/**
 * KI Chat Widget - Functional Chat Interface
 * Integrates with existing chat widget in KI Chat card
 * Connects to N8N webhook via send.php
 */

class KIChat {
    constructor() {
        this.sessionId = this.generateSessionId();
        this.isTyping = false;
        this.messages = [];
        
        this.init();
    }
    
    init() {
        this.bindEvents();
        this.loadChatHistory();
        this.setupExistingChat();
    }
    
    generateSessionId() {
        return 'chat_' + Date.now() + '_' + Math.random().toString(36).substr(2, 9);
    }
    
    bindEvents() {
        // Chat button clicks
        const chatBtn = document.getElementById('chatBtn');
        const interactionBtn = document.querySelector('#chatInteraction .interaction-btn');
        
        if (chatBtn) {
            chatBtn.addEventListener('click', () => this.scrollToChat());
        }
        
        if (interactionBtn) {
            interactionBtn.addEventListener('click', () => this.focusInput());
        }
        
        // Send message on Enter in existing chat
        const existingInput = document.querySelector('#chatInteraction .chat-input');
        if (existingInput) {
            existingInput.addEventListener('keypress', (e) => {
                if (e.key === 'Enter') {
                    e.preventDefault();
                    this.sendMessage();
                }
            });
        }
        
        // Send button click
        const sendBtn = document.querySelector('#chatInteraction .chat-send');
        if (sendBtn) {
            sendBtn.addEventListener('click', () => this.sendMessage());
        }
    }
    
    setupExistingChat() {
        const chatMessages = document.querySelector('#chatInteraction .chat-messages');
        const chatInput = document.querySelector('#chatInteraction .chat-input');
        const sendBtn = document.querySelector('#chatInteraction .chat-send');
        
        // Add click event listener to the send button
        if (sendBtn) {
            sendBtn.addEventListener('click', () => this.sendMessage());
        }
        
        // Add welcome message
        if (this.messages.length === 0 && chatMessages) {
            this.addMessage('ki', 'Hallo! Ich bin Ihr KI-Assistent. Wie kann ich Ihnen helfen?');
        }
        
        this.updateChatDisplay();
    }
    
    scrollToChat() {
        const chatInteraction = document.getElementById('chatInteraction');
        if (chatInteraction) {
            chatInteraction.scrollIntoView({ behavior: 'smooth', block: 'center' });
            setTimeout(() => this.focusInput(), 500);
        }
    }
    
    focusInput() {
        const inputField = document.querySelector('#chatInteraction .chat-input');
        if (inputField) {
            inputField.focus();
        }
    }
    
    addMessage(sender, text, timestamp = Date.now()) {
        this.messages.push({
            sender: sender,
            text: text,
            timestamp: timestamp
        });
        
        // Keep only last 50 messages
        if (this.messages.length > 50) {
            this.messages = this.messages.slice(-50);
        }
        
        this.saveChatHistory();
        this.updateChatDisplay();
    }
    
    updateChatDisplay() {
        const chatMessages = document.querySelector('#chatInteraction .chat-messages');
        if (chatMessages) {
            // Clear existing messages except typing indicator
            const typingIndicator = chatMessages.querySelector('.typing-indicator');
            chatMessages.innerHTML = '';
            
            // Add all messages
            this.messages.forEach(msg => {
                const messageDiv = document.createElement('div');
                messageDiv.className = `chat-message ${msg.sender}`;
                messageDiv.innerHTML = `
                    <div class="message-content">${this.escapeHtml(msg.text)}</div>
                    <div class="message-time">${this.formatTime(msg.timestamp)}</div>
                `;
                chatMessages.appendChild(messageDiv);
            });
            
            // Re-add typing indicator if needed
            if (typingIndicator && this.isTyping) {
                chatMessages.appendChild(typingIndicator);
            }
            
            this.scrollToBottom();
        }
    }
    
    async sendMessage() {
        const inputField = document.querySelector('#chatInteraction .chat-input');
        const message = inputField?.value?.trim();
        
        if (!message || this.isTyping) return;
        
        // Add user message
        this.addMessage('user', message);
        inputField.value = '';
        
        // Show typing indicator
        this.showTypingIndicator();
        this.isTyping = true;
        
        try {
            const response = await fetch('/scripts/add/send.php', {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/json',
                },
                body: JSON.stringify({
                    type: 'chat',
                    message: message,
                    session_id: this.sessionId
                })
            });
            
            const data = await response.json();
            
            if (data.success) {
                this.addMessage('ki', data.data.ai_response, data.data.timestamp);
            } else {
                this.addMessage('ki', 'Entschuldigung, es gab ein Problem. Bitte versuchen Sie es später erneut.');
            }
        } catch (error) {
            console.error('Chat error:', error);
            this.addMessage('ki', 'Verbindung zum Server fehlgeschlagen. Bitte überprüfen Sie Ihre Internetverbindung.');
        } finally {
            this.hideTypingIndicator();
            this.isTyping = false;
        }
    }
    
