'''
(*)~---------------------------------------------------------------------------
Pupil - eye tracking platform
Copyright (C) 2012-2017  Pupil Labs

Distributed under the terms of the GNU
Lesser General Public License (LGPL v3.0).
See COPYING and COPYING.LESSER for license details.
---------------------------------------------------------------------------~(*)
'''
import fnmatch
import os
import re

license_txt = """\
(*)~---------------------------------------------------------------------------
Pupil - eye tracking platform
Copyright (C) 2012-2017  Pupil Labs

Distributed under the terms of the GNU
Lesser General Public License (LGPL v3.0).
See COPYING and COPYING.LESSER for license details.
---------------------------------------------------------------------------~(*)\
"""


pattern = re.compile('(\'{3}|[/][*])\n\([*]\)~(.+?)~\([*]\)\n(\'{3}|[*][/])', re.DOTALL|re.MULTILINE)

# choose files types to include
# choose directories to exclude from search
includes = ['*.py', '*.c','*.cpp','*.hpp','*.h','*.pxd','*.pyx','*.pxi']
excludes = [ 'recordings*', 'shader.py','singleeyefitter*',
            'vertex_buffer.py', 'gprof2dot.py','git_version.py',
            'transformations.py','libuvcc*', '.gitignore','glfw.py',
            'version_utils.py','update_license_header.py','shared_cpp*']

# transform glob patterns to regular expressions
includes = r'|'.join([fnmatch.translate(x) for x in includes])
excludes = r'|'.join([fnmatch.translate(x) for x in excludes]) or r'$.'

def get_files(start_dir, includes, excludes):
    # use os.walk to recursively dig down into the Pupil directory
    match_files = []
    for root, dirs, files in os.walk(start_dir):
        if not re.search(excludes, root):
            files = [f for f in files if re.search(includes, f) and not re.search(excludes, f)]
            files = [os.path.join(root, f) for f in files]
            match_files += files
        else:
            print("Excluding '%s'"%root)

    return match_files

def write_header(file_name, license_txt):
    # find and replace license header
    # or add new header if not existing
    c_comment = ['/*\n', '\n*/\n']
    py_comment = ["'''\n","\n'''\n"]
    file_type = os.path.splitext(file_name)[-1]

    if file_type in ('.py','.pxd','.pyx','.pxi'):
        license_txt = py_comment[0] + license_txt + py_comment[1]
    elif file_type in ('.c','.cpp','.hpp','.h'):
        license_txt = c_comment[0] + license_txt + c_comment[1]
    else:
        raise Exception("Dont know how to deal with this filetype")

    with file(file_name, 'r') as original:
        data = original.read()

    with file(file_name, 'w') as modified:
        if re.findall(pattern, data):
            # if header already exists, then update, but dont add the last newline.
            modified.write(re.sub(pattern, license_txt[:-1], data))
            modified.close()
        else:
            # else write the license header
            modified.write(license_txt + data)
            modified.close()

if __name__ == '__main__':

    # find out the cwd and change to the top level Pupil folder
    cwd = os.getcwd()
    pupil_dir = cwd

    # Add a license/docstring header to selected files
    match_files = get_files(pupil_dir, includes, excludes)
    print len(match_files)

    for f in match_files:
        write_header(f, license_txt)