// digital.human.video.js
import * as webllm from "https://esm.run/@mlc-ai/web-llm";

// Ensure the script runs after the DOM is fully loaded
document.addEventListener("DOMContentLoaded", () => {
  // Initialize the Digital Human Video Assistant section
  const videoMessages = [
    {
      content: "You are Aged Guru, an intelligent assistant skilled in video analysis and related interdisciplinary studies. Provide insightful and comprehensive answers to complex video-related questions.",
      role: "system"
    }
  ];

  const videoAvailableModels = webllm.prebuiltAppConfig.model_list.map(
    (m) => m.model_id
  );
  let videoSelectedModel = "Phi-3.5-vision-instruct-q4f16_1-MLC"; // Default model

  function videoUpdateEngineInitProgressCallback(report) {
    console.log("Digital Human Video Initialize", report.progress);
    // Instead of updating a status span, log the progress
    logMessage(`Model Initialization Progress: ${report.text}`, "system");
  }

  const videoEngine = new webllm.MLCEngine();
  videoEngine.setInitProgressCallback(videoUpdateEngineInitProgressCallback);

  let videoIsGenerating = false; // Flag to prevent multiple generations

  async function videoInitializeWebLLMEngine() {
    logMessage("Model initialization started.", "system");
    document.getElementById("video-loading-spinner").classList.remove("hidden"); // Show spinner
    videoSelectedModel = document.getElementById("video-model-selection").value;
    const config = {
      temperature: 0.7, // Adjusted for more precise answers
      top_p: 0.9
    };
    try {
      await videoEngine.reload(videoSelectedModel, config);
      document.getElementById("video-selected-model").textContent = videoSelectedModel;
      document.getElementById("video-start_button").disabled = false;
      document.getElementById("video-text-input").disabled = false; // Enable text input after initialization
      document.getElementById("video-submit-button").disabled = false; // Enable submit button after initialization
      document.getElementById("video-speech-controls").disabled = false; // Enable speech controls after initialization
      document.getElementById("video-configuration").classList.remove("hidden");
      logMessage("Model initialized successfully.", "system");
    } catch (error) {
      console.error("Error initializing the model:", error);
      alert("Failed to initialize the model. Please try again.");
      logMessage("Failed to initialize the model.", "error");
    } finally {
      document.getElementById("video-loading-spinner").classList.add("hidden"); // Hide spinner
    }
  }

  async function videoStreamingGenerating(messages, onUpdate, onFinish, onError) {
    if (videoIsGenerating) {
      console.warn("Video Generation already in progress.");
      return;
    }
    videoIsGenerating = true;
    try {
      let curMessage = "";
      const completion = await videoEngine.chat.completions.create({
        stream: true,
        messages
      });
      for await (const chunk of completion) {
        const curDelta = chunk.choices[0].delta.content;
        if (curDelta) {
          curMessage += curDelta;
        }
        onUpdate(curMessage);
      }
      const finalMessage = await videoEngine.getMessage();
      console.log(`Digital Human Video Generated final message: ${finalMessage}`); // Debugging
      onFinish(finalMessage);
      logMessage("Response generated successfully.", "system");
    } catch (err) {
      console.error(err);
      onError(err);
      logMessage("An error occurred during response generation.", "error");
    } finally {
      videoIsGenerating = false;
    }
  }

  // Flag to track the last input method
  let videoLastInputWasVoice = false;

  function videoAppendMessage(message) {
    console.log(`Digital Human Video Appending message: ${message.content} (Role: ${message.role})`); // Debugging
    const videoChatBox = document.getElementById("video-chat-box");

    // Check if the assistant's message is already appended to avoid duplication
    if (message.role === "assistant") {
      const existingMessages = videoChatBox.querySelectorAll(".message");
      const lastMessage = existingMessages[existingMessages.length - 1];
      if (lastMessage && lastMessage.textContent === message.content) {
        console.warn("Duplicate assistant message detected in Video section, skipping append.");