    showTypingIndicator() {
        const chatMessages = document.querySelector('#chatInteraction .chat-messages');
        if (chatMessages && !chatMessages.querySelector('.typing-indicator')) {
            const typingHTML = `
                <div class="chat-message ki typing">
                    <div class="message-content">
                        <div class="typing-indicator">
                            <span></span>
                            <span></span>
                            <span></span>
                        </div>
                    </div>
                </div>
            `;
            chatMessages.insertAdjacentHTML('beforeend', typingHTML);
            this.scrollToBottom();
        }
    }
    
    hideTypingIndicator() {
        const typingIndicator = document.querySelector('#chatInteraction .typing');
        if (typingIndicator) {
            typingIndicator.remove();
        }
    }
    
    scrollToBottom() {
        const chatMessages = document.querySelector('#chatInteraction .chat-messages');
        if (chatMessages) {
            chatMessages.scrollTop = chatMessages.scrollHeight;
        }
    }
    
    saveChatHistory() {
        try {
            localStorage.setItem(`ki_chat_${this.sessionId}`, JSON.stringify(this.messages));
        } catch (e) {
            console.warn('Could not save chat history:', e);
        }
    }
    
    loadChatHistory() {
        try {
            const saved = localStorage.getItem(`ki_chat_${this.sessionId}`);
            if (saved) {
                this.messages = JSON.parse(saved);
            }
        } catch (e) {
            console.warn('Could not load chat history:', e);
        }
    }
    
    formatTime(timestamp) {
        const date = new Date(timestamp);
        return date.toLocaleTimeString('de-DE', { 
            hour: '2-digit', 
            minute: '2-digit' 
        });
    }
    
    escapeHtml(text) {
        const div = document.createElement('div');
        div.textContent = text;
        return div.innerHTML;
    }
}

// Initialize chat when DOM is ready
document.addEventListener('DOMContentLoaded', () => {
    window.kiChat = new KIChat();
});

// Add CSS for enhanced chat functionality
const chatStyles = `
#chatInteraction {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

#chatInteraction h3 {
    margin: 0;
    font-size: 24px;
    color: var(--primary-dark);
    text-align: center;
}

#chatInteraction p {
    margin: 0;
    color: var(--primary-mid);
    text-align: center;
    font-size: 16px;
    line-height: 1.5;
}

#chatInteraction .card-visual {
    height: 400px;
}

#chatInteraction .chat-window {
    width: 100%;
    height: 400px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(79, 71, 71, 0.1);
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

#chatInteraction .chat-header {
    background: linear-gradient(135deg, var(--accent-teal), var(--accent-green));
    color: white;
    padding: 15px 20px;
    font-weight: 600;
    font-size: 16px;
}

#chatInteraction .chat-messages {
    flex: 1;
    padding: 20px;
    overflow-y: auto !important;
    background: transparent;
    max-height: 300px !important;
    display: flex;
    flex-direction: column;
    gap: 12px;
    min-height: 0;
    align-items: flex-start;
    justify-content: flex-start;
}

#chatInteraction .chat-message {
    display: flex;
    width: 100%;
    background: transparent;
}

#chatInteraction .chat-message.user {
    justify-content: flex-end;
}

#chatInteraction .chat-message.ki {
    justify-content: flex-start;
}

#chatInteraction .message-content {
    background: transparent;
    padding: 12px 16px;
    border-radius: 16px;
    box-shadow: none;
    word-wrap: break-word;
    line-height: 1.4;
    max-width: 70%;
    display: inline-block;
    text-align: left;
}

#chatInteraction .chat-message.user .message-content {
    background: var(--accent-green);
    color: white;
}

#chatInteraction .chat-message.ki .message-content {
    background: var(--accent-green);
    color: white;
}

#chatInteraction .message-time {
    font-size: 10px;
    color: #666;
    margin-top: 4px;
    padding: 0 16px;
}

#chatInteraction .chat-message.ki .message-time {
    text-align: left;
}

#chatInteraction .chat-message.user .message-time {
    text-align: right;
}

#chatInteraction .chat-input-container .interaction-btn {
    flex-shrink: 0;
    padding: 12px 20px;
    font-size: 14px;
}

#chatInteraction .chat-send {
    background: var(--accent-teal);
    color: white;
    border: none;
    border-radius: 50%;
    width: 45px;
    height: 45px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    flex-shrink: 0;
    padding: 0;
    margin-left: 8px;
    box-shadow: 0 2px 8px rgba(38, 166, 154, 0.3);
}

#chatInteraction .chat-send:hover {
    background: #1e8e82;
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(38, 166, 154, 0.4);
}

#chatInteraction .chat-send:active {
    transform: scale(0.95);
}

#chatInteraction .chat-send img {
    width: 22px;
    height: 22px;
    filter: brightness(0) invert(1);
    object-fit: contain;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    #chatInteraction .card-visual {
        min-height: 350px;
    }
    
    #chatInteraction .chat-messages {
        min-height: 200px;
        padding: 15px;
    }
    
    #chatInteraction .chat-input-container {
        padding: 12px 15px;
    }
    
    #chatInteraction .chat-input {
        padding: 10px 14px;
    }
    
    #chatInteraction .chat-send {
        padding: 10px 16px;
        font-size: 13px;
    }
}
`;

// Inject CSS
const styleSheet = document.createElement('style');
styleSheet.textContent = chatStyles;
document.head.appendChild(styleSheet);