from __future__ import annotations

from dataclasses import dataclass
from datetime import datetime, timezone

import aiosqlite


@dataclass
class LinkedUser:
    telegram_id: int
    api_token: str
    ha_user_id: int
    display_name: str
    username: str
    session_id: int
    reminder_seq: int
    pomodoro_seq: int


class Storage:
    def __init__(self, db_path: str) -> None:
        self.db_path = db_path
        self._db: aiosqlite.Connection | None = None

    async def connect(self) -> None:
        self._db = await aiosqlite.connect(self.db_path)
        self._db.row_factory = aiosqlite.Row
        await self._db.executescript(
            """
            CREATE TABLE IF NOT EXISTS users (
                telegram_id INTEGER PRIMARY KEY,
                api_token TEXT NOT NULL,
                ha_user_id INTEGER NOT NULL,
                display_name TEXT NOT NULL DEFAULT '',
                username TEXT NOT NULL DEFAULT '',
                session_id INTEGER NOT NULL,
                reminder_seq INTEGER NOT NULL DEFAULT 0,
                pomodoro_seq INTEGER NOT NULL DEFAULT 0,
                created_at TEXT NOT NULL
            );

            CREATE TABLE IF NOT EXISTS session_cursors (
                telegram_id INTEGER NOT NULL,
                session_id INTEGER NOT NULL,
                last_message_id INTEGER NOT NULL DEFAULT 0,
                PRIMARY KEY (telegram_id, session_id)
            );
            """
        )
        await self._db.commit()

    async def close(self) -> None:
        if self._db:
            await self._db.close()
            self._db = None

    @property
    def db(self) -> aiosqlite.Connection:
        if not self._db:
            raise RuntimeError("Storage is not connected")
        return self._db

    async def get_user(self, telegram_id: int) -> LinkedUser | None:
        cursor = await self.db.execute(
            """
            SELECT telegram_id, api_token, ha_user_id, display_name, username,
                   session_id, reminder_seq, pomodoro_seq
            FROM users WHERE telegram_id = ?
            """,
            (telegram_id,),
        )
        row = await cursor.fetchone()
        if not row:
            return None
        return LinkedUser(
            telegram_id=int(row["telegram_id"]),
            api_token=str(row["api_token"]),
            ha_user_id=int(row["ha_user_id"]),
            display_name=str(row["display_name"] or ""),
            username=str(row["username"] or ""),
            session_id=int(row["session_id"]),
            reminder_seq=int(row["reminder_seq"]),
            pomodoro_seq=int(row["pomodoro_seq"]),
        )

    async def list_linked_users(self) -> list[LinkedUser]:
        cursor = await self.db.execute(
            """
            SELECT telegram_id, api_token, ha_user_id, display_name, username,
                   session_id, reminder_seq, pomodoro_seq
            FROM users
            """
        )
        rows = await cursor.fetchall()
        return [
            LinkedUser(
                telegram_id=int(row["telegram_id"]),
                api_token=str(row["api_token"]),
                ha_user_id=int(row["ha_user_id"]),
                display_name=str(row["display_name"] or ""),
                username=str(row["username"] or ""),
                session_id=int(row["session_id"]),
                reminder_seq=int(row["reminder_seq"]),
                pomodoro_seq=int(row["pomodoro_seq"]),
            )
            for row in rows
        ]

    async def link_user(
        self,
        *,
        telegram_id: int,
        api_token: str,
        ha_user_id: int,
        display_name: str,
        username: str,
        session_id: int,
    ) -> None:
        now = datetime.now(timezone.utc).isoformat()
        await self.db.execute(
            """
            INSERT INTO users (
                telegram_id, api_token, ha_user_id, display_name, username,
                session_id, reminder_seq, pomodoro_seq, created_at
            ) VALUES (?, ?, ?, ?, ?, ?, 0, 0, ?)
            ON CONFLICT(telegram_id) DO UPDATE SET
                api_token = excluded.api_token,
                ha_user_id = excluded.ha_user_id,
                display_name = excluded.display_name,
                username = excluded.username,
                session_id = excluded.session_id,
                reminder_seq = 0,
                pomodoro_seq = 0
            """,
            (telegram_id, api_token, ha_user_id, display_name, username, session_id, now),
        )
        await self.db.commit()

    async def unlink_user(self, telegram_id: int) -> bool:
        cursor = await self.db.execute("DELETE FROM users WHERE telegram_id = ?", (telegram_id,))
        await self.db.execute(
            "DELETE FROM session_cursors WHERE telegram_id = ?",
            (telegram_id,),
        )
        await self.db.commit()
        return cursor.rowcount > 0

    async def set_session_id(self, telegram_id: int, session_id: int) -> None:
        await self.db.execute(
            "UPDATE users SET session_id = ? WHERE telegram_id = ?",
            (session_id, telegram_id),
        )
        await self.db.commit()

    async def update_seq(
        self,
        telegram_id: int,
        *,
        reminder_seq: int | None = None,
        pomodoro_seq: int | None = None,
    ) -> None:
        if reminder_seq is not None:
            await self.db.execute(
                "UPDATE users SET reminder_seq = ? WHERE telegram_id = ?",
                (reminder_seq, telegram_id),
            )
        if pomodoro_seq is not None:
            await self.db.execute(
                "UPDATE users SET pomodoro_seq = ? WHERE telegram_id = ?",
                (pomodoro_seq, telegram_id),
            )
        await self.db.commit()

    async def get_last_message_id(self, telegram_id: int, session_id: int) -> int:
        cursor = await self.db.execute(
            """
            SELECT last_message_id FROM session_cursors
            WHERE telegram_id = ? AND session_id = ?
            """,
            (telegram_id, session_id),
        )
        row = await cursor.fetchone()
        return int(row["last_message_id"]) if row else 0

    async def set_last_message_id(self, telegram_id: int, session_id: int, message_id: int) -> None:
        await self.db.execute(
            """
            INSERT INTO session_cursors (telegram_id, session_id, last_message_id)
            VALUES (?, ?, ?)
            ON CONFLICT(telegram_id, session_id) DO UPDATE SET
                last_message_id = excluded.last_message_id
            """,
            (telegram_id, session_id, message_id),
        )
        await self.db.commit()