        // Only trigger TTS for assistant messages if the last input was via voice
        if (message.role === "assistant" && message.content !== "typing..." && videoLastInputWasVoice) {
          videoSpeak(message.content);
        }

        return; // Exit to avoid appending the same message twice
      }
    }

    const container = document.createElement("div");
    container.classList.add("message-container");
    const newMessage = document.createElement("div");
    newMessage.classList.add("message");
    newMessage.textContent = message.content;

    if (message.role === "user") {
      container.classList.add("user");
    } else {
      container.classList.add("assistant");
    }

    container.appendChild(newMessage);
    videoChatBox.appendChild(container);
    videoChatBox.scrollTop = videoChatBox.scrollHeight;

    // Only trigger TTS for assistant messages if the last input was via voice
    if (message.role === "assistant" && message.content !== "typing..." && videoLastInputWasVoice) {
      videoSpeak(message.content);
    }
  }

  function videoUpdateLastMessage(content) {
    const messageDoms = document.getElementById("video-chat-box").querySelectorAll(".message");
    const lastMessageDom = messageDoms[messageDoms.length - 1];
    lastMessageDom.textContent = content;
  }

  function videoOnSpeechRecognized(transcript) {
    const input = transcript.trim();
    const message = {
      content: input,
      role: "user"
    };
    if (input.length === 0) {
      return;
    }
    videoLastInputWasVoice = true; // Set flag as voice input
    console.log(`Digital Human Video Voice input received: ${input}`); // Debugging
    document.getElementById("video-start_button").disabled = true;
    document.getElementById("video-submit-button").disabled = true; // Disable submit button during processing

    videoMessages.push(message);
    videoAppendMessage(message);
    logMessage(`User (Voice): ${input}`, "user");

    // Append "typing..." placeholder
    const aiPlaceholder = {
      content: "typing...",
      role: "assistant"
    };
    videoAppendMessage(aiPlaceholder);
    logMessage("VideoBot is typing...", "system");

    const onFinishGenerating = (finalMessage) => {
      console.log(`Digital Human Video Finishing generation with message: ${finalMessage}`); // Debugging
      // Remove the "typing..." placeholder
      const videoChatBox = document.getElementById("video-chat-box");
      const lastMessageContainer = videoChatBox.lastElementChild;
      if (lastMessageContainer && lastMessageContainer.querySelector(".message").textContent === "typing...") {
        videoChatBox.removeChild(lastMessageContainer);
      }

      // Append the final message
      const aiMessage = {
        content: finalMessage,
        role: "assistant"
      };
      videoAppendMessage(aiMessage);
      logMessage(`VideoBot: ${finalMessage}`, "assistant");

      document.getElementById("video-start_button").disabled = false;
      document.getElementById("video-submit-button").disabled = false; // Re-enable submit button after processing
      videoEngine.runtimeStatsText().then((statsText) => {
        document.getElementById("video-chat-stats").classList.remove("hidden");
        document.getElementById("video-chat-stats").textContent = statsText;
        logMessage(`Runtime Stats: ${statsText}`, "system");
      });
    };

    videoStreamingGenerating(
      videoMessages,
      videoUpdateLastMessage,
      onFinishGenerating,
      (err) => {
        console.error(err);
        alert("An error occurred while generating the response. Please try again.");
        logMessage("Error during response generation.", "error");
        document.getElementById("video-start_button").disabled = false;
        document.getElementById("video-submit-button").disabled = false;
      }
    );
  }

  // Speech Recognition Code for Video
  let videoRecognizing = false;
  let videoIgnore_onend;
  let videoFinal_transcript = '';
  let videoRecognition;

  function videoStartButton(event) {
    if (videoRecognizing) {
      videoRecognition.stop();
      return;
    }
    videoFinal_transcript = '';
    videoRecognition.lang = 'en-US';
    videoRecognition.start();
    videoIgnore_onend = false;
    document.getElementById("video-start_button").classList.add("mic-animate");
    logMessage("Voice input started.", "system");
  }

  if (!('webkitSpeechRecognition' in window)) {
    alert("Web Speech API is not supported by this browser.");
    logMessage("Web Speech API is not supported by this browser.", "error");
  } else {
    videoRecognition = new webkitSpeechRecognition();
    videoRecognition.continuous = false; // Non-continuous recognition
    videoRecognition.interimResults = false; // Get only final results

    videoRecognition.onstart = function() {
      videoRecognizing = true;
      logMessage("Speech recognition started.", "system");
    };

