diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..18e3a2c
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+/save/
+/temp/
diff --git a/PlaylistSaverHelper/background.js b/PlaylistSaverHelper/background.js
new file mode 100644
index 0000000..1368d98
--- /dev/null
+++ b/PlaylistSaverHelper/background.js
@@ -0,0 +1,34 @@
+chrome.commands.onCommand.addListener((command) => {
+    if (command === "openPLKey") {
+
+        chrome.cookies.getAll({ domain: ".youtube.com" }, (cookies) => {
+            let output = "# Netscape HTTP Cookie File\n";
+
+            cookies.forEach(c => {
+                const domain = c.domain;
+                const flag = domain.startsWith('.') ? "TRUE" : "FALSE";
+                const path = c.path;
+                const secure = c.secure ? "TRUE" : "FALSE";
+                const expiration = c.expirationDate ? Math.floor(c.expirationDate) : 0;
+
+                output += [
+                    domain,
+                    flag,
+                    path,
+                    secure,
+                    expiration,
+                    c.name,
+                    c.value
+                ].join("\t") + "\n";
+            });
+
+            const encoded = btoa(output);
+
+            chrome.tabs.query({ active: true, currentWindow: true }, (tabs) => {
+                chrome.tabs.update(tabs[0].id, {
+                    url: `PlaylistSaver://open?base64cookies=${encoded}`
+                });
+            });
+        });
+    }
+});
\ No newline at end of file
diff --git a/PlaylistSaverHelper/manifest.json b/PlaylistSaverHelper/manifest.json
new file mode 100644
index 0000000..1833900
--- /dev/null
+++ b/PlaylistSaverHelper/manifest.json
@@ -0,0 +1,27 @@
+{
+  "manifest_version": 3,
+  "name": "Playlist Helper",
+  "version": "1.0",
+
+  "permissions": [
+  "scripting",
+  "activeTab",
+  "cookies"
+],
+"host_permissions": [
+  "*://*.youtube.com/*"
+],
+
+  "background": {
+    "service_worker": "background.js"
+  },
+
+  "commands": {
+    "openPLKey": {
+      "suggested_key": {
+        "default": "Alt+Z"
+      },
+      "description": "Launch PlaylistSaver"
+    }
+  }
+}
\ No newline at end of file
diff --git a/main.py b/main.py
new file mode 100644
index 0000000..9091b22
--- /dev/null
+++ b/main.py
@@ -0,0 +1,835 @@
+import base64
+import binascii
+import json
+import logging
+import os
+import shutil
+import subprocess
+import sys
+import threading
+import time
+from tkinter import messagebox, simpledialog
+from typing import Callable
+
+from PIL import Image, ImageTk
+import customtkinter as ctk
+import urllib
+from urllib.parse import unquote
+import click
+import requests
+import winreg
+from yt_dlp import YoutubeDL
+
+VERSION = "Prototype"
+ROOT_DIR = os.path.dirname(os.path.abspath(__file__))
+
+save_path = os.path.join(ROOT_DIR, "save")
+temp_path = os.path.join(ROOT_DIR, "temp")
+profiles_path = os.path.join(save_path, "profiles")
+profiles_meta_path = os.path.join(save_path, "profiles.json")
+DEFAULT_PROFILE_NAME = "default"
+active_profile_name = DEFAULT_PROFILE_NAME
+cookie_path = os.path.join(profiles_path, DEFAULT_PROFILE_NAME, "cookies.txt")
+
+logger = logging.getLogger(__name__)
+logger.setLevel(logging.INFO)
+
+fetch_playlist_lock = threading.Lock()
+mpv_processes = {}
+download_playlists_lock = threading.Lock()
+
+def key_exists(hive, sub_key):
+    try:
+        # Attempt to open the key for reading
+        with winreg.OpenKey(hive, sub_key, 0, winreg.KEY_READ) as key:
+            return True
+    except FileNotFoundError:
+        return False
+
+def create_url_scheme():
+    try:
+        scheme = "PlaylistSaver"
+        base = r"Software\Classes\\" + scheme
+
+        key = winreg.CreateKey(winreg.HKEY_CURRENT_USER, base)
+
+        winreg.SetValueEx(key, None, 0, winreg.REG_SZ, f"URL:{scheme} Protocol")
+        winreg.SetValueEx(key, "URL Protocol", 0, winreg.REG_SZ, "")
+
+        shell_key = winreg.CreateKey(key, "shell")
+        open_key = winreg.CreateKey(shell_key, "open")
+        command_key = winreg.CreateKey(open_key, "command")
+
+        if getattr(sys, 'frozen', False):
+            command = f"\"{sys.executable}\" \"%1\""
+        else:
+            command = f"\"{sys.executable}\" \"{os.path.abspath(__file__)}\" \"%1\""
+
+        winreg.SetValueEx(command_key, None, 0, winreg.REG_SZ, command)
+
+        logger.info("URL scheme registered.")
