import os
import json
from datetime import datetime
from utils import load_config, load_json, save_json

def get_next_id(data_list, id_prefix, id_field):
    """Generates the next incremental ID for clients or projects."""
    if not data_list:
        return f"{id_prefix}-001"
    ids = [int(item[id_field].split('-')[1]) for item in data_list]
    return f"{id_prefix}-{max(ids) + 1:03d}"

def select_or_create_client(data_dir, clients_data):
    """Allows selecting an active client or creating a new one."""
    active_clients = [c for c in clients_data["Clients"] if c.get("Active", True)]
    
    print("\n--- Select Client ---")
    for i, client in enumerate(active_clients, 1):
        print(f"{i}. {client['Name']}")
    print(f"{len(active_clients) + 1}. [ADD NEW CLIENT]")
    
    choice = input("\nSelect a number: ")
    if choice == str(len(active_clients) + 1):
        # Create New Client Flow[cite: 2]
        new_name = input("Client Name: ")
        new_rate = float(input("Default Hourly Rate: ") or 0)
        new_id = get_next_id(clients_data["Clients"], "CLT", "ClientID")
        
        new_client = {
            "ClientID": new_id,
            "Name": new_name,
            "Active": True,
            "BillingAddress": {"Street1": "", "Street2": "", "City": "", "State": "", "PostalCode": "", "Country": ""},
            "BillingEmail": "",
            "DefaultRate": new_rate
        }
        clients_data["Clients"].append(new_client)
        save_json(os.path.join(data_dir, "Clients.json"), clients_data)
        return new_id
    else:
        return active_clients[int(choice) - 1]["ClientID"]

def select_or_create_project(data_dir, projects_data, client_id):
    """Allows selecting an active project for the client or creating a new one."""
    client_projects = [p for p in projects_data["Projects"] if p["ClientID"] == client_id and p.get("Active", True)]
    
    print("\n--- Select Project ---")
    print("0. No Project")
    for i, project in enumerate(client_projects, 1):
        print(f"{i}. {project['Name']}")
    print(f"{len(client_projects) + 1}. [ADD NEW PROJECT]")
    
    choice = input("\nSelect a number: ")
    if choice == "0":
        return ""
    elif choice == str(len(client_projects) + 1):
        # Create New Project Flow[cite: 2]
        new_name = input("Project Name: ")
        new_rate = float(input("Project Billing Rate (0 for client default): ") or 0)
        new_id = get_next_id(projects_data["Projects"], "PRJ", "ProjectID")
        
        new_project = {
            "ProjectID": new_id,
            "ClientID": client_id,
            "Name": new_name,
            "BillingRate": new_rate,
            "Active": True
        }
        projects_data["Projects"].append(new_project)
        save_json(os.path.join(data_dir, "Projects.json"), projects_data)
        return new_id
    else:
        return client_projects[int(choice) - 1]["ProjectID"]

def main():
    config = load_config()
    data_dir = config["DataDirectory"]
    
    # Load existing data[cite: 2]
    clients_data = load_json(os.path.join(data_dir, "Clients.json"), {"Clients": []})
    projects_data = load_json(os.path.join(data_dir, "Projects.json"), {"Projects": []})

    # Collect Entry Details[cite: 2]
    date_str = input(f"Date (YYYY-MM-DD) [Default: {datetime.now().strftime('%Y-%m-%d')}]: ") or datetime.now().strftime("%Y-%m-%d")
    duration = float(input("Duration (e.g., 1.5): "))
    
    client_id = select_or_create_client(data_dir, clients_data)
    project_id = select_or_create_project(data_dir, projects_data, client_id)
    
    description = input("Description: ")

    # Generate Entry[cite: 2]
    entry_id = datetime.now().strftime("%Y%m%d%H%M%S")
    entry = {
        "ID": entry_id,
        "Date": date_str,
        "Duration": duration,
        "ClientID": client_id,
        "ProjectID": project_id,
        "Description": description,
        "Invoiced": False,
        "InvoiceNumber": ""
    }

    # Save to Annual Log[cite: 2]
    year = date_str.split('-')[0]
    log_path = os.path.join(data_dir, f"{year}_Time_Log.json")
    log_data = load_json(log_path, {"Year": int(year), "Entries": []})
    log_data["Entries"].append(entry)
    save_json(log_path, log_data)

    print(f"\nSuccess: Entry {entry_id} saved to {year}_Time_Log.json")

if __name__ == "__main__":
    main()