from __future__ import annotations

import json
from datetime import datetime, timedelta, timezone
from typing import Any
from ..db import connect, utcnow, default_user_id
from . import auth, rtorrent

DEFAULT_SETTINGS = {"retention_mode": "days", "retention_days": 30, "retention_lines": 5000}
VALID_RETENTION_MODES = {"days", "lines", "both", "manual"}


def _user_id(user_id: int | None = None) -> int:
    return int(user_id or auth.current_user_id() or default_user_id())


def _details(value: dict | None = None) -> str:
    try:
        return json.dumps(value or {}, ensure_ascii=False, sort_keys=True)
    except Exception:
        return "{}"


def _row_to_public(row: dict) -> dict:
    item = dict(row)
    try:
        item["details"] = json.loads(item.get("details_json") or "{}")
    except Exception:
        item["details"] = {}
    item["details_h"] = ", ".join(f"{k}: {v}" for k, v in item["details"].items() if v not in (None, ""))
    return item


def get_settings(profile_id: int = 0, user_id: int | None = None) -> dict:
    user_id = _user_id(user_id)
    profile_id = int(profile_id or 0)
    with connect() as conn:
        row = conn.execute(
            "SELECT * FROM operation_log_settings WHERE user_id=? AND profile_id=?",
            (user_id, profile_id),
        ).fetchone()
    if not row:
        return {"user_id": user_id, "profile_id": profile_id, **DEFAULT_SETTINGS}
    data = {**DEFAULT_SETTINGS, **dict(row)}
    data["retention_mode"] = data.get("retention_mode") if data.get("retention_mode") in VALID_RETENTION_MODES else "days"
    data["retention_days"] = max(1, int(data.get("retention_days") or DEFAULT_SETTINGS["retention_days"]))
    data["retention_lines"] = max(100, int(data.get("retention_lines") or DEFAULT_SETTINGS["retention_lines"]))
    return data


def save_settings(profile_id: int, data: dict, user_id: int | None = None) -> dict:
    user_id = _user_id(user_id)
    profile_id = int(profile_id or 0)
    mode = str(data.get("retention_mode") or "days").lower()
    if mode not in VALID_RETENTION_MODES:
        mode = "days"
    days = max(1, min(3650, int(data.get("retention_days") or DEFAULT_SETTINGS["retention_days"])))
    lines = max(100, min(1_000_000, int(data.get("retention_lines") or DEFAULT_SETTINGS["retention_lines"])))
    now = utcnow()
    with connect() as conn:
        conn.execute(
            """
            INSERT INTO operation_log_settings(user_id, profile_id, retention_mode, retention_days, retention_lines, created_at, updated_at)
            VALUES(?,?,?,?,?,?,?)
            ON CONFLICT(user_id, profile_id) DO UPDATE SET
              retention_mode=excluded.retention_mode,
              retention_days=excluded.retention_days,
              retention_lines=excluded.retention_lines,
              updated_at=excluded.updated_at
            """,
            (user_id, profile_id, mode, days, lines, now, now),
        )
    return get_settings(profile_id, user_id)


def record(profile_id: int | None, event_type: str, message: str, *, severity: str = "info", source: str = "system", torrent_hash: str | None = None, torrent_name: str | None = None, action: str | None = None, details: dict | None = None, user_id: int | None = None) -> int:
    now = utcnow()
    user_id = _user_id(user_id)
    with connect() as conn:
        cur = conn.execute(
            """
            INSERT INTO operation_logs(user_id, profile_id, event_type, severity, source, torrent_hash, torrent_name, action, message, details_json, created_at)
            VALUES(?,?,?,?,?,?,?,?,?,?,?)
            """,
            (user_id, int(profile_id or 0) or None, str(event_type), str(severity or "info"), str(source or "system"), torrent_hash, torrent_name, action, str(message), _details(details), now),
        )
        return int(cur.lastrowid)


def record_job_event(profile_id: int, action: str, status: str, payload: dict | None, result: dict | None = None, error: str = "", job_id: str | None = None, user_id: int | None = None) -> None:
    payload = payload or {}
    result = result or {}
    hashes = payload.get("hashes") or []
    ctx = payload.get("job_context") or {}
    items = ctx.get("items") or []
    by_hash = {str(item.get("hash")): item for item in items if item}
    event_type = "job_done" if status == "done" else "job_failed" if status == "failed" else "job_started"
    severity = "danger" if status == "failed" else "info"
    if action in {"add_magnet", "add_torrent_raw"}:
        name = str(payload.get("name") or payload.get("filename") or payload.get("uri") or "torrent")[:300]
        msg = f"{action} {status}: {name}"
        record(profile_id, "torrent_added" if status == "done" else event_type, msg, severity=severity, source="job", action=action, details={"job_id": job_id, "status": status, "directory": payload.get("directory"), "label": payload.get("label"), "error": error, "result": result}, user_id=user_id)
        return
    if not hashes:
        record(profile_id, event_type, f"{action} {status}", severity=severity, source="job", action=action, details={"job_id": job_id, "status": status, "error": error, "result": result}, user_id=user_id)
        return
    for h in hashes:
        item = by_hash.get(str(h)) or {}
        name = str(item.get("name") or h)
        record(profile_id, "torrent_removed" if action == "remove" and status == "done" else event_type, f"{action} {status}: {name}", severity=severity, source="job", torrent_hash=str(h), torrent_name=name, action=action, details={"job_id": job_id, "status": status, "error": error, "result": result, "target_path": ctx.get("target_path"), "remove_data": ctx.get("remove_data")}, user_id=user_id)


