Flowlitics Backend Engine & API

---
config:
  flowchart:
    htmlLabels: false
---
graph TD
    subgraph "Initiators"
        direction LR
        User["`User / Frontend UI`"]
        Scheduler["`Cron Scheduler
        (node-cron)`"]
    end

    subgraph "Sistema Flowlitics Backend"
        direction TB
        
        subgraph "API Layer (Express.js)"
            API_Gateway["`API REST
            (Server Express)`"]
            Validation["`Input Validation
            (Joi)`"]
        end

        subgraph "Core Logic & Services"
            FlowService["`Flow Service
            (Gestione Flow)`"]
            ExecutionService["`Execution Engine
            (Esegue i nodi in-process)`"]
            PluginSystem["`Node Executor
            (Carica e usa SDK esterni)`"]
        end

        API_Gateway -- "HTTP Requests" --> Validation
        Validation -- "Valid Data" --> FlowService
        Validation -- "Valid Data" --> ExecutionService
        
        ExecutionService -- "Esegue" --> PluginSystem
    end

    subgraph "Data & Logging"
        direction TB
        MongoDB["`MongoDB
        (Flows, Executions, Logs)
        Gestito da Mongoose`"]
        Logger["`Logger
        (Winston)`"]
    end
    
    subgraph "Servizi Esterni (via SDKs)"
        direction TB
        LLMs["`LLMs
        (OpenAI, Groq, Anthropic, etc.)`"]
        Tools["`Tools
        (Tavily, Axios)`"]
    end

    %% --- Connessioni ---
    User -- "API Calls" --> API_Gateway
    Scheduler -- "Triggers" --> ExecutionService
    
    FlowService -- "CRUD Operations" --> MongoDB
    ExecutionService -- "CRUD Operations" --> MongoDB
    ExecutionService -- "Logs to" --> Logger
    PluginSystem -- "Logs to" --> Logger
    
    PluginSystem -- "Calls" --> LLMs
    PluginSystem -- "Calls" --> Tools