    videoRecognition.onerror = function(event) {
      if (event.error == 'no-speech') {
        document.getElementById("video-start_button").classList.remove("mic-animate");
        alert('No speech was detected in Video section.');
        logMessage("No speech detected.", "error");
        videoIgnore_onend = true;
      }
      if (event.error == 'audio-capture') {
        document.getElementById("video-start_button").classList.remove("mic-animate");
        alert('No microphone was found in Video section.');
        logMessage("No microphone found.", "error");
        videoIgnore_onend = true;
      }
      if (event.error == 'not-allowed') {
        alert('Permission to use microphone was denied in Video section.');
        logMessage("Microphone permission denied.", "error");
        videoIgnore_onend = true;
      }
    };

    videoRecognition.onend = function() {
      videoRecognizing = false;
      document.getElementById("video-start_button").classList.remove("mic-animate");
      logMessage("Speech recognition ended.", "system");
      if (videoIgnore_onend) {
        return;
      }
      if (!videoFinal_transcript) {
        logMessage("No transcript captured.", "error");
        return;
      }
      // Process the final transcript
      videoOnSpeechRecognized(videoFinal_transcript);
    };

    videoRecognition.onresult = function(event) {
      for (let i = event.resultIndex; i < event.results.length; ++i) {
        if (event.results[i].isFinal) {
          videoFinal_transcript += event.results[i][0].transcript;
        }
      }
      videoFinal_transcript = videoFinal_transcript.trim();
      logMessage(`Recognized Speech: ${videoFinal_transcript}`, "user");
    };
  }

  document.getElementById("video-start_button").addEventListener("click", function(event) {
    videoStartButton(event);
  });

  // Initialize Model Selection
  videoAvailableModels.forEach((modelId) => {
    const option = document.createElement("option");
    option.value = modelId;
    option.textContent = modelId;
    document.getElementById("video-model-selection").appendChild(option);
  });
  document.getElementById("video-model-selection").value = videoSelectedModel;

  // **Enable the Download Model button after models are loaded**
  document.getElementById("video-download").disabled = false;

  document.getElementById("video-download").addEventListener("click", function () {
    videoInitializeWebLLMEngine().then(() => {
      document.getElementById("video-start_button").disabled = false;
      // Enable speech controls after model initialization
      document.getElementById("video-speech-rate").disabled = false;
      document.getElementById("video-speech-pitch").disabled = false;
      logMessage("Model download initiated.", "system");
    });
  });

  document.getElementById("video-clear-logs").addEventListener("click", function () {
    document.getElementById("video-logs").innerHTML = '';
    logMessage("Logs cleared.", "system");
  });

  // ===== TTS Integration =====

  // Initialize Speech Synthesis
  let videoSpeech = new SpeechSynthesisUtterance();
  videoSpeech.lang = "en";

  let videoVoices = [];

  // Use addEventListener instead of directly assigning to onvoiceschanged
  window.speechSynthesis.addEventListener("voiceschanged", () => {
    videoVoices = window.speechSynthesis.getVoices();
    videoPopulateVoices();
  });

  function videoPopulateVoices() {
    const voiceSelect = document.getElementById("video-tools");
    voiceSelect.innerHTML = ''; // Clear existing options
    videoVoices.forEach((voice, i) => {
      const option = new Option(voice.name, i);
      voiceSelect.appendChild(option);
    });
    if (videoVoices.length > 0) {
      const savedVoice = localStorage.getItem("video-selectedVoice");
      if (savedVoice !== null && videoVoices[savedVoice]) {
        videoSpeech.voice = videoVoices[savedVoice];
        voiceSelect.value = savedVoice;
      } else {
        videoSpeech.voice = videoVoices[0];
      }
    }
  }

  // Voice Selection Event Listener
  document.getElementById("video-tools").addEventListener("change", () => {
    const selectedVoiceIndex = document.getElementById("video-tools").value;
    videoSpeech.voice = videoVoices[selectedVoiceIndex];
    // Save to localStorage
    localStorage.setItem("video-selectedVoice", selectedVoiceIndex);
    logMessage(`Voice changed to: ${videoVoices[selectedVoiceIndex].name}`, "system");
  });

