let conversation = [
    { role: 'bot', message: 'Hello! I’m Chef Bot, your culinary assistant! What’s your name?' }
];
let selectedItems = [];
let selectionBoxVisible = false;
const searchCache = new Map();
const MAX_RETRIES = 3;

function addMessage(role, message, isDebug = false) {
    const chatMessages = document.getElementById('chatMessages');
    if (!chatMessages) {
        console.error('Chat messages container not found!');
        return;
    }
    const messageDiv = document.createElement('div');
    messageDiv.className = role === 'bot' ? 'bot-message' : 'user-message';
    messageDiv.textContent = message;
    chatMessages.appendChild(messageDiv);
    chatMessages.scrollTop = chatMessages.scrollHeight;
    if (isDebug) console.log(`[${role.toUpperCase()}] ${message}`);
}

function showToast(message) {
    const toast = document.createElement('div');
    toast.className = 'toast';
    toast.textContent = message;
    document.body.appendChild(toast);
    setTimeout(() => toast.remove(), 3000);
}

function sendMessage() {
    const userInput = document.getElementById('userInput');
    if (!userInput) {
        console.error('User input field not found!');
        return;
    }
    const message = userInput.value.trim();
    if (message) {
        addMessage('user', message, true);
        conversation.push({ role: 'user', message: message });
        selectionBoxVisible = true;
        handleResponse(message);
        showToast(`Sent: "${message}"`);
    } else {
        addMessage('bot', 'Please type a dish or preference! 😄');
        showToast('Input is empty!');
    }
    userInput.value = '';
    updateSelectionBox();
}

function handleResponse(userInput) {
    const lowerInput = userInput.toLowerCase();
    let botResponse = '';

    if (conversation.length === 2) {
        botResponse = `Hi ${userInput}! 🍳 Search for a dish or choose a preference below!`;
        displayOptions([
            { text: 'Vegetarian', class: 'green' },
            { text: 'Non-Vegetarian', class: 'red' },
            { text: 'Both', class: 'gray' }
        ]);
        addMessage('bot', botResponse);
    } else if (lowerInput === 'vegetarian' || lowerInput === 'non-vegetarian' || lowerInput === 'both') {
        botResponse = `Fetching ${lowerInput} dishes...`;
        addMessage('bot', botResponse);
        fetchMenuItems(lowerInput);
    } else {
        botResponse = `Looking for "${userInput}"...`;
        addMessage('bot', botResponse);
        fetchMenuItems(null, userInput);
    }
}

function debounce(func, wait) {
    let timeout;
    return function (...args) {
        clearTimeout(timeout);
        timeout = setTimeout(() => func.apply(this, args), wait);
    };
}

function updateSelectionBox() {
    const chatMessages = document.getElementById('chatMessages');
    if (!chatMessages) return;

    const existingBox = document.querySelector('.selection-box');
    if (existingBox) existingBox.remove();

    if (!selectionBoxVisible && selectedItems.length === 0) return;

    const selectionBox = document.createElement('div');
    selectionBox.className = 'selection-box';

    const clearAllButton = document.createElement('button');
    clearAllButton.textContent = 'Clear All';
    clearAllButton.className = 'remove-button';
    clearAllButton.setAttribute('aria-label', 'Clear all selected items');
    clearAllButton.tabIndex = 0;
    clearAllButton.onclick = () => {
        selectedItems = [];
        addMessage('bot', 'Cleared all items.');
        showToast('All items cleared!');
        updateSelectionBox();
    };
    selectionBox.appendChild(clearAllButton);

    const vegButton = document.createElement('button');
    vegButton.textContent = 'Veg';
    vegButton.className = 'option-button green';
    vegButton.setAttribute('aria-label', 'Select vegetarian dishes');
    vegButton.tabIndex = 0;
    vegButton.onclick = () => {
        addMessage('user', 'Vegetarian', true);
        conversation.push({ role: 'user', message: 'Vegetarian' });
        handleResponse('vegetarian');
        showToast('Selected Vegetarian');
    };
    selectionBox.appendChild(vegButton);

    const nonVegButton = document.createElement('button');
    nonVegButton.textContent = 'Non-Veg';
    nonVegButton.className = 'option-button red';
    nonVegButton.setAttribute('aria-label', 'Select non-vegetarian dishes');
    nonVegButton.tabIndex = 0;
    nonVegButton.onclick = () => {
        addMessage('user', 'Non-Vegetarian', true);
        conversation.push({ role: 'user', message: 'Non-Vegetarian' });
        handleResponse('non-vegetarian');
        showToast('Selected Non-Vegetarian');
    };
    selectionBox.appendChild(nonVegButton);

