// Chat UI Module - Threat-aware chat with GPT
(function () {
    const { state } = APP.core;
    const { $ } = APP.core.utils;
    const { log } = APP.ui.logging;

    let chatHistory = [];

    /**
     * Initialize the chat module.
     */
    function init() {
        const chatInput = $("#chatInput");
        const chatSend = $("#chatSend");

        if (chatSend) {
            chatSend.addEventListener("click", sendMessage);
        }

        if (chatInput) {
            chatInput.addEventListener("keydown", (e) => {
                if (e.key === "Enter" && !e.shiftKey) {
                    e.preventDefault();
                    sendMessage();
                }
            });
        }

        // Toggle chat panel
        const chatToggle = $("#chatToggle");
        const chatPanel = $("#chatPanel");
        if (chatToggle && chatPanel) {
            chatToggle.addEventListener("click", () => {
                chatPanel.classList.toggle("collapsed");
                chatToggle.textContent = chatPanel.classList.contains("collapsed")
                    ? "▼ Chat"
                    : "▲ Close Chat";
            });
        }
    }

    /**
     * Send a chat message about current threats.
     */
    async function sendMessage() {
        const chatInput = $("#chatInput");
        const chatMessages = $("#chatMessages");

        if (!chatInput || !chatMessages) return;

        const question = chatInput.value.trim();
        if (!question) {
            log("Please enter a question.", "w");
            return;
        }

        // Check if we have detections
        if (!state.detections || state.detections.length === 0) {
            appendMessage("system", "No detections yet. Run Detect first to analyze the scene.");
            return;
        }

        // Add user message to UI
        appendMessage("user", question);
        chatInput.value = "";
        chatInput.disabled = true;

        // Show loading indicator
        const loadingId = appendMessage("assistant", "Analyzing scene...", true);

        try {
            const response = await APP.api.client.chatAboutThreats(question, state.detections);

            // Remove loading message
            removeMessage(loadingId);

            if (response.response) {
                appendMessage("assistant", response.response);
                chatHistory.push({ role: "user", content: question });
                chatHistory.push({ role: "assistant", content: response.response });
            } else if (response.error || response.detail) {
                appendMessage("system", `Error: ${response.error || response.detail}`);
            }
        } catch (err) {
            removeMessage(loadingId);
            appendMessage("system", `Failed to get response: ${err.message}`);
            log(`Chat error: ${err.message}`, "e");
        } finally {
            chatInput.disabled = false;
            chatInput.focus();
        }
    }

    /**
     * Append a message to the chat display.
     */
    function appendMessage(role, content, isLoading = false) {
        const chatMessages = $("#chatMessages");
        if (!chatMessages) return null;

        const msgId = `msg-${Date.now()}`;
        const msgDiv = document.createElement("div");
        msgDiv.className = `chat-message chat-${role}`;
        msgDiv.id = msgId;

        if (isLoading) {
            msgDiv.classList.add("loading");
        }

        // Format content with line breaks
        const formatted = content.replace(/\n/g, "<br>");

        const icon = role === "user" ? "YOU" : role === "assistant" ? "TAC" : "SYS";
        msgDiv.innerHTML = `<span class="chat-icon">${icon}</span><span class="chat-content">${formatted}</span>`;

        chatMessages.appendChild(msgDiv);
        chatMessages.scrollTop = chatMessages.scrollHeight;

        return msgId;
    }

    /**
     * Remove a message by ID.
     */
    function removeMessage(msgId) {
        const msg = document.getElementById(msgId);
        if (msg) msg.remove();
    }

    /**
     * Clear chat history.
     */
    function clearChat() {
        const chatMessages = $("#chatMessages");
        if (chatMessages) {
            chatMessages.innerHTML = "";
        }
        chatHistory = [];
    }

    // Export
    APP.ui = APP.ui || {};
    APP.ui.chat = {
        init,
        sendMessage,
        clearChat
    };

    // Auto-init on DOMContentLoaded
    if (document.readyState === "loading") {
        document.addEventListener("DOMContentLoaded", init);
    } else {
        init();
    }
})();