import os
from collections import defaultdict

from eyed3.id3 import ID3_V2_4
from eyed3.id3.tag import TagTemplate
from eyed3.plugins import LoaderPlugin
from eyed3.utils import art
from eyed3.utils.prompt import prompt
from eyed3.utils.console import printMsg, Style, Fore
from eyed3 import core

from eyed3.core import (ALBUM_TYPE_IDS, TXXX_ALBUM_TYPE, EP_MAX_SIZE_HINT,
                        LP_TYPE, EP_TYPE, COMP_TYPE, VARIOUS_TYPE, DEMO_TYPE,
                        LIVE_TYPE, SINGLE_TYPE, VARIOUS_ARTISTS)

NORMAL_FNAME_FORMAT = "${artist} - ${track:num} - ${title}"
VARIOUS_FNAME_FORMAT = "${track:num} - ${artist} - ${title}"
SINGLE_FNAME_FORMAT = "${artist} - ${title}"

NORMAL_DNAME_FORMAT = "${best_date:prefer_release} - ${album}"
LIVE_DNAME_FORMAT = "${best_date:prefer_recording} - ${album}"


def _printChecking(msg, end='\n'):
    print(Style.BRIGHT + Fore.GREEN + "Checking" + Style.RESET_ALL + " %s" % msg, end=end)


def _fixCase(s):
    if s:
        fixed_values = []
        for word in s.split():
            fixed_values.append(word.capitalize())
        return " ".join(fixed_values)
    else:
        return s


def dirDate(d):
    s = str(d)
    if "T" in s:
        s = s.split("T")[0]
    return s.replace('-', '.')


class FixupPlugin(LoaderPlugin):
    NAMES = ["fixup"]
    SUMMARY = "Performs various checks and fixes to directories of audio files."
    DESCRIPTION = """
Operates on directories at a time, fixing each as a unit (album,
compilation, live set, etc.). All of these should have common dates,
for example but other characteristics may vary. The ``--type`` should be used
whenever possible, ``lp`` is the default.

The following test and fixes always apply:

    1.  Every file will be given an ID3 tag if one is missing.
    2.  Set ID3 v2.4.
    3.  Set a consistent album name for all files in the directory.
    4.  Set a consistent artist name for all files, unless the type is
        ``various`` in which case the artist may vary (but must exist).
    5.  Ensure each file has a title.
    6.  Ensure each file has a track # and track total.
    7.  Ensure all files have a release and original release date, unless the
        type is ``live`` in which case the recording date is set.
    8.  All ID3 frames of the following types are removed: USER, PRIV
    9.  All ID3 files have TLEN (track length in ms) set (or updated).
    10. The album/dir type is set in the tag. Types of ``lp`` and ``various``
        do not have this field set since the latter is the default and the
        former can be determined during sync. In ID3 terms the value is in
        TXXX (description: ``%(TXXX_ALBUM_TYPE)s``).
    11. Files are renamed as follows:
        - Type ``various``: %(VARIOUS_FNAME_FORMAT)s
        - Type ``single``: %(SINGLE_FNAME_FORMAT)s
        - All other types: %(NORMAL_FNAME_FORMAT)s
        - A rename template can be supplied in --file-rename-pattern
    12. Directories are renamed as follows:
        - Type ``live``: %(LIVE_DNAME_FORMAT)s
        - All other types: %(NORMAL_DNAME_FORMAT)s
        - A rename template can be supplied in --dir-rename-pattern

Album types:

    - ``lp``: A traditinal "album" of songs from a single artist.
      No extra info is written to the tag since this is the default.
    - ``ep``: A short collection of songs from a single artist. The string 'ep'
      is written to the tag's ``%(TXXX_ALBUM_TYPE)s`` field.
    - ``various``: A collection of songs from different artists. The string
      'various' is written to the tag's ``%(TXXX_ALBUM_TYPE)s`` field.
    - ``live``: A collection of live recordings from a single artist. The string
      'live' is written to the tag's ``%(TXXX_ALBUM_TYPE)s`` field.
    - ``compilation``: A collection of songs from various recordings by a single
      artist. The string 'compilation' is written to the tag's
      ``%(TXXX_ALBUM_TYPE)s`` field. Compilation dates, unlike other types, may
      differ.
    - ``demo``: A demo recording by a single artist. The string 'demo' is
      written to the tag's ``%(TXXX_ALBUM_TYPE)s`` field.
    - ``single``: A track that should no be associated with an album (even if
      it has album metadata). The string 'single' is written to the tag's
      ``%(TXXX_ALBUM_TYPE)s`` field.

