import io
import json
import os
import shutil
import subprocess
import threading
import time
import uuid
import zipfile
from pathlib import Path

from utils import rename_from_metadata, sanitize_filename, cleanup_empty_dirs

from flask import (
    Flask,
    jsonify,
    redirect,
    render_template,
    request,
    send_from_directory,
    session,
    url_for,
)

app = Flask(__name__)
app.secret_key = os.environ.get("SECRET_KEY", os.urandom(32).hex())

# Auth
APP_PASSWORD = os.environ.get("PASSWORD", "")


@app.before_request
def require_login():
    if not APP_PASSWORD:
        return
    if request.endpoint in ("login", "static", "service_worker", "offline"):
        return
    if not session.get("authenticated"):
        if request.path.startswith("/api/"):
            return jsonify({"error": "Unauthorized"}), 401
        return redirect(url_for("login"))


# Paths
DOWNLOADS_DIR = Path(os.environ.get("DOWNLOADS_DIR", "/downloads"))
COOKIES_PATH = Path(os.environ.get("COOKIES_PATH", "/config/cookies.txt"))
CONFIG_DIR = Path(os.environ.get("CONFIG_DIR", "/config"))
WVD_PATH = Path(os.environ.get("WVD_PATH", "/config/device.wvd"))
TEMP_DIR = Path("/tmp/votify")

DOWNLOADS_DIR.mkdir(parents=True, exist_ok=True)
TEMP_DIR.mkdir(parents=True, exist_ok=True)

# In-memory job tracking
jobs: dict[str, dict] = {}
jobs_lock = threading.Lock()


def snapshot_audio_files(directory: Path) -> set[Path]:
    extensions = {".m4a", ".ogg", ".opus"}
    files = set()
    for ext in extensions:
        files.update(directory.rglob(f"*{ext}"))
    return files


def convert_to_mp3(job_id: str, before: set[Path]):
    after = snapshot_audio_files(DOWNLOADS_DIR)
    new_files = after - before
    if not new_files:
        return

    def log(msg):
        with jobs_lock:
            jobs[job_id]["output"] = jobs[job_id].get("output", [])[-500:] + [msg]

    log(f"[mp3] Converting {len(new_files)} file(s) to MP3...")
    for src in sorted(new_files):
        dst = src.with_suffix(".mp3")
        log(f"[mp3] Converting: {src.name}")
        result = subprocess.run(
            ["ffmpeg", "-y", "-i", str(src), "-codec:v", "copy", "-q:a", "2", str(dst)],
            capture_output=True, text=True,
        )
        if result.returncode == 0:
            src.unlink()
            log(f"[mp3] Done: {dst.name}")
        else:
            log(f"[mp3] Failed: {src.name} - {result.stderr.strip()[-200:]}")

    log("[mp3] Conversion complete.")


AUDIO_EXTS = {".m4a", ".ogg", ".opus", ".mp3", ".flac"}


def post_process_votify_files(target_dir, job_id):
    """Flatten subdirs, rename files from metadata, wrap single tracks."""
    target_dir = Path(target_dir)

    def log(msg):
        with jobs_lock:
            jobs[job_id]["output"] = jobs[job_id].get("output", [])[-500:] + [msg]

    # 1. Move any files in subdirectories up to target_dir
    for ext in AUDIO_EXTS:
        for f in list(target_dir.rglob(f"*{ext}")):
            if f.parent != target_dir:
                dest = target_dir / f.name
                counter = 2
                while dest.exists():
                    dest = target_dir / f"{f.stem} ({counter}){f.suffix}"
                    counter += 1
                shutil.move(str(f), str(dest))

    # 2. Rename from metadata
    renamed = []
    for ext in AUDIO_EXTS:
        for f in list(target_dir.glob(f"*{ext}")):
            new_path = rename_from_metadata(f)
            renamed.append(new_path)
            if new_path != f:
                log(f"[post] Renamed: {new_path.name}")

