Hulumath-Web/backend/content/views.py

from django.db.models import Count
from django.shortcuts import get_object_or_404
from rest_framework import permissions, status
from rest_framework.response import Response
from rest_framework.views import APIView

from .models import ContentInteraction, ContentItem, VideoProgress
from .services import complete_video

ABILITY_META = {
    ContentItem.Ability.VISION: {"label": "数学眼光", "icon": "◉", "color": "#5d73e8"},
    ContentItem.Ability.HUMANITIES: {"label": "数学人文", "icon": "▤", "color": "#b76d38"},
    ContentItem.Ability.DETECTION: {"label": "数学侦探", "icon": "⌕", "color": "#287f78"},
    ContentItem.Ability.MODELING: {"label": "数学建模", "icon": "⌁", "color": "#d98628"},
    ContentItem.Ability.CONNECTION: {"label": "数学联结", "icon": "⛓", "color": "#8667b5"},
}


def serialize_item(item, progress=None):
    return {
        "slug": item.slug,
        "title": item.title,
        "kind": item.kind,
        "summary": item.summary,
        "body": item.body,
        "cover_url": item.cover_url,
        "media_url": item.media_url,
        "topics": item.topics,
        "source": item.source,
        "ability_dimension": item.ability_dimension,
        "ability": ABILITY_META.get(item.ability_dimension),
        "module": item.module,
        "sub_category": item.sub_category,
        "discipline": item.discipline,
        "discipline_icon": item.discipline_icon,
        "author": item.author,
        "duration_seconds": item.duration_seconds,
        "view_count": item.view_count,
        "comment_count": item.comment_count,
        "published_at": item.published_at,
        "progress": (
            {
                "position_seconds": progress.position_seconds,
                "completed": progress.completed,
                "reward_granted": progress.reward_granted,
            }
            if progress
            else None
        ),
    }


class ContentListView(APIView):
    permission_classes = [permissions.AllowAny]

    def get(self, request):
        queryset = ContentItem.objects.filter(is_published=True)
        kind = request.query_params.get("kind")
        ability = request.query_params.get("ability")
        discipline = request.query_params.get("discipline")
        if kind:
            queryset = queryset.filter(kind=kind)
        if ability:
            queryset = queryset.filter(ability_dimension=ability)
        if discipline:
            queryset = queryset.filter(discipline=discipline)

        progress_by_content = {}
        if request.user.is_authenticated:
            progress_by_content = {
                item.content_id: item
                for item in VideoProgress.objects.filter(
                    user=request.user,
                    content__in=queryset,
                )
            }
        return Response(
            [
                serialize_item(item, progress_by_content.get(item.id))
                for item in queryset[:100]
            ]
        )


class VideoCatalogView(APIView):
    permission_classes = [permissions.AllowAny]

    def get(self, request):
        videos = ContentItem.objects.filter(
            kind=ContentItem.Kind.VIDEO,
            is_published=True,
        )
        counts = {
            row["ability_dimension"]: row["count"]
            for row in videos.values("ability_dimension").annotate(count=Count("id"))
        }
        abilities = [
            {
                "id": ability,
                **meta,
                "count": counts.get(ability, 0),
            }
            for ability, meta in ABILITY_META.items()
        ]
        disciplines = [
            {
                "name": row["discipline"],
                "icon": row["discipline_icon"],
                "count": row["count"],
            }
            for row in videos.values("discipline", "discipline_icon")
            .annotate(count=Count("id"))
            .order_by("discipline")
        ]
        return Response(
            {
                "total": videos.count(),
                "abilities": abilities,
                "disciplines": disciplines,
            }
        )


class ContentDetailView(APIView):
    permission_classes = [permissions.AllowAny]

    def get(self, request, slug):
        item = get_object_or_404(ContentItem, slug=slug, is_published=True)
        progress = None
        if request.user.is_authenticated:
            ContentInteraction.objects.get_or_create(
                user=request.user,
                content=item,
                action=ContentInteraction.Action.VIEW,
            )
            progress, _ = VideoProgress.objects.get_or_create(
                user=request.user,
                content=item,
            )
        return Response(serialize_item(item, progress))


class VideoCompleteView(APIView):
    def post(self, request, slug):
        item = get_object_or_404(
            ContentItem,
            slug=slug,
            kind=ContentItem.Kind.VIDEO,
            is_published=True,
        )
        progress, reward = complete_video(request.user, item)
        return Response(
            {
                "completed": progress.completed,
                "reward_granted": progress.reward_granted,
                "reward": reward,
            }
        )


class FavoriteView(APIView):
    def post(self, request, slug):
        item = get_object_or_404(ContentItem, slug=slug, is_published=True)
        _, created = ContentInteraction.objects.get_or_create(
            user=request.user,
            content=item,
            action=ContentInteraction.Action.FAVORITE,
        )
        return Response(
            {"favorite": True},
            status=status.HTTP_201_CREATED if created else status.HTTP_200_OK,
        )

    def delete(self, request, slug):
        ContentInteraction.objects.filter(
            user=request.user,
            content__slug=slug,
            action=ContentInteraction.Action.FAVORITE,
        ).delete()
        return Response(status=status.HTTP_204_NO_CONTENT)