"""Desktop session — persistent state + terminal management."""

import logging

from fastapi import APIRouter, Depends, HTTPException, Request, Query
from pydantic import BaseModel

from backend.auth import get_current_user, decode_token
from backend.sessions import manager

router = APIRouter(prefix="/api/session", tags=["session"])
log = logging.getLogger("atlus.session")


# ---------------------------------------------------------------------------
# Models
# ---------------------------------------------------------------------------

class DesktopState(BaseModel):
    open_apps: list[str] = []
    active_app: str | None = None
    terminal_tabs: list[dict] = []  # [{terminal_id, title}]


class TerminalCreate(BaseModel):
    cols: int = 120
    rows: int = 30


# ---------------------------------------------------------------------------
# Session endpoints
# ---------------------------------------------------------------------------

@router.get("")
async def get_session(user: str = Depends(get_current_user)):
    """Get or create the user's desktop session."""
    session = manager.get_or_create(user)
    return session.to_dict()


@router.put("/state")
async def save_state(
    state: DesktopState,
    request: Request,
    token: str = Query(default=None),
    user: str = Depends(get_current_user),
):
    """Save desktop state (open apps, active app, terminal tab info)."""
    manager.save_state(user, state.model_dump())
    return {"ok": True}


@router.post("/state")
async def save_state_beacon(
    request: Request,
    token: str = Query(default=None),
):
    """Save desktop state via sendBeacon (POST with token in query param)."""
    if not token:
        raise HTTPException(401, "Missing token")
    try:
        payload = decode_token(token)
    except Exception:
        raise HTTPException(401, "Invalid token")
    user = payload["sub"]
    body = await request.json()
    state = DesktopState(**body)
    manager.save_state(user, state.model_dump())
    return {"ok": True}


# ---------------------------------------------------------------------------
# Terminal endpoints
# ---------------------------------------------------------------------------

@router.get("/terminals")
async def list_terminals(user: str = Depends(get_current_user)):
    """List all alive terminals for the user."""
    return manager.list_terminals(user)


@router.post("/terminals")
async def create_terminal(
    req: TerminalCreate,
    user: str = Depends(get_current_user),
):
    """Create a new persistent terminal."""
    try:
        terminal = manager.create_terminal(user, cols=req.cols, rows=req.rows)
    except Exception as e:
        log.exception("Failed to create terminal for %s", user)
        raise HTTPException(500, f"Failed to spawn terminal: {e}")
    return terminal.to_dict()


@router.delete("/terminals/{terminal_id}")
async def close_terminal(
    terminal_id: str,
    user: str = Depends(get_current_user),
):
    """Close and kill a terminal."""
    if not manager.close_terminal(user, terminal_id):
        raise HTTPException(404, "Terminal not found")
    return {"ok": True}