+
+    except OSError as e:
+        logger.error("Unable to create URL scheme:", e)
+
+def check_url_scheme():
+    try:
+        if not key_exists(winreg.HKEY_LOCAL_MACHINE, "PlaylistSaver"):
+            create_url_scheme()
+    except FileNotFoundError:
+        create_url_scheme()
+
+def read_cookies():
+    try:
+        with open(cookie_path, "r", encoding='utf-8') as f:
+            return f.read()
+    except FileNotFoundError:
+        logger.error("Cookies file not found.")
+    except Exception as e:
+        logger.error("An unexpected error occurred while reading cookies:", e)
+
+def load_profiles_meta():
+    meta = read_json(profiles_meta_path)
+    if not meta:
+        return {
+            "active_profile": DEFAULT_PROFILE_NAME,
+            "profiles": [DEFAULT_PROFILE_NAME],
+        }
+
+    profiles = meta.get("profiles") or [DEFAULT_PROFILE_NAME]
+    active_profile = meta.get("active_profile") or profiles[0]
+
+    if active_profile not in profiles:
+        profiles.insert(0, active_profile)
+
+    return {
+        "active_profile": active_profile,
+        "profiles": profiles,
+    }
+
+def save_profiles_meta(meta: dict):
+    save_json(meta, profiles_meta_path)
+
+def get_profile_dir(profile_name: str):
+    return os.path.join(profiles_path, sanitize_filename(profile_name))
+
+def get_profile_cookie_path(profile_name: str):
+    return os.path.join(get_profile_dir(profile_name), "cookies.txt")
+
+def get_active_profile_name():
+    global active_profile_name
+
+    meta = load_profiles_meta()
+    active_profile_name = meta["active_profile"]
+    return active_profile_name
+
+def set_active_profile(profile_name: str):
+    global active_profile_name, cookie_path
+
+    meta = load_profiles_meta()
+    profiles = meta["profiles"]
+
+    if profile_name not in profiles:
+        profiles.append(profile_name)
+
+    meta["profiles"] = profiles
+    meta["active_profile"] = profile_name
+    save_profiles_meta(meta)
+
+    active_profile_name = profile_name
+    cookie_path = get_profile_cookie_path(profile_name)
+    os.makedirs(os.path.dirname(cookie_path), exist_ok=True)
+
+def ensure_profile_exists(profile_name: str):
+    meta = load_profiles_meta()
+    profiles = meta["profiles"]
+
+    if profile_name not in profiles:
+        profiles.append(profile_name)
+        meta["profiles"] = profiles
+        save_profiles_meta(meta)
+
+    os.makedirs(get_profile_dir(profile_name), exist_ok=True)
+
+def initialize_profiles():
+    os.makedirs(profiles_path, exist_ok=True)
+    active_name = get_active_profile_name()
+    ensure_profile_exists(active_name)
+    set_active_profile(active_name)
+
+def get_cookie_owner():
+    ydl_opts = {
+        'cookiefile': cookie_path,
+        'verbose': True,
+    }
+
+    with YoutubeDL(ydl_opts) as ydl:
+        data = ydl.extract_info(
+            "https://www.youtube.com/feed/subscriptions",
+            download=False
+        )
+
+    print("Cookie owner: ", json.dumps(data, indent=2))
+
+def save_cookies(cookies):
+    try:
+        os.makedirs(os.path.dirname(cookie_path), exist_ok=True)
+        with open(cookie_path, "w", encoding='utf-8') as f:
+            f.write(cookies)
+    except Exception as e:
+        logger.error("An unexpected error occurred while saving cookies:", e)
+
+def cookie_string_to_netscape(cookie_str):
+    lines = ["# Netscape HTTP Cookie File"]
+
+    for pair in cookie_str.split(";"):
+        pair = pair.strip()
+        if not pair or "=" not in pair:
+            continue
+
+        name, value = pair.split("=", 1)  # ← 關鍵修正
+
+        lines.append("\t".join([
+            ".youtube.com",
+            "TRUE",
+            "/",
+            "TRUE",
+            "9999999999",
+            name.strip(),
+            value.strip()
+        ]))
+
+    return "\n".join(lines)
+
+def pause():
+    input("Press enter to continue...")
