# © 2016 James R. Barlow: github.com/jbarlow83
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.


from enum import IntEnum
from textwrap import dedent


class ExitCode(IntEnum):
    ok = 0
    bad_args = 1
    input_file = 2
    missing_dependency = 3
    invalid_output_pdf = 4
    file_access_error = 5
    already_done_ocr = 6
    child_process_error = 7
    encrypted_pdf = 8
    invalid_config = 9
    pdfa_conversion_failed = 10
    other_error = 15
    ctrl_c = 130


class ExitCodeException(Exception):
    exit_code = ExitCode.other_error
    message = ""

    def __str__(self):
        super_msg = super().__str__()  # Don't do str(super())
        if self.message:
            return self.message.format(super_msg)
        return super_msg


class BadArgsError(ExitCodeException):
    exit_code = ExitCode.bad_args


class PdfMergeFailedError(ExitCodeException):
    exit_code = ExitCode.input_file
    message = dedent(
        '''\
        Failed to merge PDF image layer with OCR layer

        Usually this happens because the input PDF file is malformed and
        ocrmypdf cannot automatically correct the problem on its own.

        Try using
            ocrmypdf --pdf-renderer sandwich  [..other args..]
        '''
    )


class MissingDependencyError(ExitCodeException):
    exit_code = ExitCode.missing_dependency


class UnsupportedImageFormatError(ExitCodeException):
    exit_code = ExitCode.input_file


class DpiError(ExitCodeException):
    exit_code = ExitCode.input_file


class OutputFileAccessError(ExitCodeException):
    exit_code = ExitCode.file_access_error


class PriorOcrFoundError(ExitCodeException):
    exit_code = ExitCode.already_done_ocr


class InputFileError(ExitCodeException):
    exit_code = ExitCode.input_file


class SubprocessOutputError(ExitCodeException):
    exit_code = ExitCode.child_process_error


class EncryptedPdfError(ExitCodeException):
    exit_code = ExitCode.encrypted_pdf
    message = dedent(
        '''\
        Input PDF is encrypted. The encryption must be removed to
        perform OCR.

        For information about this PDF's security use
            qpdf --show-encryption infilename

        You can remove the encryption using
            qpdf --decrypt [--password=[password]] infilename
        '''
    )


class TesseractConfigError(ExitCodeException):
    exit_code = ExitCode.invalid_config
    message = "Error occurred while parsing a Tesseract configuration file"