#!/usr/bin/env python3
# encoding: utf-8

##
# This script checks all media files in the repository for whether they've been modified or added without updating the file tracking image, sound, and music copyright
##

import argparse
import contextlib
import csv
import hashlib
from operator import itemgetter
import os
from pathlib import Path
from subprocess import check_output
import sys

##
# csv file layout:
# [0] = current git commit date
# [1] = file path, relative to the repository root
# [2] = license name(s)
# [3] = authorship information
# [4] = notes
# [5] = new git commit date, if different from the value in [0]
# [6] = current md5 hash
##

def do_git(file):
    return str(check_output(["git", "log", "-1", "--format=%ad", "--date=format:%Y/%m/%d", file]), 'UTF-8').rstrip('\n')

def do_hash(file):
    md5 = hashlib.md5()
    with open(file, 'rb') as f:
        while True:
            data = f.read(65536)
            if not data:
                break
            md5.update(data)
    return str(md5.hexdigest())

##
# program logic start
##

args = argparse.ArgumentParser()
args.add_argument("--repo", default=".", help="The directory of the Wesnoth repository to run this script against.")
args.add_argument("--output", default="output.csv", help="The file to write the results of this script to.")
args.add_argument("--input", default="copyrights.csv", help="The file to read the existing copyright data from.")
options = args.parse_args()
os.chdir(options.repo)

with contextlib.suppress(FileNotFoundError):
    os.remove(options.output)

csv_data = {}
added = []
changed = []
unchanged = []
removed = []

with open(options.input) as csvfile:
    reader = csv.reader(csvfile)
    for row in reader:
        if row[0] == "Date":
            continue

        file = row[1]

        if not os.path.exists(file):
            removed.append(file)
            continue

        csv_data[file] = row

for root, _, files in os.walk(options.repo):
    for filename in files:
        filetype = Path(filename).suffix
        if filetype == ".png" or filetype == ".jpg" or filetype == ".webp" or filetype == ".wav" or filetype == ".ogg":
            file = os.path.normpath(os.path.join(root, filename))
            hash = do_hash(file)

            if not file in csv_data:
                added.append(["", file, "", "", "", do_git(file), hash])
            elif csv_data[file][6] != hash:
                csv_data[file][5] = do_git(file)
                csv_data[file][6] = hash
                changed.append(csv_data[file])
            else:
                unchanged.append(csv_data[file])

added.sort(key=itemgetter(1))
changed.sort(key=itemgetter(1))
unchanged.sort(key=itemgetter(1))

final_output = added + changed + unchanged

if options.output != "":
    with open(options.output, 'w') as f:
        f.write("Date,File,License,Author - Real Name(other name);Real Name(other name);etc,Notes,Needs Update,MD5\n")
        for row in final_output:
            f.write(",".join(row)+"\n")
else:
    for row in final_output:
        print(",".join(row))

if len(removed) > 0:
    print("There are "+str(len(removed))+" removed images")

if len(added) > 0 or len(changed) > 0:
    print("There are "+str(len(added))+" new images")
    print("There are "+str(len(changed))+" changed images")
    sys.exit(1)