# Monkey patch MUST be first - before any other imports!
import eventlet
eventlet.monkey_patch()

import os
import json
import subprocess
import threading
import queue
import time
from flask import Flask, send_from_directory, jsonify, request, session, Response, stream_with_context
from flask_socketio import SocketIO, emit
from dotenv import load_dotenv
# Load environment variables from .env file
load_dotenv()
import downloader


def _load_config():
    """Loads optional config.json from the project root.

    If missing or invalid, returns an empty dict.
    """
    try:
        with open('config.json', 'r', encoding='utf-8') as f:
            data = json.load(f)
        return data if isinstance(data, dict) else {}
    except FileNotFoundError:
        return {}
    except Exception:
        return {}


CONFIG = _load_config()
DJ_PANEL_PASSWORD = (CONFIG.get('dj_panel_password') or '').strip()
DJ_AUTH_ENABLED = bool(DJ_PANEL_PASSWORD)

# Relay State
broadcast_state = {
    'active': False,
    'remote_relay': False,
    'server_mix': False,
}
listener_sids = set()
dj_sids = set()

# DJ identity mapping (for auto-reclaim)
dj_identity_by_sid: dict[str, str] = {}
last_controller_identity: str | None = None
last_controller_released_at: float = 0.0

# === Multi-DJ controller lock (one active controller at a time) ===
active_controller_sid = None


def _emit_controller_status(to_sid: str | None = None):
    payload = {
        'controller_active': active_controller_sid is not None,
        'controller_sid': active_controller_sid,
    }
    if to_sid:
        payload['you_are_controller'] = (to_sid == active_controller_sid)
        dj_socketio.emit('controller_status', payload, to=to_sid, namespace='/')
    else:
        # Send individualized payload so each DJ can reliably know whether they are the controller.
        for sid in list(dj_sids):
            dj_socketio.emit(
                'controller_status',
                {
                    **payload,
                    'you_are_controller': (sid == active_controller_sid),
                },
                to=sid,
                namespace='/',
            )


def _deny_if_not_controller() -> bool:
    """Returns True if caller is NOT the controller and was denied."""
    if active_controller_sid is None:
        dj_socketio.emit('error', {'message': 'No active DJ controller. Click Take Control.'}, to=request.sid)
        return True
    if request.sid != active_controller_sid:
        dj_socketio.emit('error', {'message': 'Control is currently held by another DJ'}, to=request.sid)
        return True
    return False


def _sid_identity(sid: str) -> str | None:
    return dj_identity_by_sid.get(sid)


# === Server-side mixer state (authoritative UI sync) ===
def _default_deck_state():
    return {
        'filename': None,
        'duration': 0.0,
        'position': 0.0,
        'playing': False,
        'pitch': 1.0,
        'volume': 0.8,
        'eq': {'low': 0.0, 'mid': 0.0, 'high': 0.0},
        # Internal anchors for time interpolation
        '_started_at': None,
        '_started_pos': 0.0,
    }


mixer_state = {
    'deck_a': _default_deck_state(),
    'deck_b': _default_deck_state(),
    'crossfader': 50,
}


# === Optional MP3 fallback stream (server-side transcoding) ===
# This allows listeners on browsers that don't support WebM/Opus via MediaSource
# (notably some Safari / locked-down environments) to still hear the stream.
_ffmpeg_proc = None
_ffmpeg_in_q = eventlet.queue.LightQueue(maxsize=200)
_mp3_clients = set()  # set[eventlet.queue.LightQueue]
_mp3_lock = threading.Lock()
_transcode_threads_started = False
_transcoder_bytes_out = 0
_transcoder_last_error = None
_last_audio_chunk_ts = 0.0
_remote_stream_url = None  # For relaying remote streams

_mix_restart_timer = None
_mix_restart_lock = threading.Lock()


def _start_transcoder_if_needed():
    global _ffmpeg_proc, _transcode_threads_started

    if _ffmpeg_proc is not None and _ffmpeg_proc.poll() is None:
        return

    def _safe_float(val, default=0.0):
        try:
            return float(val)
        except Exception:
            return float(default)

    def _clamp(val, lo, hi):
        return max(lo, min(hi, val))

    def _deck_runtime_position(d: dict) -> float:
        if not d.get('playing'):
            return _safe_float(d.get('position'), 0.0)
        started_at = d.get('_started_at')
        started_pos = _safe_float(d.get('_started_pos'), _safe_float(d.get('position'), 0.0))
        if started_at is None:
            return _safe_float(d.get('position'), 0.0)
        pitch = _safe_float(d.get('pitch'), 1.0)
        return max(0.0, started_pos + (time.time() - _safe_float(started_at)) * pitch)

    def _ffmpeg_atempo_chain(speed: float) -> str:
        # atempo supports ~[0.5, 2.0] per filter; clamp for now
        s = _clamp(speed, 0.5, 2.0)
        return f"atempo={s:.4f}"

    def _build_server_mix_cmd() -> list[str]:
        # Always include an infinite silent input so ffmpeg never exits.
        silence_src = 'anullsrc=channel_layout=stereo:sample_rate=44100'

        deck_a = mixer_state['deck_a']
        deck_b = mixer_state['deck_b']
        cf = int(mixer_state.get('crossfader', 50))