    # 3. Clean up empty subdirs
    cleanup_empty_dirs(target_dir)

    # 4. Single-track wrapping (only if downloading to root downloads dir)
    if len(renamed) == 1 and target_dir == DOWNLOADS_DIR:
        f = renamed[0]
        folder_name = sanitize_filename(f.stem)
        wrapper = target_dir / folder_name
        wrapper.mkdir(exist_ok=True)
        shutil.move(str(f), str(wrapper / f.name))
        log(f"[post] Wrapped single track in folder: {folder_name}")

    return renamed


def run_download(job_id: str, urls: list[str], options: dict, output_path: str = None):
    cmd = ["votify"]

    cmd.extend(["--cookies-path", str(COOKIES_PATH)])
    cmd.extend(["--output-path", output_path or str(DOWNLOADS_DIR)])
    cmd.extend(["--temp-path", str(TEMP_DIR)])
    if WVD_PATH.exists():
        cmd.extend(["--wvd-path", str(WVD_PATH)])

    # Flatten folder structure — no nested Artist/Album subdirectories
    cmd.extend(["--template-folder-album", "."])
    cmd.extend(["--template-folder-compilation", "."])
    cmd.extend(["--template-folder-episode", "."])
    cmd.extend(["--template-folder-music-video", "."])

    quality = options.get("audio_quality", "aac-medium")
    if quality:
        cmd.extend(["--audio-quality", quality])

    download_mode = options.get("download_mode", "ytdlp")
    if download_mode:
        cmd.extend(["--download-mode", download_mode])

    video_format = options.get("video_format", "mp4")
    if video_format:
        cmd.extend(["--video-format", video_format])

    cover_size = options.get("cover_size", "large")
    if cover_size:
        cmd.extend(["--cover-size", cover_size])

    if options.get("save_cover"):
        cmd.append("--save-cover")

    if options.get("save_playlist"):
        cmd.append("--save-playlist")

    if options.get("overwrite"):
        cmd.append("--overwrite")

    if options.get("download_music_videos"):
        cmd.append("--download-music-videos")

    if options.get("save_lrc"):
        cmd.append("--lrc-only")

    if options.get("no_lrc"):
        cmd.append("--no-lrc")

    truncate = options.get("truncate")
    if truncate:
        cmd.extend(["--truncate", str(truncate)])

    cmd.extend(urls)

    want_mp3 = options.get("output_format") == "mp3"
    files_before = snapshot_audio_files(DOWNLOADS_DIR) if want_mp3 else None

    with jobs_lock:
        jobs[job_id]["status"] = "running"
        jobs[job_id]["command"] = " ".join(cmd)

    try:
        process = subprocess.Popen(
            cmd,
            stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT,
            text=True,
            bufsize=1,
        )
        with jobs_lock:
            jobs[job_id]["process"] = process

        output_lines = []
        for line in process.stdout:
            with jobs_lock:
                if jobs[job_id]["status"] == "cancelled":
                    break
            line = line.rstrip("\n")
            output_lines.append(line)
            with jobs_lock:
                jobs[job_id]["output"] = output_lines[-500:]

        process.wait()

        with jobs_lock:
            cancelled = jobs[job_id]["status"] == "cancelled"

        if cancelled:
            with jobs_lock:
                jobs[job_id]["output"] = jobs[job_id].get("output", []) + ["[cancelled] Job was cancelled by user."]
        else:
            if process.returncode == 0:
                target = Path(output_path) if output_path else DOWNLOADS_DIR
                post_process_votify_files(target, job_id)
                if want_mp3:
                    convert_to_mp3(job_id, files_before)
            with jobs_lock:
                jobs[job_id]["status"] = "completed" if process.returncode == 0 else "failed"
                jobs[job_id]["return_code"] = process.returncode
    except Exception as e:
        with jobs_lock:
            jobs[job_id]["status"] = "failed"
            jobs[job_id]["output"] = jobs[job_id].get("output", []) + [str(e)]


@app.route("/sw.js")
def service_worker():
    return send_from_directory("static", "sw.js", mimetype="application/javascript")


@app.route("/offline")
def offline():
    return send_from_directory("static", "offline.html")


