/**
 * JCHAT Web Client - JMAP-based Chat Application
 */

class JChatClient {
    constructor() {
        this.serverUrl = JChatConfig.API_BASE_URL;
        this.session = null;
        this.conversations = new Map();
        this.messages = new Map();
        this.currentConversationId = null;
        this.userId = 'user1'; // Demo user
        
        this.init();
    }

    async init() {
        try {
            await this.loadSession();
            await this.loadConversations();
            this.updateConnectionStatus('Connected', 'success');
            
            // Set up polling for new messages (in production, use EventSource/WebSockets)
            this.startPolling();
        } catch (error) {
            console.error('Failed to initialize client:', error);
            this.updateConnectionStatus('Connection failed', 'error');
        }
    }

    async loadSession() {
        const response = await fetch(`${this.serverUrl}/jmap/session`);
        if (!response.ok) {
            throw new Error('Failed to load session');
        }
        this.session = await response.json();
        console.log('Session loaded:', this.session);
    }

    async makeJMAPRequest(methodCalls) {
        const request = {
            using: ['urn:ietf:params:jmap:core', 'urn:ietf:params:jmap:chat'],
            methodCalls: methodCalls
        };

        const response = await fetch(`${this.serverUrl}/jmap/api`, {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json'
            },
            body: JSON.stringify(request)
        });

        if (!response.ok) {
            throw new Error(`JMAP request failed: ${response.status}`);
        }

        return await response.json();
    }

    async loadConversations() {
        try {
            // For demo, create a sample conversation if none exist
            const queryResponse = await this.makeJMAPRequest([
                ['Conversation/query', { accountId: 'default' }, 'q1']
            ]);

            const queryResult = queryResponse.methodResponses[0][1];
            
            if (queryResult.ids.length === 0) {
                // Create a demo conversation
                await this.createDemoConversation();
                return this.loadConversations();
            }

            // Load conversation details
            const getResponse = await this.makeJMAPRequest([
                ['Conversation/get', { 
                    accountId: 'default',
                    ids: queryResult.ids
                }, 'g1']
            ]);

            const conversations = getResponse.methodResponses[0][1].list;
            
            this.conversations.clear();
            conversations.forEach(conv => {
                this.conversations.set(conv.id, conv);
            });

            this.renderConversations();
        } catch (error) {
            console.error('Failed to load conversations:', error);
            this.showStatus('Failed to load conversations', 'error');
        }
    }

    async createDemoConversation() {
        try {
            const response = await this.makeJMAPRequest([
                ['Conversation/set', {
                    accountId: 'default',
                    create: {
                        'demo1': {
                            title: 'Demo Conversation',
                            participantIds: [this.userId, 'user2']
                        }
                    }
                }, 'c1']
            ]);

            console.log('Demo conversation created:', response);
        } catch (error) {
            console.error('Failed to create demo conversation:', error);
        }
    }

    async loadMessages(conversationId) {
        try {
            // Query messages for the conversation
            const queryResponse = await this.makeJMAPRequest([
                ['Message/query', {
                    accountId: 'default',
                    filter: { inConversation: conversationId },
                    sort: [{ property: 'sentAt', isAscending: true }]
                }, 'mq1']
            ]);

            const messageIds = queryResponse.methodResponses[0][1].ids;
            
            if (messageIds.length === 0) {
                this.messages.set(conversationId, []);
                this.renderMessages();
                return;
            }

            // Get message details
            const getResponse = await this.makeJMAPRequest([
                ['Message/get', {
                    accountId: 'default',
                    ids: messageIds
                }, 'mg1']
            ]);

            const messages = getResponse.methodResponses[0][1].list;
            this.messages.set(conversationId, messages);
            this.renderMessages();
        } catch (error) {
            console.error('Failed to load messages:', error);
            this.showStatus('Failed to load messages', 'error');
        }
    }

    renderConversations() {
        const container = document.getElementById('conversations');
        container.innerHTML = '';

        this.conversations.forEach(conv => {
            const div = document.createElement('div');
            div.className = 'conversation';
            div.onclick = () => this.selectConversation(conv.id);
            
            if (conv.id === this.currentConversationId) {
                div.classList.add('active');
            }

