import { showAlert } from './shared_functions.js';

let chatCount = 0; // Zähler für Chat-Sessions
let currentChatId = null; // Aktuell angezeigte Chat-ID
let useMarkdown = true;

document.getElementById('newChatButton').addEventListener('click', () => {
    createNewChat();
});

document.getElementById('sendButton').addEventListener('click', () => {
    const chatBox = document.getElementById('chatBox');
    const chatInput = document.getElementById('chatInput');
    const messageText = chatInput.value.trim();

    if (messageText !== '' && currentChatId !== null) { // Stelle sicher, dass eine Chat-ID vorhanden ist
        const messageElement = document.createElement('div');
        messageElement.classList.add('chat-message', 'user');
        //messageElement.innerText = messageText;

        if (useMarkdown) {
            messageElement.innerHTML = renderMarkdown(messageText);
        } else {
            messageElement.innerText = messageText;
        }

        chatBox.prepend(messageElement);

        // Nachricht speichern
        saveMessage(currentChatId, messageText); // Verwende die aktuelle Chat-ID

        // Sidebar-Button für den Chat-Verlauf erstellen, falls noch nicht vorhanden
        if (document.getElementById(`chatSession-${currentChatId}`) === null) {
            createChatSessionButton(currentChatId);
        }

        chatInput.value = ''; // Input-Feld leeren
    }
});

function createNewChat() {
    // Erhöhe den Chat-Zähler und erstelle einen neuen Chat
    const newChatId = chatCount++;
    localStorage.setItem(`chatHistory-${newChatId}`, JSON.stringify([])); // Leeren Chat speichern
    createChatSessionButton(newChatId); // Button für den neuen Chat erstellen
    currentChatId = newChatId; // Setze die aktuelle Chat-ID
    loadChatHistory(currentChatId); // Lade den neuen Chat
}

async function saveMessage(chatId, message) {
    const chatHistory = JSON.parse(localStorage.getItem(`chatHistory-${chatId}`)) || [];
    chatHistory.push({ role: "user", content: message });
    localStorage.setItem(`chatHistory-${chatId}`, JSON.stringify(chatHistory));

    // Aktualisiere den Button-Text in der Sidebar
    updateChatSessionButton(chatId);

    // Sende die Nachricht an den Chatbot
    const userMessage = getLastUserMessage();
    if (userMessage) {
        let a = await stream_api_open_ai(userMessage);
        console.log("Komplette Nachricht: " + a)
        // Update progress bar:
        let consumption = await tokenize_api_open_ai()
        updateProgressBar(consumption.count, consumption.max_model_len);

        const chatHistory = JSON.parse(localStorage.getItem(`chatHistory-${chatId}`)) || [];
        chatHistory.push({ role: "assistant", content: a });
        localStorage.setItem(`chatHistory-${chatId}`, JSON.stringify(chatHistory));
    }
}

function updateChatSessionButton(chatId) {
    const button = document.getElementById(`chatSession-${chatId}`);
    if (button) {
        const chatHistory = JSON.parse(localStorage.getItem(`chatHistory-${chatId}`)) || [];
        // Hole die erste Nachricht oder lasse es leer, wenn keine vorhanden ist
        const chatName = chatHistory.length > 0 ? chatHistory[0].content.slice(0, 10) : ''; // Nimm die ersten 10 Zeichen der ersten Nachricht
        button.innerText = chatName + "..." || `Chat ${chatId + 1}`; // Falls leer, setze auf "Chat x"
    }
}

function createChatSessionButton(chatId) {
    const chatList = document.getElementById('chatList');

    // Container für Chat-Button und Löschen-Button
    const buttonContainer = document.createElement('div');
    buttonContainer.classList.add('chat-session-button-container');

    // Chat-Button
    const button = document.createElement('button');
    button.classList.add('chat-session-button');
    button.id = `chatSession-${chatId}`;
    button.innerText = `Chat ${chatId + 1}`; // Vorläufiger Name
    button.addEventListener('click', () => {
        loadChatHistory(chatId); // Lade den Chat-Verlauf und setze die aktuelle Chat-ID
        currentChatId = chatId; // Setze die aktuelle Chat-ID auf die ausgewählte Chat-ID
    });

    // Löschen-Button
    const deleteButton = document.createElement('button');
    deleteButton.classList.add('delete-chat-button');
    deleteButton.innerText = "✕";
    deleteButton.addEventListener('click', (event) => {
        event.stopPropagation(); // Verhindert, dass der Chat geladen wird, wenn auf Löschen geklickt wird
        deleteChat(chatId, buttonContainer);
        clearChat();
    });

