#!/usr/bin/python
# ==========================================================================
#
#   Copyright NumFOCUS
#
#   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
#
#          https://www.apache.org/licenses/LICENSE-2.0.txt
#
#   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.
#
# ==========================================================================*/


## Author: Hans J. Johnson
## This script is designed to find redundant header files
## For a given file, if a sibling include file has a
## grand-child include file that is the same, then
## you can remove the sibling include.

## in the ITK/Code directory issue the following command

import os
import sys
import re
import collections


class FileToPathMapping:
    def __init__(self):
        self.filePathBaseDirs = dict()
        self.DependUponTree_dict = collections.defaultdict(list)

    def getBaseDirs(self):
        return self.filePathBaseDirs

    def FillFromWalkingTree(self, basedir):
        os.path.walk(basedir, makeGlobalMapping, self.filePathBaseDirs)
        for all_files in self.filePathBaseDirs:
            testfile = self.filePathBaseDirs[all_files] + "/" + all_files
            curr_file = os.path.basename(testfile)
            curr_dir = os.path.dirname(testfile)
            if not os.path.isfile(testfile):
                continue
            # print(testfile)
            ff = open(testfile)
            search_string = r'^#include *([<"])(itk[^<"]*h)([>"])'
            myregexp = re.compile(search_string)
            for line in ff:
                gg = myregexp.match(line)
                if gg != None and (len(gg.groups()) == 3):
                    inc = gg.group(2)
                    # make empty list if not found already
                    self.DependUponTree_dict[inc]
                    self.DependUponTree_dict[curr_file].append(inc)
                    # print("{0} in {1}".format(inc,curr_file))
            ff.close()
        return self.DependUponTree_dict

    def comment_out(self, filename, remove_header):
        """Get rid of include lines that are redundant"""
        ff = open(self.filePathBaseDirs[filename] + "/" + filename)
        outfile = open(
            self.filePathBaseDirs[filename] + "/" + filename + "_cleaned", "w"
        )
        for line in ff:
            if line.find(remove_header) != -1:
                print(
                    "          Removing {} from {}".format(
                        line, self.filePathBaseDirs[filename] + "/" + filename
                    )
                )
            else:
                outfile.write(line)
        ff.close()
        outfile.close()
        os.rename(
            self.filePathBaseDirs[filename] + "/" + filename + "_cleaned",
            self.filePathBaseDirs[filename] + "/" + filename,
        )

    def proc_children(self, node, dupcandidate, starting_child):
        ## Process all children
        isdone = donenode.get((starting_child, dupcandidate), None)
        if isdone != None:
            # print("found {0} {1}".format(starting_child,dupcandidate))
            return False
        else:
            # print("adding {0} {1}".format(starting_child,dupcandidate))
            donenode[(starting_child, dupcandidate)] = True

        nodeEdges = myDependTree[node]
        # print(nodeEdges)
        if dupcandidate not in nodeEdges:  # Nothing to do
            print("-")
            return False
        elif len(nodeEdges) == 0:  ## leaf node
            print("l")
            return False
        else:
            for currEdge in nodeEdges:
                if dupcandidate in myDependTree[currEdge]:
                    print(
                        "Remove {} from {}:  found hereditary same include in {}".format(
                            dupcandidate, starting_child, currEdge
                        )
                    )
                    ## Update Mapping to remove race condition where an include is removed
                    ## after it is referenced as a hereditary source
                    # print("{0} --> {1}".format(starting_child,myDependTree[starting_child]))
                    temp = myDependTree[starting_child]
                    temp.remove(dupcandidate)
                    myDependTree[node] = temp
                    # print("{0} --> {1}".format(starting_child,myDependTree[starting_child]))
                    self.comment_out(starting_child, dupcandidate)
                    return True
                else:
                    # print("Processsng proc_childeren({0},{1},{2})".format(currEdge,dupcandidate,starting_child))
                    self.proc_children(currEdge, dupcandidate, starting_child)
        return False


basedir = sys.argv[
    1
]  ## i.e. python FindRedundantHeaderIncludes.py $HOME/Dashboards/ITK_TESTS/ITK
if os.path.isfile(
    basedir + "/Documentation/InsightLogo.gif"
):  ## Currently hard-coded to only work with ITK dir.
    print(f"Processing: {basedir}")
else:
    print(f"The directory must be the base ITK dir: {basedir} failed")
    exit(-1)

mymapper = FileToPathMapping()
myDependTree = mymapper.FillFromWalkingTree(basedir)

# for parentFiles in myDependTree:
#    print(parentFiles)
#    for childFiles in myDependTree[parentFiles]:
#        print(" "*3+childFiles)
# print(mymapper.filePathBaseDirs)


donenode = dict()
distance = 0

file_count = 0
# process_file="itkMatrixOffsetTransformBase.h"
# process_file="itkConstNeighborhoodIterator.h"
# for process_file in ["itkImage.h"]:
for process_file in myDependTree.keys():
    for remove_test_file in myDependTree[process_file]:
        # print("Starting test for: {0} and {1}".format(process_file,remove_test_file))
        mymapper.proc_children(process_file, remove_test_file, process_file)
        file_count += 1
print(f"Processed {file_count} files.")