import uuid
from datetime import date
from typing import Optional
from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select
from app.database import get_db
from app.middleware.auth import get_current_user, require_any_role
from app.models.daily_note import DailyNote
from app.models.user import User
from app.schemas.daily_note import DailyNoteCreate, DailyNoteUpdate, DailyNoteOut
from app.utils.timezone import today_cst, parse_date
from app.utils.edit_log import compute_diff, append_entry, init_entry

router = APIRouter(prefix="/daily-notes", tags=["DailyNotes"])


async def _enrich(note: DailyNote, db: AsyncSession) -> dict:
    mgr = await db.execute(select(User.name).where(User.id == note.manager_id))
    return {
        "id": note.id, "manager_id": note.manager_id,
        "note_date": note.note_date, "category": note.category,
        "content": note.content, "time_range": note.time_range,
        "edit_log": note.edit_log or [], "created_at": note.created_at,
        "updated_at": note.updated_at, "manager_name": mgr.scalar_one_or_none(),
    }


@router.get("/")
async def list_notes(
    date_from: Optional[str] = Query(None),
    date_to: Optional[str] = Query(None),
    current_user: dict = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    query = select(DailyNote)
    if current_user["role"] == "manager":
        query = query.where(DailyNote.manager_id == uuid.UUID(current_user["user_id"]))
    if date_from:
        query = query.where(DailyNote.note_date >= parse_date(date_from))
    if date_to:
        query = query.where(DailyNote.note_date <= parse_date(date_to))
    query = query.order_by(DailyNote.note_date.desc(), DailyNote.created_at.desc()).limit(100)
    result = await db.execute(query)
    return [await _enrich(n, db) for n in result.scalars().all()]


@router.get("/today")
async def list_today_notes(
    current_user: dict = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    query = select(DailyNote).where(DailyNote.note_date == today_cst())
    if current_user["role"] == "manager":
        query = query.where(DailyNote.manager_id == uuid.UUID(current_user["user_id"]))
    result = await db.execute(query)
    notes = [await _enrich(n, db) for n in result.scalars().all()]
    return {"count": len(notes), "notes": notes}


@router.get("/{note_id}")
async def get_note(
    note_id: str,
    current_user: dict = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(select(DailyNote).where(DailyNote.id == note_id))
    note = result.scalar_one_or_none()
    if not note:
        raise HTTPException(status_code=404, detail="Not found")
    if current_user["role"] == "manager" and str(note.manager_id) != current_user["user_id"]:
        raise HTTPException(status_code=403, detail="Access denied")
    return await _enrich(note, db)


@router.post("/")
async def create_note(
    data: DailyNoteCreate,
    current_user: dict = Depends(require_any_role),
    db: AsyncSession = Depends(get_db),
):
    note = DailyNote(
        manager_id=uuid.UUID(current_user["user_id"]),
        note_date=parse_date(data.note_date),
        category=data.category,
        content=data.content,
        time_range=data.time_range,
    )
    init_entry(note, current_user["name"])
    db.add(note)
    await db.commit()
    await db.refresh(note)
    return await _enrich(note, db)


@router.put("/{note_id}")
async def update_note(
    note_id: str, data: DailyNoteUpdate,
    current_user: dict = Depends(require_any_role),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(select(DailyNote).where(DailyNote.id == note_id))
    note = result.scalar_one_or_none()
    if not note:
        raise HTTPException(status_code=404, detail="Not found")
    if current_user["role"] == "manager" and str(note.manager_id) != current_user["user_id"]:
        raise HTTPException(status_code=403, detail="Access denied")

    old_snapshot = {"note_date": str(note.note_date), "category": note.category, "content": note.content, "time_range": note.time_range}
    update_data = data.model_dump(exclude_unset=True)
    if "note_date" in update_data and update_data["note_date"]:
        update_data["note_date"] = parse_date(update_data["note_date"])
    for k, v in update_data.items():
        setattr(note, k, v)
    new_snapshot = {"note_date": str(note.note_date), "category": note.category, "content": note.content, "time_range": note.time_range}
    changes = compute_diff(old_snapshot, new_snapshot)
    if changes:
        append_entry(note, current_user["name"], changes, getattr(data, "edit_reason", None))
    await db.commit()
    await db.refresh(note)
    return await _enrich(note, db)


@router.delete("/{note_id}")
async def delete_note(
    note_id: str,
    current_user: dict = Depends(require_any_role),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(select(DailyNote).where(DailyNote.id == note_id))
    note = result.scalar_one_or_none()
    if not note:
        raise HTTPException(status_code=404, detail="Not found")
    if current_user["role"] == "manager" and str(note.manager_id) != current_user["user_id"]:
        raise HTTPException(status_code=403, detail="Access denied")
    await db.delete(note)
    await db.commit()
    return {"detail": "deleted"}