    // Elemente hinzufügen
    buttonContainer.appendChild(button);
    buttonContainer.appendChild(deleteButton);
    chatList.appendChild(buttonContainer);
}

function clearChat(){
    const chatBox = document.getElementById('chatBox');
    chatBox.innerHTML = ''; // Aktuellen Chat leeren
}

function loadChatHistory(chatId) {
    const chatBox = document.getElementById('chatBox');
    chatBox.innerHTML = ''; // Aktuellen Chat leeren

    if (currentChatId === null) {
        return; // Wenn kein Chat ausgewählt ist, nichts laden
    }

    const chatHistory = JSON.parse(localStorage.getItem(`chatHistory-${chatId}`)) || [];
    chatHistory.forEach(entry => {
        const messageElement = document.createElement('div');
        messageElement.classList.add('chat-message', entry.role);
        messageElement.innerHTML = renderMarkdown(entry.content);
        chatBox.prepend(messageElement);
    });
}

function deleteChat(chatId, buttonContainer) {
    // Entferne den Chat-Verlauf aus dem LocalStorage
    localStorage.removeItem(`chatHistory-${chatId}`);
    // Entferne den Button aus der Sidebar
    buttonContainer.remove();
}

// Lade alle Chat-Sitzungen beim Start
function loadAllChatSessions() {
    Object.keys(localStorage).forEach((key) => {
        if (key.startsWith('chatHistory-')) {
            const chatId = parseInt(key.split('-')[1], 10);
            createChatSessionButton(chatId);
            chatCount = Math.max(chatCount, chatId + 1); // Chat-Zähler aktualisieren
        }
    });

    for (let i = 0; i < chatCount; i++) {// Aktualisiere die Namen an der Seite
        updateChatSessionButton(i);
    }
    // Lade den neuesten Chat-Verlauf
    if (chatCount > 0) {
        loadChatHistory(chatCount - 1);
        currentChatId = chatCount - 1; // Setze die aktuelle Chat-ID
    } else {
        const chatBox = document.getElementById('chatBox');
        chatBox.innerHTML = ''; // Chat-Box leer, wenn keine Chats existieren
    }
}

// Beim Laden der Seite alle Chat-Sitzungen laden
window.addEventListener('DOMContentLoaded', loadAllChatSessions);

const chatInput = document.getElementById('chatInput');

// Event-Listener für das Senden der Nachricht und das Erstellen eines Zeilenumbruchs
chatInput.addEventListener('keydown', (event) => {
    if (event.key === 'Enter') {
        if (currentChatId == null){
            createNewChat();
        }

        // Prüfen, ob die Shift-Taste nicht gedrückt wird
        if (!event.shiftKey) {
            event.preventDefault(); // Verhindert das Standardverhalten (Absenden des Formulars)
            const messageText = chatInput.value.trim();
            if (messageText !== '' && currentChatId !== null) {
                const messageElement = document.createElement('div');
                messageElement.classList.add('chat-message', 'user');
                messageElement.innerText = messageText;
                document.getElementById('chatBox').prepend(messageElement);

                // Nachricht speichern
                saveMessage(currentChatId, messageText);

                // Sidebar-Button für den Chat-Verlauf erstellen, falls noch nicht vorhanden
                if (document.getElementById(`chatSession-${currentChatId}`) === null) {
                    createChatSessionButton(currentChatId);
                }

                chatInput.value = ''; // Input-Feld leeren
            }
        } else {
            // Shift + Enter: Zeilenumbruch
            chatInput.value += '\n'; // Zeilenumbruch in das Textfeld einfügen
        }
    }
});

/* OpenAI zeug */

async function getModels() {

    try {
        const response = await fetch(`http://localhost:8015/v1/models`, {
            method: 'GET',
            headers: {
                'Authorization': `Bearer YOUR_API_KEY`,
                'Content-Type': 'application/json',
            }
        });

