#!/usr/bin/env python3
# -*- coding: utf-8 -*-

from datetime import datetime, timedelta

import pymysql
import qbittorrentapi
import bencodepy

from EmailMessagingGraph import send_mail


# ==============================
# ⚙ CONFIGURATION
# ==============================

DB_CONFIG = {
    "host": "192.168.1.76",
    "port": 3307,
    "user": "root",
    "password": "Vlado9674+",
    "database": "torrents",
    "charset": "utf8mb4",
    "autocommit": True,
}

QBT_CONFIG = {
    "host": "192.168.1.76",
    "port": 8080,
    "username": "admin",
    "password": "adminadmin",
}

MAX_ACTIVE_DOWNLOADS = 10
DEAD_TORRENT_MINUTES = 60
DEFAULT_SAVE_PATH = None

MAIL_TO = "vladimir.buzalka@buzalka.cz"

MAX_LIST_ITEMS = 50  # cap lists in email


# ==============================
# 🧮 RUNTIME STATS + LISTS
# ==============================

RUN_START = datetime.now()

stat_synced = 0
stat_completed = 0
stat_dead = 0
stat_enqueued = 0

deleted_completed = []  # list[str]
deleted_dead = []       # list[str]
added_new = []          # list[str]
active_downloading = [] # list[str]


# ==============================
# 🔧 CONNECT
# ==============================

db = pymysql.connect(**DB_CONFIG)
cursor = db.cursor(pymysql.cursors.DictCursor)

qb = qbittorrentapi.Client(**QBT_CONFIG)

try:
    qb.auth_log_in()
    print("✅ Connected to qBittorrent.")
except Exception as e:
    raise SystemExit(f"❌ Could not connect to qBittorrent: {e}")


# ==============================
# 🧪 TORRENT VALIDATION
# ==============================

def is_valid_torrent(blob: bytes) -> bool:
    try:
        data = bencodepy.decode(blob)
        return isinstance(data, dict) and b"info" in data
    except Exception:
        return False


# ==============================
# 🔄 SYNC FROM QB → DB
# ==============================

def sync_qb_to_db():
    global stat_synced

    torrents = qb.torrents_info()
    stat_synced = len(torrents)

    for t in torrents:
        completion_dt = None
        if getattr(t, "completion_on", 0):
            try:
                completion_dt = datetime.fromtimestamp(t.completion_on)
            except Exception:
                pass

        cursor.execute("""
            UPDATE torrents
            SET qb_added = 1,
                qb_hash = COALESCE(qb_hash, %s),
                qb_state = %s,
                qb_progress = %s,
                qb_savepath = %s,
                qb_completed_datetime =
                    IF(%s IS NOT NULL AND qb_completed_datetime IS NULL, %s, qb_completed_datetime),
                qb_last_update = NOW()
            WHERE qb_hash = %s OR torrent_hash = %s
        """, (
            t.hash,
            t.state,
            float(t.progress) * 100.0,
            getattr(t, "save_path", None),
            completion_dt,
            completion_dt,
            t.hash,
            t.hash,
        ))


# ==============================
# 🧹 HANDLE COMPLETED + DEAD
# ==============================

def handle_completed_and_dead():
    global stat_completed, stat_dead

    torrents = qb.torrents_info()

    for t in torrents:
        t_hash = t.hash
        state = t.state
        progress = float(t.progress)

        # ✔ COMPLETED
        if progress >= 1.0 or state in {"completed", "uploading", "stalledUP", "queuedUP"}:
            stat_completed += 1
            deleted_completed.append(t.name)

            try:
                qb.torrents_delete(torrent_hashes=t_hash, delete_files=False)
            except Exception as e:
                # keep name in report; just note error in DB state if you want later
                print(f"⚠️ delete (keep data) failed for {t.name}: {e}")

            cursor.execute("""
                UPDATE torrents
                SET qb_state='completed',
                    qb_progress=100,
                    qb_completed_datetime=NOW(),
                    qb_last_update=NOW()
                WHERE qb_hash=%s OR torrent_hash=%s
            """, (t_hash, t_hash))
            continue

        # ❌ DEAD (never seen_complete)
        try:
            props = qb.torrents_properties(t_hash)
        except Exception:
            continue

        if getattr(props, "last_seen", 0) == -1:
            added_dt = getattr(t, "added_on", 0)
            if added_dt:
                if datetime.now() - datetime.fromtimestamp(added_dt) > timedelta(minutes=DEAD_TORRENT_MINUTES):
                    stat_dead += 1
                    deleted_dead.append(t.name)

                    try:
                        qb.torrents_delete(torrent_hashes=t_hash, delete_files=True)
                    except Exception as e:
                        print(f"⚠️ delete (files) failed for {t.name}: {e}")

                    cursor.execute("""
                        UPDATE torrents
                        SET qb_state='dead',
                            qb_last_update=NOW()
                        WHERE qb_hash=%s OR torrent_hash=%s
                    """, (t_hash, t_hash))


