serializers.py

import logging
import urllib.parse

from django.core.paginator import Paginator
from django.db import transaction
from rest_framework import serializers

from funkwhale_api.common import serializers as common_serializers
from funkwhale_api.common import utils as funkwhale_utils
from funkwhale_api.music import models as music_models
from funkwhale_api.music import tasks as music_tasks

from . import activity, filters, models, utils

AP_CONTEXT = [
    "https://www.w3.org/ns/activitystreams",
    "https://w3id.org/security/v1",
    {},
]

logger = logging.getLogger(__name__)


class ActorSerializer(serializers.Serializer):
    id = serializers.URLField(max_length=500)
    outbox = serializers.URLField(max_length=500)
    inbox = serializers.URLField(max_length=500)
    type = serializers.ChoiceField(choices=models.TYPE_CHOICES)
    preferredUsername = serializers.CharField()
    manuallyApprovesFollowers = serializers.NullBooleanField(required=False)
    name = serializers.CharField(required=False, max_length=200)
    summary = serializers.CharField(max_length=None, required=False)
    followers = serializers.URLField(max_length=500, required=False, allow_null=True)
    following = serializers.URLField(max_length=500, required=False, allow_null=True)
    publicKey = serializers.JSONField(required=False)

    def to_representation(self, instance):
        ret = {
            "id": instance.url,
            "outbox": instance.outbox_url,
            "inbox": instance.inbox_url,
            "preferredUsername": instance.preferred_username,
            "type": instance.type,
        }
        if instance.name:
            ret["name"] = instance.name
        if instance.followers_url:
            ret["followers"] = instance.followers_url
        if instance.following_url:
            ret["following"] = instance.following_url
        if instance.summary:
            ret["summary"] = instance.summary
        if instance.manually_approves_followers is not None:
            ret["manuallyApprovesFollowers"] = instance.manually_approves_followers

        ret["@context"] = AP_CONTEXT
        if instance.public_key:
            ret["publicKey"] = {
                "owner": instance.url,
                "publicKeyPem": instance.public_key,
                "id": "{}#main-key".format(instance.url),
            }
        ret["endpoints"] = {}
        if instance.shared_inbox_url:
            ret["endpoints"]["sharedInbox"] = instance.shared_inbox_url
        return ret

    def prepare_missing_fields(self):
        kwargs = {
            "url": self.validated_data["id"],
            "outbox_url": self.validated_data["outbox"],
            "inbox_url": self.validated_data["inbox"],
            "following_url": self.validated_data.get("following"),
            "followers_url": self.validated_data.get("followers"),
            "summary": self.validated_data.get("summary"),
            "type": self.validated_data["type"],
            "name": self.validated_data.get("name"),
            "preferred_username": self.validated_data["preferredUsername"],
        }
        maf = self.validated_data.get("manuallyApprovesFollowers")
        if maf is not None:
            kwargs["manually_approves_followers"] = maf
        domain = urllib.parse.urlparse(kwargs["url"]).netloc
        kwargs["domain"] = domain
        for endpoint, url in self.initial_data.get("endpoints", {}).items():
            if endpoint == "sharedInbox":
                kwargs["shared_inbox_url"] = url
                break
        try:
            kwargs["public_key"] = self.initial_data["publicKey"]["publicKeyPem"]
        except KeyError:
            pass
        return kwargs

    def build(self):
        d = self.prepare_missing_fields()
        return models.Actor(**d)

    def save(self, **kwargs):
        d = self.prepare_missing_fields()
        d.update(kwargs)
        return models.Actor.objects.update_or_create(url=d["url"], defaults=d)[0]

    def validate_summary(self, value):
        if value:
            return value[:500]


class APIActorSerializer(serializers.ModelSerializer):
    class Meta:
        model = models.Actor
        fields = [
            "id",
            "url",
            "creation_date",
            "summary",
            "preferred_username",
            "name",
            "last_fetch_date",
            "domain",
            "type",
            "manually_approves_followers",
        ]