    const bothButton = document.createElement('button');
    bothButton.textContent = 'Both';
    bothButton.className = 'option-button gray';
    bothButton.setAttribute('aria-label', 'Select both vegetarian and non-vegetarian dishes');
    bothButton.tabIndex = 0;
    bothButton.onclick = () => {
        addMessage('user', 'Both', true);
        conversation.push({ role: 'user', message: 'Both' });
        handleResponse('both');
        showToast('Selected Both');
    };
    selectionBox.appendChild(bothButton);

    const label = document.createElement('span');
    label.textContent = 'Selected:';
    selectionBox.appendChild(label);

    selectedItems.forEach((item, index) => {
        const itemContainer = document.createElement('div');
        itemContainer.className = 'selected-item';
        itemContainer.dataset.hidden = item.source === 'Sector_Detail__c' ? 'true' : 'false';

        const img = document.createElement('img');
        img.src = item.image_url || 'https://via.placeholder.com/30?text=Item';
        img.alt = item.name;
        img.className = 'selected-item-image';
        itemContainer.appendChild(img);

        const contentDiv = document.createElement('div');
        contentDiv.className = 'selected-item-content';

        const itemSpan = document.createElement('span');
        itemSpan.textContent = `${item.name} (Qty: ${item.quantity || 1})`;
        contentDiv.appendChild(itemSpan);

        const quantityDiv = document.createElement('div');
        quantityDiv.className = 'quantity-controls';
        const decButton = document.createElement('button');
        decButton.textContent = '-';
        decButton.className = 'quantity-button';
        decButton.setAttribute('aria-label', `Decrease quantity of ${item.name}`);
        decButton.tabIndex = 0;
        decButton.onclick = () => {
            if (item.quantity > 1) {
                item.quantity -= 1;
                updateSelectionBox();
                showToast(`Decreased quantity of ${item.name}`);
            }
        };
        quantityDiv.appendChild(decButton);

        const incButton = document.createElement('button');
        incButton.textContent = '+';
        incButton.className = 'quantity-button';
        incButton.setAttribute('aria-label', `Increase quantity of ${item.name}`);
        incButton.tabIndex = 0;
        incButton.onclick = () => {
            item.quantity += 1;
            updateSelectionBox();
            showToast(`Increased quantity of ${item.name}`);
        };
        quantityDiv.appendChild(incButton);
        contentDiv.appendChild(quantityDiv);

        if (item.source === 'Sector_Detail__c') {
            const showButton = document.createElement('button');
            showButton.textContent = 'Show';
            showButton.className = 'show-button';
            showButton.setAttribute('aria-label', `Show details for ${item.name}`);
            showButton.tabIndex = 0;
            showButton.onclick = () => toggleDescription(itemContainer, item.description, item.name);
            contentDiv.appendChild(showButton);
        }

        itemContainer.appendChild(contentDiv);

        const removeButton = document.createElement('button');
        removeButton.textContent = 'X';
        removeButton.className = 'remove-button';
        removeButton.setAttribute('aria-label', `Remove ${item.name} from selection`);
        removeButton.tabIndex = 0;
        removeButton.onclick = () => {
            selectedItems.splice(index, 1);
            addMessage('bot', `Removed "${item.name}".`);
            showToast(`Removed "${item.name}"`);
            updateSelectionBox();
        };
        itemContainer.appendChild(removeButton);

        selectionBox.appendChild(itemContainer);
    });

    const textInput = document.createElement('input');
    textInput.type = 'text';
    textInput.placeholder = 'Add item...';
    textInput.className = 'manual-input';
    textInput.setAttribute('aria-label', 'Add item manually');
    textInput.tabIndex = 0;
    const debouncedFetch = debounce((e) => {
        if (e.key === 'Enter' && textInput.value.trim()) {
            const itemName = textInput.value.trim();
            fetchSectorItemDetails(itemName);
            textInput.value = '';
            showToast(`Searching for "${itemName}"...`);
        }
    }, 300);
    textInput.addEventListener('keypress', debouncedFetch);
    selectionBox.appendChild(textInput);