""" % globals()

    def __init__(self, arg_parser):
        super(FixupPlugin, self).__init__(arg_parser, cache_files=True,
                                          track_images=True)
        g = self.arg_group
        self._handled_one = False

        g.add_argument("--type", choices=ALBUM_TYPE_IDS, dest="dir_type",
                       default=None, help=ARGS_HELP["--type"])
        g.add_argument("--fix-case", action="store_true", dest="fix_case",
                       help=ARGS_HELP["--fix-case"])
        g.add_argument("-n", "--dry-run", action="store_true", dest="dry_run",
                       help=ARGS_HELP["--dry-run"])
        g.add_argument("--no-prompt", action="store_true", dest="no_prompt",
                       help=ARGS_HELP["--no-prompt"])
        g.add_argument("--dotted-dates", action="store_true",
                       help=ARGS_HELP["--dotted-dates"])
        g.add_argument("--file-rename-pattern", dest="file_rename_pattern",
                       help=ARGS_HELP["--file-rename-pattern"])
        g.add_argument("--dir-rename-pattern", dest="dir_rename_pattern",
                       help=ARGS_HELP["--dir-rename-pattern"])
        g.add_argument("--no-dir-rename", action="store_true",
                       help=ARGS_HELP["--no-dir-rename"])
        self._curr_dir_type = None
        self._dir_files_to_remove = set()

    def _getOne(self, key, values, default=None, Type=str,
                required=True):
        values = set(values)
        if None in values:
            values.remove(None)

        if len(values) != 1:
            printMsg(
                "Detected %s %s names%s" %
                ("0" if len(values) == 0 else "multiple",
                 key,
                 "." if not values
                     else (":\n\t%s" % "\n\t".join([str(v) for v in values])),
                ))

            value = prompt("Enter %s" % key.title(), default=default,
                           type_=Type, required=required)
        else:
            value = values.pop()

        return value

    def _getDates(self, audio_files):
        tags = [f.tag for f in audio_files if f.tag]

        rel_dates = set([t.release_date for t in tags if t.release_date])
        orel_dates = set([t.original_release_date for t in tags
                          if t.original_release_date])
        rec_dates = set([t.recording_date for t in tags if t.recording_date])

        release_date, original_release_date, recording_date = None, None, None

        def reduceDate(type_str, dates_set, default_date=None):
            if len(dates_set or []) != 1:
                reduced = self._getOne(type_str, dates_set,
                                       default=str(default_date) if default_date
                                                                 else None,
                                       Type=core.Date.parse)
            else:
                reduced = dates_set.pop()
            return reduced

        if (False not in [a.tag.album_type == LIVE_TYPE for a in audio_files] or
                self._curr_dir_type == LIVE_TYPE):
            # The recording date is most meaningful for live music.
            recording_date = reduceDate("recording date",
                                        rec_dates | orel_dates | rel_dates)
            rec_dates = {recording_date}