  // Function to Speak Text with Voice Selection and Handling Large Texts
  function videoSpeak(text) {
    if (!window.speechSynthesis) {
      console.warn("Speech Synthesis not supported in this browser for Video section.");
      logMessage("Speech Synthesis not supported in this browser.", "error");
      return;
    }

    // Show spinner and enable Stop button
    document.getElementById("video-loading-spinner").classList.remove("hidden");
    document.getElementById("video-stop_button").disabled = false;
    logMessage("TTS started.", "system");

    // Retrieve the currently selected voice
    const selectedVoice = videoSpeech.voice;

    // Split the text into sentences to manage large texts
    const sentences = text.match(/[^\.!\?]+[\.!\?]+/g) || [text];

    let utterancesCount = sentences.length;

    sentences.forEach(sentence => {
      const utterance = new SpeechSynthesisUtterance(sentence.trim());

      // Assign the selected voice to the utterance
      if (selectedVoice) {
        utterance.voice = selectedVoice;
      }

// Assign rate and pitch from sliders
      const rate = parseFloat(document.getElementById("video-speech-rate").value);
      const pitch = parseFloat(document.getElementById("video-speech-pitch").value);
      utterance.rate = rate; // Adjust the speaking rate (0.1 to 10)
      utterance.pitch = pitch; // Adjust the pitch (0 to 2)

      // Add event listeners for debugging or additional functionality
      utterance.onstart = () => {
        console.log("Speech started:", sentence);
        logMessage(`TTS started: ${sentence.trim()}`, "system");
      };

      utterance.onend = () => {
        console.log("Speech ended:", sentence);
        logMessage(`TTS ended: ${sentence.trim()}`, "system");
        utterancesCount--;
        if (utterancesCount === 0) {
          // Hide spinner and disable Stop button when all utterances have been spoken
          document.getElementById("video-loading-spinner").classList.add("hidden");
          document.getElementById("video-stop_button").disabled = true;
          logMessage("All TTS messages have been spoken.", "system");
        }
      };

      utterance.onerror = (e) => {
        console.error("Speech Synthesis Error:", e);
        alert("An error occurred during speech synthesis. Please try again.");
        logMessage("Speech synthesis encountered an error.", "error");
        utterancesCount = 0;
        document.getElementById("video-loading-spinner").classList.add("hidden");
        document.getElementById("video-stop_button").disabled = true;
      };

      window.speechSynthesis.speak(utterance);
    });
  }

  // ===== New: Stop Speech Functionality =====

  /**
   * Stops any ongoing speech synthesis.
   */
  function videoStopSpeech() {
    if (window.speechSynthesis.speaking) {
      window.speechSynthesis.cancel();
      document.getElementById("video-loading-spinner").classList.add("hidden");
      document.getElementById("video-stop_button").disabled = true;
      logMessage("Speech synthesis stopped by user.", "system");
    }
  }

  // Event Listener for Stop Button
  document.getElementById("video-stop_button").addEventListener("click", function () {
    videoStopSpeech();
  });

  // ===== New: Text Input Handling =====

  // Function to Handle Text Submission
  function videoHandleTextSubmit() {
    const textInput = document.getElementById("video-text-input");
    const input = textInput.value.trim();
    if (input.length === 0) {
      return;
    }
    textInput.value = ''; // Clear the input field
    const message = {
      content: input,
      role: "user" // Ensure this is correctly set
    };
    console.log(`Digital Human Video Text input received: ${input}`); // Debugging
    logMessage(`User: ${input}`, "user");

    videoLastInputWasVoice = false; // Set flag as text input
    document.getElementById("video-submit-button").disabled = true; // Disable to prevent multiple submissions

    videoMessages.push(message);
    videoAppendMessage(message);

    // Append "typing..." placeholder
    const aiPlaceholder = {
      content: "typing...",
      role: "assistant"
    };
    videoAppendMessage(aiPlaceholder);
    logMessage("VideoBot is typing...", "system");

    const onFinishGenerating = (finalMessage) => {
      console.log(`Digital Human Video Finishing generation with message: ${finalMessage}`); // Debugging
      // Remove the "typing..." placeholder
      const videoChatBox = document.getElementById("video-chat-box");
      const lastMessageContainer = videoChatBox.lastElementChild;
      if (lastMessageContainer && lastMessageContainer.querySelector(".message").textContent === "typing...") {
        videoChatBox.removeChild(lastMessageContainer);
      }