@app.route("/login", methods=["GET", "POST"])
def login():
    if request.method == "POST":
        password = request.form.get("password", "")
        if password == APP_PASSWORD:
            session["authenticated"] = True
            return redirect(url_for("index"))
        return render_template("login.html", error="Incorrect password")
    return render_template("login.html", error=None)


@app.route("/logout")
def logout():
    session.clear()
    return redirect(url_for("login"))


@app.route("/")
def index():
    return render_template("index.html", auth_enabled=bool(APP_PASSWORD))


@app.route("/api/download", methods=["POST"])
def start_download():
    data = request.json
    urls = [u.strip() for u in data.get("urls", "").split("\n") if u.strip()]
    if not urls:
        return jsonify({"error": "No URLs provided"}), 400

    if not COOKIES_PATH.exists():
        return jsonify({"error": "cookies.txt not found. Mount it to /config/cookies.txt"}), 400

    options = {
        "audio_quality": data.get("audio_quality", "aac-medium"),
        "download_mode": data.get("download_mode", "ytdlp"),
        "video_format": data.get("video_format", "mp4"),
        "cover_size": data.get("cover_size", "large"),
        "save_cover": data.get("save_cover", False),
        "save_playlist": data.get("save_playlist", False),
        "overwrite": data.get("overwrite", False),
        "download_music_videos": data.get("download_music_videos", False),
        "save_lrc": data.get("save_lrc", False),
        "no_lrc": data.get("no_lrc", False),
        "truncate": data.get("truncate"),
        "output_format": data.get("output_format", "original"),
    }

    job_id = str(uuid.uuid4())[:8]
    with jobs_lock:
        jobs[job_id] = {
            "id": job_id,
            "urls": urls,
            "options": options,
            "status": "queued",
            "output": [],
            "created_at": time.time(),
        }

    thread = threading.Thread(target=run_download, args=(job_id, urls, options), daemon=True)
    thread.start()

    return jsonify({"job_id": job_id})


def run_monochrome_download(job_id: str, url: str, quality: str):
    with jobs_lock:
        jobs[job_id]["status"] = "running"

    def log(msg):
        with jobs_lock:
            jobs[job_id]["output"] = jobs[job_id].get("output", [])[-500:] + [msg]

    def is_cancelled():
        with jobs_lock:
            return jobs[job_id]["status"] == "cancelled"

    try:
        from monochrome.api import download_spotify_url
        success, total, fail_info = download_spotify_url(
            spotify_url=url,
            quality=quality,
            output_dir=str(DOWNLOADS_DIR),
            log=log,
            cancel_check=is_cancelled,
        )
        with jobs_lock:
            if jobs[job_id]["status"] != "cancelled":
                jobs[job_id]["status"] = "completed" if success > 0 else "failed"
                jobs[job_id]["return_code"] = 0 if success > 0 else 1
    except Exception as e:
        with jobs_lock:
            jobs[job_id]["status"] = "failed"
            jobs[job_id]["output"] = jobs[job_id].get("output", []) + [f"[error] {e}"]
            jobs[job_id]["return_code"] = 1


@app.route("/api/monochrome/download", methods=["POST"])
def start_monochrome_download():
    data = request.json
    url = data.get("url", "").strip()
    quality = data.get("quality", "HI_RES_LOSSLESS")

    if not url:
        return jsonify({"error": "No URL provided"}), 400

    valid_qualities = ["HI_RES_LOSSLESS", "LOSSLESS", "HIGH", "LOW", "MP3_320"]
    if quality not in valid_qualities:
        return jsonify({"error": f"Invalid quality. Choose from: {valid_qualities}"}), 400

    job_id = str(uuid.uuid4())[:8]
    with jobs_lock:
        jobs[job_id] = {
            "id": job_id,
            "urls": [url],
            "options": {"quality": quality, "source": "monochrome"},
            "status": "queued",
            "output": [],
            "created_at": time.time(),
        }

    thread = threading.Thread(
        target=run_monochrome_download, args=(job_id, url, quality), daemon=True
    )
    thread.start()

    return jsonify({"job_id": job_id})