            # Want when these set if they may recording time.
            orel_dates.difference_update(rec_dates)
            rel_dates.difference_update(rec_dates)

            if orel_dates:
                original_release_date = reduceDate("original release date",
                                                   orel_dates | rel_dates)
            orel_dates = {original_release_date}

            if rel_dates | orel_dates:
                release_date = reduceDate("release date",
                                          rel_dates | orel_dates)
        elif (False not in [a.tag.album_type == COMP_TYPE
                            for a in audio_files] or
              self._curr_dir_type == COMP_TYPE):
            # The release date is most meaningful for comps, other track dates
            # may differ.
            if len(rel_dates) != 1:
                release_date = reduceDate("release date", rel_dates | orel_dates)
            else:
                release_date = list(rel_dates)[0]
        else:
            if len(orel_dates) != 1:
                # The original release date is most meaningful for studio music.
                original_release_date = reduceDate("original release date",
                                                   orel_dates | rel_dates | rec_dates)
                orel_dates = {original_release_date}
            else:
                original_release_date = list(orel_dates)[0]

            if len(rel_dates) != 1:
                release_date = reduceDate("release date", rel_dates | orel_dates)
                rel_dates = {release_date}
            else:
                release_date = list(rel_dates)[0]

            if rec_dates.difference(orel_dates | rel_dates):
                recording_date = reduceDate("recording date", rec_dates)

        return release_date, original_release_date, recording_date

    def _resolveArtistInfo(self, audio_files):
        assert(self._curr_dir_type != SINGLE_TYPE)

        tags = [f.tag for f in audio_files if f.tag]
        artists = set([t.album_artist for t in tags if t.album_artist])

        # There can be 0 or 1 album artist values.
        album_artist = None
        if len(artists) > 1:
            album_artist = self._getOne("album artist", artists, required=False)
        elif artists:
            album_artist = artists.pop()

        artists = list(set([t.artist for t in tags if t.artist]))

        if len(artists) > 1:
            # There can be more then 1 artist when VARIOUS_TYPE or
            # album_artist != None.
            if not album_artist and self._curr_dir_type != VARIOUS_TYPE:
                if prompt("Multiple artist names exist, process directory as "
                          "various artists", default=True):
                    self._curr_dir_type = VARIOUS_TYPE
                else:
                    artists = [self._getOne("artist", artists, required=True)]
            elif (album_artist == VARIOUS_ARTISTS and
                    self._curr_dir_type != VARIOUS_TYPE):
                self._curr_dir_type = VARIOUS_TYPE
        elif len(artists) == 0:
            artists = [self._getOne("artist", [], required=True)]

        # Fix up artist and album artist discrepancies
        if len(artists) == 1 and album_artist:
            artist = artists[0]
            if album_artist != artist:
                print("When there is only one artist it should match the "
                      "album artist. Choices are: ")
                for s in [artist, album_artist]:
                    print("\t%s" % s)
                album_artist = prompt("Select common artist and album artist",
                                      choices=[artist, album_artist])
                artists = [album_artist]

        if self.args.fix_case:
            album_artist = _fixCase(album_artist)
            artists = [_fixCase(a) for a in artists]
        return album_artist, artists

    def _getAlbum(self, audio_files):
        tags = [f.tag for f in audio_files if f.tag]
        albums = set([t.album for t in tags if t.album])
        album_name = (albums.pop() if len(albums) == 1
                                   else self._getOne("album", albums))
        assert album_name
        return album_name if not self.args.fix_case else _fixCase(album_name)

    def _checkCoverArt(self, directory, audio_files):
        valid_cover = False

        # Check for cover file.
        _printChecking("for cover art...")
        for dimg in self._dir_images:
            art_type = art.matchArtFile(dimg)
            if art_type == art.FRONT_COVER:
                dimg_name = os.path.basename(dimg)
                print(f"\t{dimg_name}")
                valid_cover = True

        if not valid_cover:
            # FIXME: move the logic out fixup and into art.
            #  Look for a cover in the tags.
            for tag in [af.tag for af in audio_files if af.tag]:
                if valid_cover:
                    # It could be set below...
                    break
                for img in tag.images:
                    if img.picture_type == img.FRONT_COVER:
                        file_name = img.makeFileName("cover")
                        print("\tFound front cover in tag, writing '%s'" % file_name)
                        with open(os.path.join(directory, file_name), "wb") as img_file:
                            img_file.write(img.image_data)
                            img_file.close()
                            valid_cover = True

