"""Small typed records shared by the storage, scanner and UI layers."""

from __future__ import annotations

from dataclasses import dataclass, field
from datetime import datetime, timezone
from pathlib import Path


def now_iso() -> str:
    return datetime.now(timezone.utc).isoformat(timespec="seconds").replace("+00:00", "Z")


@dataclass
class Detection:
    path: str
    signature: str
    action: str = "detected"
    quarantine_id: str | None = None
    size: int = 0
    detected_at: str = ""
    id: int | None = None

    def __post_init__(self) -> None:
        if not self.detected_at:
            self.detected_at = now_iso()


@dataclass
class ScanRecord:
    id: int | None
    started_at: str
    finished_at: str | None
    scope: str
    status: str
    paths: list[str]
    scanned_files: int = 0
    infected_files: int = 0
    errors: int = 0
    engine_version: str = ""
    db_version: str = ""
    duration_seconds: float = 0.0
    cancelled: bool = False
    detections: list[Detection] = field(default_factory=list)

    @property
    def scope_label(self) -> str:
        return "Full disk" if self.scope == "full" else "User homes"

    @property
    def threat_count(self) -> int:
        return max(self.infected_files, len(self.detections))


@dataclass
class QuarantineItem:
    id: str
    original_path: str
    quarantine_path: str
    signature: str
    sha256: str
    size: int
    created_at: str
    status: str = "quarantined"
    scan_id: int | None = None


@dataclass
class RealtimeEvent:
    created_at: str
    path: str
    signature: str
    action: str
    detail: str = ""
    id: int | None = None


@dataclass
class ClamAVInfo:
    available: bool
    path: Path | None = None
    engine_version: str = ""
    db_version: str = ""
    db_path: Path | None = None
    db_date: str = ""
    db_age_days: float | None = None
    error: str = ""

    @property
    def db_fresh(self) -> bool:
        return self.db_age_days is not None and self.db_age_days <= 7

    @property
    def summary(self) -> str:
        if not self.available:
            return self.error or "ClamAV not found"
        bits = [self.engine_version or "ClamAV"]
        if self.db_version:
            bits.append(f"signatures {self.db_version}")
        if self.db_age_days is not None:
            bits.append(f"{self.db_age_days:.0f}d old")
        return " · ".join(bits)


@dataclass
class UpdateAsset:
    id: str
    name: str
    size: int
    content_type: str
    download_url: str


@dataclass
class UpdateRelease:
    id: str
    tag: str
    name: str
    notes: str
    prerelease: bool
    published_at: str
    html_url: str
    assets: list[UpdateAsset] = field(default_factory=list)


@dataclass
class UpdateFeed:
    channel: str
    latest: UpdateRelease | None
    releases: list[UpdateRelease]
    checked_at: str

    @classmethod
    def from_api(cls, payload: dict) -> "UpdateFeed":
        def release_from(item: dict) -> UpdateRelease:
            assets = [
                UpdateAsset(
                    id=str(asset.get("id") or ""),
                    name=str(asset.get("name") or "download"),
                    size=int(asset.get("size") or 0),
                    content_type=str(asset.get("content_type") or ""),
                    download_url=str(asset.get("download_url") or ""),
                )
                for asset in (item.get("assets") or [])
                if isinstance(asset, dict)
            ]
            return UpdateRelease(
                id=str(item.get("id") or ""),
                tag=str(item.get("tag") or ""),
                name=str(item.get("name") or item.get("tag") or ""),
                notes=str(item.get("notes") or ""),
                prerelease=bool(item.get("prerelease")),
                published_at=str(item.get("published_at") or item.get("created_at") or ""),
                html_url=str(item.get("html_url") or ""),
                assets=assets,
            )

        releases = [release_from(item) for item in (payload.get("releases") or [])
                    if isinstance(item, dict)]
        latest_raw = payload.get("latest")
        latest = release_from(latest_raw) if isinstance(latest_raw, dict) else (
            releases[0] if releases else None)
        return cls(
            channel=str(payload.get("channel") or "release"),
            latest=latest,
            releases=releases,
            checked_at=str(payload.get("checked_at") or now_iso()),
        )


def display_name(path: str) -> str:
    """Basename for a Windows or POSIX path, independent of host OS."""
    text = str(path or "")
    name = Path(text.replace("\\", "/")).name
    return name or text


def human_scope(scope: str) -> str:
    return "Full disk" if scope == "full" else "User homes"


def human_action(action: str) -> str:
    return {
        "detected": "Detected",
        "quarantined": "Quarantined",
        "deleted": "Deleted",
        "failed": "Action failed",
        "ignored": "Ignored",
        "allowed": "Allowed",
        "blocked": "Blocked",
    }.get(action, action.replace("_", " ").title())