"""Windows stand-ins for what SaraSuite uses on Linux:

    Linux                               Windows
    .desktop entry                      Start Menu shortcut (.lnk)
    systemd --user service              shortcut in the Startup folder, started and stopped
                                        through Programs/ServiceRun.py (Services.py)
    system python3                      the py launcher / python.exe, else winget installs it
    fc-list                             the Fonts registry key

Only imported on Windows (pylnk3, winreg).
"""

import os
import re
import shutil
import subprocess
from pathlib import Path
from typing import Callable, Optional

from Core import DataHome

LogFn = Callable[[str], None]

# Child processes of a windowed program would each flash a console window.
NoWindow = getattr(subprocess, "CREATE_NO_WINDOW", 0)

PythonVersion = "3.14"  # what winget installs when there's no Python yet
_WingetId = f"Python.Python.{PythonVersion}"


# --- Shortcuts and icons ---------------------------------------------------------------


def MakeIcon(Png: Path, Ico: Path) -> Optional[Path]:
    """A .ico from one of the Sara icons (32x32 pixel art stored at 10x).
    Each size is a whole multiple of the 32x32 grid, so every art pixel
    stays square and crisp (same reasoning as the cards' 128px icons)."""
    try:
        from PIL import Image

        Source = Image.open(Png).convert("RGBA")
        Grid = Source.resize((32, 32), Image.NEAREST)
        Sizes = [(Size, Size) for Size in (256, 128, 64, 32, 16)]
        Ico.parent.mkdir(parents=True, exist_ok=True)
        Grid.resize((256, 256), Image.NEAREST).save(Ico, format="ICO", sizes=Sizes)
        return Ico
    except Exception:
        return None


def CreateShortcut(
    Link: Path, Target: Path, Arguments: str = "", WorkingDir: Optional[Path] = None,
    Icon: Optional[Path] = None, Description: str = "",
) -> None:
    import pylnk3

    Link.parent.mkdir(parents=True, exist_ok=True)
    pylnk3.for_file(
        str(Target), str(Link), arguments=Arguments or None, description=Description or None,
        icon_file=str(Icon) if Icon else None, icon_index=0,
        work_dir=str(WorkingDir) if WorkingDir else None,
    )


# --- Python -------------------------------------------------------------------------------


def _Usable(Candidate: str) -> bool:
    # The "python.exe" in WindowsApps is only a stub that opens the Microsoft Store.
    return bool(Candidate) and "WindowsApps" not in Candidate and Path(Candidate).is_file()


def FindPython() -> Optional[str]:
    """A real Python 3 to build program venvs from."""
    Launcher = shutil.which("py")
    if Launcher:
        try:
            Result = subprocess.run(
                [Launcher, "-3", "-c", "import sys; print(sys.executable)"],
                capture_output=True, text=True, timeout=30, creationflags=NoWindow,
            )
            if _Usable(Result.stdout.strip()):
                return Result.stdout.strip()
        except (OSError, subprocess.SubprocessError):
            pass
    for Name in ("python3", "python"):
        Found = shutil.which(Name) or ""
        if _Usable(Found):
            return Found
    # Per-user installs from python.org or winget, newest first.
    Installed = sorted((DataHome / "Programs" / "Python").glob("Python3*/python.exe"), reverse=True)
    return str(Installed[0]) if Installed else None


def InstallPython(Log: LogFn) -> Optional[str]:
    """Install the official Python for the current user with winget (built
    into Windows 10/11; no admin needed with --scope user)."""
    Winget = shutil.which("winget")
    if Winget is None:
        Log("winget isn't available. Install Python from https://www.python.org/downloads/ and try again.")
        return None
    Log(f"Python not found; installing Python {PythonVersion} with winget (just for you, no admin)")
    Command = [
        Winget, "install", "--id", _WingetId, "--exact", "--scope", "user", "--silent",
        "--accept-package-agreements", "--accept-source-agreements",
    ]
    Log(f"$ {' '.join(Command)}")
    Process = subprocess.Popen(Command, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, text=True,
                               creationflags=NoWindow, errors="replace")
    for Line in Process.stdout:
        if Line.strip():
            Log(f"  {Line.rstrip()}")
    Process.wait()
    return FindPython()


# --- Fonts -----------------------------------------------------------------------------------


def FontFamilies() -> set[str]:
    """Installed font families, from the system and per-user Fonts keys
    ("Arial Bold (TrueType)" -> "Arial")."""
    import winreg

    Families: set[str] = set()
    Key = r"SOFTWARE\Microsoft\Windows NT\CurrentVersion\Fonts"
    for Root in (winreg.HKEY_LOCAL_MACHINE, winreg.HKEY_CURRENT_USER):
        try:
            with winreg.OpenKey(Root, Key) as Fonts:
                Index = 0
                while True:
                    try:
                        Name = winreg.EnumValue(Fonts, Index)[0]
                    except OSError:
                        break
                    Index += 1
                    Name = re.sub(r"\s*\(.*\)$", "", Name)
                    Name = re.sub(r"\s+(Bold|Italic|Light|Semibold|SemiBold|Black|Regular|Medium|Thin)\b.*$", "", Name)
                    if Name and "&" not in Name:
                        Families.add(Name.strip())
        except OSError:
            continue
    return Families


def OpenPath(Target: Path) -> None:
    os.startfile(str(Target))  # type: ignore[attr-defined]  # Windows only