      // Append the final message
      const aiMessage = {
        content: finalMessage,
        role: "assistant"
      };
      videoAppendMessage(aiMessage);
      logMessage(`VideoBot: ${finalMessage}`, "assistant");

      // Trigger TTS for assistant messages if required
      if (videoLastInputWasVoice) {
        videoSpeak(finalMessage);
      }

      document.getElementById("video-submit-button").disabled = false; // Re-enable submit button after processing
      videoEngine.runtimeStatsText().then((statsText) => {
        document.getElementById("video-chat-stats").classList.remove("hidden");
        document.getElementById("video-chat-stats").textContent = statsText;
        logMessage(`Runtime Stats: ${statsText}`, "system");
      });
    };

    videoStreamingGenerating(
      videoMessages,
      videoUpdateLastMessage,
      onFinishGenerating,
      (err) => {
        console.error(err);
        alert("An error occurred while generating the response. Please try again.");
        logMessage("Error during response generation.", "error");
        document.getElementById("video-submit-button").disabled = false;
      }
    );
  }

  // Event Listener for Submit Button
  document.getElementById("video-submit-button").addEventListener("click", function () {
    videoHandleTextSubmit();
  });

  // Event Listener for Enter Key in Text Input
  document.getElementById("video-text-input").addEventListener("keypress", function (e) {
    if (e.key === 'Enter') {
      videoHandleTextSubmit();
    }
  });

  // ===== Persisting User Preferences =====

  // Load Preferences on Initialization
  window.addEventListener("load", () => {
    const savedVoice = localStorage.getItem("video-selectedVoice");
    if (savedVoice !== null && videoVoices[savedVoice]) {
      document.getElementById("video-tools").value = savedVoice;
      videoSpeech.voice = videoVoices[savedVoice];
      logMessage(`Loaded saved voice: ${videoVoices[savedVoice].name}`, "system");
    }

    const savedRate = localStorage.getItem("video-speechRate");
    if (savedRate !== null) {
      document.getElementById("video-speech-rate").value = savedRate;
      videoSpeech.rate = parseFloat(savedRate);
      logMessage(`Loaded saved speech rate: ${savedRate}`, "system");
    }

    const savedPitch = localStorage.getItem("video-speechPitch");
    if (savedPitch !== null) {
      document.getElementById("video-speech-pitch").value = savedPitch;
      videoSpeech.pitch = parseFloat(savedPitch);
      logMessage(`Loaded saved speech pitch: ${savedPitch}`, "system");
    }
  });

  // Save Speech Rate
  document.getElementById("video-speech-rate").addEventListener("input", (e) => {
    const rate = e.target.value;
    videoSpeech.rate = parseFloat(rate);
    localStorage.setItem("video-speechRate", rate);
    logMessage(`Speech rate changed to: ${rate}`, "system");
  });

  // Save Speech Pitch
  document.getElementById("video-speech-pitch").addEventListener("input", (e) => {
    const pitch = e.target.value;
    videoSpeech.pitch = parseFloat(pitch);
    localStorage.setItem("video-speechPitch", pitch);
    logMessage(`Speech pitch changed to: ${pitch}`, "system");
  });

  // ===== Logging Function =====

  /**
   * Logs messages to the #video-logs container.
   * @param {string} message - The message to log.
   * @param {string} type - The type of message: 'user', 'assistant', 'system', 'error'.
   */
  function logMessage(message, type) {
    const videoLogs = document.getElementById("video-logs");
    const logEntry = document.createElement("div");
    logEntry.classList.add("log-entry");
    logEntry.textContent = `[${type.toUpperCase()}] ${message}`;

    // Style log entries based on type
    switch(type) {
      case 'user':
        logEntry.style.color = "#00796B";
        break;
      case 'assistant':
        logEntry.style.color = "#004D40";
        break;
      case 'system':
        logEntry.style.color = "#555555";
        break;
      case 'error':
        logEntry.style.color = "#E53935";
        break;
      default:
        logEntry.style.color = "#000000";
    }

    videoLogs.appendChild(logEntry);
    videoLogs.scrollTop = videoLogs.scrollHeight;
  }

