"""Local label history store.

Since the Stamps SERA API has no list-labels endpoint, we persist every
created label to appdata/label_history.json at print time. The history
window reads from here rather than polling the API.

The void/refund and SCAN form actions DO hit the API, using the label_id
stored here.
"""

from __future__ import annotations

import json
import logging
from dataclasses import asdict, dataclass
from datetime import datetime
from pathlib import Path

log = logging.getLogger(__name__)


@dataclass
class LabelEntry:
    label_id:        str
    tracking_number: str
    date_printed:    str        # ISO 8601
    recipient:       str        # name / first line of address block
    service:         str        # display name, e.g. "Ground Advantage"
    package_type:    str
    amount:          float | None
    notes:           str        # invoice numbers / free-text notes
    address_block:   str
    voided:          bool       = False
    shipment_status: str        = ""
    date_delivered:  str | None = None
    carrier:         str        = ""   # "usps" | "fedex"

    @property
    def date_printed_display(self) -> str:
        try:
            return datetime.fromisoformat(self.date_printed).strftime("%m/%d/%Y")
        except Exception:
            return self.date_printed

    @property
    def date_delivered_display(self) -> str:
        if not self.date_delivered:
            return ""
        try:
            return datetime.fromisoformat(self.date_delivered).strftime("%m/%d/%Y")
        except Exception:
            return self.date_delivered


class LabelHistory:
    """Load / save / query the local label history JSON file."""

    def __init__(self) -> None:
        from .paths import appdata_dir
        self._path: Path = appdata_dir() / "label_history.json"
        self._entries: list[LabelEntry] = self._load()

    # ── Persistence ────────────────────────────────────────────────────────

    def _load(self) -> list[LabelEntry]:
        try:
            if self._path.exists():
                raw = json.loads(self._path.read_text(encoding="utf-8"))
                return [LabelEntry(**r) for r in raw]
        except Exception as exc:
            log.warning("Could not load label history: %s", exc)
        return []

    def _save(self) -> None:
        try:
            data = [asdict(e) for e in self._entries]
            self._path.write_text(
                json.dumps(data, indent=2, default=str),
                encoding="utf-8",
            )
        except Exception as exc:
            log.warning("Could not save label history: %s", exc)

    # ── Mutation ───────────────────────────────────────────────────────────

    def add(self, entry: LabelEntry) -> None:
        self._entries.insert(0, entry)
        self._save()

    def mark_voided(self, label_id: str) -> None:
        for e in self._entries:
            if e.label_id == label_id:
                e.voided = True
                e.shipment_status = "Voided"
        self._save()

    def update_status(self, label_id: str, status: str,
                      date_delivered: str | None = None) -> None:
        for e in self._entries:
            if e.label_id == label_id:
                e.shipment_status = status
                if date_delivered:
                    e.date_delivered = date_delivered
        self._save()

    # ── Query ──────────────────────────────────────────────────────────────

    def all(self) -> list[LabelEntry]:
        return list(self._entries)

    def filter(
        self,
        search: str = "",
        status: str = "All",
        days: int | None = None,
        carrier: str = "",
    ) -> list[LabelEntry]:
        results = self._entries
        if carrier:
            results = [e for e in results if e.carrier == carrier]
        if days is not None:
            from datetime import timedelta, timezone
            cutoff = (datetime.now(timezone.utc) - timedelta(days=days)).isoformat()
            results = [e for e in results if e.date_printed >= cutoff]
        if status != "All":
            if status == "Voided":
                results = [e for e in results if e.voided]
            else:
                results = [e for e in results
                           if not e.voided and e.shipment_status == status]
        if search:
            q = search.lower()
            results = [
                e for e in results
                if q in e.recipient.lower()
                or q in e.notes.lower()
                or q in e.tracking_number.lower()
            ]
        return results