# db_users.py
import sqlite3
from contextlib import contextmanager
from typing import Optional
import bcrypt

DB_PATH = "app.db"

@contextmanager
def get_conn():
    conn = sqlite3.connect(DB_PATH, check_same_thread=False)
    conn.row_factory = sqlite3.Row
    try:
        yield conn
        conn.commit()
    finally:
        conn.close()

def init_db():
    with get_conn() as conn:
        conn.execute("""
        CREATE TABLE IF NOT EXISTS users (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            username TEXT NOT NULL UNIQUE,
            display_name TEXT,
            email TEXT,
            password_hash BLOB NOT NULL,
            role TEXT NOT NULL DEFAULT 'user',
            is_active INTEGER NOT NULL DEFAULT 1,
            created_at TEXT NOT NULL DEFAULT (datetime('now'))
        )
        """)

def list_users():
    with get_conn() as conn:
        rows = conn.execute("""
            SELECT id, username, display_name, email, role, is_active, created_at
            FROM users ORDER BY id
        """).fetchall()
        return [dict(r) for r in rows]

def get_user(user_id: int) -> Optional[dict]:
    with get_conn() as conn:
        r = conn.execute("""
            SELECT id, username, display_name, email, role, is_active
            FROM users WHERE id = ?
        """, (user_id,)).fetchone()
        return dict(r) if r else None

def create_user(username: str, password: str, display_name: str = "", email: str = "", role: str = "user", is_active: bool = True):
    pw_hash = bcrypt.hashpw(password.encode("utf-8"), bcrypt.gensalt())
    with get_conn() as conn:
        conn.execute("""
            INSERT INTO users (username, display_name, email, password_hash, role, is_active)
            VALUES (?, ?, ?, ?, ?, ?)
        """, (username, display_name, email, pw_hash, role, 1 if is_active else 0))

def update_user(user_id: int, display_name: str, email: str, role: str, is_active: bool):
    with get_conn() as conn:
        conn.execute("""
            UPDATE users
            SET display_name=?, email=?, role=?, is_active=?
            WHERE id=?
        """, (display_name, email, role, 1 if is_active else 0, user_id))

def set_password(user_id: int, new_password: str):
    pw_hash = bcrypt.hashpw(new_password.encode("utf-8"), bcrypt.gensalt())
    with get_conn() as conn:
        conn.execute("UPDATE users SET password_hash=? WHERE id=?", (pw_hash, user_id))

def delete_user(user_id: int):
    with get_conn() as conn:
        conn.execute("DELETE FROM users WHERE id=?", (user_id,))