        # Volumes: crossfader scaling * per-deck volume
        cf_a = (100 - cf) / 100.0
        cf_b = cf / 100.0
        vol_a = _clamp(_safe_float(deck_a.get('volume'), 0.8) * cf_a, 0.0, 1.5)
        vol_b = _clamp(_safe_float(deck_b.get('volume'), 0.8) * cf_b, 0.0, 1.5)

        # Source selection
        def _input_args(deck: dict) -> list[str]:
            fn = deck.get('filename')
            if fn and deck.get('playing'):
                pos = _deck_runtime_position(deck)
                path = os.path.join(os.getcwd(), fn)
                return ['-re', '-ss', f"{pos:.3f}", '-i', path]
            return ['-re', '-f', 'lavfi', '-i', silence_src]

        cmd = [
            'ffmpeg',
            '-hide_banner',
            '-loglevel', 'error',
            *_input_args(deck_a),
            *_input_args(deck_b),
            '-re', '-f', 'lavfi', '-i', silence_src,
        ]

        # Filters per deck
        def _deck_filters(deck: dict, vol: float) -> str:
            parts = [f"volume={vol:.4f}"]

            eq = deck.get('eq') or {}
            low = _clamp(_safe_float(eq.get('low'), 0.0), -20.0, 20.0)
            mid = _clamp(_safe_float(eq.get('mid'), 0.0), -20.0, 20.0)
            high = _clamp(_safe_float(eq.get('high'), 0.0), -20.0, 20.0)
            # Use octave width (o) so it's somewhat musical.
            if abs(low) > 0.001:
                parts.append(f"equalizer=f=320:width_type=o:width=1:g={low:.2f}")
            if abs(mid) > 0.001:
                parts.append(f"equalizer=f=1000:width_type=o:width=1:g={mid:.2f}")
            if abs(high) > 0.001:
                parts.append(f"equalizer=f=3200:width_type=o:width=1:g={high:.2f}")
            return ','.join(parts)

        fc = (
            f"[0:a]{_deck_filters(deck_a, vol_a)}[a0];"
            f"[1:a]{_deck_filters(deck_b, vol_b)}[a1];"
            f"[2:a]volume=0[sil];"
            f"[a0][a1][sil]amix=inputs=3:duration=longest:dropout_transition=0[m]"
        )

        cmd += [
            '-filter_complex', fc,
            '-map', '[m]',
            '-vn',
            '-ac', '2',
            '-ar', '44100',
            '-acodec', 'libmp3lame',
            '-b:a', '192k',
            '-f', 'mp3',
            'pipe:1',
        ]
        return cmd

    if _remote_stream_url:
        cmd = [
            'ffmpeg',
            '-hide_banner',
            '-loglevel', 'error',
            '-re',
            '-i', _remote_stream_url,
            '-vn',
            '-acodec', 'libmp3lame',
            '-b:a', '192k',
            '-f', 'mp3',
            'pipe:1',
        ]
    elif broadcast_state.get('server_mix'):
        cmd = _build_server_mix_cmd()
    else:
        # Local browser-broadcast mode: input from pipe
        cmd = [
            'ffmpeg',
            '-hide_banner',
            '-loglevel', 'error',
            '-i', 'pipe:0',
            '-vn',
            '-acodec', 'libmp3lame',
            '-b:a', '192k',
            '-f', 'mp3',
            'pipe:1',
        ]

    needs_stdin = (not _remote_stream_url) and (not broadcast_state.get('server_mix'))

    try:
        if needs_stdin:
            _ffmpeg_proc = subprocess.Popen(
                cmd,
                stdin=subprocess.PIPE,
                stdout=subprocess.PIPE,
                stderr=subprocess.PIPE,
                bufsize=0,
            )
        else:
            _ffmpeg_proc = subprocess.Popen(
                cmd,
                stdout=subprocess.PIPE,
                stderr=subprocess.PIPE,
                bufsize=0,
            )
    except FileNotFoundError:
        _ffmpeg_proc = None
        print('⚠️ ffmpeg not found; /stream.mp3 fallback disabled')
        return