class LibraryActorSerializer(ActorSerializer):
    url = serializers.ListField(child=serializers.JSONField())

    def validate(self, validated_data):
        try:
            urls = validated_data["url"]
        except KeyError:
            raise serializers.ValidationError("Missing URL field")

        for u in urls:
            try:
                if u["name"] != "library":
                    continue
                validated_data["library_url"] = u["href"]
                break
            except KeyError:
                continue

        return validated_data


class APIFollowSerializer(serializers.ModelSerializer):
    class Meta:
        model = models.Follow
        fields = [
            "uuid",
            "actor",
            "target",
            "approved",
            "creation_date",
            "modification_date",
        ]


class APILibrarySerializer(serializers.ModelSerializer):
    actor = APIActorSerializer()
    follow = APIFollowSerializer()

    class Meta:
        model = models.Library

        read_only_fields = [
            "actor",
            "uuid",
            "url",
            "tracks_count",
            "follow",
            "fetched_date",
            "modification_date",
            "creation_date",
        ]
        fields = [
            "autoimport",
            "federation_enabled",
            "download_files",
        ] + read_only_fields


class APILibraryScanSerializer(serializers.Serializer):
    until = serializers.DateTimeField(required=False)


class APILibraryFollowUpdateSerializer(serializers.Serializer):
    follow = serializers.IntegerField()
    approved = serializers.BooleanField()

    def validate_follow(self, value):
        from . import actors

        library_actor = actors.SYSTEM_ACTORS["library"].get_actor_instance()
        qs = models.Follow.objects.filter(pk=value, target=library_actor)
        try:
            return qs.get()
        except models.Follow.DoesNotExist:
            raise serializers.ValidationError("Invalid follow")

    def save(self):
        new_status = self.validated_data["approved"]
        follow = self.validated_data["follow"]
        if new_status == follow.approved:
            return follow

        follow.approved = new_status
        follow.save(update_fields=["approved", "modification_date"])
        if new_status:
            activity.accept_follow(follow)
        return follow


class APILibraryCreateSerializer(serializers.ModelSerializer):
    actor = serializers.URLField(max_length=500)
    federation_enabled = serializers.BooleanField()
    uuid = serializers.UUIDField(read_only=True)

    class Meta:
        model = models.Library
        fields = ["uuid", "actor", "autoimport", "federation_enabled", "download_files"]

    def validate(self, validated_data):
        from . import actors
        from . import library

        actor_url = validated_data["actor"]
        actor_data = actors.get_actor_data(actor_url)
        acs = LibraryActorSerializer(data=actor_data)
        acs.is_valid(raise_exception=True)
        try:
            actor = models.Actor.objects.get(url=actor_url)
        except models.Actor.DoesNotExist:
            actor = acs.save()
        library_actor = actors.SYSTEM_ACTORS["library"].get_actor_instance()
        validated_data["follow"] = models.Follow.objects.get_or_create(
            actor=library_actor, target=actor
        )[0]
        if validated_data["follow"].approved is None:
            funkwhale_utils.on_commit(
                activity.deliver,
                FollowSerializer(validated_data["follow"]).data,
                on_behalf_of=validated_data["follow"].actor,
                to=[validated_data["follow"].target.url],
            )

        library_data = library.get_library_data(acs.validated_data["library_url"])
        if "errors" in library_data:
            # we pass silently because it may means we require permission
            # before scanning
            pass
        validated_data["library"] = library_data
        validated_data["library"].setdefault("id", acs.validated_data["library_url"])
        validated_data["actor"] = actor
        return validated_data

    def create(self, validated_data):
        library = models.Library.objects.update_or_create(
            url=validated_data["library"]["id"],
            defaults={
                "actor": validated_data["actor"],
                "follow": validated_data["follow"],
                "tracks_count": validated_data["library"].get("totalItems"),
                "federation_enabled": validated_data["federation_enabled"],
                "autoimport": validated_data["autoimport"],
                "download_files": validated_data["download_files"],
            },
        )[0]
        return library


