPYRIGHTS["hash"],
    ".m4": COPYRIGHTS["hash"],
    ".sql": COPYRIGHTS["hash"],

    ".html": COPYRIGHTS["html"],
    ".xml": COPYRIGHTS["html"],
    ".j2": COPYRIGHTS["jinja"],
    ".ini": COPYRIGHTS["ini"],
}


def get_copyright(file):
    name, ext = os.path.splitext(file)

    if "Dockerfile" in name:
        return EXT_MAPPING["docker"]
    try:
        return EXT_MAPPING[ext]
    except KeyError:
        print("Missing copyright for file of type: %s" % ext)
        return None


def add_copyright(file):
    with open(file, 'r') as original:
        data = original.read()
    if "Licensed under the Apache License, Version 2.0" not in data:
        print("Adding copyright to: %s" % file)

        # don't push special first lines below copyright
        specialline = ""
        if data and "#!" in data.splitlines()[0]:
            print("Has Shebang: %s" % data.splitlines()[0])
            (specialline, data) = data.split("\n", 1)
            specialline += "\n"

        elif data and "---" in data.splitlines()[0]:
            print("Has YAML start of document: %s" % data.splitlines()[0])
            (specialline, data) = data.split("\n", 1)
            specialline += "\n"

        copy = get_copyright(file)
        if copy:
            with open(file, 'w') as modified:
                modified.write(specialline + copy + "\n" + data)
    return


def get_files_ignore_by_git(root):
    # NOTE this is not perfect, some file will still be copyrighted, but we
    # save some time
    if root == ".gitignore":
        gitignore = root
    else:
        gitignore = os.path.join(root, ".gitignore")

    exclusion_list = []
    if os.path.exists(gitignore):
        for line in open(gitignore).readlines():
            if "#" not in line:
                line = line.strip()
                if line.endswith("/"):
                    line = line.replace("/", "")
                exclusion_list.append(line)
    return exclusion_list


def should_skip(entry):

    # do not skip directories
    if os.path.isdir(entry):
        return False

    if "LICENSE.txt" in entry \
            or ".git" in entry \
            or ".idea" in entry:
        return True

    name, ext = os.path.splitext(entry)
    if not ext or ext == "" \
            or ext == ".pyc" \
            or ext == ".txt" \
            or ext == ".in" \
            or ext == ".crt" \
            or ext == ".unused" \
            or ext == ".list" \
            or ext == ".README" \
            or ext == ".json" \
            or ext == ".log" \
            or ext == ".asc" \
            or ext == ".dot" \
            or ext == ".do" \
            or ext == ".template" \
            or ext == ".svg" \
            or ext == ".ttf" \
            or ext == ".woff" \
            or ext == ".woof2" \
            or ext == ".eot" \
            or ext == ".md" \
            or ext == ".png" \
            or ext == ".pdf" \
            or ext == ".PNG" \
            or ext == ".jpg" \
            or ext == ".gif" \
            or ext == ".ico" \
            or ext == ".conf"\
            or ext == ".key" \
            or ext == ".proto" \
            or ext == ".xproto" \
            or ext == ".xtarget" \
            or ext == ".otf" \
            or ext == ".desc":
        return True
    return False


def recursive_iterate_dirs(source, apply_copyright=True):
    # print "Iterating on: %s" % source
    # skipping files in the gitignore
    gitignored = get_files_ignore_by_git(source)
    entries = []
    for entry in os.listdir(source):

        if entry in gitignored:
            # print "Skipping because gitignored: %s" % entry
            continue

        entry = os.path.join(source, entry)
        if should_skip(entry):
            # print "Skipping: %s" % entry
            continue

        if os.path.isdir(entry):
            entries.append(recursive_iterate_dirs(entry, apply_copyright))
        elif os.path.isfile(entry):
            entries.append(entry)
            if apply_copyright is True:
                add_copyright(entry)
    return entries


def flatten(aList):
    t = []
    for i in aList:
        if not isinstance(i, list):
            t.append(i)
        else:
            t.extend(flatten(i))
    return t


def list_file_types(source):
    file_types = []
    files = flatten(recursive_iterate_dirs(source, apply_copyright=False))
    for entry in files:
        name, ext = os.path.splitext(entry)
        if ext not in file_types:
            file_types.append(ext)
    print(file_types)


def main():
    if len(sys.argv) < 2:
        raise Exception("You must provide a path to the source folder"
                        "as arguments to the script")
    source_root = os.path.abspath(os.path.join(os.getcwd(), sys.argv[1]))
    if not os.path.exists(source_root):
        raise Exception("You must provide an existing the source folder")
    if len(sys.argv) == 3:
        list_file_types(source_root)
    else:
        recursive_iterate_dirs(source_root)


if __name__ == "__main__":
    main()