from __future__ import annotations
from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.orm import Session
from sqlalchemy import func as sqlfunc

from app.database import get_db
from app.auth import get_current_user
from app.models.blog import Blog
from app.schemas.blog import BlogSchema, BlogResponse, BlogListResponse

router = APIRouter(prefix="/api/blog", tags=["博客文章"], dependencies=[Depends(get_current_user)])


@router.get("/", response_model=BlogListResponse)
def list_blogs(
    page: int = Query(1, ge=1),
    page_size: int = Query(20, ge=1, le=100),
    keyword: str = Query("", description="搜索关键词"),
    db: Session = Depends(get_db),
):
    query = db.query(Blog)
    if keyword:
        query = query.filter(Blog.title.contains(keyword) | Blog.summary.contains(keyword))
    total = query.count()
    items = query.order_by(Blog.sort_order, Blog.id.desc()).offset((page - 1) * page_size).limit(page_size).all()
    return BlogListResponse(
        items=[BlogResponse.model_validate(b) for b in items],
        total=total,
    )


@router.post("/", response_model=BlogResponse, status_code=201)
def create_blog(req: BlogSchema, db: Session = Depends(get_db)):
    if db.query(Blog).filter(Blog.slug == req.slug).first():
        raise HTTPException(status_code=400, detail="该 slug 已存在")
    max_order = db.query(sqlfunc.max(Blog.sort_order)).scalar() or 0
    blog = Blog(**req.model_dump(), sort_order=max_order + 1)
    db.add(blog)
    db.commit()
    db.refresh(blog)
    return BlogResponse.model_validate(blog)


@router.put("/{blog_id}", response_model=BlogResponse)
def update_blog(blog_id: int, req: BlogSchema, db: Session = Depends(get_db)):
    blog = db.query(Blog).get(blog_id)
    if not blog:
        raise HTTPException(status_code=404, detail="文章不存在")
    existing = db.query(Blog).filter(Blog.slug == req.slug, Blog.id != blog_id).first()
    if existing:
        raise HTTPException(status_code=400, detail="该 slug 已被其他文章使用")
    for key, val in req.model_dump().items():
        setattr(blog, key, val)
    db.commit()
    db.refresh(blog)
    return BlogResponse.model_validate(blog)


@router.delete("/{blog_id}")
def delete_blog(blog_id: int, db: Session = Depends(get_db)):
    blog = db.query(Blog).get(blog_id)
    if not blog:
        raise HTTPException(status_code=404, detail="文章不存在")
    db.delete(blog)
    db.commit()
    return {"message": "删除成功"}


@router.put("/reorder/batch")
def reorder_blogs(ids: list[int], db: Session = Depends(get_db)):
    for i, bid in enumerate(ids):
        db.query(Blog).filter(Blog.id == bid).update({"sort_order": i})
    db.commit()
    return {"message": "排序更新成功"}