"""Operator → cart persistence for chat-saiden.

A 'cart' here is the per-operator calibrated config: persona name, voice,
system prompt, UI palette. Stored as JSON on disk under
~/.local/share/chat-saiden/operators/<email>.json.

Later this can be promoted to a real `marauder cart` once the format
stabilises.
"""

from __future__ import annotations

import json
import logging
import os
import re
from dataclasses import asdict, dataclass, field
from datetime import datetime
from pathlib import Path

log = logging.getLogger("chat-saiden.cart")

DATA_DIR = Path(
    os.environ.get("CHAT_SAIDEN_DATA_DIR")
    or (Path.home() / ".local/share/chat-saiden")
)
OPERATORS_DIR = DATA_DIR / "operators"


@dataclass
class Cart:
    operator_email: str
    operator_name: str = ""
    persona_name: str = "Samantha"
    cart_tag: str = ""               # marauder cart tag — links to ~/.marauder cart DB
    language: str = "en"             # en | pl
    voice: str = "en_US-amy-medium"
    system_prompt: str = ""
    # UI calibration outputs. All default to neutral.
    ui_palette: str = "default"       # default | rose | morning | evening | sage | paper | ink
    ui_typography: str = "sans"       # sans | serif-warm | serif-formal | mixed-modern | mono
    ui_density: str = "normal"        # airy | normal | dense
    ui_labels: str = "block"          # block | cursive | none | prefix
    created_at: str = ""
    version: int = 3

    @property
    def is_calibrated(self) -> bool:
        return bool(self.system_prompt and self.persona_name and self.voice)


def _slug(email: str) -> str:
    return re.sub(r"[^a-z0-9._-]", "_", email.lower())


def _path(email: str) -> Path:
    OPERATORS_DIR.mkdir(parents=True, exist_ok=True)
    return OPERATORS_DIR / f"{_slug(email)}.json"


def load(email: str) -> Cart | None:
    p = _path(email)
    if not p.exists():
        return None
    try:
        data = json.loads(p.read_text(encoding="utf-8"))
        # tolerate older carts missing the new ui_* fields
        return Cart(**{k: v for k, v in data.items() if k in Cart.__dataclass_fields__})
    except Exception:
        log.exception("failed to load cart for %s", email)
        return None


def save(cart: Cart) -> None:
    if not cart.created_at:
        cart.created_at = datetime.utcnow().isoformat(timespec="seconds") + "Z"
    p = _path(cart.operator_email)
    p.write_text(json.dumps(asdict(cart), indent=2), encoding="utf-8")
    log.info("saved cart for %s → %s", cart.operator_email, p)


def forget(email: str) -> bool:
    p = _path(email)
    if p.exists():
        p.unlink()
        log.info("forgot cart for %s", email)
        return True
    return False