    mode = 'remote relay' if _remote_stream_url else ('server mix' if broadcast_state.get('server_mix') else 'local broadcast')
    print(f'🎛️ ffmpeg transcoder started for /stream.mp3 ({mode})')

    def _writer():
        global _transcoder_last_error
        while True:
            chunk = _ffmpeg_in_q.get()
            if chunk is None:
                continue
            proc = _ffmpeg_proc
            if proc is None or proc.stdin is None:
                continue
            try:
                proc.stdin.write(chunk)
            except Exception:
                # If ffmpeg dies or pipe breaks, just stop writing.
                _transcoder_last_error = 'stdin write failed'
                break

    def _reader():
        global _transcoder_bytes_out, _transcoder_last_error
        proc = _ffmpeg_proc
        if proc is None or proc.stdout is None:
            return
        while True:
            try:
                data = proc.stdout.read(4096)
            except Exception:
                _transcoder_last_error = 'stdout read failed'
                break
            if not data:
                break
            _transcoder_bytes_out += len(data)
            with _mp3_lock:
                clients = list(_mp3_clients)
            for q in clients:
                try:
                    q.put_nowait(data)
                except Exception:
                    # Drop if client queue is full or gone.
                    pass

    if not _transcode_threads_started:
        eventlet.spawn_n(_writer)
        _transcode_threads_started = True

    eventlet.spawn_n(_reader)


def _stop_transcoder():
    global _ffmpeg_proc
    proc = _ffmpeg_proc
    _ffmpeg_proc = None
    if proc is None:
        return
    try:
        proc.terminate()
    except Exception:
        pass


def _schedule_mix_restart():
    global _mix_restart_timer
    if not broadcast_state.get('active') or not broadcast_state.get('server_mix'):
        return
    if _remote_stream_url:
        return
    with _mix_restart_lock:
        if _mix_restart_timer is not None:
            try:
                _mix_restart_timer.cancel()
            except Exception:
                pass

        def _do():
            # Restart ffmpeg so changes apply.
            _stop_transcoder()
            _start_transcoder_if_needed()

        _mix_restart_timer = eventlet.spawn_after(0.20, _do)


def _feed_transcoder(data: bytes):
    global _last_audio_chunk_ts
    if _ffmpeg_proc is None or _ffmpeg_proc.poll() is not None or _remote_stream_url or broadcast_state.get('server_mix'):
        return
    _last_audio_chunk_ts = time.time()
    try:
        _ffmpeg_in_q.put_nowait(data)
    except Exception:
        # Queue full; drop to keep latency bounded.
        pass
MUSIC_FOLDER = "music"
# Ensure music folder exists
if not os.path.exists(MUSIC_FOLDER):
    os.makedirs(MUSIC_FOLDER)

# Helper for shared routes
def setup_shared_routes(app):
    @app.route('/library.json')
    def get_library():
        library = []
        if os.path.exists(MUSIC_FOLDER):
            for filename in sorted(os.listdir(MUSIC_FOLDER)):
                if filename.lower().endswith(('.mp3', '.m4a', '.wav', '.flac', '.ogg')):
                    library.append({
                        "title": os.path.splitext(filename)[0],
                        "file": f"music/{filename}"
                    })
        return jsonify(library)

    @app.route('/download', methods=['POST'])
    def download():
        data = request.get_json(silent=True) or {}
        url = data.get('url')
        quality = data.get('quality', '320')
        if not url:
            return jsonify({"success": False, "error": "No URL provided"}), 400
        result = downloader.download_mp3(url, quality)
        return jsonify(result)

    @app.route('/search_youtube', methods=['GET'])
    def search_youtube():
        query = request.args.get('q', '')
        if not query:
            return jsonify({"success": False, "error": "No query provided"}), 400
        
        # Get API key from environment variable
        api_key = os.environ.get('YOUTUBE_API_KEY', '')
        if not api_key:
            return jsonify({
                "success": False, 
                "error": "YouTube API key not configured. Set YOUTUBE_API_KEY environment variable."
            }), 500
        
        try:
            import requests
            # Search YouTube using Data API v3
            url = 'https://www.googleapis.com/youtube/v3/search'
            params = {
                'part': 'snippet',
                'q': query,
                'type': 'video',
                'videoCategoryId': '10',  # Music category
                'maxResults': 20,
                'key': api_key
            }
            
            response = requests.get(url, params=params)
            data = response.json()
            
            if 'error' in data:
                return jsonify({
                    "success": False,
                    "error": data['error'].get('message', 'YouTube API error')
                }), 400
            
