#!/usr/bin/env python3

# dupFinder.py
import os, sys
import hashlib


# Find duplicates
def findDup(parentFolder):
# Dups in format {hash:[names]}
        dups = {}
        sizes = {}
        for dirName, subdirs, fileList in os.walk(parentFolder):
                print('Scanning %s...' % dirName)
                for filename in fileList:
                        # Get the path to the file
                        path = os.path.join(dirName, filename)
                        if os.path.isfile(path):
                                fsize = os.stat(path).st_size
                                if fsize in sizes:
                                        sizes[fsize].append(path)
                                else:
                                        sizes[fsize] = [path]
        print('Calculating hashes...')
        # For same size calculate hashes
        for paths in sizes.values():
                if len(paths) > 1:
                        for path in paths:
                                file_hash = hashfile(path)
                                # Add or append the file path
                                if file_hash in dups:
                                        dups[file_hash].append(path)
                                else:
                                        dups[file_hash] = [path]
        return dups


# Joins two dictionaries
def joinDicts(dict1, dict2):
        for key in dict2.keys():
                if key in dict1:
                        dict1[key] = dict1[key] + dict2[key]
                else:
                        dict1[key] = dict2[key]


# Compute hash
def hashfile(path, blocksize = 65536):
        afile = open(path, 'rb')
        hasher = hashlib.md5()
        buf = afile.read(blocksize)
        while len(buf) > 0:
                hasher.update(buf)
                buf = afile.read(blocksize)
        afile.close()
        return hasher.hexdigest()


# Print output
def printResults(dict1):
        results = list(filter(lambda x: len(x) > 1, dict1.values()))
        if len(results) > 0:
                print('Duplicates Found:')
                print('The following files are identical. The name could differ, but the content is identical')
                print('___________________')
                for result in results:
                        for subresult in result:
                                print('%s' % subresult)
                        print('___________________')

        else:
                print('No duplicate files found.')


# Main 
if __name__ == '__main__':
        if len(sys.argv) > 1:
                dups = {}
                folders = sys.argv[1:]
                for i in folders:
            # Iterate the folders given
                        if os.path.exists(i):
                                # Find the duplicated files and append them to the dups
                                joinDicts(dups, findDup(i))
                        else:
                                print('%s is not a valid path, please verify' % i)
                                sys.exit()
                printResults(dups)
        else:
                print('Usage: python dupFinder.py folder or python dupFinder.py folder1 folder2')