    if (selectedItems.length > 0) {
        const quantityInput = document.createElement('input');
        quantityInput.type = 'number';
        quantityInput.min = '1';
        quantityInput.value = '1';
        quantityInput.placeholder = 'Qty';
        quantityInput.className = 'quantity-input';
        quantityInput.setAttribute('aria-label', 'Set default quantity for all items');
        quantityInput.tabIndex = 0;
        selectionBox.appendChild(quantityInput);

        const submitButton = document.createElement('button');
        submitButton.textContent = 'Submit';
        submitButton.className = 'submit-button';
        submitButton.setAttribute('aria-label', 'Submit selected items');
        submitButton.tabIndex = 0;
        submitButton.onclick = () => promptAndSubmit(quantityInput.value);
        selectionBox.appendChild(submitButton);

        const orderNameInput = document.createElement('input');
        orderNameInput.type = 'text';
        orderNameInput.placeholder = 'Order Name';
        orderNameInput.className = 'order-name-input';
        orderNameInput.setAttribute('aria-label', 'Enter order name');
        orderNameInput.tabIndex = 0;
        selectionBox.appendChild(orderNameInput);
    }

    chatMessages.appendChild(selectionBox);
    chatMessages.scrollTop = chatMessages.scrollHeight;
}

async function fetchWithRetry(url, options, retries = MAX_RETRIES) {
    for (let i = 0; i < retries; i++) {
        try {
            const response = await fetch(url, options);
            if (!response.ok) throw new Error(`HTTP error! status: ${response.status}`);
            return await response.json();
        } catch (error) {
            if (i === retries - 1) {
                throw error;
            }
            await new Promise(resolve => setTimeout(resolve, 2000));
        }
    }
}

function fetchMenuItems(dietaryPreference = '', searchTerm = '') {
    const cacheKey = `${dietaryPreference}:${searchTerm}`;
    if (searchCache.has(cacheKey)) {
        const data = searchCache.get(cacheKey);
        displayCachedMenuItems(data, searchTerm, dietaryPreference);
        return;
    }

    const payload = {};
    if (dietaryPreference) payload.dietary_preference = dietaryPreference;
    if (searchTerm) payload.search_term = searchTerm;

    const chatMessages = document.getElementById('chatMessages');
    const spinner = document.createElement('div');
    spinner.className = 'spinner';
    chatMessages.appendChild(spinner);

    fetchWithRetry('/get_menu_items', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(payload)
    })
        .then(data => {
            spinner.remove();
            if (data.error) {
                addMessage('bot', `Error: ${data.error}. Try again!`);
                showToast(`Error: ${data.error}`);
            } else if (data.menu_items.length > 0) {
                searchCache.set(cacheKey, data);
                addMessage('bot', `--- Found ${data.menu_items.length} item${data.menu_items.length > 1 ? 's' : ''} ---`);
                displayItemsList(data.menu_items);
            } else {
                addMessage('bot', `No matches for "${searchTerm || dietaryPreference}". Try "paneer" or "chicken curry"!`);
                showToast('No items found!');
            }
        })
        .catch(error => {
            spinner.remove();
            addMessage('bot', `Connection issue: ${error.message}. Please try again later.`);
            showToast('Connection issue!');
        });
}

function displayCachedMenuItems(data, searchTerm, dietaryPreference) {
    if (data.error) {
        addMessage('bot', `Error: ${data.error}. Try again!`);
        showToast(`Error: ${data.error}`);
    } else if (data.menu_items.length > 0) {
        addMessage('bot', `--- Found ${data.menu_items.length} item${data.menu_items.length > 1 ? 's' : ''} ---`);
        displayItemsList(data.menu_items);
    } else {
        addMessage('bot', `No matches for "${searchTerm || dietaryPreference}". Try "paneer" or "chicken curry"!`);
        showToast('No items found!');
    }
}

function fetchSectorItemDetails(itemName) {
    const cacheKey = `sector:${itemName}`;
    if (searchCache.has(cacheKey)) {
        const data = searchCache.get(cacheKey);
        displayCachedSectorItems(data, itemName);
        return;
    }

    fetchWithRetry('/get_sector_item_details', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ item_name: itemName })
    })
        .then(data => {
            if (data.error) {
                addMessage('bot', `No "${itemName}" found. Try another!`);
                showToast(`No "${itemName}" found`);
            } else {
                searchCache.set(cacheKey, data);
                const details = data.item_details;
                if (selectedItems.some(item => item.name === details.name)) {
                    addMessage('bot', `"${details.name}" already selected!`);
                    showToast(`"${details.name}" already selected`);
                } else {
                    selectedItems.push({ ...details, quantity: 1 });
                    addMessage('bot', `Added "${details.name}"!`);
                    showToast(`Added "${details.name}"`);
                    updateSelectionBox();
                }
            }
        })
        .catch(error => {
            addMessage('bot', `Error for "${itemName}". Please try again later.`);
            showToast(`Error fetching "${itemName}"`);
        });
}