            # Format results
            results = []
            for item in data.get('items', []):
                results.append({
                    'videoId': item['id']['videoId'],
                    'title': item['snippet']['title'],
                    'channel': item['snippet']['channelTitle'],
                    'thumbnail': item['snippet']['thumbnails']['medium']['url'],
                    'url': f"https://www.youtube.com/watch?v={item['id']['videoId']}"
                })
            
            return jsonify({"success": True, "results": results})
            
        except Exception as e:
            return jsonify({"success": False, "error": str(e)}), 500

    @app.route('/<path:filename>')
    def serve_static(filename):
        response = send_from_directory('.', filename)
        if filename.endswith(('.css', '.js', '.html')):
            response.headers['Cache-Control'] = 'no-store, no-cache, must-revalidate, max-age=0'
        return response

    @app.route('/')
    def index():
        return send_from_directory('.', 'index.html')
    
    @app.route('/upload', methods=['POST'])
    def upload_file():
        if 'file' not in request.files:
            return jsonify({"success": False, "error": "No file provided"}), 400
        
        file = request.files['file']
        
        if file.filename == '':
            return jsonify({"success": False, "error": "No file selected"}), 400
        
        if not file.filename.endswith('.mp3'):
            return jsonify({"success": False, "error": "Only MP3 files are allowed"}), 400
        
        # Sanitize filename (keep extension)
        import re
        name_without_ext = os.path.splitext(file.filename)[0]
        name_without_ext = re.sub(r'[^\w\s-]', '', name_without_ext)
        name_without_ext = re.sub(r'[-\s]+', '-', name_without_ext)
        filename = f"{name_without_ext}.mp3"
        
        filepath = os.path.join(MUSIC_FOLDER, filename)
        
        try:
            file.save(filepath)
            print(f"✅ Uploaded: {filename}")
            return jsonify({"success": True, "filename": filename})
        except Exception as e:
            print(f"❌ Upload error: {e}")
            return jsonify({"success": False, "error": str(e)}), 500

    @app.route('/stream.mp3')
    def stream_mp3():
        # Streaming response from the ffmpeg transcoder output.
        # If ffmpeg isn't available, return 503.
        if _ffmpeg_proc is None or _ffmpeg_proc.poll() is not None:
            return jsonify({"success": False, "error": "MP3 stream not available"}), 503

        client_q = eventlet.queue.LightQueue(maxsize=200)
        with _mp3_lock:
            _mp3_clients.add(client_q)

        def gen():
            try:
                while True:
                    chunk = client_q.get()
                    if chunk is None:
                        break
                    yield chunk
            finally:
                with _mp3_lock:
                    _mp3_clients.discard(client_q)

        return Response(
            stream_with_context(gen()),
            mimetype='audio/mpeg',
            headers={
                'Cache-Control': 'no-store, no-cache, must-revalidate, max-age=0',
                'Connection': 'keep-alive',
            },
        )

    @app.route('/stream_debug')
    def stream_debug():
        proc = _ffmpeg_proc
        running = proc is not None and proc.poll() is None
        return jsonify({
            'broadcast_active': broadcast_state.get('active', False),
            'broadcast_mimeType': broadcast_state.get('mimeType'),
            'ffmpeg_running': running,
            'ffmpeg_found': (proc is not None),
            'mp3_clients': len(_mp3_clients),
            'transcoder_bytes_out': _transcoder_bytes_out,
            'transcoder_last_error': _transcoder_last_error,
            'last_audio_chunk_ts': _last_audio_chunk_ts,
        })

# === DJ SERVER (Port 5000) ===
dj_app = Flask(__name__, static_folder='.', static_url_path='')
dj_app.config['SECRET_KEY'] = 'dj_panel_secret'
setup_shared_routes(dj_app)


@dj_app.before_request
def _protect_dj_panel():
        """Optionally require a password for the DJ panel only (port 5000).

        This does not affect the listener server (port 5001).
        """
        if not DJ_AUTH_ENABLED:
                return None

        # Allow login/logout endpoints
        if request.path in ('/login', '/logout'):
                return None

        # If already authenticated, allow
        if session.get('dj_authed') is True:
                return None

        # Redirect everything else to login
        return (
                "<!doctype html><html><head><meta http-equiv='refresh' content='0; url=/login' /></head>"
                "<body>Redirecting to <a href='/login'>/login</a>...</body></html>",
                302,
                {'Location': '/login'}
        )