def record_cache_diff(profile_id: int, added: list[dict], removed: list[str], updated: list[dict], old_rows: dict[str, dict]) -> None:
    for row in added or []:
        record(profile_id, "torrent_added", f"Torrent added: {row.get('name') or row.get('hash')}", source="poller", torrent_hash=row.get("hash"), torrent_name=row.get("name"), details={"size": row.get("size"), "path": row.get("path"), "label": row.get("label")})
    for h in removed or []:
        old = old_rows.get(str(h)) or {}
        record(profile_id, "torrent_removed", f"Torrent removed: {old.get('name') or h}", source="poller", torrent_hash=str(h), torrent_name=old.get("name"), details={"path": old.get("path"), "label": old.get("label")})
    for patch in updated or []:
        h = str(patch.get("hash") or "")
        old = old_rows.get(h) or {}
        was_complete = bool(old.get("complete")) or float(old.get("progress") or 0) >= 100
        is_complete = bool(patch.get("complete", old.get("complete"))) or float(patch.get("progress", old.get("progress") or 0) or 0) >= 100
        if h and not was_complete and is_complete:
            record(profile_id, "torrent_completed", f"Torrent completed: {old.get('name') or h}", source="poller", torrent_hash=h, torrent_name=old.get("name"), details={"ratio": patch.get("ratio", old.get("ratio")), "size": old.get("size"), "path": old.get("path")})


def list_logs(profile_id: int, *, limit: int = 200, offset: int = 0, event_type: str = "", q: str = "") -> dict:
    limit = max(1, min(int(limit or 200), 1000))
    offset = max(0, int(offset or 0))
    where = ["(profile_id=? OR profile_id IS NULL)"]
    params: list[Any] = [int(profile_id or 0)]
    if event_type:
        where.append("event_type=?")
        params.append(event_type)
    if q:
        where.append("(message LIKE ? OR torrent_name LIKE ? OR torrent_hash LIKE ? OR action LIKE ?)")
        like = f"%{q}%"
        params.extend([like, like, like, like])
    sql_where = " WHERE " + " AND ".join(where)
    with connect() as conn:
        rows = conn.execute(f"SELECT * FROM operation_logs{sql_where} ORDER BY id DESC LIMIT ? OFFSET ?", (*params, limit, offset)).fetchall()
        total = conn.execute(f"SELECT COUNT(*) AS n FROM operation_logs{sql_where}", tuple(params)).fetchone()["n"]
    return {"logs": [_row_to_public(r) for r in rows], "total": int(total or 0), "limit": limit, "offset": offset}


def stats(profile_id: int) -> dict:
    profile_id = int(profile_id or 0)
    with connect() as conn:
        total = conn.execute("SELECT COUNT(*) AS n FROM operation_logs WHERE profile_id=? OR profile_id IS NULL", (profile_id,)).fetchone()["n"]
        by_type = conn.execute("SELECT event_type, COUNT(*) AS n FROM operation_logs WHERE profile_id=? OR profile_id IS NULL GROUP BY event_type ORDER BY n DESC LIMIT 12", (profile_id,)).fetchall()
        by_day = conn.execute("SELECT substr(created_at,1,10) AS bucket, COUNT(*) AS n FROM operation_logs WHERE profile_id=? OR profile_id IS NULL GROUP BY bucket ORDER BY bucket DESC LIMIT 14", (profile_id,)).fetchall()
        by_month = conn.execute("SELECT substr(created_at,1,7) AS bucket, COUNT(*) AS n FROM operation_logs WHERE profile_id=? OR profile_id IS NULL GROUP BY bucket ORDER BY bucket DESC LIMIT 12", (profile_id,)).fetchall()
        top_actions = conn.execute("SELECT COALESCE(action, event_type) AS action, COUNT(*) AS n FROM operation_logs WHERE profile_id=? OR profile_id IS NULL GROUP BY COALESCE(action, event_type) ORDER BY n DESC LIMIT 12", (profile_id,)).fetchall()
    return {"total": int(total or 0), "by_type": by_type, "by_day": by_day, "by_month": by_month, "top_actions": top_actions, "settings": get_settings(profile_id)}


def clear(profile_id: int, *, event_type: str = "") -> int:
    where = ["(profile_id=? OR profile_id IS NULL)"]
    params: list[Any] = [int(profile_id or 0)]
    if event_type:
        where.append("event_type=?")
        params.append(event_type)
    with connect() as conn:
        cur = conn.execute("DELETE FROM operation_logs WHERE " + " AND ".join(where), tuple(params))
        return int(cur.rowcount or 0)


def apply_retention(profile_id: int, user_id: int | None = None) -> dict:
    settings = get_settings(profile_id, user_id)
    mode = settings.get("retention_mode") or "manual"
    deleted_days = 0
    deleted_lines = 0
    with connect() as conn:
        if mode in {"days", "both"}:
            cutoff = (datetime.now(timezone.utc) - timedelta(days=int(settings["retention_days"]))).isoformat(timespec="seconds")
            cur = conn.execute("DELETE FROM operation_logs WHERE (profile_id=? OR profile_id IS NULL) AND created_at<?", (int(profile_id or 0), cutoff))
            deleted_days = int(cur.rowcount or 0)
        if mode in {"lines", "both"}:
            keep = int(settings["retention_lines"])
            ids = conn.execute("SELECT id FROM operation_logs WHERE profile_id=? OR profile_id IS NULL ORDER BY id DESC LIMIT -1 OFFSET ?", (int(profile_id or 0), keep)).fetchall()
            if ids:
                placeholders = ",".join("?" for _ in ids)
                cur = conn.execute(f"DELETE FROM operation_logs WHERE id IN ({placeholders})", tuple(r["id"] for r in ids))
                deleted_lines = int(cur.rowcount or 0)
    return {"deleted_days": deleted_days, "deleted_lines": deleted_lines, "deleted": deleted_days + deleted_lines, "settings": settings}