function displayCachedSectorItems(data, itemName) {
    if (data.error) {
        addMessage('bot', `No "${itemName}" found. Try another!`);
        showToast(`No "${itemName}" found`);
    } else {
        const details = data.item_details;
        if (selectedItems.some(item => item.name === details.name)) {
            addMessage('bot', `"${details.name}" already selected!`);
            showToast(`"${details.name}" already selected`);
        } else {
            selectedItems.push({ ...details, quantity: 1 });
            addMessage('bot', `Added "${details.name}"!`);
            showToast(`Added "${details.name}"`);
            updateSelectionBox();
        }
    }
}

function toggleDescription(itemContainer, description, itemName) {
    let descElement = itemContainer.querySelector('.item-description');
    if (!descElement) {
        descElement = document.createElement('p');
        descElement.className = 'item-description';
        descElement.textContent = description;
        itemContainer.querySelector('.selected-item-content').appendChild(descElement);
        itemContainer.dataset.hidden = 'false';
        showToast(`Showing details for ${itemName}`);
    } else {
        descElement.remove();
        itemContainer.dataset.hidden = 'true';
        showToast(`Hid details for ${itemName}`);
    }
}

function displayItemsList(items) {
    const chatMessages = document.getElementById('chatMessages');
    if (!chatMessages) {
        addMessage('bot', 'Display issue. Try again?');
        showToast('Display issue!');
        return;
    }

    const itemsGrid = document.createElement('div');
    itemsGrid.className = 'items-grid';

    items.forEach((item, index) => {
        const itemDiv = document.createElement('article');
        itemDiv.className = 'item-card';

        const img = document.createElement('img');
        img.src = item.image_url || 'https://via.placeholder.com/120?text=Item';
        img.alt = item.name;
        img.className = 'item-image';
        if (index < 3) img.loading = 'eager'; // Preload first 3 images
        itemDiv.appendChild(img);

        const contentDiv = document.createElement('div');
        contentDiv.className = 'item-content';

        const nameDiv = document.createElement('div');
        nameDiv.textContent = item.name;
        nameDiv.className = 'item-name';
        contentDiv.appendChild(nameDiv);

        const fields = [
            { label: 'Price', value: item.price ? `$${item.price.toFixed(2)}` : 'N/A' },
            { label: 'Veg/Non-Veg', value: item.veg_nonveg },
            { label: 'Spice', value: item.spice_levels },
            { label: 'Category', value: item.category },
            { label: 'Ingredients', value: item.ingredients },
            { label: 'Nutrition', value: item.nutritional_info },
            { label: 'Sector', value: item.sector },
            { label: 'Dynamic', value: item.dynamic_dish ? 'Yes' : 'No' }
        ];
        fields.forEach(field => {
            if (field.value) {
                const p = document.createElement('p');
                p.className = 'item-field';
                p.innerHTML = `<strong>${field.label}:</strong> ${field.value}`;
                contentDiv.appendChild(p);
            }
        });

        itemDiv.appendChild(contentDiv);

        const buttonContainer = document.createElement('div');
        buttonContainer.className = 'button-container';

        const addButton = document.createElement('button');
        addButton.textContent = 'Add';
        addButton.className = 'add-button';
        addButton.setAttribute('aria-label', `Add ${item.name} to selection`);
        addButton.tabIndex = 0;
        addButton.onclick = () => {
            const selectedItem = {
                name: item.name,
                image_url: item.image_url || '',
                category: item.category || 'Not specified',
                description: item.description || 'No description available',
                source: item.source,
                quantity: 1,
                ingredients: item.ingredients,
                nutritional_info: item.nutritional_info,
                price: item.price,
                sector: item.sector,
                spice_levels: item.spice_levels,
                veg_nonveg: item.veg_nonveg,
                dynamic_dish: item.dynamic_dish
            };
            if (selectedItems.some(existing => existing.name === selectedItem.name)) {
                addMessage('bot', `"${selectedItem.name}" already selected!`);
                showToast(`"${selectedItem.name}" already selected`);
            } else {
                selectedItems.push(selectedItem);
                addMessage('bot', `Added "${selectedItem.name}"!`);
                showToast(`Added "${selectedItem.name}"`);
                updateSelectionBox();
            }
        };
        buttonContainer.appendChild(addButton);

