"""Comments router with RBAC and notifications."""
from typing import List
from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session

from app.core.config import get_db
from app.models import models
from app.models.task import Task
from app.schemas import schemas
from app.api.deps import get_current_user_or_apikey
from app.api.rbac import check_project_role
from app.models.notification import Notification as NotificationModel

router = APIRouter(tags=["Comments"])


def _notify_if_needed(db, task_id, user_ids, ntype, title):
    """Helper to notify multiple users."""
    task = db.query(Task).filter(Task.id == task_id).first()
    if not task:
        return
    for uid in set(user_ids):
        if uid:
            n = NotificationModel(user_id=uid, type=ntype, title=title, entity_type="task", entity_id=task_id)
            db.add(n)
    db.commit()


@router.post("/comments", response_model=schemas.CommentResponse, status_code=status.HTTP_201_CREATED)
def create_comment(comment: schemas.CommentCreate, db: Session = Depends(get_db), current_user: models.User = Depends(get_current_user_or_apikey)):
    task = db.query(Task).filter(Task.id == comment.task_id).first()
    if not task:
        raise HTTPException(status_code=404, detail="Task not found")
    check_project_role(db, current_user.id, task.project_id, min_role="viewer")
    
    db_comment = models.Comment(**comment.model_dump())
    db.add(db_comment)
    db.commit()
    db.refresh(db_comment)
    
    # Notify reporter and assignee (but not the commenter themselves)
    notify_users = []
    if task.reporter_id != current_user.id:
        notify_users.append(task.reporter_id)
    if task.assignee_id and task.assignee_id != current_user.id:
        notify_users.append(task.assignee_id)
    if notify_users:
        _notify_if_needed(db, task.id, notify_users, "comment_added", f"New comment on: {task.title[:50]}")
    
    return db_comment


@router.get("/tasks/{task_id}/comments")
def list_comments(task_id: str, db: Session = Depends(get_db)):
    """List comments for a task. task_id can be numeric id or task_code."""
    try:
        tid = int(task_id)
    except (ValueError, TypeError):
        task = db.query(Task).filter(Task.task_code == task_id).first()
        if not task:
            raise HTTPException(status_code=404, detail="Task not found")
        tid = task.id
    comments = db.query(models.Comment).filter(models.Comment.task_id == tid).all()
    result = []
    for c in comments:
        author = db.query(models.User).filter(models.User.id == c.author_id).first()
        result.append({
            "id": c.id,
            "content": c.content,
            "task_id": c.task_id,
            "author_id": c.author_id,
            "author_username": author.username if author else None,
            "created_at": c.created_at,
            "updated_at": c.updated_at,
        })
    return result


@router.patch("/comments/{comment_id}", response_model=schemas.CommentResponse)
def update_comment(comment_id: int, comment_update: schemas.CommentUpdate, db: Session = Depends(get_db), current_user: models.User = Depends(get_current_user_or_apikey)):
    comment = db.query(models.Comment).filter(models.Comment.id == comment_id).first()
    if not comment:
        raise HTTPException(status_code=404, detail="Comment not found")
    task = db.query(Task).filter(Task.id == comment.task_id).first()
    if not task:
        raise HTTPException(status_code=404, detail="Task not found")
    check_project_role(db, current_user.id, task.project_id, min_role="viewer")
    for field, value in comment_update.model_dump(exclude_unset=True).items():
        setattr(comment, field, value)
    db.commit()
    db.refresh(comment)
    return comment


@router.delete("/comments/{comment_id}", status_code=status.HTTP_204_NO_CONTENT)
def delete_comment(comment_id: int, db: Session = Depends(get_db), current_user: models.User = Depends(get_current_user_or_apikey)):
    comment = db.query(models.Comment).filter(models.Comment.id == comment_id).first()
    if not comment:
        raise HTTPException(status_code=404, detail="Comment not found")
    task = db.query(Task).filter(Task.id == comment.task_id).first()
    if not task:
        raise HTTPException(status_code=404, detail="Task not found")
    check_project_role(db, current_user.id, task.project_id, min_role="dev")
    db.delete(comment)
    db.commit()
    return None