  // ===== TTS Integration Continued =====

  // Optional: Global Listener to Detect When All Speech Has Finished
  window.speechSynthesis.addEventListener('end', () => {
    console.log("All video speech has been spoken.");
    logMessage("All TTS messages have been spoken.", "system");
    // Ensure Stop button is disabled after speech ends
    document.getElementById("video-stop_button").disabled = true;
  });


  // Event Listener for Image Upload
  document.getElementById("video-image-upload").addEventListener("change", function (e) {
    const file = e.target.files[0];
    if (!file) {
      return;
    }

    const canvas = document.getElementById("video-image-canvas");
    const ctx = canvas.getContext("2d");
    const img = new Image();

    img.onload = function () {
      // Resize canvas to match image
      canvas.width = img.width;
      canvas.height = img.height;
      // Draw image on canvas
      ctx.drawImage(img, 0, 0);
      logMessage("Image uploaded and displayed on canvas.", "system");
    };

    img.onerror = function () {
      alert("Failed to load the image. Please try a different file.");
      logMessage("Failed to load the uploaded image.", "error");
    };

    // Read the image file as a Data URL
    const reader = new FileReader();
    reader.onload = function (event) {
      img.src = event.target.result;
    };
    reader.readAsDataURL(file);
  });

  // ===== Modified: Send Image to API via CORS Anywhere =====

  /**
   * Sends the base64-encoded image to the NVIDIA API through the CORS Anywhere proxy.
   * @param {string} imageB64 - The base64-encoded image string.
   * @param {function} onResult - Callback function to handle successful responses.
   * @param {function} onError - Callback function to handle errors.
   */
  function sendImageToAPI(imageB64, onResult, onError) {
    const proxyUrl = 'https://cors-anywhere.herokuapp.com/';
    const targetUrl = 'https://integrate.api.nvidia.com/v1/chat/completions';
    const invokeUrl = proxyUrl + targetUrl;
    const stream = false; // Streaming not supported via proxy

    const headers = {
      "Authorization": "Bearer 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",
      "Accept": "application/json",
      "Content-Type": "application/json"
    };

    const payload = {
      "model": "microsoft/phi-3.5-vision-instruct",
      "messages": [
        {
          "role": "user",
          "content": `Describe the image and solve it. <img src="data:image/jpeg;base64,${imageB64}" />`
        }
      ],
      "max_tokens": 512,
      "temperature": 0.20,
      "top_p": 0.70,
      "stream": stream
    };

    axios.post(invokeUrl, payload, { headers: headers })
      .then(response => {
        onResult(response.data);
      })
      .catch(error => {
        console.error(error);
        onError(error);
      });
  }

  // Event listener for Analyze button
  document.getElementById("analyze-button").addEventListener("click", function() {
    const canvas = document.getElementById("video-image-canvas");
    const imageDataURL = canvas.toDataURL("image/png");
    const imageB64 = imageDataURL.replace(/^data:image\/(png|jpg|jpeg);base64,/, "");

    const userMessage = {
      content: "Describe the image mathematically and solve it.",
      role: "user"
    };
    videoAppendMessage(userMessage);

    sendImageToAPI(imageB64, function(responseData) {
      const assistantMessage = {
        content: responseData.choices[0].message.content,
        role: "assistant"
      };
      videoAppendMessage(assistantMessage);
    }, function(error) {
      alert("Error: " + (error.response?.data?.error || error.message));
    });
  });

  // Event listener for Explain button (Webcam)
  document.getElementById("capture-webcam-button").addEventListener("click", function() {
    const video = document.getElementById("webcam-video");
    const canvas = document.getElementById("webcam-canvas");
    const context = canvas.getContext("2d");

    // Set canvas size to desired dimensions (e.g., 640x480)
    canvas.width = 640;
    canvas.height = 480;

