from typing import List

from fastapi import APIRouter, Depends, HTTPException  # type: ignore
from sqlmodel import Session, select  # type: ignore

from app.database import get_session
from app.models import (
    Folder,
    FolderCreate,
    FolderTreeNode,
    FolderTreeResponse,
    Note,
    NoteRead,
)

router = APIRouter(prefix="/folders", tags=["folders"])


def build_folder_tree_node(folder: Folder) -> FolderTreeNode:
    """Recursively build a folder tree node with notes and children"""
    return FolderTreeNode(
        id=folder.id,
        name=folder.name,
        notes=[NoteRead.model_validate(note) for note in folder.notes],
        children=[build_folder_tree_node(child) for child in folder.children],
    )


@router.get("/tree", response_model=FolderTreeResponse)
def get_folder_tree(session: Session = Depends(get_session)):
    """Get complete folder tree with notes"""

    # Get all top-level folders (parent_id is None)
    top_level_folders = session.exec(
        select(Folder).where(Folder.parent_id == None)
    ).all()

    # Get all orphaned notes (folder_id is None)
    orphaned_notes = session.exec(select(Note).where(Note.folder_id == None)).all()

    # Build tree recursively
    tree = [build_folder_tree_node(folder) for folder in top_level_folders]

    return FolderTreeResponse(
        folders=tree,
        orphaned_notes=[NoteRead.model_validate(note) for note in orphaned_notes],
    )


@router.get("/", response_model=List[Folder])
def list_folders(session: Session = Depends(get_session)):
    """Get flat list of all folders"""
    folders = session.exec(select(Folder)).all()
    return folders


@router.post("/", response_model=Folder)
def create_folder(folder: FolderCreate, session: Session = Depends(get_session)):
    """Create a new folder"""
    db_folder = Folder.model_validate(folder)
    session.add(db_folder)
    session.commit()
    session.refresh(db_folder)
    return db_folder


@router.delete("/{folder_id}")
def delete_folder(folder_id: int, session: Session = Depends(get_session)):
    """Delete a folder"""
    folder = session.get(Folder, folder_id)
    if not folder:
        raise HTTPException(status_code=404, detail="Folder not found")

    session.delete(folder)
    session.commit()
    return {"message": "Folder deleted"}