"""
project_vms — Registry der QEMU-VMs PRO PROJEKT.

Persistenz: /shared/config/project_vms.json  →  { project_id: [ {vm}, ... ] }.
Eine VM = {name, arch, iso, vnc_display, mem, created_at, updated_at}. Der echte
Start/Stop laeuft ueber `aria-vm` auf dem Host (SSH aria-wohnung, siehe main.py);
diese Datei haelt nur die Zuordnung VM ↔ Projekt + die Startparameter, damit die
Liste im Desktop-Panel der App pro Projekt erscheint (auch wenn leer).
"""

from __future__ import annotations

import json
import os
import re
import time
from pathlib import Path
from typing import Optional

VMS_FILE = Path(os.environ.get("PROJECT_VMS_FILE", "/shared/config/project_vms.json"))
NAME_RE = re.compile(r"^[a-zA-Z0-9_-]{1,40}$")
VALID_ARCH = {"x86_64", "amd64", "i386", "i686", "x86", "arm", "aarch64",
              "mips", "mipsel", "mips64", "ppc", "ppc64", "riscv64", "sparc"}


def _load() -> dict:
    if not VMS_FILE.exists():
        return {}
    try:
        data = json.loads(VMS_FILE.read_text(encoding="utf-8"))
        return data if isinstance(data, dict) else {}
    except Exception:
        return {}


def _save(data: dict) -> None:
    VMS_FILE.parent.mkdir(parents=True, exist_ok=True)
    tmp = VMS_FILE.with_suffix(".tmp")
    tmp.write_text(json.dumps(data, indent=2, ensure_ascii=False), encoding="utf-8")
    tmp.replace(VMS_FILE)


def list_vms(project_id: str) -> list[dict]:
    return _load().get(project_id or "", [])


def get_vm(project_id: str, name: str) -> Optional[dict]:
    for v in list_vms(project_id):
        if v.get("name") == name:
            return v
    return None


def add_vm(project_id: str, name: str, arch: str, iso: str = "",
           floppy: str = "", disk: str = "",
           vnc_display: int = 1, mem: int = 1024) -> dict:
    """Registriert/aktualisiert eine VM. Medien (disk/floppy/iso) sind optional —
    leer = aria-vm erkennt disk.qcow2/floppy.img/cdrom.iso im VM-Ordner selbst.
    ARIA setzt hier, was sie zum Task passend gebaut hat (Festplatte fuer DOS-
    Spiele, Diskette fuer OS-Dev, ISO fuer Installer)."""
    if not NAME_RE.match(name or ""):
        raise ValueError(f"Ungueltiger VM-Name: {name!r} (nur a-z0-9_-, max 40)")
    if arch not in VALID_ARCH:
        raise ValueError(f"Unbekannte Architektur: {arch!r}")
    data = _load()
    lst = data.setdefault(project_id or "", [])
    now = int(time.time())
    fields = {"arch": arch, "iso": iso, "floppy": floppy, "disk": disk,
              "vnc_display": int(vnc_display), "mem": int(mem), "updated_at": now}
    for v in lst:
        if v.get("name") == name:
            v.update(fields)
            _save(data)
            return v
    vm = {"name": name, "created_at": now, **fields}
    lst.append(vm)
    _save(data)
    return vm


def remove_vm(project_id: str, name: str) -> bool:
    data = _load()
    lst = data.get(project_id or "")
    if not lst:
        return False
    new = [v for v in lst if v.get("name") != name]
    if len(new) == len(lst):
        return False
    data[project_id or ""] = new
    _save(data)
    return True