document.addEventListener('DOMContentLoaded', () => {
    // Starry Background Animation
    const stars = document.createElement('canvas');
    stars.className = 'stars';
    document.body.appendChild(stars);
    const ctx = stars.getContext('2d');
    stars.width = window.innerWidth;
    stars.height = window.innerHeight;
    const starArray = [];
    for (let i = 0; i < 100; i++) {
        starArray.push({
            x: Math.random() * stars.width,
            y: Math.random() * stars.height,
            radius: Math.random() * 2,
            opacity: Math.random()
        });
    }
    function animateStars() {
        ctx.clearRect(0, 0, stars.width, stars.height);
        starArray.forEach(star => {
            ctx.beginPath();
            ctx.arc(star.x, star.y, star.radius, 0, Math.PI * 2);
            ctx.fillStyle = `rgba(255, 255, 255, ${star.opacity})`;
            ctx.fill();
            star.opacity += (Math.random() - 0.5) * 0.05;
            if (star.opacity > 1) star.opacity = 1;
            if (star.opacity < 0) star.opacity = 0;
        });
        requestAnimationFrame(animateStars);
    }
    animateStars();

    // Card Hover Effects
    const cards = document.querySelectorAll(".card");
    cards.forEach(card => {
        card.addEventListener("mouseenter", () => {
            if (!card.classList.contains('shadowed')) {
                card.style.transition = "transform 0.4s ease-in-out";
                card.style.transform = "scale(1.05) rotate(0.5deg)";
            }
        });
        card.addEventListener("mouseleave", () => {
            if (!card.classList.contains('shadowed')) {
                card.style.transform = "scale(1) rotate(0deg)";
            }
        });
    });

    // Window Resize Handler for Canvas
    window.addEventListener('resize', () => {
        stars.width = window.innerWidth;
        stars.height = window.innerHeight;
        starArray.length = 0;
        for (let i = 0; i < 100; i++) {
            starArray.push({
                x: Math.random() * stars.width,
                y: Math.random() * stars.height,
                radius: Math.random() * 2,
                opacity: Math.random()
            });
        }
    });

    // Box Click to Open Modal
    document.querySelectorAll('.function-box').forEach(box => {
        box.addEventListener('click', () => {
            const modalId = box.dataset.modal;
            const modal = document.getElementById(modalId);
            if (modal) {
                modal.classList.remove('hidden');
                document.querySelectorAll('.function-box').forEach(otherBox => {
                    if (otherBox !== box) {
                        otherBox.classList.add('shadowed');
                    }
                });
            }
        });
    });

    // Chatbot Icon Click
    const chatbotIcon = document.querySelector('.chatbot-icon');
    if (chatbotIcon) {
        chatbotIcon.addEventListener('click', () => {
            const chatbotModal = document.getElementById('chatbot-modal');
            if (chatbotModal) {
                chatbotModal.classList.remove('hidden');
            }
        });
    }

    // Close Modal
    document.querySelectorAll('.close-modal').forEach(closeBtn => {
        closeBtn.addEventListener('click', () => {
            const modal = closeBtn.closest('.modal');
            modal.classList.add('hidden');
            const forms = modal.querySelectorAll('form');
            forms.forEach(form => form.reset());
            const responseCards = modal.querySelectorAll('.response-card');
            responseCards.forEach(card => {
                card.classList.add('hidden');
                card.innerHTML = '';
            });
            const spinners = modal.querySelectorAll('.loading-spinner');
            spinners.forEach(spinner => spinner.classList.add('hidden'));
            const dropAreas = modal.querySelectorAll('.drop-area p');
            dropAreas.forEach(p => p.textContent = 'Drop File Here or Click to Choose');
            if (modal.id === 'chatbot-modal') {
                const conversation = document.getElementById('chatbot-conversation');
                if (conversation) {
                    conversation.innerHTML = '';
                }
            }
            document.querySelectorAll('.function-box').forEach(box => {
                box.classList.remove('shadowed');
            });
        });
    });

    // Tab Switching for Summarize and Translate
    document.querySelectorAll('.tab-btn').forEach(btn => {
        btn.addEventListener('click', () => {
            const tab = btn.dataset.tab;
            const modal = btn.closest('.modal');
            modal.querySelectorAll('.tab-btn').forEach(b => b.classList.remove('active'));
            btn.classList.add('active');
            modal.querySelectorAll('.tab-content').forEach(content => {
                content.classList.add('hidden');
                if (content.dataset.tab === tab) content.classList.remove('hidden');
            });
        });
    });

    // File Drop Handler
    window.handleDrop = function(event, dropArea) {
        event.preventDefault();
        const fileInput = dropArea.querySelector('input[type="file"]');
        const files = event.dataTransfer.files;
        if (files.length > 0) {
            fileInput.files = files;
            dropArea.querySelector('p').textContent = `Selected: ${files[0].name}`;
        }
    };

    // File Input Click Handler
    document.querySelectorAll('.drop-area').forEach(dropArea => {
        const fileInput = dropArea.querySelector('input[type="file"]');
        dropArea.addEventListener('click', () => {
            fileInput.click();
        });
        fileInput.addEventListener('change', () => {
            if (fileInput.files.length > 0) {
                dropArea.querySelector('p').textContent = `Selected: ${fileInput.files[0].name}`;
            }
        });
    });