class APILibraryTrackSerializer(serializers.ModelSerializer):
    library = APILibrarySerializer()
    status = serializers.SerializerMethodField()

    class Meta:
        model = models.LibraryTrack
        fields = [
            "id",
            "url",
            "audio_url",
            "audio_mimetype",
            "creation_date",
            "modification_date",
            "fetched_date",
            "published_date",
            "metadata",
            "artist_name",
            "album_title",
            "title",
            "library",
            "local_track_file",
            "status",
        ]

    def get_status(self, o):
        try:
            if o.local_track_file is not None:
                return "imported"
        except music_models.TrackFile.DoesNotExist:
            pass
        for job in o.import_jobs.all():
            if job.status == "pending":
                return "import_pending"
        return "not_imported"


class FollowSerializer(serializers.Serializer):
    id = serializers.URLField(max_length=500)
    object = serializers.URLField(max_length=500)
    actor = serializers.URLField(max_length=500)
    type = serializers.ChoiceField(choices=["Follow"])

    def validate_object(self, v):
        expected = self.context.get("follow_target")
        if expected and expected.url != v:
            raise serializers.ValidationError("Invalid target")
        try:
            return models.Actor.objects.get(url=v)
        except models.Actor.DoesNotExist:
            raise serializers.ValidationError("Target not found")

    def validate_actor(self, v):
        expected = self.context.get("follow_actor")
        if expected and expected.url != v:
            raise serializers.ValidationError("Invalid actor")
        try:
            return models.Actor.objects.get(url=v)
        except models.Actor.DoesNotExist:
            raise serializers.ValidationError("Actor not found")

    def save(self, **kwargs):
        return models.Follow.objects.get_or_create(
            actor=self.validated_data["actor"],
            target=self.validated_data["object"],
            **kwargs,  # noqa
        )[0]

    def to_representation(self, instance):
        return {
            "@context": AP_CONTEXT,
            "actor": instance.actor.url,
            "id": instance.get_federation_url(),
            "object": instance.target.url,
            "type": "Follow",
        }


class APIFollowSerializer(serializers.ModelSerializer):
    actor = APIActorSerializer()
    target = APIActorSerializer()

    class Meta:
        model = models.Follow
        fields = [
            "uuid",
            "id",
            "approved",
            "creation_date",
            "modification_date",
            "actor",
            "target",
        ]


class AcceptFollowSerializer(serializers.Serializer):
    id = serializers.URLField(max_length=500)
    actor = serializers.URLField(max_length=500)
    object = FollowSerializer()
    type = serializers.ChoiceField(choices=["Accept"])

    def validate_actor(self, v):
        expected = self.context.get("follow_target")
        if expected and expected.url != v:
            raise serializers.ValidationError("Invalid actor")
        try:
            return models.Actor.objects.get(url=v)
        except models.Actor.DoesNotExist:
            raise serializers.ValidationError("Actor not found")

    def validate(self, validated_data):
        # we ensure the accept actor actually match the follow target
        if validated_data["actor"] != validated_data["object"]["object"]:
            raise serializers.ValidationError("Actor mismatch")
        try:
            validated_data["follow"] = (
                models.Follow.objects.filter(
                    target=validated_data["actor"],
                    actor=validated_data["object"]["actor"],
                )
                .exclude(approved=True)
                .get()
            )
        except models.Follow.DoesNotExist:
            raise serializers.ValidationError("No follow to accept")
        return validated_data

    def to_representation(self, instance):
        return {
            "@context": AP_CONTEXT,
            "id": instance.get_federation_url() + "/accept",
            "type": "Accept",
            "actor": instance.target.url,
            "object": FollowSerializer(instance).data,
        }

    def save(self):
        self.validated_data["follow"].approved = True
        self.validated_data["follow"].save()
        return self.validated_data["follow"]


class UndoFollowSerializer(serializers.Serializer):
    id = serializers.URLField(max_length=500)
    actor = serializers.URLField(max_length=500)
    object = FollowSerializer()
    type = serializers.ChoiceField(choices=["Undo"])