        itemDiv.appendChild(buttonContainer);
        itemsGrid.appendChild(itemDiv);
    });

    chatMessages.appendChild(itemsGrid);
    chatMessages.scrollTop = chatMessages.scrollHeight;
}

function displayOptions(options) {
    const chatMessages = document.getElementById('chatMessages');
    if (!chatMessages) {
        console.error('Chat messages container not found!');
        return;
    }
    const optionsDiv = document.createElement('div');
    optionsDiv.className = 'options-container';

    options.forEach(opt => {
        const button = document.createElement('button');
        button.textContent = opt.text;
        button.className = `option-button ${opt.class}`;
        button.setAttribute('aria-label', `Select ${opt.text} dishes`);
        button.tabIndex = 0;
        button.onclick = () => {
            addMessage('user', opt.text, true);
            conversation.push({ role: 'user', message: opt.text });
            selectionBoxVisible = true;
            handleResponse(opt.text);
            updateSelectionBox();
            showToast(`Selected ${opt.text}`);
        };
        optionsDiv.appendChild(button);
    });

    const backButton = document.createElement('button');
    backButton.textContent = 'Back';
    backButton.className = 'option-button';
    backButton.setAttribute('aria-label', 'Reset conversation');
    backButton.tabIndex = 0;
    backButton.onclick = () => resetConversation();
    optionsDiv.appendChild(backButton);

    chatMessages.appendChild(optionsDiv);
}

function promptAndSubmit(quantity) {
    const orderNameInput = document.querySelector('.order-name-input');
    const customOrderName = orderNameInput ? orderNameInput.value.trim() : '';
    const qty = parseInt(quantity);
    if (isNaN(qty) || qty <= 0) {
        addMessage('bot', 'Please enter a valid quantity (1 or more)!');
        showToast('Invalid quantity!');
        return;
    }
    if (confirm(`Submit ${selectedItems.length} items with default quantity ${qty}?`)) {
        submitToSalesforce(customOrderName, qty);
        showToast('Submitting order...');
    } else {
        addMessage('bot', 'Cancelled. Add more items?');
        showToast('Order cancelled');
    }
}

function submitToSalesforce(customOrderName, quantity) {
    if (selectedItems.length === 0) {
        addMessage('bot', 'No items selected! Add some dishes! 😊');
        showToast('No items selected');
        return;
    }

    const itemsToSubmit = selectedItems.map(item => ({
        name: item.name,
        category: item.category || 'Not specified',
        description: item.description || 'No description available',
        image_url: item.image_url || '',
        quantity: item.quantity || parseInt(quantity) || 1
    }));

    fetchWithRetry('/submit_items', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ items: itemsToSubmit, custom_order_name: customOrderName })
    })
        .then(data => {
            if (data.error) {
                addMessage('bot', `Submission failed: ${data.error}. Try again?`);
                showToast(`Submission failed: ${data.error}`);
            } else {
                addMessage('bot', `Order "${customOrderName || 'Order'}" with ${itemsToSubmit.length} items submitted! What's next?`);
                selectedItems = [];
                updateSelectionBox();
                showToast('Order submitted successfully!');
            }
        })
        .catch(error => {
            addMessage('bot', `Submission error: ${error.message}. Please try again later.`);
            showToast('Submission error!');
        });
}

function resetConversation() {
    const userName = conversation.length > 1 ? conversation[1].message : 'Friend';
    conversation = [
        { role: 'bot', message: `Hello! I’m Chef Bot, your culinary assistant! What’s your name?` },
        { role: 'user', message: userName },
        { role: 'bot', message: `Hi ${userName}! 🍳 Search for a dish or choose a preference below!` }
    ];
    selectedItems = [];
    selectionBoxVisible = true;
    const chatMessages = document.getElementById('chatMessages');
    chatMessages.innerHTML = '';
    conversation.forEach(msg => addMessage(msg.role, msg.message));
    displayOptions([
        { text: 'Vegetarian', class: 'green' },
        { text: 'Non-Vegetarian', class: 'red' },
        { text: 'Both', class: 'gray' }
    ]);
    updateSelectionBox();
    showToast('Conversation reset');
}

document.getElementById('userInput').addEventListener('keypress', (e) => {
    if (e.key === 'Enter') sendMessage();
});

console.log('Chef Bot script loaded!');