@dj_app.route('/login', methods=['GET', 'POST'])
def dj_login():
        if not DJ_AUTH_ENABLED:
                # If auth is disabled, just go to the panel.
                session['dj_authed'] = True
                return (
                        "<!doctype html><html><head><meta http-equiv='refresh' content='0; url=/' /></head>"
                        "<body>Auth disabled. Redirecting...</body></html>",
                        302,
                        {'Location': '/'}
                )

        error = None
        if request.method == 'POST':
                pw = (request.form.get('password') or '').strip()
                if pw == DJ_PANEL_PASSWORD:
                        session['dj_authed'] = True
                        return (
                                "<!doctype html><html><head><meta http-equiv='refresh' content='0; url=/' /></head>"
                                "<body>Logged in. Redirecting...</body></html>",
                                302,
                                {'Location': '/'}
                        )
                error = 'Invalid password'

        # Minimal inline login page (no new assets)
        return f"""<!doctype html>
<html lang=\"en\">
    <head>
        <meta charset=\"utf-8\" />
        <meta name=\"viewport\" content=\"width=device-width, initial-scale=1\" />
        <title>TechDJ - DJ Login</title>
        <style>
            body {{ background:#0a0a12; color:#eee; font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial; margin:0; }}
            .wrap {{ min-height:100vh; display:flex; align-items:center; justify-content:center; padding:24px; }}
            .card {{ width:100%; max-width:420px; background:rgba(10,10,20,0.85); border:2px solid #bc13fe; border-radius:16px; padding:24px; box-shadow:0 0 40px rgba(188,19,254,0.25); }}
            h1 {{ margin:0 0 16px 0; font-size:22px; }}
            label {{ display:block; margin:12px 0 8px; opacity:0.9; }}
            input {{ width:100%; padding:12px; border-radius:10px; border:1px solid rgba(255,255,255,0.15); background:rgba(0,0,0,0.35); color:#fff; }}
            button {{ width:100%; margin-top:14px; padding:12px; border-radius:10px; border:2px solid #bc13fe; background:rgba(188,19,254,0.15); color:#fff; font-weight:700; cursor:pointer; }}
            .err {{ margin-top:12px; color:#ffb3ff; }}
            .hint {{ margin-top:10px; font-size:12px; opacity:0.7; }}
        </style>
    </head>
    <body>
        <div class=\"wrap\">
            <div class=\"card\">
                <h1>DJ Panel Locked</h1>
                <form method=\"post\" action=\"/login\">
                    <label for=\"password\">Password</label>
                    <input id=\"password\" name=\"password\" type=\"password\" autocomplete=\"current-password\" autofocus />
                    <button type=\"submit\">Unlock DJ Panel</button>
                    {f"<div class='err'>{error}</div>" if error else ""}
                    <div class=\"hint\">Set/disable this in config.json (dj_panel_password).</div>
                </form>
            </div>
        </div>
    </body>
</html>"""


@dj_app.route('/logout')
def dj_logout():
        session.pop('dj_authed', None)
        return (
                "<!doctype html><html><head><meta http-equiv='refresh' content='0; url=/login' /></head>"
                "<body>Logged out. Redirecting...</body></html>",
                302,
                {'Location': '/login'}
        )
dj_socketio = SocketIO(
    dj_app, 
    cors_allowed_origins="*", 
    async_mode='eventlet',
    max_http_buffer_size=1e8, # 100MB buffer
    ping_timeout=10, 
    ping_interval=5,
    logger=False,
    engineio_logger=False
)

@dj_socketio.on('connect')
def dj_connect():
    if DJ_AUTH_ENABLED and session.get('dj_authed') is not True:
        print(f"⛔ DJ socket rejected (unauthorized): {request.sid}")
        return False
    print(f"🎧 DJ connected: {request.sid}")
    dj_sids.add(request.sid)

    # Send controller status + current stream status to the new DJ
    _emit_controller_status(to_sid=request.sid)
    dj_socketio.emit('mixer_status', {
        'deck_a': _public_deck_state(mixer_state['deck_a']),
        'deck_b': _public_deck_state(mixer_state['deck_b']),
        'crossfader': mixer_state.get('crossfader', 50),
    }, to=request.sid, namespace='/')
    dj_socketio.emit('stream_status', {
        'active': broadcast_state.get('active', False),
        'remote_relay': bool(broadcast_state.get('remote_relay', False)),
        'server_mix': bool(broadcast_state.get('server_mix', False)),
    }, to=request.sid, namespace='/')

@dj_socketio.on('disconnect')
def dj_disconnect():
    dj_sids.discard(request.sid)
    ident = dj_identity_by_sid.get(request.sid)
    dj_identity_by_sid.pop(request.sid, None)
    global active_controller_sid
    was_controller = (request.sid == active_controller_sid)
    if was_controller:
        global last_controller_identity, last_controller_released_at
        last_controller_identity = ident
        last_controller_released_at = time.time()
        active_controller_sid = None
        print("🧑‍✈️ DJ controller disconnected; control released")
        _emit_controller_status()
    print("⚠️ DJ disconnected - broadcast will continue until manually stopped")


