import os
import xxhash

class FileHash:
    def __init__(self,
                 path_file,
                 chunk_size=1024 * 1024,
                 *args,
                 **kwargs):
        super(FileHash,self).__init__(*args,**kwargs)
        self.path_file          = path_file
        self._path              = os.path.dirname(self.path_file)
        self.chunk_size         = chunk_size
        self.path_hasher = xxhash.xxh64(self.path_file)
        # noinspection PyArgumentList
        # self.file_hash          = self.get_hash(self.path_file)
        self.path_hash          = self.hash_path()

    def get_hash(self,f,
                 progress_callback,
                 current_file_progress_callback,
                 imported_file_count_callback,
                 found_file_callback,
                 total_file_count_callback,
                 checksum_file_callback,
                 checksum_progress_callback,
                 checksum_dialog_open_callback,
                 compare_checksums_source_file_callback,
                 compare_checksums_dest_file_callback,
                 compare_checksums_source_hash_callback,
                 compare_checksums_dest_hash_callback,
                 compare_checksums_add_row_callback):

        checksum_dialog_open_callback.emit(True)

        size                    = os.path.getsize(f)
        hasher                  = xxhash.xxh64()

        chunk_count             = 0

        checksum_file_callback.emit(f)

        with open(f, 'rb') as f:
            for chunk in iter(lambda: f.read(self.chunk_size),b""):
                hasher.update(chunk)
                chunk_count     += 1
                hashed_size     = chunk_count * self.chunk_size
                checksum_progress_callback.emit(round((hashed_size / size) * 100, 1))

        file_hash               = hasher.hexdigest()
        checksum_dialog_open_callback.emit(False)

        return file_hash

    def hash_path(self):
        """ hashes a string passed as a path """

        return self.path_hasher.hexdigest()