    def validate_actor(self, v):
        expected = self.context.get("follow_target")
        if expected and expected.url != v:
            raise serializers.ValidationError("Invalid actor")
        try:
            return models.Actor.objects.get(url=v)
        except models.Actor.DoesNotExist:
            raise serializers.ValidationError("Actor not found")

    def validate(self, validated_data):
        # we ensure the accept actor actually match the follow actor
        if validated_data["actor"] != validated_data["object"]["actor"]:
            raise serializers.ValidationError("Actor mismatch")
        try:
            validated_data["follow"] = models.Follow.objects.filter(
                actor=validated_data["actor"], target=validated_data["object"]["object"]
            ).get()
        except models.Follow.DoesNotExist:
            raise serializers.ValidationError("No follow to remove")
        return validated_data

    def to_representation(self, instance):
        return {
            "@context": AP_CONTEXT,
            "id": instance.get_federation_url() + "/undo",
            "type": "Undo",
            "actor": instance.actor.url,
            "object": FollowSerializer(instance).data,
        }

    def save(self):
        return self.validated_data["follow"].delete()


class ActorWebfingerSerializer(serializers.Serializer):
    subject = serializers.CharField()
    aliases = serializers.ListField(child=serializers.URLField(max_length=500))
    links = serializers.ListField()
    actor_url = serializers.URLField(max_length=500, required=False)

    def validate(self, validated_data):
        validated_data["actor_url"] = None
        for l in validated_data["links"]:
            try:
                if not l["rel"] == "self":
                    continue
                if not l["type"] == "application/activity+json":
                    continue
                validated_data["actor_url"] = l["href"]
                break
            except KeyError:
                pass
        if validated_data["actor_url"] is None:
            raise serializers.ValidationError("No valid actor url found")
        return validated_data

    def to_representation(self, instance):
        data = {}
        data["subject"] = "acct:{}".format(instance.webfinger_subject)
        data["links"] = [
            {"rel": "self", "href": instance.url, "type": "application/activity+json"}
        ]
        data["aliases"] = [instance.url]
        return data


class ActivitySerializer(serializers.Serializer):
    actor = serializers.URLField(max_length=500)
    id = serializers.URLField(max_length=500, required=False)
    type = serializers.ChoiceField(choices=[(c, c) for c in activity.ACTIVITY_TYPES])
    object = serializers.JSONField()

    def validate_object(self, value):
        try:
            type = value["type"]
        except KeyError:
            raise serializers.ValidationError("Missing object type")
        except TypeError:
            # probably a URL
            return value
        try:
            object_serializer = OBJECT_SERIALIZERS[type]
        except KeyError:
            raise serializers.ValidationError("Unsupported type {}".format(type))

        serializer = object_serializer(data=value)
        serializer.is_valid(raise_exception=True)
        return serializer.data

    def validate_actor(self, value):
        request_actor = self.context.get("actor")
        if request_actor and request_actor.url != value:
            raise serializers.ValidationError(
                "The actor making the request do not match" " the activity actor"
            )
        return value

    def to_representation(self, conf):
        d = {}
        d.update(conf)

        if self.context.get("include_ap_context", True):
            d["@context"] = AP_CONTEXT
        return d


class ObjectSerializer(serializers.Serializer):
    id = serializers.URLField(max_length=500)
    url = serializers.URLField(max_length=500, required=False, allow_null=True)
    type = serializers.ChoiceField(choices=[(c, c) for c in activity.OBJECT_TYPES])
    content = serializers.CharField(required=False, allow_null=True)
    summary = serializers.CharField(required=False, allow_null=True)
    name = serializers.CharField(required=False, allow_null=True)
    published = serializers.DateTimeField(required=False, allow_null=True)
    updated = serializers.DateTimeField(required=False, allow_null=True)
    to = serializers.ListField(
        child=serializers.URLField(max_length=500), required=False, allow_null=True
    )
    cc = serializers.ListField(
        child=serializers.URLField(max_length=500), required=False, allow_null=True
    )
    bto = serializers.ListField(
        child=serializers.URLField(max_length=500), required=False, allow_null=True
    )
    bcc = serializers.ListField(
        child=serializers.URLField(max_length=500), required=False, allow_null=True
    )


