{% extends "base.html" %}

{% block title %}Chat - Appointment {{ appointment.id }}{% endblock %}

{% block extra_css %}
<style>
    .chat-container {
        height: calc(100vh - 200px);
        display: flex;
        flex-direction: column;
    }

    .chat-messages {
        flex: 1;
        overflow-y: auto;
        padding: 24px;
        background: linear-gradient(to bottom, rgba(248, 250, 252, 0.5), rgba(241, 245, 249, 0.5));
        border-radius: 16px;
        margin-bottom: 20px;
        scroll-behavior: smooth;
    }

    .chat-messages::-webkit-scrollbar {
        width: 8px;
    }

    .chat-messages::-webkit-scrollbar-track {
        background: rgba(0, 0, 0, 0.05);
        border-radius: 10px;
    }

    .chat-messages::-webkit-scrollbar-thumb {
        background: rgba(16, 185, 129, 0.3);
        border-radius: 10px;
    }

    .chat-messages::-webkit-scrollbar-thumb:hover {
        background: rgba(16, 185, 129, 0.5);
    }

    .message {
        margin-bottom: 15px;
        display: flex;
        align-items: flex-start;
    }

    .message.own {
        justify-content: flex-end;
    }

    .message-content {
        max-width: 70%;
        padding: 14px 18px;
        border-radius: 20px;
        position: relative;
        box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
        transition: transform 0.2s ease;
    }

    .message-content:hover {
        transform: translateY(-1px);
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
    }

    .message.own .message-content {
        background: linear-gradient(135deg, rgba(16, 185, 129, 0.95) 0%, rgba(5, 150, 105, 0.95) 100%);
        backdrop-filter: blur(20px) saturate(180%);
        -webkit-backdrop-filter: blur(20px) saturate(180%);
        color: white;
        border-bottom-right-radius: 6px;
        box-shadow: 0 4px 12px rgba(16, 185, 129, 0.4);
        margin-left: auto;
    }

    .message.other .message-content {
        background: rgba(255, 255, 255, 0.95);
        backdrop-filter: blur(10px);
        color: #333;
        border: 1px solid rgba(0, 0, 0, 0.08);
        border-bottom-left-radius: 6px;
        box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    }

    .message-header {
        font-size: 0.8rem;
        margin-bottom: 4px;
        opacity: 0.8;
    }

    .message-text {
        margin: 0;
        word-wrap: break-word;
        color: inherit;
    }

    .message-time {
        font-size: 0.7rem;
        opacity: 0.6;
        margin-top: 4px;
        color: inherit;
    }

    .chat-input {
        display: flex;
        gap: 10px;
        align-items: flex-end;
    }

    .chat-input textarea {
        flex: 1;
        resize: none;
        border-radius: 25px;
        border: 2px solid rgba(16, 185, 129, 0.3);
        padding: 14px 20px;
        max-height: 120px;
        background: rgba(255, 255, 255, 0.95);
        backdrop-filter: blur(10px);
        font-size: 0.95rem;
        transition: all 0.3s ease;
    }

    .chat-input textarea:focus {
        outline: none;
        border-color: #10b981;
        box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.1);
        background: #fff;
    }

    .chat-input button {
        border-radius: 50%;
        width: 50px;
        height: 50px;
        display: flex;
        align-items: center;
        justify-content: center;
        background: linear-gradient(135deg, #10b981 0%, #059669 100%);
        border: none;
        color: white;
        cursor: pointer;
        transition: all 0.3s ease;
        box-shadow: 0 4px 12px rgba(16, 185, 129, 0.4);
        flex-shrink: 0;
    }

    .chat-input button:hover {
        transform: scale(1.1);
        box-shadow: 0 6px 20px rgba(16, 185, 129, 0.6);
        background: linear-gradient(135deg, #059669 0%, #047857 100%);
    }

    .chat-input button:active {
        transform: scale(0.95);
    }

    .chat-input button:disabled {
        opacity: 0.5;
        cursor: not-allowed;
        transform: none;
    }

    .typing-indicator {
        font-style: italic;
        color: #666;
        font-size: 0.9rem;
        padding: 10px 20px;
    }

    .prescription-message {
        background: linear-gradient(135deg, rgba(40, 167, 69, 0.15) 0%, rgba(40, 167, 69, 0.05) 100%) !important;
        border-left: 4px solid #28a745 !important;
        border-radius: 20px !important;
    }