# ==============================
# 📊 ACTIVE DOWNLOADS
# ==============================

def count_active_downloads():
    return sum(1 for t in qb.torrents_info() if float(t.progress) < 1.0)


def snapshot_active_downloading():
    """
    Capture current actively downloading torrents (progress < 100%).
    """
    active = []
    for t in qb.torrents_info():
        prog = float(t.progress)
        if prog < 1.0:
            active.append(f"{t.name} — {prog*100:.1f}% — {t.state}")
    return sorted(active)


# ==============================
# ➕ ENQUEUE NEW TORRENTS
# ==============================

def enqueue_new_torrents():
    global stat_enqueued

    active = count_active_downloads()
    if active >= MAX_ACTIVE_DOWNLOADS:
        return

    slots = MAX_ACTIVE_DOWNLOADS - active

    cursor.execute("""
        SELECT id, torrent_hash, torrent_content, torrent_filename
        FROM torrents
        WHERE (qb_added IS NULL OR qb_added = 0)
          AND torrent_content IS NOT NULL
        ORDER BY added_datetime DESC
        LIMIT %s
    """, (slots,))

    for row in cursor.fetchall():
        blob = row["torrent_content"]
        if not blob:
            continue

        if not is_valid_torrent(blob):
            cursor.execute("""
                UPDATE torrents
                SET qb_state='invalid',
                    torrent_content=NULL,
                    qb_last_update=NOW()
                WHERE id=%s
            """, (row["id"],))
            continue

        # ➕ Add torrent
        try:
            qb.torrents_add(torrent_files=blob, savepath=DEFAULT_SAVE_PATH)
        except Exception as e:
            print(f"❌ Failed to add {row['torrent_hash']}: {e}")
            continue

        stat_enqueued += 1
        added_new.append(row.get("torrent_filename") or row["torrent_hash"])

        cursor.execute("""
            UPDATE torrents
            SET qb_added=1,
                qb_hash=COALESCE(qb_hash, %s),
                qb_state='added',
                qb_last_update=NOW()
            WHERE id=%s
        """, (row["torrent_hash"], row["id"]))


# ==============================
# ✉️ EMAIL HELPERS
# ==============================

def format_list(title: str, items: list[str]) -> list[str]:
    lines = []
    if not items:
        return [f"{title}: (none)"]

    lines.append(f"{title}: {len(items)}")
    shown = items[:MAX_LIST_ITEMS]
    for it in shown:
        lines.append(f"  - {it}")
    if len(items) > MAX_LIST_ITEMS:
        lines.append(f"  ... (+{len(items) - MAX_LIST_ITEMS} more)")
    return lines


# ==============================
# 🏁 MAIN (ONE RUN)
# ==============================

print("🚀 QB worker run started")

try:
    sync_qb_to_db()
    handle_completed_and_dead()
    enqueue_new_torrents()

    # Snapshot after enqueue/deletions, so email reflects end-state
    active_downloading = snapshot_active_downloading()

finally:
    db.close()


# ==============================
# 📧 EMAIL REPORT
# ==============================

RUN_END = datetime.now()

body_lines = [
    f"Run started : {RUN_START:%Y-%m-%d %H:%M:%S}",
    f"Run finished: {RUN_END:%Y-%m-%d %H:%M:%S}",
    "",
    f"QB torrents synced : {stat_synced}",
    f"Completed removed  : {stat_completed}",
    f"Dead removed       : {stat_dead}",
    f"New torrents added : {stat_enqueued}",
    f"Active downloads   : {sum(1 for _ in active_downloading)}",
    "",
]

body_lines += format_list("Deleted (completed, kept data)", deleted_completed)
body_lines.append("")
body_lines += format_list("Deleted (dead, deleted files)", deleted_dead)
body_lines.append("")
body_lines += format_list("Newly added to qBittorrent", added_new)
body_lines.append("")
body_lines += format_list("Actively downloading now", active_downloading)

send_mail(
    to=MAIL_TO,
    subject=f"qBittorrent worker – {RUN_START:%Y-%m-%d %H:%M}",
    body="\n".join(body_lines),
    html=False,
)

print("📧 Email report sent")
print("🎉 DONE")