OBJECT_SERIALIZERS = {t: ObjectSerializer for t in activity.OBJECT_TYPES}


class PaginatedCollectionSerializer(serializers.Serializer):
    type = serializers.ChoiceField(choices=["Collection"])
    totalItems = serializers.IntegerField(min_value=0)
    actor = serializers.URLField(max_length=500)
    id = serializers.URLField(max_length=500)
    first = serializers.URLField(max_length=500)
    last = serializers.URLField(max_length=500)

    def to_representation(self, conf):
        paginator = Paginator(conf["items"], conf.get("page_size", 20))
        first = funkwhale_utils.set_query_parameter(conf["id"], page=1)
        current = first
        last = funkwhale_utils.set_query_parameter(conf["id"], page=paginator.num_pages)
        d = {
            "id": conf["id"],
            "actor": conf["actor"].url,
            "totalItems": paginator.count,
            "type": "Collection",
            "current": current,
            "first": first,
            "last": last,
        }
        if self.context.get("include_ap_context", True):
            d["@context"] = AP_CONTEXT
        return d


class CollectionPageSerializer(serializers.Serializer):
    type = serializers.ChoiceField(choices=["CollectionPage"])
    totalItems = serializers.IntegerField(min_value=0)
    items = serializers.ListField()
    actor = serializers.URLField(max_length=500)
    id = serializers.URLField(max_length=500)
    first = serializers.URLField(max_length=500)
    last = serializers.URLField(max_length=500)
    next = serializers.URLField(max_length=500, required=False)
    prev = serializers.URLField(max_length=500, required=False)
    partOf = serializers.URLField(max_length=500)

    def validate_items(self, v):
        item_serializer = self.context.get("item_serializer")
        if not item_serializer:
            return v
        raw_items = [item_serializer(data=i, context=self.context) for i in v]
        valid_items = []
        for i in raw_items:
            if i.is_valid():
                valid_items.append(i)
            else:
                logger.debug("Invalid item %s: %s", i.data, i.errors)

        return valid_items

    def to_representation(self, conf):
        page = conf["page"]
        first = funkwhale_utils.set_query_parameter(conf["id"], page=1)
        last = funkwhale_utils.set_query_parameter(
            conf["id"], page=page.paginator.num_pages
        )
        id = funkwhale_utils.set_query_parameter(conf["id"], page=page.number)
        d = {
            "id": id,
            "partOf": conf["id"],
            "actor": conf["actor"].url,
            "totalItems": page.paginator.count,
            "type": "CollectionPage",
            "first": first,
            "last": last,
            "items": [
                conf["item_serializer"](
                    i, context={"actor": conf["actor"], "include_ap_context": False}
                ).data
                for i in page.object_list
            ],
        }

        if page.has_previous():
            d["prev"] = funkwhale_utils.set_query_parameter(
                conf["id"], page=page.previous_page_number()
            )

        if page.has_next():
            d["next"] = funkwhale_utils.set_query_parameter(
                conf["id"], page=page.next_page_number()
            )

        if self.context.get("include_ap_context", True):
            d["@context"] = AP_CONTEXT
        return d


class ArtistMetadataSerializer(serializers.Serializer):
    musicbrainz_id = serializers.UUIDField(required=False, allow_null=True)
    name = serializers.CharField()


class ReleaseMetadataSerializer(serializers.Serializer):
    musicbrainz_id = serializers.UUIDField(required=False, allow_null=True)
    title = serializers.CharField()


class RecordingMetadataSerializer(serializers.Serializer):
    musicbrainz_id = serializers.UUIDField(required=False, allow_null=True)
    title = serializers.CharField()


class AudioMetadataSerializer(serializers.Serializer):
    artist = ArtistMetadataSerializer()
    release = ReleaseMetadataSerializer()
    recording = RecordingMetadataSerializer()
    bitrate = serializers.IntegerField(required=False, allow_null=True, min_value=0)
    size = serializers.IntegerField(required=False, allow_null=True, min_value=0)
    length = serializers.IntegerField(required=False, allow_null=True, min_value=0)