        # TODO: force rename of cover file to single/consistent name (e.g. cover)

        return valid_cover

    def start(self, args, config):
        import eyed3.utils.prompt
        eyed3.utils.prompt.DISABLE_PROMPT = "exit" if args.no_prompt else None

        super(FixupPlugin, self).start(args, config)

    def handleFile(self, f, *args, **kwargs):
        super(FixupPlugin, self).handleFile(f, *args, **kwargs)
        if not self.audio_file and f not in self._dir_images:
            self._dir_files_to_remove.add(f)

    def handleDirectory(self, directory, _):
        if not self._file_cache:
            return

        directory = os.path.abspath(directory)
        print("\n" + Style.BRIGHT + Fore.YELLOW +
              "Scanning directory%s %s" % (Style.RESET_ALL, directory))

        def _path(af):
            return af.path

        self._handled_one = True

        # Make sure all of the audio files has a tag.
        for f in self._file_cache:
            if f.tag is None:
                f.initTag()

        audio_files = sorted(list(self._file_cache), key=_path)

        self._file_cache = []
        edited_files = set()
        self._curr_dir_type = self.args.dir_type
        if self._curr_dir_type is None:
            types = set([a.tag.album_type for a in audio_files])
            if len(types) == 1:
                self._curr_dir_type = types.pop()

        # Check for corrections to LP, EP, COMP
        if (self._curr_dir_type is None and
                    len(audio_files) < EP_MAX_SIZE_HINT):
            # Do you want EP?
            if False in [a.tag.album_type == EP_TYPE for a in audio_files]:
                if prompt("Only %d audio files, process directory as an EP" %
                          len(audio_files),
                          default=True):
                    self._curr_dir_type = EP_TYPE
            else:
                self._curr_dir_type = EP_TYPE
        elif (self._curr_dir_type in (EP_TYPE, DEMO_TYPE) and
                len(audio_files) > EP_MAX_SIZE_HINT):
            # Do you want LP?
            if prompt("%d audio files is large for type %s, process "
                      "directory as an LP" % (len(audio_files),
                                              self._curr_dir_type),
                      default=True):
                self._curr_dir_type = LP_TYPE

        last = defaultdict(lambda: None)

        album_artist = None
        artists = set()
        album = None

        if self._curr_dir_type != SINGLE_TYPE:
            album_artist, artists = self._resolveArtistInfo(audio_files)
            print(Fore.BLUE + "Album artist: " + Style.RESET_ALL +
                  (album_artist or ""))
            print(Fore.BLUE + "Artist" + ("s" if len(artists) > 1 else "") +
                  ": " + Style.RESET_ALL + ", ".join(artists))

            album = self._getAlbum(audio_files)
            print(Fore.BLUE + "Album: " + Style.RESET_ALL + album)

            rel_date, orel_date, rec_date = self._getDates(audio_files)
            for what, d in [("Release", rel_date),
                            ("Original", orel_date),
                            ("Recording", rec_date)]:
                print(f"{Fore.BLUE} {what} date: {Style.RESET_ALL} {d}")

            num_audio_files = len(audio_files)
            track_nums = set([f.tag.track_num[0] for f in audio_files])
            fix_track_nums = set(range(1, num_audio_files + 1)) != track_nums
            new_track_nums = []

        dir_type = self._curr_dir_type
        for f in sorted(audio_files, key=_path):
            print(Style.BRIGHT + Fore.GREEN + "Checking" + Fore.RESET +
                  Style.BRIGHT + (" %s" % os.path.basename(f.path)) +
                  Style.RESET_ALL)

            if not f.tag:
                print("\tAdding new tag")
                f.initTag()
                edited_files.add(f)
            tag = f.tag

            if tag.version != ID3_V2_4:
                print("\tConverting to ID3 v2.4")
                tag.version = ID3_V2_4
                edited_files.add(f)

            if dir_type != SINGLE_TYPE and album_artist != tag.album_artist:
                print("\tSetting album artist: %s" % album_artist)
                tag.album_artist = album_artist
                edited_files.add(f)