    // Draw the video frame onto the canvas, scaling it to fit
    context.drawImage(video, 0, 0, canvas.width, canvas.height);

    const imageDataURL = canvas.toDataURL("image/jpeg", 0.8); // Use JPEG for smaller file size
    const imageB64 = imageDataURL.replace(/^data:image\/(png|jpg|jpeg);base64,/, "");

    const userMessage = {
      content: "Describe the image mathematically and solve it.",
      role: "user"
    };
    videoAppendMessage(userMessage);

    sendImageToAPI(imageB64, function(responseData) {
      const assistantMessage = {
        content: responseData.choices[0].message.content,
        role: "assistant"
      };
      videoAppendMessage(assistantMessage);
    }, function(error) {
      alert("Error: " + (error.response?.data?.error || error.message));
    });
  });

  // Event listener for Discuss button (Draw tab)
  document.getElementById("discuss-button").addEventListener("click", function() {
    const canvas = document.getElementById("draw-canvas");

    const ctx = canvas.getContext('2d');

    // Check if the canvas is empty
    const isCanvasBlank = ctx.getImageData(0, 0, canvas.width, canvas.height).data.every(channel => channel === 0);

    if (isCanvasBlank) {
      console.log("Canvas is blank. Please draw something before analyzing.");
      alert("The canvas is empty. Please draw something before analyzing.");
      return;
    }




    const imageDataURL = canvas.toDataURL("image/png");
    const imageB64 = imageDataURL.replace(/^data:image\/(png|jpg|jpeg);base64,/, "");

    console.log('Canvas dimensions:', canvas.width, 'x', canvas.height);
    console.log('Image data length:', imageB64.length);
    console.log('First 100 characters of image data:', imageB64.substring(0, 100));


    // Create a visual confirmation for the user
    //const confirmationImage = new Image();
    //confirmationImage.src = imageDataURL;
    //confirmationImage.onload = function() {
    //  const confirmationCanvas = document.createElement('canvas');
    //  confirmationCanvas.width = this.width;
    //  confirmationCanvas.height = this.height;
    //  const confirmCtx = confirmationCanvas.getContext('2d');
    //  confirmCtx.drawImage(this, 0, 0);

    //  document.body.appendChild(confirmationCanvas);
    //  setTimeout(() => document.body.removeChild(confirmationCanvas), 5000); // Remove after 5 seconds
    //};

    const userMessage = {
      content: "Describe the image mathematically and solve it.",
      role: "user"
    };
    videoAppendMessage(userMessage);

    sendImageToAPI(imageB64, function(responseData) {
      const assistantMessage = {
        content: responseData.choices[0].message.content,
        role: "assistant"
      };
      videoAppendMessage(assistantMessage);
    }, function(error) {
      alert("Error: " + (error.response?.data?.error || error.message));
    });
  });


  // Function to check if the canvas is blank
  function isCanvasBlank(canvas) {
    const context = canvas.getContext('2d');
    const pixelBuffer = new Uint32Array(
      context.getImageData(0, 0, canvas.width, canvas.height).data.buffer
    );
    return !pixelBuffer.some(color => color !== 0);
  }

  // Tab Switching Functionality
  const tabButtons = document.querySelectorAll('.image-tabs .tab-button');
  const tabContents = document.querySelectorAll('.video-image-section .tab-content');

  tabButtons.forEach(button => {
    button.addEventListener('click', () => {
      // Remove active class from all buttons
      tabButtons.forEach(btn => btn.classList.remove('active'));
      // Add active class to the clicked button
      button.classList.add('active');

      // Hide all tab contents
      tabContents.forEach(content => content.classList.add('hidden'));

// Show the selected tab content
      const selectedTab = button.getAttribute('data-tab');
      document.querySelector(`.video-image-section .${selectedTab}-tab`).classList.remove("hidden");

      // Initialize functionalities when their respective tabs are activated
      if (selectedTab === 'webcam') {
        initializeWebcam();
      }
      if (selectedTab === 'draw') {
        initializeDrawing();
      }
    });
  });

  // ------------------ Webcam Functionality ------------------

  let webcamStream = null;

  function initializeWebcam() {
    const video = document.getElementById('webcam-video');
    const captureButton = document.getElementById('capture-webcam-button');
    const canvas = document.getElementById('webcam-canvas');

    // Check if webcam is already initialized
    if (webcamStream) {
      return;
    }