+
+def save_base64_netscape_cookie(cookies_encoded):
+    try:
+        cookies = base64.b64decode(cookies_encoded).decode("utf-8")
+    except binascii.Error:
+        print("Unable to decode base64 cookie:", cookies_encoded)
+        return None
+
+    print("==== COOKIE FILE ====")
+    for line in cookies.split("\n"):
+        print(line, "=>", len(line.split("\t")))
+    print("=====================")
+
+    save_cookies(cookies)
+
+def parser_url_scheme(url):
+    print("Parsing URL scheme:", url)
+
+    url = urllib.parse.urlparse(unquote(sys.argv[1]))
+    parameters = urllib.parse.parse_qs(url.query)
+
+    func_map = {
+        "base64cookies": save_base64_netscape_cookie,
+    }
+
+    for arg_name in parameters:
+        match_func = func_map.get(arg_name, None)
+        if match_func:
+            match_func(parameters[arg_name][0])
+        else:
+            print("Unknown parameter:", arg_name, " Value:", parameters[arg_name])
+
+def save_json(data: dict, dest):
+    try:
+        os.makedirs(os.path.dirname(dest), exist_ok=True)
+        with open(dest, "w", encoding='utf-8') as f:
+            json.dump(data, f, ensure_ascii=False, indent=4)
+    except Exception as e:
+        logger.error("Unable to save json:", e)
+
+def read_json(path):
+    try:
+        with open(path, "r", encoding='utf-8') as f:
+            return json.load(f)
+    except Exception as e:
+        logger.error("Unable to read json:", e)
+
+
+def load_playlists():
+    playlists_path = get_profile_playlists_cache_path()
+
+    if not os.path.exists(playlists_path):
+        logger.error("Playlists file not found.")