    .prescription-label {
        font-weight: bold;
        color: #28a745;
        margin-bottom: 8px;
    }

    .appointment-info {
        background: linear-gradient(135deg, rgba(16, 185, 129, 0.9) 0%, rgba(5, 150, 105, 0.9) 100%);
        color: white;
        padding: 24px;
        border-radius: 16px;
        margin-bottom: 24px;
        box-shadow: 0 4px 16px rgba(16, 185, 129, 0.3);
        backdrop-filter: blur(10px);
    }

    .status-badge {
        font-size: 0.8rem;
        padding: 4px 8px;
        border-radius: 12px;
    }

    .online-indicator {
        width: 8px;
        height: 8px;
        background-color: #28a745;
        border-radius: 50%;
        display: inline-block;
        margin-right: 5px;
    }

    .offline-indicator {
        width: 8px;
        height: 8px;
        background-color: #6c757d;
        border-radius: 50%;
        display: inline-block;
        margin-right: 5px;
    }
</style>
{% endblock %}

{% block content %}
<div class="container py-4">
    <div class="row">
        <div class="col-lg-8">
            <!-- Appointment Info -->
            <div class="appointment-info">
                <div class="row align-items-center">
                    <div class="col-md-8">
                        <h4 class="mb-2">
                            {% if get_current_user().role == 'doctor' %}
                            Chat with {{ appointment.patient.user.name }}
                            {% else %}
                            Chat with {{ appointment.doctor.user.name }}
                            {% endif %}
                        </h4>
                        <p class="mb-1">
                            <i class="fas fa-calendar me-2"></i>
                            {{ appointment.appointment_date.strftime('%B %d, %Y') }} at {{
                            appointment.appointment_time.strftime('%I:%M %p') }}
                        </p>
                        <p class="mb-0">
                            <i class="fas fa-stethoscope me-2"></i>
                            {{ appointment.disease_category }}
                        </p>
                    </div>
                    <div class="col-md-4 text-md-end">
                        <span class="status-badge bg-light text-dark">
                            {{ appointment.status.title() }}
                        </span>
                        <div class="mt-2">
                            <span id="connection-status" class="offline-indicator"></span>
                            <small id="status-text">Connecting...</small>
                        </div>
                    </div>
                </div>
            </div>

            <!-- Chat Container -->
            <div class="card"
                style="border: 1px solid rgba(16, 185, 129, 0.2); border-radius: 16px; box-shadow: 0 4px 16px rgba(0,0,0,0.1); overflow: hidden;">
                <div class="card-body p-0">
                    <div class="chat-container">
                        <!-- Messages Area -->
                        <!-- Chat config data passed via data attributes (avoids Jinja-in-JS lint errors) -->
                        <div id="chat-config" data-appointment-id="{{ appointment.id }}"
                            data-user-id="{{ get_current_user().id }}" data-user-role="{{ get_current_user().role }}"
                            data-appointment-status="{{ appointment.status }}" style="display:none;"></div>

                        <div id="chat-messages" class="chat-messages">
                            <div class="text-center text-muted">
                                <i class="fas fa-comments mb-2" style="font-size: 2rem;"></i>
                                <p>Loading chat history...</p>
                            </div>
                        </div>

                        <!-- Typing Indicator -->
                        <div id="typing-indicator" class="typing-indicator" style="display: none;">
                            <span id="typing-text"></span>
                        </div>

                        <!-- Input Area -->
                        <div class="p-4 border-top"
                            style="background: rgba(255, 255, 255, 0.5); backdrop-filter: blur(10px); border-top: 2px solid rgba(16, 185, 129, 0.1) !important;">
                            {% if appointment.status == 'completed' %}
                            <div class="alert alert-info mb-3"
                                style="background-color: #0dcaf0; color: #000; border-color: #0dcaf0;">
                                <i class="fas fa-info-circle me-2"></i>
                                <strong>Appointment Completed:</strong> Chat is now read-only. You can view previous
                                messages but cannot send new ones.
                            </div>
                            {% else %}
                            {% if get_current_user().role == 'doctor' %}
                            <div class="mb-3">
                                <button id="prescription-btn" class="btn btn-success btn-sm">
                                    <i class="fas fa-prescription me-2"></i>Send Prescription
                                </button>
                            </div>
                            {% endif %}

