#!/usr/bin/env python
# -*- python -*-
# Copyright The IETF Trust 2019, All Rights Reserved
"""
NAME
	$program - Check for current copyright notice in given files

SYNOPSIS
	$program [OPTIONS] ARGS

DESCRIPTION
	Given a list of files or filename wildcard patterns, check all for
	an IETF Trust copyright notice with the current year.

%(options)s

FILES

AUTHOR
	Written by Henrik Levkowetz, <henrik@tools.ietf.org>

COPYRIGHT
	Copyright 2019 the IETF Trust

	This program is free software; you can redistribute it and/or modify
	it under the terms of the Simplified BSD license as published by the
        Open Source Initiative at http://opensource.org/licenses/BSD-2-Clause.

"""
from __future__ import print_function

import os
import sys
import time

path = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
if not path in sys.path:
    sys.path.insert(0, path)

import getopt
import re
import pytz
import tzparse
import debug

version = "0.10"
program = os.path.basename(sys.argv[0])
progdir = os.path.dirname(sys.argv[0])

# ----------------------------------------------------------------------
# Parse options

options = ""
for line in re.findall("\n +(if|elif) +opt in \[(.+)\]:\s+#(.+)\n", open(sys.argv[0]).read()):
    if not options:
        options += "OPTIONS\n"
    options += "        %-16s %s\n" % (line[1].replace('"', ''), line[2])
options = options.strip()

# with ' < 1:' on the next line, this is a no-op:
if len(sys.argv) < 1:
    print(__doc__ % locals())
    sys.exit(1)

try:
    opts, files = getopt.gnu_getopt(sys.argv[1:], "hvV", ["help", "version", "verbose",])
except Exception, e:
    print( "%s: %s" % (program, e))
    sys.exit(1)

# ----------------------------------------------------------------------
# Handle options

# set default values, if any
opt_verbose = 0

# handle individual options
for opt, value in opts:
    if   opt in ["-h", "--help"]: # Output this help, then exit
        print( __doc__ % locals() )
        sys.exit(1)
    elif opt in ["-V", "--version"]: # Output version information, then exit
        print( program, version )
        sys.exit(0)
    elif opt in ["-v", "--verbose"]: # Output version information, then exit
        opt_verbose += 1

# ----------------------------------------------------------------------
def say(s):
    sys.stderr.write("%s\n" % (s))

# ----------------------------------------------------------------------
def note(s):
    if opt_verbose:
        sys.stderr.write("%s\n" % (s))

# ----------------------------------------------------------------------
def die(s, error=1):
    sys.stderr.write("\n%s: Error: %s\n\n" % (program, s))
    sys.exit(error)

# ----------------------------------------------------------------------

def pipe(cmd, inp=None):
    import shlex
    from subprocess import Popen, PIPE
    args = shlex.split(cmd)
    bufsize = 4096
    stdin = PIPE if inp else None
    pipe = Popen(args, stdin=stdin, stdout=PIPE, stderr=PIPE, bufsize=bufsize)
    out, err = pipe.communicate(inp)
    code = pipe.returncode
    if code != 0:
        raise OSError(err)
    return out

# ----------------------------------------------------------------------
def split_loginfo(line):
    try:
        parts = line.split()
        rev  = parts[0][1:]
        who  = parts[2]
        date = parts[4]
        time = parts[5]
        tz   = parts[6]
        when = tzparse.tzparse(" ".join(parts[4:7]), "%Y-%m-%d %H:%M:%S %Z")
        when = when.astimezone(pytz.utc)
    except ValueError as e:
        sys.stderr.write("Bad log line format: %s\n  %s\n" % (line, e))

    return rev, who, when

# ----------------------------------------------------------------------
def get_first_commit(path):
    note("Getting first commit for '%s'" % path)
    cmd = 'svn log %s' % path
    if opt_verbose > 1:
        note("Running '%s' ..." % cmd)
    commit_log = pipe(cmd)
    commit_log = commit_log.splitlines()
    commit_log.reverse()
    for line in commit_log:
        if re.search(loginfo_format, line):
            rev, who, when = split_loginfo(line)
            break
        else:
            pass
    return { path: { 'rev': rev, 'who': who, 'date': when.strftime('%Y-%m-%d %H:%M:%S'), }, }


# ----------------------------------------------------------------------
# The program itself    

import os
import json

cwd = os.getcwd()

if cwd.split(os.path.sep)[-1] != 'trunk':
    die("Expected to run this operation in trunk, but the current\ndirectory is '%s'" % cwd)

# Get current initinfo from cache and svn
cachefn = os.path.join(os.environ.get('HOME', '.'), '.initinfo')

if os.path.exists(cachefn):
    note("Reading initinfo cache file %s" % cachefn)
    with open(cachefn, "r") as file:
        cache = json.load(file)
else:
    sys.stderr.write("No  initinfo cache file found -- will have to extract all information from SVN.\n"+
        "This may take some time.\n\n")
    cache = {}
initinfo = cache

merged_revs = {}
write_cache = False
loginfo_format = r'^r[0-9]+ \| [^@]+@[^@]+ \| \d\d\d\d-\d\d-\d\d '

year = time.strftime('%Y')
for path in files:
    note("Checking path %s" % path)
    if not path in initinfo:
        initinfo.update(get_first_commit(path))
        write_cache = True
    date = initinfo[path]['date']
    init = date[:4]
    copyright = "(?i)Copyright The IETF Trust (%s-)?%s, All Rights Reserved" % (init, year)
    with open(path) as file:
        chunk = file.read(4000)
        if os.path.basename(path) == '__init__.py' and len(chunk)==0:
            continue
        if not re.search(copyright, chunk):
            sys.stdout.write("%s(1): Error: Missing or bad copyright.  " % path)
            if year == init:
                print("  Expected: Copyright The IETF Trust %s, All Rights Reserved" % year)
            else:
                print("  Expected: Copyright The IETF Trust %s-%s, All Rights Reserved" % (init, year))

if write_cache:
    cache = initinfo
    with open(cachefn, "w") as file:
        json.dump(cache, file, indent=2, sort_keys=True)