@dj_socketio.on('dj_identity')
def dj_identity(data):
    """Associate a stable client identity with this socket and optionally auto-reclaim control."""
    global active_controller_sid
    ident = (data or {}).get('id')
    auto_reclaim = bool((data or {}).get('auto_reclaim'))
    if not ident or not isinstance(ident, str):
        return
    dj_identity_by_sid[request.sid] = ident

    # Auto-reclaim: only if no controller exists AND you were the last controller.
    if auto_reclaim and active_controller_sid is None:
        if last_controller_identity and ident == last_controller_identity:
            active_controller_sid = request.sid
            print(f"🧑‍✈️ Auto-reclaimed control for identity: {ident}")
            _emit_controller_status()


@dj_socketio.on('take_control')
def dj_take_control():
    global active_controller_sid
    if active_controller_sid is not None and active_controller_sid != request.sid:
        dj_socketio.emit('error', {'message': 'Control is currently held by another DJ'}, to=request.sid)
        _emit_controller_status(to_sid=request.sid)
        return
    active_controller_sid = request.sid
    global last_controller_identity
    last_controller_identity = _sid_identity(request.sid)
    print(f"🧑‍✈️ DJ took control: {request.sid}")
    _emit_controller_status()

def stop_broadcast_after_timeout():
    """No longer used - broadcasts don't auto-stop"""
    pass

@dj_socketio.on('start_broadcast')
def dj_start(data=None):
    if _deny_if_not_controller():
        return
    global _remote_stream_url
    _remote_stream_url = None
    broadcast_state['active'] = True
    broadcast_state['remote_relay'] = False
    broadcast_state['server_mix'] = True
    session['is_dj'] = True
    print("🎙️ Broadcast -> ACTIVE")

    _start_transcoder_if_needed()

    dj_socketio.emit('stream_status', {
        'active': True,
        'remote_relay': False,
        'server_mix': True,
    }, namespace='/')
    
    listener_socketio.emit('broadcast_started', namespace='/')
    listener_socketio.emit('stream_status', {
        'active': True,
        'remote_relay': bool(broadcast_state.get('remote_relay', False)),
        'server_mix': bool(broadcast_state.get('server_mix', False)),
    }, namespace='/')

@dj_socketio.on('stop_broadcast')
def dj_stop():
    if _deny_if_not_controller():
        return
    broadcast_state['active'] = False
    session['is_dj'] = False
    print("🛑 DJ stopped broadcasting")

    broadcast_state['remote_relay'] = False
    broadcast_state['server_mix'] = False

    _stop_transcoder()

    dj_socketio.emit('stream_status', {'active': False, 'remote_relay': False, 'server_mix': False}, namespace='/')
    
    listener_socketio.emit('broadcast_stopped', namespace='/')
    listener_socketio.emit('stream_status', {'active': False, 'remote_relay': False, 'server_mix': False}, namespace='/')

@dj_socketio.on('start_remote_relay')
def dj_start_remote_relay(data):
    if _deny_if_not_controller():
        return
    global _remote_stream_url
    url = data.get('url', '').strip()
    if not url:
        dj_socketio.emit('error', {'message': 'No URL provided for remote relay'})
        return
    
    # Stop any existing broadcast/relay
    if broadcast_state['active']:
        dj_stop()
    
    _remote_stream_url = url
    broadcast_state['active'] = True
    broadcast_state['remote_relay'] = True
    broadcast_state['server_mix'] = False
    session['is_dj'] = True
    print(f"🔗 Starting remote relay from: {url}")
    
    _start_transcoder_if_needed()

    dj_socketio.emit('stream_status', {'active': True, 'remote_relay': True, 'server_mix': False}, namespace='/')
    
    listener_socketio.emit('broadcast_started', namespace='/')
    listener_socketio.emit('stream_status', {'active': True, 'remote_relay': True, 'server_mix': False}, namespace='/')

@dj_socketio.on('stop_remote_relay')
def dj_stop_remote_relay():
    if _deny_if_not_controller():
        return
    global _remote_stream_url
    _remote_stream_url = None
    broadcast_state['active'] = False
    broadcast_state['remote_relay'] = False
    broadcast_state['server_mix'] = False
    session['is_dj'] = False
    print("🛑 Remote relay stopped")

    _stop_transcoder()

    dj_socketio.emit('stream_status', {'active': False, 'remote_relay': False, 'server_mix': False}, namespace='/')
    
    listener_socketio.emit('broadcast_stopped', namespace='/')
    listener_socketio.emit('stream_status', {'active': False, 'remote_relay': False, 'server_mix': False}, namespace='/')