                            <div class="chat-input">
                                <textarea id="message-input" placeholder="Type your message..." rows="2"
                                    maxlength="1000"></textarea>
                                <button id="send-btn" class="btn btn-primary">
                                    <i class="fas fa-paper-plane"></i>
                                </button>
                            </div>
                            {% endif %}
                        </div>
                    </div>
                </div>
            </div>
        </div>

        <!-- Sidebar -->
        <div class="col-lg-4">
            <!-- Prescription Modal for Doctors -->
            {% if get_current_user().role == 'doctor' %}
            <div class="modal fade" id="prescriptionModal" tabindex="-1">
                <div class="modal-dialog">
                    <div class="modal-content">
                        <div class="modal-header">
                            <h5 class="modal-title">
                                <i class="fas fa-prescription me-2"></i>Send Prescription
                            </h5>
                            <button type="button" class="btn-close" data-bs-dismiss="modal"></button>
                        </div>
                        <div class="modal-body">
                            <div class="mb-3">
                                <label class="form-label">Prescription Details</label>
                                <textarea id="prescription-text" class="form-control" rows="8"
                                    placeholder="Enter prescription details..."></textarea>
                            </div>
                        </div>
                        <div class="modal-footer">
                            <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Cancel</button>
                            <button type="button" id="send-prescription-btn" class="btn btn-success">
                                <i class="fas fa-paper-plane me-2"></i>Send Prescription
                            </button>
                        </div>
                    </div>
                </div>
            </div>
            {% endif %}

            <!-- Appointment Details -->
            <div class="card mb-4">
                <div class="card-header">
                    <h5 class="mb-0">
                        <i class="fas fa-info-circle me-2"></i>Appointment Details
                    </h5>
                </div>
                <div class="card-body">
                    <div class="detail-item mb-3">
                        <strong>Type:</strong><br>
                        <span
                            class="badge badge-{{ 'success' if appointment.appointment_type == 'video' else 'primary' }}">
                            {{ appointment.appointment_type.title() }}
                        </span>
                    </div>

                    <div class="detail-item mb-3">
                        <strong>Symptoms:</strong><br>
                        <small class="text-muted">{{ appointment.symptoms or 'Not provided' }}</small>
                    </div>

                    {% if appointment.notes %}
                    <div class="detail-item mb-3">
                        <strong>Notes:</strong><br>
                        <small class="text-muted">{{ appointment.notes }}</small>
                    </div>
                    {% endif %}

                    <div class="detail-item">
                        <strong>Charges:</strong><br>
                        <span class="text-primary">PKR {{ appointment.charges }}</span>
                    </div>
                </div>
            </div>

            <!-- Quick Actions -->
            <div class="card">
                <div class="card-header">
                    <h5 class="mb-0">
                        <i class="fas fa-bolt me-2"></i>Quick Actions
                    </h5>
                </div>
                <div class="card-body">
                    <div class="d-grid gap-2">
                        <a href="{{ url_for('appointments.view_appointment', appointment_id=appointment.id) }}"
                            class="btn btn-outline-primary btn-sm">
                            <i class="fas fa-eye me-2"></i>View Details
                        </a>
                        {% if get_current_user().role == 'patient' %}
                        <a href="{{ url_for('patients.medical_history') }}" class="btn btn-outline-secondary btn-sm">
                            <i class="fas fa-file-medical me-2"></i>Medical History
                        </a>
                        {% endif %}
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>
{% endblock %}

{% block extra_js %}
<script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/4.7.2/socket.io.js"></script>
<script>
    document.addEventListener('DOMContentLoaded', function () {

        // Read config
        const _cfg = document.getElementById('chat-config');
        const appointmentId = parseInt(_cfg.dataset.appointmentId, 10);
        const currentUserId = parseInt(_cfg.dataset.userId, 10);
        const currentUserRole = _cfg.dataset.userRole;
        const appointmentStatus = _cfg.dataset.appointmentStatus;
        const isCompleted = appointmentStatus === 'completed';

        const chatMessages = document.getElementById('chat-messages');
        const messageInput = document.getElementById('message-input');
        const sendBtn = document.getElementById('send-btn');
        const typingIndicator = document.getElementById('typing-indicator');
        const typingText = document.getElementById('typing-text');
        const connectionStatus = document.getElementById('connection-status');
        const statusText = document.getElementById('status-text');

        // Track rendered message IDs to prevent duplicates
        const renderedIds = new Set();