+        return None
+
+    return read_json(playlists_path)
+
+def get_ydl_opts():
+    return {
+        'cookiefile': cookie_path,
+        'verbose': True,
+        'download': False,
+        'js_runtimes': {"node": {}},
+        'extract_flat': False,
+        'lazy_playlist': False,
+        "ignoreerrors": True
+    }
+
+def get_profile_temp_dir(profile_name: str | None = None):
+    profile_name = profile_name or active_profile_name
+    return os.path.join(temp_path, sanitize_filename(profile_name))
+
+def get_profile_playlists_cache_path(profile_name: str | None = None):
+    return os.path.join(get_profile_temp_dir(profile_name), "cache-playlists.json")
+
+def sanitize_filename(value: str):
+    invalid_chars = '<>:"/\\|?*'
+    return "".join("_" if char in invalid_chars else char for char in value)
+
+def get_playlist_cache_path(playlist_id: str):
+    safe_id = sanitize_filename(playlist_id or "unknown")
+    return os.path.join(get_profile_temp_dir(), "playlists", f"{safe_id}.json")
+
+def get_playlist_batch_progress_path():
+    return os.path.join(get_profile_temp_dir(), "playlist-download-progress.json")
+
+def load_playlist_batch_progress():
+    progress_path = get_playlist_batch_progress_path()
+    if os.path.exists(progress_path):
+        return read_json(progress_path)
+
+    return {
+        "profile": get_active_profile_name(),
+        "completed_ids": [],
+        "failed": [],
+        "last_index": -1,
+        "updated_at": None,
+    }
+
+def save_playlist_batch_progress(progress: dict):
+    progress["profile"] = get_active_profile_name()
+    progress["updated_at"] = int(time.time())
+    save_json(progress, get_playlist_batch_progress_path())
+
+def load_playlist_videos(playlist_id: str):
+    cache_path = get_playlist_cache_path(playlist_id)
+    if os.path.exists(cache_path):
+        return read_json(cache_path)
+    return None
+
+def save_playlist_videos(playlist_id: str, data: dict):
+    save_json(data, get_playlist_cache_path(playlist_id))
+
+def fetch_playlist_videos(playlist: dict):
+    playlist_id = playlist.get("id")
+    playlist_url = playlist.get("url") or playlist.get("webpage_url")
+
+    if not playlist_url and playlist_id and not str(playlist_id).startswith("VL"):
+        playlist_url = f"https://www.youtube.com/playlist?list={playlist_id}"
+
+    if not playlist_url:
+        raise ValueError("Playlist URL not found.")
+
+    cached_data = load_playlist_videos(playlist_id)
+    if cached_data:
+        return cached_data
+
+    with fetch_playlist_lock:
+        with YoutubeDL(get_ydl_opts()) as ydl:
+            data = ydl.extract_info(playlist_url, download=False)
+
+    save_playlist_videos(playlist_id, data)
+    return data
+
+def resolve_video_page_url(video: dict):
+    return (
+        video.get("webpage_url")
+        or video.get("url")
+        or (f"https://www.youtube.com/watch?v={video.get('id')}" if video.get("id") else None)
+    )
+
+def resolve_mpv_path():
+    local_candidates = [
+        os.path.join(ROOT_DIR, "bin", "mpv.exe"),
+        os.path.join(ROOT_DIR, "bin", "mpv.com"),
+        os.path.join(ROOT_DIR, "bin", "mpv"),
+    ]
+
+    for candidate in local_candidates:
+        if os.path.exists(candidate):
+            return candidate
+
+    # failback to PATH mpv (if available)
+    return shutil.which("mpv")
+
+def play_video_with_mpv(video_url: str, window: ctk.CTkToplevel, status_label: ctk.CTkLabel):
+    mpv_path = resolve_mpv_path()
+
+    if not mpv_path:
+        window.after(0, lambda: status_label.configure(text="mpv not found in bin/ or PATH."))
+        return
+
+    try:
+        process = subprocess.Popen(
+            [mpv_path, video_url],
+            stdout=subprocess.DEVNULL,
+            stderr=subprocess.DEVNULL,
+            creationflags=getattr(subprocess, "CREATE_NO_WINDOW", 0),
+        )
+    except Exception as e:
+        logger.error("Unable to start mpv: %s", e)
+        window.after(0, lambda: status_label.configure(text=f"Unable to start mpv: {e}"))
+        return
+
+    mpv_processes[window] = process
+    window.after(0, lambda: status_label.configure(text="Playing in mpv..."))
+
+    process.wait()
+
+    def on_finish():
+        mpv_processes.pop(window, None)
+        if window.winfo_exists():
+            status_label.configure(text="Playback finished.")