    // Chatbot Form Submission
    const chatbotForm = document.getElementById('chatbot-form');
    if (chatbotForm) {
        chatbotForm.addEventListener('submit', async (e) => {
            e.preventDefault();
            const input = e.target.querySelector('input');
            const message = input.value.trim();
            const spinner = e.target.querySelector('.loading-spinner') || document.createElement('div');
            if (!spinner.classList.contains('loading-spinner')) {
                spinner.className = 'loading-spinner';
                spinner.innerHTML = '<span>Processing...</span>';
                e.target.appendChild(spinner);
            }
            if (!message) return;

            spinner.classList.remove('hidden');
            const conversation = document.getElementById('chatbot-conversation');
            conversation.innerHTML += `<p class="user-message">You: ${message}</p>`;
            conversation.scrollTop = conversation.scrollHeight;
            input.value = '';

            try {
                const response = await fetch('/chat', {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({ message })
                });
                const data = await response.json();
                spinner.classList.add('hidden');
                if (response.ok) {
                    conversation.innerHTML += `<p class="bot-message">Gemini: ${data.response}</p>`;
                } else {
                    conversation.innerHTML += `<p class="bot-message">Error: ${data.detail || 'Unknown error'}</p>`;
                }
                conversation.scrollTop = conversation.scrollHeight;
            } catch (error) {
                spinner.classList.add('hidden');
                conversation.innerHTML += `<p class="bot-message">Error: ${error.message}</p>`;
                conversation.scrollTop = conversation.scrollHeight;
            }
        });
    }

    // Form Submissions for Other Functionalities
    const forms = {
        'summarize-form': { endpoint: '/process', intent: 'summarize' },
        'summarize-file-form': { endpoint: '/process', intent: 'summarize' },
        'translate-text-form': { endpoint: '/process', intent: 'translate' },
        'translate-file-form': { endpoint: '/process', intent: 'file-translate' },
        'file-qa-form': { endpoint: '/process', intent: 'file-qa' },
        'image-caption-form': { endpoint: '/process', intent: 'image-to-text' },
        'visual-qa-form': { endpoint: '/process', intent: 'visual-qa' },
        'visualize-form': { endpoint: '/process', intent: 'visualize' }
    };

    Object.keys(forms).forEach(formId => {
        const form = document.getElementById(formId);
        if (!form) return;
        form.addEventListener('submit', async (e) => {
            e.preventDefault();
            const formData = new FormData();
            const responseCard = form.nextElementSibling;
            let spinner = form.querySelector('.loading-spinner');
            if (!spinner) {
                spinner = document.createElement('div');
                spinner.className = 'loading-spinner hidden';
                spinner.innerHTML = '<span>Processing...</span>';
                form.appendChild(spinner);
            }

            // Collect form data
            const textInput = form.querySelector('textarea, input[type="text"]');
            const fileInput = form.querySelector('input[type="file"]');
            const languageSelect = form.querySelector('select[name="language"]');
            const visualizationSelect = form.querySelector('select[name="visualization-type"]');
            let textValue = textInput && textInput.value.trim() ? textInput.value.trim() : '';

            if (languageSelect && textValue && (formId === 'translate-text-form' || formId === 'translate-file-form')) {
                textValue = `Translate to ${languageSelect.value}: ${textValue}`;
            }
            if (textValue) {
                formData.append('text', textValue);
            }
            if (fileInput && fileInput.files.length > 0) {
                formData.append('file', fileInput.files[0]);
            }
            if (visualizationSelect) {
                formData.append('text', visualizationSelect.value);
            }

            // Validate input
            if (!textValue && (!fileInput || fileInput.files.length === 0)) {
                responseCard.classList.remove('hidden');
                responseCard.innerHTML = '<p class="error">Please provide text or a file.</p>';
                return;
            }

            spinner.classList.remove('hidden');
            responseCard.classList.add('hidden');
            responseCard.innerHTML = '';

            // Display uploaded image locally for caption and visual QA
            let localImageUrl = '';
            if (fileInput && fileInput.files.length > 0 && (formId === 'image-caption-form' || formId === 'visual-qa-form')) {
                const file = fileInput.files[0];
                localImageUrl = await new Promise(resolve => {
                    const reader = new FileReader();
                    reader.onload = () => resolve(reader.result);
                    reader.readAsDataURL(file);
                });
            }

            try {
                const response = await fetch(forms[formId].endpoint, {
                    method: 'POST',
                    body: formData
                });
                const data = await response.json();
                spinner.classList.add('hidden');
                responseCard.classList.remove('hidden');
                if (response.ok) {
                    let responseText = data.response;
                    if (data.type === 'visualization_code') {
                        responseText = `<pre>${responseText}</pre>`;
                    } else if (data.type === 'caption' || data.type === 'visual_qa') {
                        responseText = `${responseText}<br><img src="${localImageUrl}" alt="Uploaded Image" style="max-width: 100%; margin-top: 10px;">`;
                    } else if (data.type === 'file_qa' || data.type === 'file_translation') {
                        responseText = `${responseText}<br><small>File: ${data.additional_data.file_name}</small>`;
                    }
                    responseCard.innerHTML = `<p>${responseText}</p>`;
                    if (data.message) {
                        responseCard.innerHTML += `<p><small>${data.message}</small></p>`;
                    }
                } else {
                    responseCard.innerHTML = `<p class="error">Error: ${data.detail || 'Unknown error'}</p>`;
                }
            } catch (error) {
                spinner.classList.add('hidden');
                responseCard.classList.remove('hidden');
                responseCard.innerHTML = `<p class="error">Error: ${error.message}</p>`;
            }
        });
    });
});