        // Disable input if appointment is completed
        if (isCompleted && messageInput && sendBtn) {
            messageInput.disabled = true;
            messageInput.placeholder = 'Chat is read-only. Appointment has been completed.';
            sendBtn.disabled = true;
        }

        // ─── 1. HTTP POLLING — Primary mechanism for receiving messages ─────────
        // Polls the DB every 2 seconds. Guaranteed to work regardless of
        // Socket.IO threading issues.
        function pollMessages() {
            fetch(`/appointments/api/messages/${appointmentId}`, {
                method: 'GET',
                credentials: 'same-origin'
            })
                .then(r => r.json())
                .then(data => {
                    if (data.success && data.messages) {
                        let newMessages = false;
                        data.messages.forEach(msg => {
                            if (!renderedIds.has(msg.id)) {
                                renderedIds.add(msg.id);
                                addMessageToChat(msg);
                                newMessages = true;
                            }
                        });
                        if (newMessages) scrollToBottom();

                        // Clear the initial loading placeholder on first poll
                        if (renderedIds.size === 0 && !chatMessages.dataset.cleared) {
                            chatMessages.dataset.cleared = '1';
                            chatMessages.innerHTML = `
                        <div class="text-center text-muted">
                            <i class="fas fa-comments mb-2" style="font-size: 2rem;"></i>
                            <p>No messages yet. Start the conversation!</p>
                        </div>`;
                        }
                    }
                })
                .catch(err => console.warn('Poll error:', err));
        }

        // Initial load then poll every 2 seconds
        pollMessages();
        // Clear placeholder after first poll regardless
        setTimeout(() => {
            if (renderedIds.size === 0) {
                chatMessages.innerHTML = `
                <div class="text-center text-muted">
                    <i class="fas fa-comments mb-2" style="font-size: 2rem;"></i>
                    <p>No messages yet. Start the conversation!</p>
                </div>`;
            }
        }, 3000);
        const pollInterval = setInterval(pollMessages, 2000);

        // ─── 2. SOCKET.IO — Bonus real-time push (when it works) ──────────────
        // Socket.IO is still connected so messages appear instantly when possible.
        // The polling above acts as guaranteed fallback.
        const socket = io({
            transports: ['polling', 'websocket'],
            reconnectionAttempts: 5,
            timeout: 10000
        });

        socket.on('connect_error', function (err) {
            console.warn('Socket.IO connect error (polling fallback active):', err.message);
            statusText.textContent = 'Live (polling)';
            connectionStatus.className = 'online-indicator';
        });

        socket.on('connect', function () {
            console.log('Socket.IO connected');
            connectionStatus.className = 'online-indicator';
            statusText.textContent = 'Connected';
            // Join the room for real-time push notifications
            socket.emit('join_appointment_room', { appointment_id: appointmentId });
        });

        socket.on('disconnect', function () {
            statusText.textContent = 'Live (polling)';
        });

        // Real-time push: add message immediately without waiting for next poll
        socket.on('new_message', function (message) {
            if (!renderedIds.has(message.id)) {
                renderedIds.add(message.id);
                // Remove empty placeholder if present
                const placeholder = chatMessages.querySelector('.text-center.text-muted');
                if (placeholder) placeholder.remove();
                addMessageToChat(message);
                scrollToBottom();
            }
        });

        socket.on('user_typing', function (data) {
            if (data.user_id !== currentUserId) {
                if (data.is_typing) {
                    typingText.textContent = `${data.user_name} is typing...`;
                    typingIndicator.style.display = 'block';
                } else {
                    typingIndicator.style.display = 'none';
                }
            }
        });

        // ─── 3. SENDING — HTTP POST (reliable, no threading issues) ───────────
        let isSending = false;

        function sendMessage() {
            if (isCompleted) {
                showNotification('Chat is read-only. Appointment is completed.', 'error');
                return;
            }
            const message = messageInput.value.trim();
            if (!message || isSending) return;

            isSending = true;
            if (sendBtn) sendBtn.disabled = true;