            if not tag.artist and dir_type in (VARIOUS_TYPE, SINGLE_TYPE):
                # Prompt artist
                tag.artist = prompt("Artist name", default=last["artist"])
                last["artist"] = tag.artist
            elif len(artists) == 1 and tag.artist != artists[0]:
                assert(dir_type != SINGLE_TYPE)
                print("\tSetting artist: %s" % artists[0])
                tag.artist = artists[0]
                edited_files.add(f)

            if tag.album != album and dir_type != SINGLE_TYPE:
                print("\tSetting album: %s" % album)
                tag.album = album
                edited_files.add(f)

            orig_title = tag.title
            if not tag.title:
                tag.title = prompt("Track title")
            tag.title = tag.title.strip()
            if self.args.fix_case:
                tag.title = _fixCase(tag.title)
            if orig_title != tag.title:
                print("\tSetting title: %s" % tag.title)
                edited_files.add(f)

            if dir_type != SINGLE_TYPE:
                # Track numbers
                tnum, ttot = tag.track_num
                update = False
                if ttot != num_audio_files:
                    update = True
                    ttot = num_audio_files

                if fix_track_nums or not (1 <= tnum <= num_audio_files):
                    tnum = None
                    while tnum is None:
                        tnum = int(prompt("Track #", type_=int))
                        if not (1 <= tnum <= num_audio_files):
                            print(Fore.RED + "Out of range: " + Fore.RESET +
                                  "1 <= %d <= %d" % (tnum, num_audio_files))
                            tnum = None
                        elif tnum in new_track_nums:
                            print(Fore.RED + "Duplicate value: " + Fore.RESET +
                                    str(tnum))
                            tnum = None
                        else:
                            update = True
                            new_track_nums.append(tnum)

                if update:
                    tag.track_num = (tnum, ttot)
                    print("\tSetting track numbers: %s" % str(tag.track_num))
                    edited_files.add(f)
            else:
                # Singles
                if tag.track_num != (None, None):
                    tag.track_num = (None, None)
                    edited_files.add(f)

            if dir_type != SINGLE_TYPE:
                # Dates
                if rec_date and tag.recording_date != rec_date:
                    print("\tSetting %s date (%s)" %
                            ("recording", str(rec_date)))
                    tag.recording_date = rec_date
                    edited_files.add(f)
                if rel_date and tag.release_date != rel_date:
                    print("\tSetting %s date (%s)" % ("release", str(rel_date)))
                    tag.release_date = rel_date
                    edited_files.add(f)
                if orel_date and tag.original_release_date != orel_date:
                    print("\tSetting %s date (%s)" % ("original release",
                                                      str(orel_date)))
                    tag.original_release_date = orel_date
                    edited_files.add(f)

            for frame in list(tag.frameiter(["USER", "PRIV"])):
                print("\tRemoving %s frames: %s" %
                        (frame.id,
                         frame.owner_id if frame.id == b"PRIV" else frame.text))
                tag.frame_set[frame.id].remove(frame)
                edited_files.add(f)

            # Add TLEN
            tlen = tag.getTextFrame("TLEN")
            if tlen is not None:
                real_tlen_ms = f.info.time_secs * 1000
                tlen_ms = float(tlen)
                if tlen_ms != real_tlen_ms:
                    print("\tSetting TLEN (%d)" % real_tlen_ms)
                    tag.setTextFrame("TLEN", str(real_tlen_ms))
                    edited_files.add(f)

            # Add custom album type if special and otherwise not able to be
            # determined.
            curr_type = tag.album_type
            if curr_type != dir_type:
                print("\tSetting %s = %s" % (TXXX_ALBUM_TYPE, dir_type))
                tag.album_type = dir_type
                edited_files.add(f)

        try:
            if not self._checkCoverArt(directory, audio_files):
                if not prompt("Proceed without valid cover file", default=True):
                    return
        finally:
            self._dir_images = []

        # Determine other changes, like file and/or directory renames
        # so they can be reported before save confirmation.