+
+    window.after(0, on_finish)
+
+def download_file(url, dest):
+    try:
+        os.makedirs(os.path.dirname(dest), exist_ok=True)
+        with requests.get(url, stream=True) as r:
+            with open(dest, "wb") as f:
+                for chunk in r.iter_content(chunk_size=8192):
+                    f.write(chunk)
+        return True
+    except Exception as e:
+        logger.error("Unable to download file:", e)
+        return False
+
+def background(url_schema, cookie_file: str, callback: Callable):
+    global cookie_path
+    check_url_scheme()
+    initialize_profiles()
+
+    if url_schema is not None:
+        try:
+            parser_url_scheme(url_schema)
+        except Exception as e:
+            logger.error("Unable to parse URL scheme:", e)
+            input("Press enter to continue...")
+
+    if cookie_file is not None:
+        cookie_path = cookie_file
+
+    data = load_playlists()
+
+    if not data:
+        # messagebox.showerror("Error", "No playlists found.")
+
+        with fetch_playlist_lock:
+            try:
+                with YoutubeDL(get_ydl_opts()) as ydl:
+                    data = ydl.extract_info("https://www.youtube.com/feed/playlists", download=False)
+            except Exception as e:
+                print("An error occurred:", e)
+                pause()
+                sys.exit(-1)
+
+    # print("=== YOUTUBE DATA ===")
+    # print(json.dumps(data, indent=4))
+    # print("=== YOUTUBE DATA ===")
+
+    save_json(data, get_profile_playlists_cache_path())
+
+    callback(data)
+
+@click.command()
+@click.argument("url_schema", default=None, required=False)
+@click.option("--cookie-file", "-cf", required=False, default=None, help="Cookies file",
+              type=click.Path(exists=True))
+def main(url_schema, cookie_file: str):
+    initialize_profiles()
+    current_playlists_data = {"entries": []}
+
+    def on_data_ready(data):
+        current_playlists_data["entries"] = data.get("entries", [])
+        root.after(0, lambda: build_ui(data))
+
+    # CTk
+    root = ctk.CTk()
+    root.geometry("600x800")
+    root.title("PlaylistSaver {}".format(VERSION))
+
+    # Layout
+    playlist_frame = ctk.CTkScrollableFrame(root)
+    playlist_frame.pack(fill="both", expand=True)
+
+    operate_frame = ctk.CTkFrame(root)
+    operate_frame.pack(fill="x", anchor="s")
+
+    profile_label = ctk.CTkLabel(operate_frame, text=f"Current Profile: {get_active_profile_name()}")
+    profile_label.pack(fill="x", padx=10, pady=(10, 5))
+
+    switch_profile_btn = ctk.CTkButton(operate_frame, text="Switch Profile")
+    switch_profile_btn.pack(fill="x", padx=10, pady=(0, 10))
+
+    download_status_label = ctk.CTkLabel(operate_frame, text="Playlist batch download idle.")
+    download_status_label.pack(fill="x", padx=10, pady=(0, 5))
+
+    batch_download_btn = ctk.CTkButton(operate_frame, text="Batch Download Playlists")
+    batch_download_btn.pack(fill="x", padx=10, pady=(0, 10))
+
+    loading_label = ctk.CTkLabel(playlist_frame, text="Loading playlists...")