@dj_socketio.on('audio_chunk')
def dj_audio(data):
    # MP3-only mode: do not relay raw chunks to listeners; feed transcoder only.
    if broadcast_state['active'] and not broadcast_state.get('server_mix'):
        # Ensure MP3 fallback transcoder is running (if ffmpeg is installed)
        if _ffmpeg_proc is None or _ffmpeg_proc.poll() is not None:
            _start_transcoder_if_needed()

        if isinstance(data, (bytes, bytearray)):
            _feed_transcoder(bytes(data))

# === LISTENER SERVER (Port 5001) ===
listener_app = Flask(__name__, static_folder='.', static_url_path='')
listener_app.config['SECRET_KEY'] = 'listener_secret'
setup_shared_routes(listener_app)
listener_socketio = SocketIO(
    listener_app, 
    cors_allowed_origins="*", 
    async_mode='eventlet',
    max_http_buffer_size=1e8, # 100MB buffer
    ping_timeout=10, 
    ping_interval=5,
    logger=False,
    engineio_logger=False
)

@listener_socketio.on('connect')
def listener_connect():
    print(f"👂 Listener Socket Connected: {request.sid}")

@listener_socketio.on('disconnect')
def listener_disconnect():
    if request.sid in listener_sids:
        listener_sids.discard(request.sid)
        count = len(listener_sids)
        print(f"❌ Listener left. Total: {count}")
        listener_socketio.emit('listener_count', {'count': count}, namespace='/')
        dj_socketio.emit('listener_count', {'count': count}, namespace='/')

@listener_socketio.on('join_listener')
def listener_join():
    if request.sid not in listener_sids:
        listener_sids.add(request.sid)
        count = len(listener_sids)
        print(f"👂 New listener joined. Total: {count}")
        listener_socketio.emit('listener_count', {'count': count}, namespace='/')
        dj_socketio.emit('listener_count', {'count': count}, namespace='/')
    
    emit('stream_status', {
        'active': broadcast_state.get('active', False),
        'remote_relay': bool(broadcast_state.get('remote_relay', False)),
        'server_mix': bool(broadcast_state.get('server_mix', False)),
    })

@listener_socketio.on('get_listener_count')
def listener_get_count():
    emit('listener_count', {'count': len(listener_sids)})

# DJ Panel Routes (No engine commands needed in local mode)
@dj_socketio.on('get_mixer_status')
def get_mixer_status():
    emit('mixer_status', {
        'deck_a': _public_deck_state(mixer_state['deck_a']),
        'deck_b': _public_deck_state(mixer_state['deck_b']),
        'crossfader': mixer_state.get('crossfader', 50),
    })


def _ffprobe_duration_seconds(path: str) -> float:
    try:
        out = subprocess.check_output(
            ['ffprobe', '-v', 'error', '-show_entries', 'format=duration', '-of', 'default=nw=1:nk=1', path],
            stderr=subprocess.DEVNULL,
        )
        return float(out.decode('utf-8').strip() or 0.0)
    except Exception:
        return 0.0


def _deck_key(deck: str) -> str:
    return 'deck_a' if deck == 'A' else 'deck_b'


def _deck_current_position(d: dict) -> float:
    if not d.get('playing'):
        return float(d.get('position') or 0.0)
    started_at = d.get('_started_at')
    started_pos = float(d.get('_started_pos') or 0.0)
    if started_at is None:
        return float(d.get('position') or 0.0)
    pitch = float(d.get('pitch') or 1.0)
    return max(0.0, started_pos + (time.time() - float(started_at)) * pitch)


def _public_deck_state(d: dict) -> dict:
    out = {k: v for k, v in d.items() if not k.startswith('_')}
    out['position'] = _deck_current_position(d)
    return out


def _broadcast_mixer_status():
    dj_socketio.emit('mixer_status', {
        'deck_a': _public_deck_state(mixer_state['deck_a']),
        'deck_b': _public_deck_state(mixer_state['deck_b']),
        'crossfader': mixer_state.get('crossfader', 50),
    }, namespace='/')
    _schedule_mix_restart()


@dj_socketio.on('audio_load_track')
def audio_load_track(data):
    if _deny_if_not_controller():
        return
    deck = (data or {}).get('deck')
    filename = (data or {}).get('filename')
    if deck not in ('A', 'B') or not filename:
        dj_socketio.emit('error', {'message': 'Invalid load request'}, to=request.sid)
        return
    path = os.path.join(MUSIC_FOLDER, filename)
    if not os.path.exists(path):
        dj_socketio.emit('error', {'message': f'Track not found: {filename}'}, to=request.sid)
        return

    key = _deck_key(deck)
    d = mixer_state[key]
    d['filename'] = f"music/{filename}"
    d['duration'] = _ffprobe_duration_seconds(path)
    d['position'] = 0.0
    d['playing'] = False
    d['_started_at'] = None
    d['_started_pos'] = 0.0
    _broadcast_mixer_status()


