# -*- coding: utf-8 -*-

#-------------------------------------------------------------------------
# drawElements Quality Program utilities
# --------------------------------------
#
# Copyright 2015 The Android Open Source Project
#
# 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.
#
#-------------------------------------------------------------------------

import os
import sys
from fnmatch import fnmatch
from optparse import OptionParser

HEADER_PATTERNS = ["*.hpp", "*.h"]
IGNORE_FILES = set(["tcuEAGLView.h", "tcuIOSAppDelegate.h", "tcuIOSViewController.h"])
CHECK_END_COMMENT = True

def getIncludeGuardName (headerFile):
    return '_' + os.path.basename(headerFile).upper().replace('.', '_')

def hasValidIncludeGuard (headerFile):
    includeGuard = getIncludeGuardName(headerFile)
    f = open(headerFile, 'rt')
    isHpp = headerFile[-4:] == ".hpp"

    line0 = f.readline().strip()
    line1 = f.readline().strip()

    if line0 != ("#ifndef %s" % includeGuard):
        return False
    if line1 != ("#define %s" % includeGuard):
        return False

    if CHECK_END_COMMENT:
        lastLine = ""
        expectedComment = ("#endif // %s" if isHpp else "#endif /* %s */") % includeGuard
        for line in f:
            lastLine = line.strip()

        if lastLine != expectedComment:
#            print("'%s' != '%s'" % (lastLine, expectedComment))
            return False

    f.close()
    return True

def fixIncludeGuard (headerFile):
    f = open(headerFile, 'rt')
    lines = []
    isHpp = headerFile[-4:] == ".hpp"
    includeGuard =  getIncludeGuardName(headerFile)

    for line in f:
        lines.append(line)
    f.close()

    # Replace include guards
    lines[0] = "#ifndef %s\n" % includeGuard
    lines[1] = "#define %s\n" % includeGuard

    if CHECK_END_COMMENT:
        lines[len(lines)-1] = ("#endif // %s\n" if isHpp else "#endif /* %s */\n") % includeGuard

    f = open(headerFile, 'wt')
    for line in lines:
        f.write(line)
    f.close()

def isHeader (filename):
    if os.path.basename(filename) in IGNORE_FILES:
        return False

    for pattern in HEADER_PATTERNS:
        if fnmatch(filename, pattern):
            return True
    return False

def getHeaderFileList (path):
    headers = []
    if os.path.isfile(path):
        if isHeader(path):
            headers.append(path)
    else:
        for root, dirs, files in os.walk(path):
            for file in files:
                if isHeader(file):
                    headers.append(os.path.join(root, file))
    return headers

def checkIncludeGuards (files):
    error = False
    for file in files:
        if isHeader(file):
            if not hasValidIncludeGuard(file):
                error = True
                print("File %s contains invalid include guards" % file)
    return not error

if __name__ == "__main__":
    parser = OptionParser()
    parser.add_option("-x", "--fix", action="store_true", dest="fix", default=False, help="attempt to fix include guards (use with caution)")

    (options, args) = parser.parse_args()
    fix = options.fix
    headers = []
    invalidHeaders = []

    for dir in args:
        headers += getHeaderFileList(os.path.normpath(dir))

    print("Checking...")
    for header in headers:
        print("  %s" % header)
        if not hasValidIncludeGuard(header):
            invalidHeaders.append(header)

    print("")
    if len(invalidHeaders) > 0:
        print("Found %d files with invalid include guards:" % len(invalidHeaders))

        for header in invalidHeaders:
            print("  %s" % header)

        if not fix:
            sys.exit(-1)
    else:
        print("All headers have valid include guards.")

    if fix:
        print("")
        for header in invalidHeaders:
            fixIncludeGuard(header)
            print("Fixed %s" % header)