#!/usr/bin/env python
# Copyright (c) 2009 Tim Freeman
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
#
# (This is the standard MIT License, copied from
# http://www.opensource.org/licenses/mit-license.php on 24 Apr 2007.)
#desc Check that the given files incorporate copies of the LICENSE file.
#desc If -fix is passed, modify files to make them have a license.
# Tested on Linux.  On a Windows or Mac, think more about the \r\n's
# or the \r's at the ends of the lines, and perhaps redo the part
# about preserving the execute bit.
import sys
from os import stat, chmod, rename
from util import read_file
import license_text
from license_text import trim_trailing_spaces

python_comment = "# "

license = license_text.license(lambda x:x)
license = python_comment + license.replace("\n", "\n" + python_comment)
license = trim_trailing_spaces(license)+"\n"

split_license = license.split("\n")
assert "Copyright" in split_license[0]
most_of_license = "\n".join(split_license[1:])
assert "Copyright" not in most_of_license

def has_stale_license(name):
    return not has_license(name) and \
           (most_of_license in trim_trailing_spaces(read_file(name)))

def has_license(name):
    return license in trim_trailing_spaces(read_file(name))

def usage():
    sys.stderr.write("Usage: python license_check.py [-fix] files...")

def check_spelling(name):
    # Avoid saying Turing machine with a little t so we avoid
    # triggering when analyzing our own source.
    if "Turing machine".lower() in read_file(name):
        print "Bad capitalization for \"Turing machine\" in %r" % (name,)

if len(sys.argv) == 0:
    usage()
elif sys.argv[1] == "-fix":
    # -fix will add the license if it's missing,
    # and it will update the copyright data if it has gone stale.
    for name in sys.argv[2:]:
        check_spelling(name)
        if not has_license(name):
           copy_name = name + ".copy"
           first_line = True
           added_license = False
           out = file(copy_name, "w")
           f = file(name)
           if has_stale_license(name):
               print "Found stale copyright in %r" % (name,)
               found_a_line = False
               for line in f:
                   if line.startswith("# Copyright (c) ") and \
                      line.endswith(" Tim Freeman\n"):
                       line = split_license[0] + "\n"
                       found_a_line = True
                   out.write(line)
               if not found_a_line:
                   print "Found no stale copyright in %r" % (name,)
           else:
               # Needs a fresh license.
               for line in f:
                   if (line.startswith("#!") or "-*-" in line) and first_line:
                       # Keep the #! line unchanged if it's the first line
                       # of the file, so executable scripts can still find
                       # their interpreter.
                       pass
                   else:
                       if not added_license:
                           added_license = True
                           out.write(license)
                   out.write(line)
                   first_line = False
           out.close()
           # Preserve the execute bit.
           mode = stat(name).st_mode
           chmod(copy_name, mode)
           rename(copy_name, name)
           if not has_license(name):
               print "Failed to add a license to %r" % (name,)
               print "license is %s" % (license,)
               print "Text from %r is %s" % (name, read_file(name))
           assert has_license(name), "Failed to add a license to %r" % (name,)
else:
    failed = False
    for name in sys.argv[1:]:
        check_spelling(name)
        if not has_license(name):
            if has_stale_license(name):
                print "Stale copyright notice found in %r" % (name,)
            else:
                print "No license found in %r" % (name,)
            failed = True
    if failed:
        # Get Make to stop so I notice the problem.
        sys.exit(1)