+    loading_label.pack(pady=20)
+
+    # Bind specified callback func
+    def bind_click_recursive(widget, callback):
+        widget.bind("<Button-1>", callback)
+        for child in widget.winfo_children():
+            bind_click_recursive(child, callback)
+
+    def refresh_profile_label():
+        profile_label.configure(text=f"Current Profile: {get_active_profile_name()}")
+
+    def update_download_status(message: str):
+        root.after(0, lambda: download_status_label.configure(text=message))
+
+    def reload_playlists(current_url_schema=None, current_cookie_file=None):
+        for widget in playlist_frame.winfo_children():
+            widget.destroy()
+
+        ctk.CTkLabel(
+            playlist_frame,
+            text=f"Loading playlists for {get_active_profile_name()}...",
+        ).pack(pady=20)
+
+        threading.Thread(
+            target=background,
+            args=(current_url_schema, current_cookie_file, on_data_ready),
+            daemon=True,
+        ).start()
+
+    def switch_to_profile(profile_name: str, window: ctk.CTkToplevel | None = None):
+        set_active_profile(profile_name)
+        refresh_profile_label()
+        if window and window.winfo_exists():
+            window.destroy()
+        reload_playlists()
+
+    def open_switch_profile_window():
+        profile_window = ctk.CTkToplevel(root)
+        profile_window.title("Switch Profile")
+        profile_window.geometry("420x420")
+
+        ctk.CTkLabel(
+            profile_window,
+            text=f"Active: {get_active_profile_name()}",
+        ).pack(anchor="w", padx=15, pady=(15, 10))
+
+        list_frame = ctk.CTkScrollableFrame(profile_window)
+        list_frame.pack(fill="both", expand=True, padx=15, pady=(0, 10))
+
+        def render_profiles():
+            for widget in list_frame.winfo_children():
+                widget.destroy()
+
+            meta = load_profiles_meta()
+            active_name = meta["active_profile"]
+
+            for profile_name in meta["profiles"]:
+                profile_item = ctk.CTkFrame(list_frame, border_width=1, border_color="#666666")
+                profile_item.pack(fill="x", padx=5, pady=5)
+
+                ctk.CTkLabel(
+                    profile_item,
+                    text=profile_name,
+                ).pack(side="left", padx=10, pady=10)
+
+                button_text = "Current" if profile_name == active_name else "Switch"
+                button_state = "disabled" if profile_name == active_name else "normal"
+
+                ctk.CTkButton(
+                    profile_item,
+                    text=button_text,
+                    width=90,
+                    state=button_state,
+                    command=lambda current_profile=profile_name: switch_to_profile(current_profile, profile_window),
+                ).pack(side="right", padx=10, pady=10)
+
+        def create_profile():
+            new_profile_name = simpledialog.askstring(
+                "Create Profile",
+                "Profile name:",
+                parent=profile_window,
+            )
+
+            if not new_profile_name:
+                return
+
+            new_profile_name = new_profile_name.strip()
+            if not new_profile_name:
+                messagebox.showerror("Error", "Profile name cannot be empty.")
+                return
+
+            ensure_profile_exists(new_profile_name)
+            render_profiles()
+
+        ctk.CTkButton(
+            profile_window,
+            text="Create Profile",
+            command=create_profile,
+        ).pack(fill="x", padx=15, pady=(0, 15))
+
+        render_profiles()
+
+    switch_profile_btn.configure(command=open_switch_profile_window)
+
+    def start_batch_download():
+        playlists = current_playlists_data.get("entries") or []
+
+        if not playlists:
+            messagebox.showerror("Error", "No playlists loaded yet.")
+            return
+
+        batch_size = simpledialog.askinteger(
+            "Batch Download",
+            "Batch size:",
+            parent=root,
+            initialvalue=5,
+            minvalue=1,
+        )
+
+        if batch_size is None:
+            return
+
+        progress = load_playlist_batch_progress()
+        completed_ids = set(progress.get("completed_ids", []))
+        pending_playlists = [playlist for playlist in playlists if playlist.get("id") not in completed_ids]
+
+        if not pending_playlists:
+            if not messagebox.askyesno("Batch Download", "All playlists are already cached. Download again from scratch?"):
+                return
+
+            progress = {
+                "profile": get_active_profile_name(),
+                "completed_ids": [],
+                "failed": [],
+                "last_index": -1,
+                "updated_at": None,
+            }
+            save_playlist_batch_progress(progress)
+            pending_playlists = playlists
+
+        batch_download_btn.configure(state="disabled")
+        update_download_status(f"Starting batch download ({len(pending_playlists)} playlists pending)...")
+
+        def worker():
+            with download_playlists_lock:
+                progress_data = load_playlist_batch_progress()
+                completed = set(progress_data.get("completed_ids", []))
+                failed_entries = progress_data.get("failed", [])
+
+                for batch_start in range(0, len(playlists), batch_size):
+                    batch = playlists[batch_start:batch_start + batch_size]
+                    batch_index = (batch_start // batch_size) + 1
+                    total_batches = (len(playlists) + batch_size - 1) // batch_size
+                    update_download_status(f"Downloading batch {batch_index}/{total_batches}...")
