"""用户主页和关注系统路由"""
from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.orm import Session
from sqlalchemy import func
from database import get_db
from models.user import User
from models.post import Post
from models.follow import Follow
from models.like import Collect
from models.notification import Notification
from routers.auth import get_current_user

router = APIRouter()


@router.get("/{user_id}")
def get_user_profile(
    user_id: int,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """获取用户主页信息"""
    user = db.query(User).filter(User.id == user_id).first()
    if not user:
        raise HTTPException(status_code=404, detail="用户不存在")

    post_count = db.query(func.count(Post.id)).filter(Post.user_id == user_id, Post.is_public == True).scalar()
    follower_count = db.query(func.count(Follow.id)).filter(Follow.following_id == user_id).scalar()
    following_count = db.query(func.count(Follow.id)).filter(Follow.follower_id == user_id).scalar()
    is_following = db.query(Follow).filter(
        Follow.follower_id == current_user.id, Follow.following_id == user_id
    ).first() is not None

    return {
        "id": user.id,
        "username": user.username,
        "email": user.email,
        "avatar": user.avatar,
        "created_at": user.created_at,
        "post_count": post_count,
        "follower_count": follower_count,
        "following_count": following_count,
        "is_following": is_following,
        "is_self": current_user.id == user_id,
    }


@router.post("/{user_id}/follow")
def toggle_follow(
    user_id: int,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """关注/取消关注"""
    if current_user.id == user_id:
        raise HTTPException(status_code=400, detail="不能关注自己")

    target = db.query(User).filter(User.id == user_id).first()
    if not target:
        raise HTTPException(status_code=404, detail="用户不存在")

    existing = db.query(Follow).filter(
        Follow.follower_id == current_user.id, Follow.following_id == user_id
    ).first()

    if existing:
        db.delete(existing)
        db.commit()
        return {"followed": False}
    else:
        follow = Follow(follower_id=current_user.id, following_id=user_id)
        db.add(follow)
        # 创建通知
        notif = Notification(
            user_id=user_id,
            type="follow",
            content=f"{current_user.username} 关注了你",
            from_user_id=current_user.id,
            related_id=current_user.id,
        )
        db.add(notif)
        db.commit()
        return {"followed": True}


@router.get("/{user_id}/posts")
def get_user_posts(
    user_id: int,
    page: int = 1,
    page_size: int = 20,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """获取用户的帖子列表"""
    query = db.query(Post).filter(Post.user_id == user_id)
    if user_id != current_user.id:
        query = query.filter(Post.is_public == True)
    posts = query.order_by(Post.created_at.desc()).offset((page - 1) * page_size).limit(page_size).all()

    user = db.query(User).filter(User.id == user_id).first()
    username = user.username if user else "未知"
    avatar = user.avatar if user else ""

    return [
        {
            "id": p.id, "title": p.title, "content": p.content[:200],
            "category": p.category, "tags": p.tags,
            "view_count": p.view_count, "like_count": p.like_count,
            "comment_count": p.comment_count, "collect_count": p.collect_count,
            "created_at": p.created_at, "updated_at": p.updated_at,
            "author": {"id": user_id, "username": username, "avatar": avatar},
        }
        for p in posts
    ]


@router.get("/{user_id}/followers")
def get_followers(
    user_id: int,
    page: int = 1,
    page_size: int = 20,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """获取粉丝列表"""
    follows = (
        db.query(Follow)
        .filter(Follow.following_id == user_id)
        .order_by(Follow.created_at.desc())
        .offset((page - 1) * page_size).limit(page_size).all()
    )
    user_ids = [f.follower_id for f in follows]
    users = db.query(User).filter(User.id.in_(user_ids)).all() if user_ids else []
    user_map = {u.id: u for u in users}

    return [
        {
            "id": uid,
            "username": user_map[uid].username if uid in user_map else "",
            "avatar": user_map[uid].avatar if uid in user_map else "",
        }
        for uid in user_ids
    ]


@router.get("/{user_id}/following")
def get_following(
    user_id: int,
    page: int = 1,
    page_size: int = 20,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """获取关注列表"""
    follows = (
        db.query(Follow)
        .filter(Follow.follower_id == user_id)
        .order_by(Follow.created_at.desc())
        .offset((page - 1) * page_size).limit(page_size).all()
    )
    user_ids = [f.following_id for f in follows]
    users = db.query(User).filter(User.id.in_(user_ids)).all() if user_ids else []
    user_map = {u.id: u for u in users}

    return [
        {
            "id": uid,
            "username": user_map[uid].username if uid in user_map else "",
            "avatar": user_map[uid].avatar if uid in user_map else "",
        }
        for uid in user_ids
    ]


@router.get("/{user_id}/collects")
def get_user_collects(
    user_id: int,
    page: int = 1,
    page_size: int = 20,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db),
):
    """获取用户收藏的帖子"""
    collects = (
        db.query(Collect)
        .filter(Collect.user_id == user_id)
        .order_by(Collect.created_at.desc())
        .offset((page - 1) * page_size).limit(page_size).all()
    )
    post_ids = [c.post_id for c in collects]
    if not post_ids:
        return []

    posts = db.query(Post).filter(Post.id.in_(post_ids)).all()
    post_map = {p.id: p for p in posts}
    author_ids = list(set(p.user_id for p in posts))
    authors = db.query(User).filter(User.id.in_(author_ids)).all()
    author_map = {a.id: a for a in authors}

    result = []
    for pid in post_ids:
        p = post_map.get(pid)
        if not p:
            continue
        a = author_map.get(p.user_id)
        result.append({
            "id": p.id, "title": p.title, "content": p.content[:200],
            "category": p.category, "tags": p.tags,
            "view_count": p.view_count, "like_count": p.like_count,
            "comment_count": p.comment_count, "collect_count": p.collect_count,
            "created_at": p.created_at,
            "author": {"id": p.user_id, "username": a.username if a else "", "avatar": a.avatar if a else ""},
        })
    return result