#!/usr/bin/env python3

############################################################################
#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.  The
# ASF licenses this file to you 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.
#
############################################################################

import json
import sys
import re
import subprocess
import getopt
import termcolor
import os

committers_json = None
non_commiters_json = None
author_mappings_json = None

verbose_level = 0
color = True

def colored(s,c):
    if color:
        return termcolor.colored(s,c)
    else:
        return s

def commit_attributions(c):
    regex = re.compile('(?i)(?:by|from|author|Co-authored-by):? +(.+)')
    return re.findall(regex, c['message']) + re.findall(regex,c['body'])

def get_headers(s):
    return re.findall('(?i)/\*\*\*.+?(?:Copyright).+?\*\*\*+/', s, re.DOTALL)

def get_file(blob):
    try:
        return subprocess.check_output(['git','cat-file','-p',blob], stderr=subprocess.DEVNULL).decode()
    except subprocess.CalledProcessError as err:
        return None

def header_authors(header):
    results = re.findall('[Aa]uthors?: +(.+?) *(?:Redistribution)', header, re.DOTALL)
    results = [re.split('\n[ *]+',result) for result in results]
    results = sum(results,[]) # flatten
    results = [re.sub('[Cc]opyright:?( ?.[Cc].)? *([12][0-9]{3}[,-]? ?)','',result) for result in results]
    results = list(filter(lambda s: s != '', results)) # remove empty strings
    return results

# Search for an author name in Apache's commiters/non-commiters
# database. It will return (apacheID,name) if there's a match or
# None if not. apacheID might be None if there's no Apache ID
# for author

def search_for_cla(name):
    for k,v in committers_json['committers'].items():
        if (v == name):
            return (k,v)

    if name in non_committers_json['non_committers']:
        return (None,name)

    return None

# Returns the same as above, but this takes an author
# (which may include an email include an email used
# to look for alternative author names for this person)

def author_has_cla(author):
    if ('@' in author):
        matches = re.match('^(.+?)(?: +([^ ]+@[^ ]+ *))$', author)
        if (not matches):
            return None # found an '@' but it wasn't an email, so this is most likely not really an author
        name = matches.group(1)
        email = matches.group(2).lstrip('<').rstrip('>')
    else:
        name = author.strip()
        email = None

    vvvprint('name: %s email: %s' % (name,email if email else '?'))

    # first look for name directly

    result = search_for_cla(name)
    if (result):
        return result
    
    # otherwise, get all available alternative names for author
    # and look for each

    if (email and (email in author_mappings_json)):
        result = search_for_cla(author_mappings_json[email])
        if (result):
            return result
            
    # Nothing matched

    return None

def header_copyrights(header):
    results = re.findall(' \* *[Cc]opyright:?(?: ?.[Cc].)? *(?:[12][0-9]{3}[,-]? ?)* *(.+)', header)
    return [re.sub('(. )?[Aa]ll rights reserved.?','',result) for result in results]

def report_cla(author):
    cla = author_has_cla(author)
    if cla:
        (apacheid,name) = cla
        print(colored('✓','green'), end = ' ')
    else:
        apacheid = None
        print(colored('✗','red'), end = ' ')

    if apacheid:
        print('%s (ID: %s)' % (author, apacheid))
    else:
        print(author)

def analyze(j):
    complete_attributions = set()
    complete_authors = set()
    complete_copyrights = set()

    vprint('file has %i commits' % len(j))
    for commit in j:
        authors = set()
       
        vprint(colored('-','yellow'))
        vprint(colored('commit: ', 'green') + commit['commit'])
        vprint(colored('blob: ', 'green') + commit['blob'])
        vprint(colored('date: ','green') + commit['date'])
        vprint(colored('author: ','green') + ('%s <%s>' % (commit['author'], commit['author-email'])))

        attributions = commit_attributions(commit)
        if (len(attributions) > 0):
            vprint(colored('attributions:','green'))
            for attribution in attributions:
                vprint(attribution)

        complete_attributions |= set(attributions)
        complete_authors |= set([commit['author'] + ' ' + commit['author-email']])

        # skip deletion commits 

        vprint(colored('blob:','green'), end = ' ')
        if (commit['blob'] == '0000000000000000000000000000000000000000'):
            vprint('zero (deletion)')
            continue 

        file_contents = get_file(commit['blob'])

        # skip inaccesible blobs (probably lived in a submodule)


        if (not file_contents):
            vprint('inaccessible')
            continue
        else:
            vprint('available')

        headers = get_headers(file_contents)

        vprint(colored('header authors:','green'))
        for header in headers:
            ha = header_authors(header)
            authors |= set(ha)
            vprint(ha)

        complete_authors |= set(authors)

        vprint(colored('header copyrights:','green'))
        copyrights = set()
        for header in headers:
            hc = header_copyrights(header)
            copyrights |= set(hc)
            vprint(hc)
    
        vprint(colored('commit description:','green'))
        vprint(commit['message'])

        if commit['body']:
            vprint(colored('commit msg body:','green'))
            vprint(commit['body'])

        vvprint(colored('headers:','green'))
        for header in headers:
            vvprint(header)

        complete_copyrights |= copyrights

    vprint(colored("----\n",'yellow'))
    
    print(colored("COMPLETE REPORT:",'blue'))
    print(colored("attributions:",'green'))
    if (len(complete_attributions) == 0):
        print("*none detected*")
    else:
        for attribution in complete_attributions:
            report_cla(attribution)

    print(colored("authors:",'green'))
    for author in complete_authors:
        report_cla(author)

    print(colored("copyrights:",'green'))
    print('\n'.join(complete_copyrights))

def print_help():
    print("Usage: check.py [-v] [-n] <JSON file>\n")
    print("  -v\tIncrease verbosity (add up to three times)\n"
          "  -n\tDo not use color for output")

def vprint(*args, **kwargs):
    if (verbose_level > 0):
        print(*args, **kwargs)

def vvprint(*args, **kwargs):
    if (verbose_level > 1):
        print(*args, **kwargs)

def vvvprint(*args, **kwargs):
    if (verbose_level > 2):
        print(*args, **kwargs)

#####

# First try to load the CLAs JSONs:

try:
    with open(os.path.dirname(os.path.abspath(__file__)) + '/icla-info.json','r') as file:
        committers_json = json.load(file)

    with open(os.path.dirname(os.path.abspath(__file__)) + '/icla-info_noid.json','r') as file:
        non_committers_json = json.load(file)
except:
    print('Could not open CLA JSON files, please read README.md for download instructions')
    sys.exit(2)

# Open author mappings JSON

with open(os.path.dirname(os.path.abspath(__file__)) + '/author_mappings.json','r') as file:
    author_mappings_json = json.load(file)

try:
    opts, args = getopt.getopt(sys.argv[1:], "hnv")
except getopt.GetoptError:
    print_help()
    sys.exit(2)
for opt, arg in opts:
    if (opt == "-h"):
        print_help()
        sys.exit()
    elif opt == "-v":
        verbose_level = verbose_level + 1
    elif opt == "-n":
        color = False

if (len(args) != 1):
    print_help()
    sys.exit(2)

f = args[0]

if not f:
    print_help()
    sys.exit(2)

if (f == '-'):
    j = json.load(sys.stdin)
else:
    with open(f, 'r') as file:
       j = json.load(file)

analyze(j)