"""Use the Windows folder picker without shipping Tcl/Tk."""
from __future__ import annotations
import base64
import json
import os
import subprocess


def pick_folder(current):
    from host.bundle import installation_root
    installed = installation_root()
    if installed:
        encoded = base64.b64encode(json.dumps(current or "").encode("utf-8")).decode("ascii")
        result = subprocess.run([str(installed / "YouTubeDL-Manager.exe"), "--pick-folder", "--initial-folder", encoded],
                                capture_output=True, text=True, encoding="utf-8", errors="replace", timeout=600,
                                creationflags=subprocess.CREATE_NO_WINDOW)
        if result.returncode:
            raise ValueError("Не удалось открыть окно выбора папки Windows.")
        return json.loads(result.stdout.strip().lstrip("\ufeff"))
    if os.name != "nt":
        import tkinter
        from tkinter import filedialog
        root = tkinter.Tk()
        try:
            root.withdraw(); root.attributes("-topmost", True)
            return filedialog.askdirectory(initialdir=current or "", mustexist=True) or None
        finally:
            root.destroy()
    # Only base64 data is substituted; paths are never interpolated into shell code.
    encoded = base64.b64encode(json.dumps(current or "").encode("utf-8")).decode("ascii")
    script = """
$ErrorActionPreference='Stop'
[Console]::OutputEncoding=[Text.UTF8Encoding]::new()
Add-Type -AssemblyName System.Windows.Forms
$taskDialog=[Windows.Forms.FolderBrowserDialog]::new()
$taskOwner=[Windows.Forms.Form]::new()
try {
  $taskOwner.TopMost=$true; $taskOwner.ShowInTaskbar=$false; $taskOwner.Opacity=0
  $taskDialog.Description='YouTubeDL — папка сохранения'
  $taskDialog.ShowNewFolderButton=$true
  $taskDialog.SelectedPath=([Text.Encoding]::UTF8.GetString([Convert]::FromBase64String('ENCODED')) | ConvertFrom-Json)
  $taskOwner.Show()
  $taskChosen=$null
  if($taskDialog.ShowDialog($taskOwner) -eq [Windows.Forms.DialogResult]::OK){$taskChosen=$taskDialog.SelectedPath}
  ConvertTo-Json -InputObject $taskChosen -Compress
} finally {$taskDialog.Dispose();$taskOwner.Dispose()}
""".replace("ENCODED", encoded)
    argument = base64.b64encode(script.encode("utf-16le")).decode("ascii")
    powershell = os.path.join(os.environ.get("SystemRoot", r"C:\Windows"), "System32", "WindowsPowerShell", "v1.0", "powershell.exe")
    result = subprocess.run([powershell, "-NoProfile", "-ExecutionPolicy", "Bypass", "-STA", "-EncodedCommand", argument],
                            capture_output=True, text=True, encoding="utf-8", errors="replace", timeout=600,
                            creationflags=subprocess.CREATE_NO_WINDOW,
                            env={**os.environ, "PSModulePath": os.path.join(os.path.dirname(powershell), "Modules")})
    if result.returncode:
        raise ValueError("Не удалось открыть окно выбора папки Windows.")
    return json.loads(result.stdout.strip().lstrip("\ufeff"))