        # File renaming
        file_renames = []
        if self.args.file_rename_pattern:
            format_str = self.args.file_rename_pattern
        else:
            if dir_type == SINGLE_TYPE:
                format_str = SINGLE_FNAME_FORMAT
            elif dir_type in (VARIOUS_TYPE, COMP_TYPE):
                format_str = VARIOUS_FNAME_FORMAT
            else:
                format_str = NORMAL_FNAME_FORMAT

        for f in audio_files:
            orig_name, orig_ext = os.path.splitext(os.path.basename(f.path))
            new_name = TagTemplate(format_str).substitute(f.tag, zeropad=True)
            if orig_name != new_name:
                printMsg("Rename file to %s%s" % (new_name, orig_ext))
                file_renames.append((f, new_name, orig_ext))

        # Directory renaming
        dir_rename = None
        if not self.args.no_dir_rename and dir_type != SINGLE_TYPE:
            if self.args.dir_rename_pattern:
                dir_format = self.args.dir_rename_pattern
            else:
                if dir_type == LIVE_TYPE:
                    dir_format = LIVE_DNAME_FORMAT
                else:
                    dir_format = NORMAL_DNAME_FORMAT
            template = TagTemplate(dir_format,
                                   dotted_dates=self.args.dotted_dates)

            pref_dir = template.substitute(audio_files[0].tag, zeropad=True)
            if os.path.basename(directory) != pref_dir:
                new_dir = os.path.join(os.path.dirname(directory), pref_dir)
                printMsg("Rename directory to %s" % new_dir)
                dir_rename = (directory, new_dir)

        # Cruft files to remove
        file_removes = []
        if self._dir_files_to_remove:
            for f in self._dir_files_to_remove:
                print("Remove file: " + os.path.basename(f))
                file_removes.append(f)
        self._dir_files_to_remove = set()

        if not self.args.dry_run:
            confirmed = False

            if (edited_files or file_renames or dir_rename or file_removes):
                confirmed = prompt("\nSave changes", default=True)

            if confirmed:
                for f in edited_files:
                    print("Saving %s" % os.path.basename(f.path))
                    f.tag.save(version=ID3_V2_4, preserve_file_time=True)

                for f, new_name, orig_ext in file_renames:
                    printMsg("Renaming file to %s%s" % (new_name, orig_ext))
                    f.rename(new_name, preserve_file_time=True)

                if file_removes:
                    for f in file_removes:
                        printMsg("Removing file %s" % os.path.basename(f))
                        os.remove(f)

                if dir_rename:
                    printMsg("Renaming directory to %s" % dir_rename[1])
                    s = os.stat(dir_rename[0])
                    os.rename(dir_rename[0], dir_rename[1])
                    # With a rename use the origianl access time
                    os.utime(dir_rename[1], (s.st_atime, s.st_atime))

        else:
            printMsg("\nNo changes made (run without -n/--dry-run)")

    def handleDone(self):
        if not self._handled_one:
            printMsg("Nothing to do")


def _getTemplateKeys():
    from eyed3.id3.tag import TagTemplate

    keys = list(TagTemplate("")._makeMapping(None, False).keys())
    keys.sort()
    return ", ".join(["$%s" % v for v in keys])


ARGS_HELP = {
        "--type": "How to treat each directory. The default is '%s', "
                  "although you may be prompted for an alternate choice "
                  "if the files look like another type." % ALBUM_TYPE_IDS[0],
        "--fix-case": "Fix casing on each string field by capitalizing each "
                      "word.",
        "--dry-run": "Only print the operations that would take place, but do "
                      "not execute them.",
        "--no-prompt": "Exit if prompted.",
        "--dotted-dates": "Separate date with '.' instead of '-' when naming "
                          "directories.",
        "--file-rename-pattern": "Rename file (the extension is not affected) "
                                 "based on data in the tag using substitution "
                                 "variables: " + _getTemplateKeys(),
        "--dir-rename-pattern": "Rename directory based on data in the tag "
                                "using substitution variables: " +
                                _getTemplateKeys(),
        "--no-dir-rename": "Do not rename the directory.",
}
