#
# diffoscope: in-depth comparison of files, archives, and directories
#
# Copyright © 2014-2015 Jérémy Bobbio <lunar@debian.org>
# Copyright ©      2015  Helmut Grohne <helmut@subdivi.de>
# Copyright © 2015-2022 Chris Lamb <lamby@debian.org>
#
# diffoscope is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# diffoscope is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with diffoscope.  If not, see <https://www.gnu.org/licenses/>.

import sys
import logging
import importlib
import traceback

from ..tools import python_module_missing
from ..logging import line_eraser


logger = logging.getLogger(__name__)


class ComparatorManager:
    COMPARATORS = (
        ("directory.Directory",),
        ("missing_file.MissingFile",),
        ("symlink.Symlink",),
        ("device.Device",),
        ("socket_or_fifo.SocketOrFIFO",),
        ("debian.DotChangesFile", "debian_fallback.DotChangesFile"),
        ("debian.DotDscFile", "debian_fallback.DotDscFile"),
        ("debian.DotBuildinfoFile", "debian_fallback.DotBuildinfoFile"),
        ("deb.Md5sumsFile",),
        ("deb.DebDataTarFile",),
        ("decompile.AsmFunction",),
        ("elf.ElfSection",),
        ("macho.MachoSection",),
        ("macho.MachoArchitecture",),
        ("binwalk.BinwalkFile",),
        ("ps.PsFile",),
        ("javascript.JavaScriptFile",),
        ("json.JSONFile",),
        ("xml.XMLFile",),
        ("xmlb.XMLBFile",),
        ("openssl.Pkcs7File",),
        ("openssl.MobileProvisionFile",),
        ("html.HtmlFile",),
        ("text.TextFile",),
        ("bzip2.Bzip2File",),
        ("cpio.CpioFile",),
        ("deb.DebFile",),
        ("hdf.Hdf5File",),
        ("dex.DexFile",),
        ("elf.ElfFile",),
        ("macho.MachoFile",),
        ("fsimage.FsImageFile",),
        ("llvm.LlvmBitCodeFile",),
        ("sqlite.Sqlite3Database",),
        ("wasm.WasmFile",),
        ("fonts.TtfFile",),
        ("fontconfig.FontconfigCacheFile",),
        ("gettext.MoFile",),
        ("ipk.IpkFile",),
        ("rust.RustObjectFile",),
        ("ffprobe.FfprobeFile",),
        ("gnumeric.GnumericFile",),
        ("gzip.GzipFile",),
        ("haskell.HiFile",),
        ("icc.IccFile",),
        ("iso9660.Iso9660File",),
        ("java.ClassFile",),
        ("lz4.Lz4File",),
        ("lzip.LzipFile",),
        ("mono.MonoExeFile",),
        ("pdf.PdfFile",),
        ("png.PngFile",),
        ("ppu.PpuFile",),
        ("rdata.RdbFile",),
        ("rdata.RdsFile",),
        ("rpm.RpmFile", "rpm_fallback.RpmFile"),
        ("squashfs.SquashfsFile",),
        ("ar.ArFile",),
        ("tar.TarFile",),
        ("xz.XzFile",),
        ("apk.ApkFile",),
        ("odt.OdtFile",),
        ("ocaml.OcamlInterfaceFile",),
        ("docx.DocxFile",),
        ("zip.MozillaZipFile",),
        ("zip.JmodJavaModule",),
        ("zip.ZipFile",),
        ("image.JPEGImageFile",),
        ("image.ICOImageFile",),
        ("cbfs.CbfsFile",),
        ("git.GitIndexFile",),
        ("android.AndroidBootImgFile",),
        ("openssh.PublicKeyFile",),
        ("gif.GifFile",),
        ("pcap.PcapFile",),
        ("pe32.Pe32PlusFile",),
        ("pgp.PgpFile",),
        ("pgp.PgpSignature",),
        ("python.PycFile",),
        ("sphinx.SphinxInventoryFile",),
        ("kbx.KbxFile",),
        ("fit.FlattenedImageTreeFile",),
        ("dtb.DeviceTreeFile",),
        ("ogg.OggFile",),
        ("uimage.UimageFile",),
        ("xsb.XsbFile",),
        ("berkeley_db.BerkeleyDBFile",),
        ("zst.ZstFile",),
        ("vmlinuz.VmlinuzFile",),
        ("arsc.ArscFile",),
    )

    _singleton = {}

    def __init__(self):
        self.__dict__ = self._singleton

        if not self._singleton:
            self.reload()

    def reload(self):
        self.classes = []

        for xs in self.COMPARATORS:
            errors = []
            for x in xs:
                package, klass_name = x.rsplit(".", 1)

                try:
                    mod = importlib.import_module(
                        f"diffoscope.comparators.{package}",
                    )
                except ModuleNotFoundError as e:
                    python_module_missing(e.name)
                    errors.append((x, e))
                    continue
                except ImportError as e:
                    errors.append((x, e))
                    continue

                self.classes.append(getattr(mod, klass_name))
                break
            else:  # noqa
                logger.error(
                    "Could not import {}{}".format(
                        "any of " if len(xs) > 1 else "", ", ".join(xs)
                    )
                )
                for x in errors:
                    logger.error("Original error for %s:", x[0])
                    sys.stderr.buffer.write(line_eraser())
                    traceback.print_exception(None, x[1], x[1].__traceback__)
                sys.exit(2)

        logger.debug("Loaded %d comparator classes", len(self.classes))

    def format_descriptions(self):
        def gen_descriptions():
            for x in self.classes:
                try:
                    yield x.DESCRIPTION
                except AttributeError:
                    pass

        xs = list(sorted(set(gen_descriptions()), key=str.upper))

        return "{} and {}.\n".format(", ".join(xs[:-1]), xs[-1])
