import os
import json
from instagrapi import Client

INSTAGRAM_ACCOUNTS = json.loads(os.getenv("INSTAGRAM_ACCOUNTS", "[]"))
SESSION_DIR = os.path.join(os.getcwd(), "instagram_sessions")
os.makedirs(SESSION_DIR, exist_ok=True)

# Global cache of logged-in clients
client_cache: dict[str, Client] = {}


def get_logged_in_client() -> Client:
    global client_cache

    for account in INSTAGRAM_ACCOUNTS:
        username = account["username"]
        password = account["password"]

        # ✅ Return from memory if already logged in
        if username in client_cache:
            return client_cache[username]

        session_path = os.path.join(SESSION_DIR, f"{username}.json")
        client = Client()

        try:
            if os.path.exists(session_path):
                with open(session_path, "r") as f:
                    session_data = json.load(f)
                if isinstance(session_data, dict):
                    client.load_settings(session_data)
                else:
                    raise ValueError("Invalid session format")

            client.login(username, password)

            # Save session if freshly logged in
            if not os.path.exists(session_path):
                with open(session_path, "w") as f:
                    json.dump(client.get_settings(), f)

            print(f"✅ Logged in and cached: {username}")
            client_cache[username] = client
            return client

        except Exception as e:
            print(f"❌ Login failed for {username}: {e}")
            if os.path.exists(session_path):
                os.remove(session_path)
                print(f"🧹 Removed invalid session for {username}")

    raise Exception("❌ All Instagram accounts failed login.")