from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session
from sqlalchemy import func
from typing import List
from app.db.base import get_db
from app.core.deps import get_current_user
from app.models.user import User
from app.models.list import List as ContactList, ListMember
from app.models.contact import Contact
from app.schemas.list import (
    ListCreate, ListUpdate, ListResponse,
    ListMemberAdd, ListMemberRemove
)

router = APIRouter()

@router.post("", response_model=ListResponse, status_code=status.HTTP_201_CREATED)
def create_list(
    list_data: ListCreate,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    db_list = ContactList(
        user_id=current_user.id,
        name=list_data.name
    )
    db.add(db_list)
    db.commit()
    db.refresh(db_list)
    
    db_list.member_count = 0
    return db_list

@router.get("", response_model=List[ListResponse])
def list_lists(
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    lists = db.query(ContactList).filter(ContactList.user_id == current_user.id).all()
    
    # Add member counts
    for lst in lists:
        count = db.query(func.count(ListMember.id)).filter(
            ListMember.list_id == lst.id
        ).scalar()
        lst.member_count = count or 0
    
    return lists

@router.get("/{list_id}", response_model=ListResponse)
def get_list(
    list_id: int,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    lst = db.query(ContactList).filter(
        ContactList.id == list_id,
        ContactList.user_id == current_user.id
    ).first()
    
    if not lst:
        raise HTTPException(status_code=404, detail="List not found")
    
    count = db.query(func.count(ListMember.id)).filter(
        ListMember.list_id == lst.id
    ).scalar()
    lst.member_count = count or 0
    
    return lst

@router.put("/{list_id}", response_model=ListResponse)
def update_list(
    list_id: int,
    list_update: ListUpdate,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    lst = db.query(ContactList).filter(
        ContactList.id == list_id,
        ContactList.user_id == current_user.id
    ).first()
    
    if not lst:
        raise HTTPException(status_code=404, detail="List not found")
    
    lst.name = list_update.name
    db.commit()
    db.refresh(lst)
    
    count = db.query(func.count(ListMember.id)).filter(
        ListMember.list_id == lst.id
    ).scalar()
    lst.member_count = count or 0
    
    return lst

@router.delete("/{list_id}", status_code=status.HTTP_204_NO_CONTENT)
def delete_list(
    list_id: int,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    lst = db.query(ContactList).filter(
        ContactList.id == list_id,
        ContactList.user_id == current_user.id
    ).first()
    
    if not lst:
        raise HTTPException(status_code=404, detail="List not found")
    
    db.delete(lst)
    db.commit()
    
    return None

@router.post("/{list_id}/members", status_code=status.HTTP_204_NO_CONTENT)
def add_members(
    list_id: int,
    members: ListMemberAdd,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    lst = db.query(ContactList).filter(
        ContactList.id == list_id,
        ContactList.user_id == current_user.id
    ).first()
    
    if not lst:
        raise HTTPException(status_code=404, detail="List not found")
    
    # Verify all contacts belong to user
    contacts = db.query(Contact).filter(
        Contact.id.in_(members.contact_ids),
        Contact.user_id == current_user.id
    ).all()
    
    if len(contacts) != len(members.contact_ids):
        raise HTTPException(status_code=400, detail="Some contacts not found")
    
    # Add members (skip duplicates)
    for contact_id in members.contact_ids:
        existing = db.query(ListMember).filter(
            ListMember.list_id == list_id,
            ListMember.contact_id == contact_id
        ).first()
        
        if not existing:
            member = ListMember(list_id=list_id, contact_id=contact_id)
            db.add(member)
    
    db.commit()
    return None

@router.delete("/{list_id}/members", status_code=status.HTTP_204_NO_CONTENT)
def remove_members(
    list_id: int,
    members: ListMemberRemove,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    lst = db.query(ContactList).filter(
        ContactList.id == list_id,
        ContactList.user_id == current_user.id
    ).first()
    
    if not lst:
        raise HTTPException(status_code=404, detail="List not found")
    
    db.query(ListMember).filter(
        ListMember.list_id == list_id,
        ListMember.contact_id.in_(members.contact_ids)
    ).delete(synchronize_session=False)
    
    db.commit()
    return None

@router.get("/{list_id}/contacts", response_model=List[dict])
def get_list_contacts(
    list_id: int,
    current_user: User = Depends(get_current_user),
    db: Session = Depends(get_db)
):
    lst = db.query(ContactList).filter(
        ContactList.id == list_id,
        ContactList.user_id == current_user.id
    ).first()
    
    if not lst:
        raise HTTPException(status_code=404, detail="List not found")
    
    members = db.query(Contact).join(ListMember).filter(
        ListMember.list_id == list_id
    ).all()
    
    return [
        {
            "id": c.id,
            "phone_e164": c.phone_e164,
            "first_name": c.first_name,
            "last_name": c.last_name,
            "email": c.email,
            "opted_in": c.opted_in
        }
        for c in members
    ]