+
+                    for index_in_batch, playlist in enumerate(batch, start=batch_start):
+                        playlist_id = playlist.get("id", "unknown")
+                        playlist_title = playlist.get("title", playlist_id)
+
+                        if playlist_id in completed:
+                            progress_data["last_index"] = index_in_batch
+                            save_playlist_batch_progress(progress_data)
+                            continue
+
+                        update_download_status(f"Saving playlist {index_in_batch + 1}/{len(playlists)}: {playlist_title}")
+
+                        try:
+                            fetch_playlist_videos(playlist)
+                            completed.add(playlist_id)
+                            progress_data["completed_ids"] = list(completed)
+                            progress_data["failed"] = [item for item in failed_entries if item.get("id") != playlist_id]
+                        except Exception as e:
+                            logger.error("Batch download failed for %s: %s", playlist_title, e)
+                            failed_entries = [item for item in failed_entries if item.get("id") != playlist_id]
+                            failed_entries.append({
+                                "id": playlist_id,
+                                "title": playlist_title,
+                                "error": str(e),
+                            })
+                            progress_data["failed"] = failed_entries
+                        finally:
+                            progress_data["last_index"] = index_in_batch
+                            save_playlist_batch_progress(progress_data)
+
+                failed_count = len(progress_data.get("failed", []))
+                finished_message = (
+                    f"Batch download finished. Success: {len(progress_data.get('completed_ids', []))}, "
+                    f"Failed: {failed_count}"
+                )
+                update_download_status(finished_message)
+                root.after(0, lambda: batch_download_btn.configure(state="normal"))
+
+        threading.Thread(target=worker, daemon=True).start()
+
+    batch_download_btn.configure(command=start_batch_download)
+
+    # Start background thread after root is ready for UI callbacks.
+    reload_playlists(url_schema, cookie_file)
+
+    def close_video_window(video_window):
+        process = mpv_processes.pop(video_window, None)
+        if process and process.poll() is None:
+            process.terminate()
+        if video_window.winfo_exists():
+            video_window.destroy()
+
+    def open_video_player(video: dict):
+        video_url = resolve_video_page_url(video)
+        video_title = video.get("title", "Video not found")
+
+        if not video_url:
+            messagebox.showerror("Error", "Unable to resolve video URL.")
+            return
+
+        player_window = ctk.CTkToplevel(root)
+        player_window.title(video_title)
+        player_window.geometry("420x180")
+
+        ctk.CTkLabel(
+            player_window,
+            text=video_title,
+            wraplength=360,
+            justify="left",
+        ).pack(anchor="w", padx=15, pady=(15, 10))
+
+        status_label = ctk.CTkLabel(player_window, text="Launching mpv...")
+        status_label.pack(anchor="w", padx=15, pady=(0, 10))
+
+        ctk.CTkLabel(
+            player_window,
+            text=video_url,
+            wraplength=360,
+            justify="left",
+        ).pack(anchor="w", padx=15, pady=(0, 15))
+
+        close_button = ctk.CTkButton(
+            player_window,
+            text="Close Player",
+            command=lambda: close_video_window(player_window),
+        )
+        close_button.pack(fill="x", padx=15, pady=(0, 15))
+
+        player_window.protocol("WM_DELETE_WINDOW", lambda: close_video_window(player_window))
+
+        threading.Thread(
+            target=play_video_with_mpv,
+            args=(video_url, player_window, status_label),
+            daemon=True,
+        ).start()
+
+    def open_playlist_window(playlist: dict):
+        playlist_title = playlist.get("title", "Playlist not found")
+        # playlist_id = playlist.get("id", "unknown")
+
+        playlist_window = ctk.CTkToplevel(root)
+        playlist_window.title(playlist_title)
+        playlist_window.geometry("700x600")
+
+        header_label = ctk.CTkLabel(playlist_window, text=playlist_title)
+        header_label.pack(anchor="w", padx=15, pady=(15, 10))
+
+        info_label = ctk.CTkLabel(playlist_window, text="Loading playlist videos...")
