"""
User store — PostgreSQL-backed.
Keyed by Azure AD oid (object ID).
"""

import logging
from datetime import datetime, timezone
from typing import Dict, Optional

from ..config_runtime import server_config
from ..db.pool import get_pool

logger = logging.getLogger(__name__)


def _row_to_dict(row) -> Dict:
    return {
        'id': row['id'],
        'email': row['email'],
        'name': row['name'],
        'role': row['role'],
        'active': row['active'],
        'created': row['created_at'].isoformat() if row['created_at'] else None,
        'last_seen': row['last_seen_at'].isoformat() if row['last_seen_at'] else None,
    }


async def get_user(user_id: str) -> Optional[Dict]:
    pool = get_pool()
    async with pool.acquire() as conn:
        row = await conn.fetchrow('SELECT * FROM users WHERE id = $1', user_id)
        return _row_to_dict(row) if row else None


async def upsert_user(user_id: str, email: str, name: str, role: Optional[str] = None) -> Dict:
    """
    Create or update user. On first creation, grants admin if email is in ADMIN_EMAILS.
    """
    pool = get_pool()
    async with pool.acquire() as conn:
        existing = await conn.fetchrow('SELECT * FROM users WHERE id = $1', user_id)

        if existing is None:
            default_role = 'admin' if email and email.lower() in server_config.ADMIN_EMAILS else 'user'
            row = await conn.fetchrow('''
                INSERT INTO users (id, email, name, role, active)
                VALUES ($1, $2, $3, $4, TRUE)
                RETURNING *
            ''', user_id, email or '', name or '', role or default_role)
        else:
            new_role = role if role is not None else existing['role']
            row = await conn.fetchrow('''
                UPDATE users
                SET email = $2, name = $3, role = $4, last_seen_at = NOW()
                WHERE id = $1
                RETURNING *
            ''', user_id, email or existing['email'], name or existing['name'], new_role)

        return _row_to_dict(row)


async def list_users() -> list:
    pool = get_pool()
    async with pool.acquire() as conn:
        rows = await conn.fetch('SELECT * FROM users ORDER BY last_seen_at DESC')
        return [_row_to_dict(r) for r in rows]


async def set_role(user_id: str, role: str) -> Optional[Dict]:
    if role not in ('user', 'admin'):
        return None
    pool = get_pool()
    async with pool.acquire() as conn:
        row = await conn.fetchrow(
            'UPDATE users SET role = $2 WHERE id = $1 RETURNING *', user_id, role
        )
        return _row_to_dict(row) if row else None


async def set_active(user_id: str, active: bool) -> Optional[Dict]:
    pool = get_pool()
    async with pool.acquire() as conn:
        row = await conn.fetchrow(
            'UPDATE users SET active = $2 WHERE id = $1 RETURNING *', user_id, active
        )
        return _row_to_dict(row) if row else None