"""Konfigurations-Loader (TOML)."""
from __future__ import annotations

import tomllib
from dataclasses import dataclass, field
from pathlib import Path
from typing import Any


@dataclass
class Paths:
    incoming: Path
    outgoing: Path
    working: Path
    error: Path


@dataclass
class OcrConfig:
    languages: str = "deu+eng"
    jobs: int = 4
    skip_text: bool = True
    oversample: int = 300
    pdfa_level: str = "2"
    deskew: bool = True
    clean: bool = False
    max_workers: int = 2
    timeout: int = 1800


@dataclass
class VeraPdfConfig:
    enabled: bool = False
    binary: str = "/opt/verapdf/verapdf"
    flavour: str = "1b"


@dataclass
class FolderUpload:
    enabled: bool = True
    target: str = ""


@dataclass
class NextcloudUpload:
    enabled: bool = False
    url: str = ""
    username: str = ""
    password: str = ""
    remote_path: str = ""
    verify_ssl: bool = True


@dataclass
class SftpUpload:
    enabled: bool = False
    host: str = ""
    port: int = 22
    username: str = ""
    key_file: str = ""
    password: str = ""
    remote_path: str = ""


@dataclass
class EmailNotify:
    enabled: bool = False
    smtp_host: str = ""
    smtp_port: int = 587
    smtp_user: str = ""
    smtp_password: str = ""
    use_starttls: bool = True
    from_addr: str = ""
    to_addrs: list[str] = field(default_factory=list)
    on: str = "errors"  # always | errors | never


@dataclass
class Config:
    paths: Paths
    ocr: OcrConfig
    verapdf: VeraPdfConfig
    folder: FolderUpload
    nextcloud: NextcloudUpload
    sftp: SftpUpload
    email: EmailNotify
    log_level: str = "INFO"


def _section(data: dict[str, Any], *keys: str) -> dict[str, Any]:
    cur: Any = data
    for k in keys:
        cur = cur.get(k, {}) if isinstance(cur, dict) else {}
    return cur if isinstance(cur, dict) else {}


def load_config(path: str | Path) -> Config:
    path = Path(path)
    with path.open("rb") as f:
        data = tomllib.load(f)

    p = _section(data, "paths")
    paths = Paths(
        incoming=Path(p["incoming"]),
        outgoing=Path(p["outgoing"]),
        working=Path(p["working"]),
        error=Path(p["error"]),
    )

    ocr = OcrConfig(**{k: v for k, v in _section(data, "ocr").items()
                       if k in OcrConfig.__annotations__})
    verapdf = VeraPdfConfig(**{k: v for k, v in _section(data, "verapdf").items()
                               if k in VeraPdfConfig.__annotations__})
    folder = FolderUpload(**{k: v for k, v in _section(data, "upload", "folder").items()
                             if k in FolderUpload.__annotations__})
    nextcloud = NextcloudUpload(**{k: v for k, v in _section(data, "upload", "nextcloud").items()
                                   if k in NextcloudUpload.__annotations__})
    sftp = SftpUpload(**{k: v for k, v in _section(data, "upload", "sftp").items()
                         if k in SftpUpload.__annotations__})
    email = EmailNotify(**{k: v for k, v in _section(data, "notify", "email").items()
                           if k in EmailNotify.__annotations__})

    log_level = _section(data, "logging").get("level", "INFO")

    return Config(
        paths=paths, ocr=ocr, verapdf=verapdf,
        folder=folder, nextcloud=nextcloud, sftp=sftp, email=email,
        log_level=log_level,
    )