class AudioSerializer(serializers.Serializer):
    type = serializers.CharField()
    id = serializers.URLField(max_length=500)
    url = serializers.JSONField()
    published = serializers.DateTimeField()
    updated = serializers.DateTimeField(required=False)
    metadata = AudioMetadataSerializer()

    def validate_type(self, v):
        if v != "Audio":
            raise serializers.ValidationError("Invalid type for audio")
        return v

    def validate_url(self, v):
        try:
            v["href"]
        except (KeyError, TypeError):
            raise serializers.ValidationError("Missing href")

        try:
            media_type = v["mediaType"]
        except (KeyError, TypeError):
            raise serializers.ValidationError("Missing mediaType")

        if not media_type or not media_type.startswith("audio/"):
            raise serializers.ValidationError("Invalid mediaType")

        return v

    def create(self, validated_data):
        defaults = {
            "audio_mimetype": validated_data["url"]["mediaType"],
            "audio_url": validated_data["url"]["href"],
            "metadata": validated_data["metadata"],
            "artist_name": validated_data["metadata"]["artist"]["name"],
            "album_title": validated_data["metadata"]["release"]["title"],
            "title": validated_data["metadata"]["recording"]["title"],
            "published_date": validated_data["published"],
            "modification_date": validated_data.get("updated"),
        }
        return models.LibraryTrack.objects.get_or_create(
            library=self.context["library"], url=validated_data["id"], defaults=defaults
        )[0]

    def to_representation(self, instance):
        track = instance.track
        album = instance.track.album
        artist = instance.track.artist

        d = {
            "type": "Audio",
            "id": instance.get_federation_url(),
            "name": instance.track.full_name,
            "published": instance.creation_date.isoformat(),
            "updated": instance.modification_date.isoformat(),
            "metadata": {
                "artist": {
                    "musicbrainz_id": str(artist.mbid) if artist.mbid else None,
                    "name": artist.name,
                },
                "release": {
                    "musicbrainz_id": str(album.mbid) if album.mbid else None,
                    "title": album.title,
                },
                "recording": {
                    "musicbrainz_id": str(track.mbid) if track.mbid else None,
                    "title": track.title,
                },
                "bitrate": instance.bitrate,
                "size": instance.size,
                "length": instance.duration,
            },
            "url": {
                "href": utils.full_url(instance.path),
                "type": "Link",
                "mediaType": instance.mimetype,
            },
            "attributedTo": [self.context["actor"].url],
        }
        if self.context.get("include_ap_context", True):
            d["@context"] = AP_CONTEXT
        return d


class CollectionSerializer(serializers.Serializer):
    def to_representation(self, conf):
        d = {
            "id": conf["id"],
            "actor": conf["actor"].url,
            "totalItems": len(conf["items"]),
            "type": "Collection",
            "items": [
                conf["item_serializer"](
                    i, context={"actor": conf["actor"], "include_ap_context": False}
                ).data
                for i in conf["items"]
            ],
        }

        if self.context.get("include_ap_context", True):
            d["@context"] = AP_CONTEXT
        return d


class LibraryTrackActionSerializer(common_serializers.ActionSerializer):
    actions = [common_serializers.Action("import", allow_all=True)]
    filterset_class = filters.LibraryTrackFilter

    @transaction.atomic
    def handle_import(self, objects):
        batch = music_models.ImportBatch.objects.create(
            source="federation", submitted_by=self.context["submitted_by"]
        )
        jobs = []
        for lt in objects:
            job = music_models.ImportJob(
                batch=batch, library_track=lt, mbid=lt.mbid, source=lt.url
            )
            jobs.append(job)

        music_models.ImportJob.objects.bulk_create(jobs)
        music_tasks.import_batch_run.delay(import_batch_id=batch.pk)

        return {"batch": {"id": batch.pk}}