import csv
import os
import shutil
from pathlib import Path


def default_desktop() -> Path:
    user_profile = Path(os.environ.get("USERPROFILE", str(Path.home())))
    return user_profile / "Desktop"


def read_csv(csv_path: Path) -> list[dict[str, str]]:
    if not csv_path.is_file():
        raise ValueError(f"Die CSV-Datei existiert nicht: {csv_path}")

    with csv_path.open("r", newline="", encoding="latin-1") as csv_file:
        return list(csv.DictReader(csv_file, delimiter=";"))


def move_files(
    files_csv: Path,
    clients_csv: Path,
    desktop_directory: Path | None = None,
) -> tuple[int, int, int]:
    desktop_directory = desktop_directory or default_desktop()
    client_rows = read_csv(clients_csv)
    client_names = {
        row.get("ParticipantName", "").strip(): row.get("Kunde", "").strip()
        for row in client_rows
        if row.get("ParticipantName", "").strip() and row.get("Kunde", "").strip()
    }

    moved_count = 0
    skipped_count = 0
    missing_client_count = 0
    for row in read_csv(files_csv):
        participant_name = row.get("ParticipantName", "").strip()
        source = Path(row.get("FilePath", "").strip())
        customer = client_names.get(participant_name)
        if not customer:
            missing_client_count += 1
            continue
        if not source.is_file():
            skipped_count += 1
            continue

        target_directory = desktop_directory / "PC-Visit" / customer
        target_directory.mkdir(parents=True, exist_ok=True)
        target = target_directory / source.name
        if source.resolve() == target.resolve() or target.exists():
            skipped_count += 1
            continue
        shutil.move(str(source), str(target))
        moved_count += 1

    return moved_count, skipped_count, missing_client_count