/*
    DEDICATED JAVASCRIPT FOR AIMOJSTER.SI CHATBOT WIDGET
    Last Updated: 16. September 2025 (v8.0 - Final Production Version)
    Author: Gemini AI for AIMojster.si

    This is the final, clean production version of the chatbot script.
    It reliably creates, stores (per session), and sends a unique session ID with every user message,
    ensuring that the n8n workflow functions correctly.
*/

document.addEventListener('DOMContentLoaded', function() {

    // --- DOM ELEMENTI ---
    const chatWidgetButton = document.getElementById('chat-widget-button');
    const chatContainer = document.getElementById('chat-widget-container');
    const closeChatBtn = document.getElementById('close-chat-btn');
    const chatMessagesContainer = document.getElementById('chat-messages');
    const chatInputForm = document.getElementById('chat-input-form');
    const chatInputField = document.getElementById('chat-input');
    
    // --- KONFIGURACIJA ---
    const N8N_WEBHOOK_URL = 'https://n8n.spletnimojster.si/webhook/joze/chat';

    // Preverimo, ali obstajajo vsi potrebni HTML elementi za delovanje.
    if (!chatWidgetButton || !chatContainer || !chatInputForm) {
        console.error("Chatbot HTML elements could not be found. The script will not initialize.");
        return;
    }

    // ====================================================================== //
    // === UPRAVLJANJE S SEJO (SESSION ID MANAGEMENT) ===                     //
    // ====================================================================== //

    /**
     * Zanesljivo pridobi ali ustvari unikaten Session ID za trenutni pogovor.
     * Uporablja `sessionStorage`, kar pomeni, da ID obstane med osveževanjem strani,
     * a se ponastavi, ko uporabnik zapre zavihek brskalnika.
     * @returns {string} The unique session ID for the current chat session.
     */
    function getSessionId() {
        const SESSION_KEY = 'aimojster_chatbot_session_id'; // Uporabimo unikatno ime ključa
        let sessionId = sessionStorage.getItem(SESSION_KEY);

        if (!sessionId) {
            // crypto.randomUUID() je moderen, varen in standarden način za generiranje UUID-jev.
            sessionId = crypto.randomUUID();
            sessionStorage.setItem(SESSION_KEY, sessionId);
        }
        return sessionId;
    }

    // ====================================================================== //
    // === KOMUNIKACIJA Z N8N ===                                             //
    // ====================================================================== //

    /**
     * Sestavi in pošlje uporabnikovo sporočilo skupaj s session ID-jem na n8n webhook.
     * @param {string} userMessage - Sporočilo, ki ga je vnesel uporabnik.
     */
    async function sendMessageToBot(userMessage) {
        showTypingIndicator();

        // Pridobimo ali ustvarimo session ID za to sejo.
        const currentSessionId = getSessionId();

        // Sestavimo pravilen objekt (payload), ki ga n8n pričakuje.
        const payload = {
            sessionId: currentSessionId,
            chatInput: userMessage,
            action: "sendMessage"
        };
        
        try {
            const response = await fetch(N8N_WEBHOOK_URL, {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/json'
                },
                body: JSON.stringify(payload)
            });

            if (!response.ok) {
                throw new Error(`Server returned status: ${response.status}`);
            }

            const data = await response.json();
            const botReply = data.output;

            if (botReply) {
                addBotMessageToUI(botReply);
            } else {
                // To se zgodi, če n8n vrne prazen odgovor ali napačno strukturo.
                console.error("Response from bot was empty or in a malformed structure.", data);
                throw new Error("Malformed response from server.");
            }

        } catch (error) {
            console.error('Error communicating with the chatbot API:', error);
            addBotMessageToUI("Oprostite, prišlo je do tehnične napake. Poskusite znova kasneje.");
        }
    }

    // ====================================================================== //
    // === UPRAVLJANJE Z UI IN DOGODKI ===                                    //
    // ====================================================================== //
    
    // --- Pomožne UI funkcije ---
    function openChatWidget() {
        chatContainer.classList.remove('hidden');
        chatInputField.focus();
    }
    
    function closeChatWidget() {
        chatContainer.classList.add('hidden');
    }

    function addMessageToUI(text, sender) {
        const messageElement = document.createElement('div');
        messageElement.classList.add('chat-message', `${sender}-message`);
        messageElement.textContent = text;
        chatMessagesContainer.appendChild(messageElement);
        chatMessagesContainer.scrollTop = chatMessagesContainer.scrollHeight;
    }

    function showTypingIndicator() {
        if (chatMessagesContainer.querySelector('.typing-indicator')) return;
        const indicator = document.createElement('div');
        indicator.classList.add('chat-message', 'bot-message', 'typing-indicator');
        indicator.innerHTML = '<span>.</span><span>.</span><span>.</span>';
        chatMessagesContainer.appendChild(indicator);
        chatMessagesContainer.scrollTop = chatMessagesContainer.scrollHeight;
    }

    function hideTypingIndicator() {
        const indicator = chatMessagesContainer.querySelector('.typing-indicator');
        if (indicator) indicator.remove();
    }
    
    const addUserMessageToUI = (message) => addMessageToUI(message, 'user');
    const addBotMessageToUI = (message) => {
        hideTypingIndicator();
        addMessageToUI(message, 'bot');
    };

    // --- Glavni Event Listener za oddajo sporočila ---
    chatInputForm.addEventListener('submit', function(event) {
        event.preventDefault();
        const userMessage = chatInputField.value.trim();

        if (userMessage) {
            addUserMessageToUI(userMessage);
            sendMessageToBot(userMessage);
            chatInputField.value = '';
        }
    });

    // --- Event Listenerji za odpiranje in zapiranje okna ---
    chatWidgetButton.addEventListener('click', openChatWidget);
    closeChatBtn.addEventListener('click', closeChatWidget);

    console.log("Chatbot v8.0 (Final Production) initialized successfully.");
});