from __future__ import annotations

import shutil
from pathlib import Path

from app.pipeline.file_manager import (
    check_dir_write_access,
    create_run_context,
    move_file_to_error,
    next_run_number,
    scan_input_files,
)


class FakeSamba:
    def __init__(self, root: Path) -> None:
        self.root = root

    def __enter__(self):
        return self

    def __exit__(self, exc_type, exc, tb):  # noqa: ANN001
        return False

    def _to_local(self, remote_path: str) -> Path:
        cleaned = remote_path.replace("/", "\\").strip("\\")
        return self.root / Path(cleaned)

    def path_exists(self, path: str) -> bool:
        return self._to_local(path).exists()

    def listdir(self, path: str) -> list[str]:
        target = self._to_local(path)
        if not target.exists():
            return []
        return [item.name for item in target.iterdir()]

    def is_file(self, path: str) -> bool:
        return self._to_local(path).is_file()

    def mkdir(self, path: str, parent: bool = False) -> None:
        target = self._to_local(path)
        if parent:
            target.mkdir(parents=True, exist_ok=True)
        else:
            target.mkdir(exist_ok=True)

    def copy(self, path_from: str, path_to: str, replace: bool = False) -> None:
        source = self._to_local(path_from)
        target = self._to_local(path_to)
        target.parent.mkdir(parents=True, exist_ok=True)
        if target.exists() and not replace:
            raise FileExistsError(path_to)
        shutil.copy2(source, target)

    def delete(self, path: str) -> None:
        target = self._to_local(path)
        if target.exists():
            target.unlink()

    def rename(self, path_from: str, path_to: str, replace: bool = False) -> None:
        source = self._to_local(path_from)
        target = self._to_local(path_to)
        target.parent.mkdir(parents=True, exist_ok=True)
        if target.exists() and not replace:
            raise FileExistsError(path_to)
        source.rename(target)

    def open(self, path: str, mode: str = "rb"):
        target = self._to_local(path)
        target.parent.mkdir(parents=True, exist_ok=True)
        return target.open(mode)


def test_scan_input_files_splits_valid_and_invalid(tmp_path: Path) -> None:
    samba = FakeSamba(tmp_path)
    in_dir = "Exchange\\SMBDEMO\\test"
    local_dir = tmp_path / "Exchange" / "SMBDEMO" / "test"
    local_dir.mkdir(parents=True)
    (local_dir / "SKO115FZ_01_123456789_20260616_X00001.xml").write_text(
        "ok", encoding="utf-8"
    )
    (local_dir / "wrong_name.xml").write_text("bad", encoding="utf-8")

    result = scan_input_files(in_dir, samba)
    assert len(result.valid_files) == 1
    assert len(result.invalid_files) == 1


def test_next_run_number_reads_existing_dirs(tmp_path: Path) -> None:
    samba = FakeSamba(tmp_path)
    out_day = (
        tmp_path / "Exchange" / "SMBDEMO" / "Out" / "2026" / "06_2026" / "20260616"
    )
    (out_day / "1").mkdir(parents=True)
    (out_day / "2").mkdir(parents=True)

    number = next_run_number("Exchange\\SMBDEMO\\Out\\2026\\06_2026\\20260616", samba)
    assert number == 3


def test_create_run_context_creates_paths(tmp_path: Path) -> None:
    samba = FakeSamba(tmp_path)
    context = create_run_context("Exchange\\SMBDEMO\\test", samba)

    assert context.run_number == 1
    assert (tmp_path / Path(context.run_dir)).exists()
    assert (tmp_path / Path(context.error_dir)).exists()
    assert (tmp_path / Path(context.processed_dir)).exists()


def test_move_file_to_error_adds_suffix_on_collision(tmp_path: Path) -> None:
    samba = FakeSamba(tmp_path)
    error_dir = tmp_path / "Exchange" / "SMBDEMO" / "Err"
    error_dir.mkdir(parents=True)
    (error_dir / "file.xml").write_text("existing", encoding="utf-8")
    source = tmp_path / "Exchange" / "SMBDEMO" / "test" / "file.xml"
    source.parent.mkdir(parents=True)
    source.write_text("new", encoding="utf-8")

    target = move_file_to_error(
        file_path="Exchange\\SMBDEMO\\test\\file.xml",
        file_name="file.xml",
        error_dir="Exchange\\SMBDEMO\\Err",
        samba_conn=samba,
    )
    assert target.endswith("file_1.xml")
    assert (error_dir / "file_1.xml").exists()


def test_check_dir_write_access_success(tmp_path: Path) -> None:
    samba = FakeSamba(tmp_path)
    target_dir = tmp_path / "Exchange" / "SMBDEMO" / "Out"
    target_dir.mkdir(parents=True)

    ok, error = check_dir_write_access(
        target_dir="Exchange\\SMBDEMO\\Out",
        samba_conn=samba,
        source_name="Out",
    )

    assert ok is True
    assert error is None


def test_check_dir_write_access_fails_without_open_or_upload(tmp_path: Path) -> None:
    class NoWriteSamba(FakeSamba):
        open = None  # type: ignore[assignment]

    samba = NoWriteSamba(tmp_path)
    target_dir = tmp_path / "Exchange" / "SMBDEMO" / "Out"
    target_dir.mkdir(parents=True)

    ok, error = check_dir_write_access(
        target_dir="Exchange\\SMBDEMO\\Out",
        samba_conn=samba,
        source_name="Out",
    )

    assert ok is False
    assert error is not None