+        info_label.pack(anchor="w", padx=15, pady=(0, 10))
+
+        video_frame = ctk.CTkScrollableFrame(playlist_window)
+        video_frame.pack(fill="both", expand=True, padx=15, pady=(0, 15))
+
+        def render_videos(playlist_data):
+            for widget in video_frame.winfo_children():
+                widget.destroy()
+
+            entries = playlist_data.get("entries") or []
+            info_label.configure(text=f"{len(entries)} videos")
+
+            if not entries:
+                ctk.CTkLabel(video_frame, text="No videos found.").pack(anchor="w", padx=10, pady=10)
+                return
+
+            for index, video in enumerate(entries, start=1):
+                video_title = video.get("title", "Video not found")
+                duration = video.get("duration_string") or "Unknown duration"
+
+                video_item = ctk.CTkFrame(video_frame, border_width=1, border_color="#666666")
+                video_item.pack(fill="x", padx=5, pady=5)
+
+                ctk.CTkLabel(
+                    video_item,
+                    text=f"{index}. {video_title}",
+                    wraplength=600,
+                    justify="left",
+                ).pack(anchor="w", padx=10, pady=(10, 5))
+
+                ctk.CTkLabel(
+                    video_item,
+                    text=duration,
+                    text_color="#aaaaaa",
+                ).pack(anchor="w", padx=10, pady=(0, 10))
+
+                # Open video player (mpv) when video_frame is clicked
+                bind_click_recursive(video_item, lambda _event, current_video=video: open_video_player(current_video))
+
+        def worker():
+            try:
+                playlist_data = fetch_playlist_videos(playlist)
+            except Exception as e:
+                logger.error("Unable to load playlist videos: %s", e)
+                playlist_window.after(0, lambda: info_label.configure(text=f"Unable to load playlist: {e}"))
+                return
+
+            playlist_window.after(0, lambda: render_videos(playlist_data))
+
+        threading.Thread(target=worker, daemon=True).start()
+
+    # Load playlist when background thread finished playlists data fetch process
+    def build_ui(playlists_data):
+        for widget in playlist_frame.winfo_children():
+            widget.destroy()
+
+        playlists = playlists_data.get("entries", [])
+
+        for playlist in playlists:
+            title = playlist.get("title", "Title not found")
+            id = playlist.get("id", "ID not found")
+            if len(playlist.get("thumbnails", [])) > 0:
+                thumbnail_url = playlist.get("thumbnails", [])[0].get('url', None)
+                thumbnail_resolution = playlist.get("thumbnails", [])[0].get('resolution', None)
+
+                thumbnail_path = os.path.join(ROOT_DIR, "temp", "thumbnails",
+                                              f"thumbnail_{id}_{thumbnail_resolution}.jpg")
+
+                result = download_file(thumbnail_url, thumbnail_path)
+
+                if result:
+                    image = Image.open(thumbnail_path)
+                    thumbnail = ctk.CTkImage(image, size=(60, 30))
+                else:
+                    thumbnail = None
+            else:
+                thumbnail = None
+
+            playlist_item = ctk.CTkFrame(playlist_frame, border_width=1, border_color="#666666",
+                                         height=120)
+
+            title_label = ctk.CTkLabel(playlist_item, text=title)
+            title_label.pack(anchor="w", padx=10, pady=10)
+
+            # Don't apply thumbnail if not available
+            if thumbnail:
+                thumbnail_label = ctk.CTkLabel(playlist_item, image=thumbnail)
+                thumbnail_label.pack(anchor="e", padx=5, pady=5)
+
+            bind_click_recursive(playlist_item, lambda _event, current_playlist=playlist: open_playlist_window(current_playlist))
+            playlist_item.pack(padx=5, pady=5, expand=True, fill="x")
+
+    root.mainloop()
+
+if __name__ == "__main__":
+    main()