# --- Unified download (Monochrome → Votify fallback) ---

SETTINGS_PATH = CONFIG_DIR / "settings.json"


def load_settings():
    if SETTINGS_PATH.exists():
        try:
            return json.loads(SETTINGS_PATH.read_text())
        except (json.JSONDecodeError, OSError):
            pass
    return {"fallback_quality": "aac-medium"}


def run_unified_download(job_id: str, url: str):
    with jobs_lock:
        jobs[job_id]["status"] = "running"

    def log(msg):
        with jobs_lock:
            jobs[job_id]["output"] = jobs[job_id].get("output", [])[-500:] + [msg]

    def is_cancelled():
        with jobs_lock:
            return jobs[job_id]["status"] == "cancelled"

    try:
        from monochrome.api import download_spotify_url
        success, total, fail_info = download_spotify_url(
            spotify_url=url,
            quality="MP3_320",
            output_dir=str(DOWNLOADS_DIR),
            log=log,
            cancel_check=is_cancelled,
        )
        with jobs_lock:
            if jobs[job_id]["status"] != "cancelled":
                jobs[job_id]["status"] = "completed" if success > 0 else "failed"
                jobs[job_id]["return_code"] = 0 if success > 0 else 1
    except Exception as e:
        with jobs_lock:
            jobs[job_id]["status"] = "failed"
            jobs[job_id]["output"] = jobs[job_id].get("output", []) + [f"[error] {e}"]
            jobs[job_id]["return_code"] = 1
        return

    # Check if we should spawn Votify fallback
    with jobs_lock:
        cancelled = jobs[job_id]["status"] == "cancelled"

    failed_urls = fail_info.get("failed_urls", [])
    if cancelled or not failed_urls:
        return

    # Spawn Votify fallback job for failed tracks
    settings = load_settings()
    fallback_quality = settings.get("fallback_quality", "aac-medium")

    subfolder = fail_info.get("subfolder")
    output_path = str(DOWNLOADS_DIR / subfolder) if subfolder else str(DOWNLOADS_DIR)

    votify_job_id = str(uuid.uuid4())[:8]
    with jobs_lock:
        jobs[votify_job_id] = {
            "id": votify_job_id,
            "urls": failed_urls,
            "options": {"audio_quality": fallback_quality, "source": "votify-fallback"},
            "status": "queued",
            "output": [],
            "created_at": time.time(),
        }

    log(f"[monochrome] {len(failed_urls)} track(s) failed — starting Votify fallback (job {votify_job_id})")

    run_download(votify_job_id, failed_urls, {
        "audio_quality": fallback_quality,
        "output_format": "mp3",
    }, output_path=output_path)


@app.route("/api/unified/download", methods=["POST"])
def start_unified_download():
    data = request.json
    url = data.get("url", "").strip()

    if not url:
        return jsonify({"error": "No URL provided"}), 400

    job_id = str(uuid.uuid4())[:8]
    with jobs_lock:
        jobs[job_id] = {
            "id": job_id,
            "urls": [url],
            "options": {"source": "unified"},
            "status": "queued",
            "output": [],
            "created_at": time.time(),
        }

    thread = threading.Thread(
        target=run_unified_download, args=(job_id, url), daemon=True
    )
    thread.start()

    return jsonify({"job_id": job_id})


@app.route("/api/settings", methods=["GET"])
def get_settings():
    return jsonify(load_settings())


@app.route("/api/settings", methods=["POST"])
def save_settings():
    data = request.json
    allowed_qualities = ["aac-medium", "aac-high"]
    quality = data.get("fallback_quality", "aac-medium")
    if quality not in allowed_qualities:
        quality = "aac-medium"
    settings = {"fallback_quality": quality}
    CONFIG_DIR.mkdir(parents=True, exist_ok=True)
    SETTINGS_PATH.write_text(json.dumps(settings))
    return jsonify({"ok": True})


def job_to_dict(job):
    return {k: v for k, v in job.items() if k != "process"}


@app.route("/api/jobs")
def list_jobs():
    with jobs_lock:
        return jsonify([job_to_dict(j) for j in jobs.values()])


@app.route("/api/jobs/<job_id>")
def get_job(job_id):
    with jobs_lock:
        job = jobs.get(job_id)
    if not job:
        return jsonify({"error": "Job not found"}), 404
    return jsonify(job_to_dict(job))