            div.innerHTML = `
                <div class="conversation-title">${conv.title || 'Untitled Conversation'}</div>
                <div class="conversation-preview">
                    ${conv.lastMessageAt ? `Last: ${new Date(conv.lastMessageAt).toLocaleTimeString()}` : 'No messages'}
                </div>
            `;

            container.appendChild(div);
        });
    }

    renderMessages() {
        const container = document.getElementById('messages');
        const messages = this.messages.get(this.currentConversationId) || [];

        if (messages.length === 0) {
            container.innerHTML = `
                <div class="empty-state">
                    <h3>No messages yet</h3>
                    <p>Start the conversation by sending a message</p>
                </div>
            `;
            return;
        }

        container.innerHTML = '';

        messages.forEach(msg => {
            const div = document.createElement('div');
            div.className = 'message';
            
            if (msg.senderId === this.userId) {
                div.classList.add('sent');
            }

            const sentTime = new Date(msg.sentAt).toLocaleTimeString();
            
            div.innerHTML = `
                <div class="message-header">${sentTime}</div>
                <div class="message-body">${this.escapeHtml(msg.body)}</div>
            `;

            container.appendChild(div);
        });

        // Scroll to bottom
        container.scrollTop = container.scrollHeight;
    }

    async selectConversation(conversationId) {
        this.currentConversationId = conversationId;
        const conversation = this.conversations.get(conversationId);
        
        // Update UI
        document.getElementById('conversationTitle').textContent = conversation.title || 'Untitled Conversation';
        document.getElementById('compose').style.display = 'flex';
        
        // Re-render conversations to show selection
        this.renderConversations();
        
        // Load and render messages
        await this.loadMessages(conversationId);
    }

    async sendMessage() {
        const input = document.getElementById('messageInput');
        const message = input.value.trim();
        
        if (!message || !this.currentConversationId) {
            return;
        }

        try {
            const response = await this.makeJMAPRequest([
                ['Message/set', {
                    accountId: 'default',
                    create: {
                        'temp1': {
                            conversationId: this.currentConversationId,
                            body: message,
                            senderId: this.userId
                        }
                    }
                }, 'm1']
            ]);

            console.log('Message sent:', response);
            
            // Clear input
            input.value = '';
            
            // Reload messages
            await this.loadMessages(this.currentConversationId);
            await this.loadConversations(); // Update conversation preview
            
        } catch (error) {
            console.error('Failed to send message:', error);
            this.showStatus('Failed to send message', 'error');
        }
    }

    async createNewConversation() {
        const title = prompt('Enter conversation title:');
        if (!title) return;

        try {
            const response = await this.makeJMAPRequest([
                ['Conversation/set', {
                    accountId: 'default',
                    create: {
                        'new1': {
                            title: title,
                            participantIds: [this.userId]
                        }
                    }
                }, 'nc1']
            ]);

            console.log('New conversation created:', response);
            await this.loadConversations();
            
        } catch (error) {
            console.error('Failed to create conversation:', error);
            this.showStatus('Failed to create conversation', 'error');
        }
    }

    startPolling() {
        // Simple polling for demo - in production use EventSource or WebSockets
        setInterval(async () => {
            if (this.currentConversationId) {
                await this.loadMessages(this.currentConversationId);
            }
        }, 5000); // Poll every 5 seconds
    }

    updateConnectionStatus(text, type) {
        const statusElement = document.getElementById('connectionStatus');
        statusElement.textContent = text;
        statusElement.className = type;
    }

    showStatus(message, type) {
        // Remove existing status
        const existing = document.querySelector('.status');
        if (existing) {
            existing.remove();
        }

        // Create new status
        const status = document.createElement('div');
        status.className = `status ${type}`;
        status.textContent = message;
        document.body.appendChild(status);

        // Auto-remove after 3 seconds
        setTimeout(() => {
            if (status.parentNode) {
                status.remove();
            }
        }, 3000);
    }

    escapeHtml(text) {
        const div = document.createElement('div');
        div.textContent = text;
        return div.innerHTML;
    }
}

// Global functions for HTML event handlers
window.jchatClient = new JChatClient();

window.sendMessage = () => {
    window.jchatClient.sendMessage();
};

window.createNewConversation = () => {
    window.jchatClient.createNewConversation();
};

window.handleKeyPress = (event) => {
    if (event.key === 'Enter') {
        window.jchatClient.sendMessage();
    }
};