            fetch('/appointments/api/send-message', {
                method: 'POST',
                headers: { 'Content-Type': 'application/json' },
                credentials: 'same-origin',
                body: JSON.stringify({ appointment_id: appointmentId, message: message })
            })
                .then(r => r.json())
                .then(data => {
                    if (data.success) {
                        messageInput.value = '';
                        stopTyping();
                        // Immediately add own message without waiting for poll
                        if (data.message && !renderedIds.has(data.message.id)) {
                            renderedIds.add(data.message.id);
                            const placeholder = chatMessages.querySelector('.text-center.text-muted');
                            if (placeholder) placeholder.remove();
                            addMessageToChat(data.message);
                            scrollToBottom();
                        }
                    } else {
                        showNotification(data.error || 'Failed to send message', 'error');
                    }
                })
                .catch(err => {
                    console.error('Send error:', err);
                    showNotification('Network error. Please try again.', 'error');
                })
                .finally(() => {
                    isSending = false;
                    if (sendBtn && !isCompleted) sendBtn.disabled = false;
                });
        }

        // Event listeners
        if (!isCompleted) {
            if (sendBtn) sendBtn.addEventListener('click', sendMessage);

            if (messageInput) {
                messageInput.addEventListener('keypress', function (e) {
                    if (e.key === 'Enter' && !e.shiftKey) {
                        e.preventDefault();
                        sendMessage();
                    }
                });

                let typingTimeout;
                let isTyping = false;
                messageInput.addEventListener('input', function () {
                    if (!isTyping) {
                        isTyping = true;
                        socket.emit('typing', { is_typing: true });
                    }
                    clearTimeout(typingTimeout);
                    typingTimeout = setTimeout(() => stopTyping(), 1000);
                });
            }
        }

        function stopTyping() {
            if (typeof isTyping !== 'undefined' && isTyping) {
                isTyping = false;
                socket.emit('typing', { is_typing: false });
            }
        }

        // Prescription (doctors only) — still sent via Socket.IO
        if (currentUserRole === 'doctor') {
            const prescriptionBtn = document.getElementById('prescription-btn');
            if (prescriptionBtn && !isCompleted) {
                const prescriptionModal = new bootstrap.Modal(document.getElementById('prescriptionModal'));
                const prescriptionText = document.getElementById('prescription-text');
                const sendPrescriptionBtn = document.getElementById('send-prescription-btn');

                prescriptionBtn.addEventListener('click', function () {
                    prescriptionModal.show();
                });

                if (sendPrescriptionBtn) {
                    sendPrescriptionBtn.addEventListener('click', function () {
                        const prescription = prescriptionText.value.trim();
                        if (prescription) {
                            socket.emit('send_prescription', { prescription: prescription });
                            prescriptionText.value = '';
                            prescriptionModal.hide();
                        }
                    });
                }
            }
        }

        // ─── Helper functions ──────────────────────────────────────────────────
        function addMessageToChat(message) {
            const messageDiv = document.createElement('div');
            messageDiv.className = `message ${message.user_id === currentUserId ? 'own' : 'other'}`;

            const messageContent = document.createElement('div');
            messageContent.className = 'message-content';
            if (message.type === 'prescription') messageContent.classList.add('prescription-message');

            const messageHeader = document.createElement('div');
            messageHeader.className = 'message-header';
            messageHeader.textContent = message.user_name;

            const messageText = document.createElement('p');
            messageText.className = 'message-text';
            messageText.textContent = message.message;

            const messageTime = document.createElement('div');
            messageTime.className = 'message-time';
            messageTime.textContent = formatTime(message.timestamp);

            messageContent.appendChild(messageHeader);
            messageContent.appendChild(messageText);
            messageContent.appendChild(messageTime);
            messageDiv.appendChild(messageContent);
            chatMessages.appendChild(messageDiv);
        }

        function scrollToBottom() {
            chatMessages.scrollTop = chatMessages.scrollHeight;
        }

        function formatTime(timestamp) {
            const date = new Date(timestamp);
            return date.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
        }

        function showNotification(message, type) {
            const alertClass = type === 'error' ? 'alert-danger' :
                type === 'success' ? 'alert-success' : 'alert-info';
            const notification = document.createElement('div');
            notification.className = `alert ${alertClass} alert-dismissible fade show position-fixed`;
            notification.style.cssText = 'top: 20px; right: 20px; z-index: 9999; min-width: 300px;';
            notification.innerHTML = `${message}<button type="button" class="btn-close" data-bs-dismiss="alert"></button>`;
            document.body.appendChild(notification);
            setTimeout(() => notification.remove(), 5000);
        }

        setTimeout(scrollToBottom, 100);
    });
</script>
{% endblock %}