@dj_socketio.on('audio_play')
def audio_play(data):
    if _deny_if_not_controller():
        return
    deck = (data or {}).get('deck')
    if deck not in ('A', 'B'):
        return
    d = mixer_state[_deck_key(deck)]
    if not d.get('filename'):
        dj_socketio.emit('error', {'message': f'No track loaded on Deck {deck}'}, to=request.sid)
        return
    # Anchor for interpolation
    d['position'] = _deck_current_position(d)
    d['playing'] = True
    d['_started_at'] = time.time()
    d['_started_pos'] = float(d['position'])
    _broadcast_mixer_status()


@dj_socketio.on('audio_pause')
def audio_pause(data):
    if _deny_if_not_controller():
        return
    deck = (data or {}).get('deck')
    if deck not in ('A', 'B'):
        return
    d = mixer_state[_deck_key(deck)]
    d['position'] = _deck_current_position(d)
    d['playing'] = False
    d['_started_at'] = None
    d['_started_pos'] = float(d['position'])
    _broadcast_mixer_status()


@dj_socketio.on('audio_seek')
def audio_seek(data):
    if _deny_if_not_controller():
        return
    deck = (data or {}).get('deck')
    pos = float((data or {}).get('position') or 0.0)
    if deck not in ('A', 'B'):
        return
    d = mixer_state[_deck_key(deck)]
    d['position'] = max(0.0, pos)
    if d.get('playing'):
        d['_started_at'] = time.time()
        d['_started_pos'] = float(d['position'])
    _broadcast_mixer_status()


@dj_socketio.on('audio_set_volume')
def audio_set_volume(data):
    if _deny_if_not_controller():
        return
    deck = (data or {}).get('deck')
    vol = float((data or {}).get('volume') or 0.0)
    if deck not in ('A', 'B'):
        return
    d = mixer_state[_deck_key(deck)]
    d['volume'] = max(0.0, min(1.0, vol))
    _broadcast_mixer_status()


@dj_socketio.on('audio_set_pitch')
def audio_set_pitch(data):
    if _deny_if_not_controller():
        return
    deck = (data or {}).get('deck')
    pitch = float((data or {}).get('pitch') or 1.0)
    if deck not in ('A', 'B'):
        return
    d = mixer_state[_deck_key(deck)]
    d['pitch'] = max(0.5, min(2.0, pitch))
    # Re-anchor so position interpolation is consistent
    d['position'] = _deck_current_position(d)
    if d.get('playing'):
        d['_started_at'] = time.time()
        d['_started_pos'] = float(d['position'])
    _broadcast_mixer_status()


@dj_socketio.on('audio_set_eq')
def audio_set_eq(data):
    if _deny_if_not_controller():
        return
    deck = (data or {}).get('deck')
    band = (data or {}).get('band')
    value = float((data or {}).get('value') or 0.0)
    if deck not in ('A', 'B'):
        return
    if band not in ('low', 'mid', 'high'):
        return
    d = mixer_state[_deck_key(deck)]
    eq = d.get('eq') or {'low': 0.0, 'mid': 0.0, 'high': 0.0}
    eq[band] = max(-20.0, min(20.0, value))
    d['eq'] = eq
    _broadcast_mixer_status()


@dj_socketio.on('audio_set_crossfader')
def audio_set_crossfader(data):
    if _deny_if_not_controller():
        return
    val = int((data or {}).get('value') or 50)
    mixer_state['crossfader'] = max(0, min(100, val))
    _broadcast_mixer_status()

@dj_socketio.on('audio_sync_queue')
def audio_sync_queue(data):
    pass


if __name__ == '__main__':
    print("=" * 50)
    print("🎧 TECHDJ PRO - DUAL PORT ARCHITECTURE")
    print("=" * 50)
    print("👉 DJ PANEL:    http://localhost:5000")
    print("👉 LISTEN PAGE: http://localhost:5001")
    print("=" * 50)
    
    # Audio engine DISABLED
    print("✅ Local Radio server ready")
    
    # Run both servers using eventlet's spawn
    eventlet.spawn(dj_socketio.run, dj_app, host='0.0.0.0', port=5000, debug=False)
    listener_socketio.run(listener_app, host='0.0.0.0', port=5001, debug=False)