@app.route("/api/jobs/<job_id>/cancel", methods=["POST"])
def cancel_job(job_id):
    with jobs_lock:
        job = jobs.get(job_id)
        if not job:
            return jsonify({"error": "Job not found"}), 404
        if job["status"] != "running":
            return jsonify({"error": "Job is not running"}), 400
        job["status"] = "cancelled"
        proc = job.get("process")
    if proc:
        proc.terminate()
    return jsonify({"ok": True})


@app.route("/api/jobs/<job_id>", methods=["DELETE"])
def delete_job(job_id):
    with jobs_lock:
        if job_id in jobs:
            del jobs[job_id]
    return jsonify({"ok": True})


@app.route("/api/files")
def list_files():
    rel_path = request.args.get("path", "")
    target = DOWNLOADS_DIR / rel_path
    if not target.exists():
        return jsonify([])

    items = []
    try:
        for entry in sorted(target.iterdir(), key=lambda e: (not e.is_dir(), e.name.lower())):
            rel = entry.relative_to(DOWNLOADS_DIR)
            items.append({
                "name": entry.name,
                "path": str(rel).replace("\\", "/"),
                "is_dir": entry.is_dir(),
                "size": entry.stat().st_size if entry.is_file() else None,
            })
    except PermissionError:
        pass
    return jsonify(items)


@app.route("/api/files/download")
def download_file():
    rel_path = request.args.get("path", "")
    target = DOWNLOADS_DIR / rel_path
    if not target.is_file():
        return jsonify({"error": "File not found"}), 404
    return send_from_directory(target.parent, target.name, as_attachment=True)


@app.route("/api/files/download-folder")
def download_folder():
    rel_path = request.args.get("path", "")
    target = DOWNLOADS_DIR / rel_path
    if not target.is_dir():
        return jsonify({"error": "Folder not found"}), 404

    buf = io.BytesIO()
    with zipfile.ZipFile(buf, "w", zipfile.ZIP_DEFLATED) as zf:
        for file in target.rglob("*"):
            if file.is_file():
                zf.write(file, file.relative_to(target))
    buf.seek(0)

    folder_name = target.name or "downloads"
    return app.response_class(
        buf.getvalue(),
        mimetype="application/zip",
        headers={"Content-Disposition": f'attachment; filename="{folder_name}.zip"'},
    )


@app.route("/api/files/delete", methods=["DELETE"])
def delete_path():
    rel_path = request.args.get("path", "")
    if not rel_path:
        return jsonify({"error": "Cannot delete root"}), 400
    target = DOWNLOADS_DIR / rel_path
    if not target.exists():
        return jsonify({"error": "Not found"}), 404
    if not str(target.resolve()).startswith(str(DOWNLOADS_DIR.resolve())):
        return jsonify({"error": "Invalid path"}), 403
    try:
        if target.is_dir():
            shutil.rmtree(target)
        else:
            target.unlink()
    except Exception as e:
        return jsonify({"error": str(e)}), 500
    return jsonify({"ok": True})


@app.route("/api/cookies", methods=["GET"])
def check_cookies():
    return jsonify({"exists": COOKIES_PATH.exists()})


@app.route("/api/cookies", methods=["POST"])
def upload_cookies():
    if "file" not in request.files:
        return jsonify({"error": "No file uploaded"}), 400
    file = request.files["file"]
    CONFIG_DIR.mkdir(parents=True, exist_ok=True)
    file.save(COOKIES_PATH)
    return jsonify({"ok": True})


@app.route("/api/wvd", methods=["GET"])
def check_wvd():
    return jsonify({"exists": WVD_PATH.exists()})


@app.route("/api/wvd", methods=["POST"])
def upload_wvd():
    if "file" not in request.files:
        return jsonify({"error": "No file uploaded"}), 400
    file = request.files["file"]
    CONFIG_DIR.mkdir(parents=True, exist_ok=True)
    file.save(WVD_PATH)
    return jsonify({"ok": True})


if __name__ == "__main__":
    app.run(host="0.0.0.0", port=5000, debug=False)