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

        const models = await response.json();
        return models.data[0].id

    } catch (error) {
        if (error.message.includes('502')) {
            showAlert("Server Error: 502 \nMaybe the LLM is offline?")
            console.error('Bad Gateway: The server is acting as a gateway or proxy and received an invalid response from the upstream server.');
        } else {
            // Handle other errors here
            console.error('Error fetching models:', error);
        }
    }
}

function getAllCurrentChatMessages() {
    const cookieData = JSON.parse(localStorage.getItem(`chatHistory-${currentChatId}`)) || [];
    return cookieData
}


function getLastUserMessage() {
    // Lade die Cookie-Daten (ersetze dies durch den tatsächlichen Weg zur Cookie-Datenstruktur)
    const cookieData = JSON.parse(localStorage.getItem(`chatHistory-${currentChatId}`)) || [];


    // Filter nur die User-Nachrichten heraus
    const userMessages = cookieData.filter(message => message.role === "user");

    // Falls es User-Nachrichten gibt, die letzte davon zurückgeben
    if (userMessages.length > 0) {
        return userMessages[userMessages.length - 1].content;
    }

    return ''; // Rückgabe eines leeren Strings, falls keine Nachricht gefunden wird
}

function renderMarkdown(content) {
    return  marked.parse(content);
}

async function stream_api_open_ai(userMessage) {
    // Neues div-Element für die Antwort des Chatbots erstellen
    const chatBox = document.getElementById('chatBox');
    const botMessageDiv = document.createElement('div');
    botMessageDiv.className = 'chat-message assistant';
    chatBox.prepend(botMessageDiv);

    let send_message_system = [{ role: "system", content: "You are a knowledgeable assistant." }];
    let send_message_user = getAllCurrentChatMessages();
    let send_message_final = send_message_system.concat(send_message_user)
    console.log(send_message_final)

    const response = await fetch('http://localhost:8015/v1/chat/completions', {
        method: 'POST',
        headers: {
            'Content-Type': 'application/json',
            'Authorization': `Bearer YOUR_API_KEY`,
        },
        body: JSON.stringify({
            model: await getModels(),
            messages: send_message_final,
            stream: true,
            temperature: 0.3
        })
    });

    const reader = response.body.getReader();
    const decoder = new TextDecoder('utf-8');

    let result = '';
    while (true) {
        const { done, value } = await reader.read();
        if (done) break;

        const chunk = decoder.decode(value, { stream: true });
        const lines = chunk.split('\n');

        for (const line of lines) {
            if (line && line.includes('data: ')) {
                const jsonStr = line.replace('data: ', '').trim();

                if (jsonStr === '[DONE]'){
                    break;
                }

                try {
                    const json = JSON.parse(jsonStr);
                    if (json.choices[0].delta.content) {
                        const token = json.choices[0].delta.content;
                        result += token;

                        if (useMarkdown) {
                            botMessageDiv.innerHTML = renderMarkdown(result);
                        } else {
                            botMessageDiv.textContent = result;
                        }
                    }
                } catch (error) {
                    console.error('Error parsing JSON:', error, 'Received:', jsonStr);
                }
            }
        }
    }
    return result;
}

function formatArrayToCustomString(array) {
    return '[' +
        array.map(dict => {
            return '{' +
                Object.entries(dict)
                    .map(([key, value]) => `'${key}':'${value}'`)
                    .join(', ') +
                '}';
        }).join(', ') +
        ']';
}

// Tokenizer
async function tokenize_api_open_ai() {

    let send_message_system = [{ role: "system", content: "You are a knowledgeable assistant." }];
    let send_message_user = getAllCurrentChatMessages();
    let send_message_final = send_message_system.concat(send_message_user)
    let formattedString = `"${formatArrayToCustomString(send_message_final)}"`;
    console.log(formattedString)

    const response = await fetch('http://localhost:8015/tokenize', {
        method: 'POST',
        headers: {
            'Content-Type': 'application/json',
            'Authorization': `Bearer YOUR_API_KEY`,
        },
        body: JSON.stringify({
            model: await getModels(),
            prompt: formattedString,
            add_special_tokens: true
        })
    });
    // Check if the response is successful
    if (!response.ok) {
        throw new Error(`HTTP error! status: ${response.status}`);
    }

    const json = await response.json(); // Await the response.json() promise

    console.log(json); // Log the parsed JSON response
    return json

}

// Progress Bar

// Function to update the progress bar
function updateProgressBar(currentUsage, maxUsage) {
    const percentage = (currentUsage / maxUsage) * 100;

    // Update the width of the progress bar
    const progressBar = document.getElementById('progress-bar');
    progressBar.style.width = `${percentage}%`;

    // Update the text
    const usageText = document.getElementById('usage-text');
    usageText.innerText = `${currentUsage} / ${maxUsage} used`;
}