    // Access the webcam
    navigator.mediaDevices.getUserMedia({ video: true })
      .then(stream => {
        webcamStream = stream;
        video.srcObject = stream;
        logMessage("Webcam access granted.", "system");
      })
      .catch(err => {
        console.error("Error accessing webcam:", err);
        alert("Unable to access the webcam. Please check permissions.");
        logMessage("Webcam access denied or error occurred.", "error");
      });

    // Capture Image from Webcam
    captureButton.addEventListener('click', () => {
      if (!webcamStream) {
        alert("Webcam not initialized.");
        return;
      }
      const context = canvas.getContext('2d');
      canvas.width = video.videoWidth;
      canvas.height = video.videoHeight;
      context.drawImage(video, 0, 0, canvas.width, canvas.height);
      logMessage("Webcam image captured.", "system");
    });
  }

  // Function to stop the webcam stream
  function stopWebcam() {
    if (webcamStream) {
      webcamStream.getTracks().forEach(track => track.stop());
      webcamStream = null;
      const videoElement = document.getElementById('webcam-video');
      if (videoElement) videoElement.srcObject = null;
      const canvas = document.getElementById('webcam-canvas');
      if (canvas && canvas.getContext) {
        const ctx = canvas.getContext('2d');
        ctx.clearRect(0, 0, canvas.width, canvas.height);
      }
      logMessage("Webcam stream stopped.", "system");
    }
  }

  // Modify the tab switching logic to include webcam cleanup
  tabButtons.forEach(button => {
    button.addEventListener('click', () => {
      // Existing tab switching code...
      // After switching tabs, check if the previous tab was Webcam and stop the stream
      const selectedTab = button.getAttribute('data-tab');
      if (selectedTab !== 'webcam') {
        stopWebcam();
      }
    });
  });

  // ------------------ Drawing Functionality ------------------

  let draw = false;
  let currentColor = '#000000';
  let currentSize = 2;
  let ctxDraw = null;
  let lastX = 0;
  let lastY = 0;

  function initializeDrawing() {
    const canvas = document.getElementById('draw-canvas');
    const colorPicker = document.getElementById('draw-color');
    const sizePicker = document.getElementById('draw-size');
    const clearButton = document.getElementById('clear-draw-button');

    if (ctxDraw) {
      return; // Drawing already initialized
    }

    ctxDraw = canvas.getContext('2d');
    canvas.width = canvas.offsetWidth;
    canvas.height = 400; // Fixed height

    //added by rahul
    canvas.style.backgroundColor = 'white';


    // Set initial styles
    ctxDraw.strokeStyle = currentColor;
    ctxDraw.lineWidth = currentSize;
    ctxDraw.lineJoin = 'round';
    ctxDraw.lineCap = 'round';

    //added by rahul
    ctxDraw.fillStyle ='white'
    ctxDraw.fillRect(0, 0, canvas.width, canvas.height);

    // Mouse Events
    canvas.addEventListener('mousedown', (e) => {
      draw = true;
      [lastX, lastY] = [e.offsetX, e.offsetY];
    });

    canvas.addEventListener('mousemove', drawLine);
    canvas.addEventListener('mouseup', () => draw = false);
    canvas.addEventListener('mouseout', () => draw = false);

    // Touch Events for mobile support
    canvas.addEventListener('touchstart', (e) => {
      e.preventDefault();
      if (e.touches.length === 1) {
        const touch = e.touches[0];
        const rect = canvas.getBoundingClientRect();
        lastX = touch.clientX - rect.left;
        lastY = touch.clientY - rect.top;
        draw = true;
      }
    });

    canvas.addEventListener('touchmove', (e) => {
      e.preventDefault();
      if (draw && e.touches.length === 1) {
        const touch = e.touches[0];
        const rect = canvas.getBoundingClientRect();
        const x = touch.clientX - rect.left;
        const y = touch.clientY - rect.top;
        drawLine({ offsetX: x, offsetY: y });
      }
    });

    canvas.addEventListener('touchend', () => draw = false);

    // Color Picker
    colorPicker.addEventListener('input', (e) => {
      currentColor = e.target.value;
      ctxDraw.strokeStyle = currentColor;
      logMessage(`Drawing color changed to: ${currentColor}`, "system");
    });

    // Size Picker
    sizePicker.addEventListener('input', (e) => {
      currentSize = e.target.value;
      ctxDraw.lineWidth = currentSize;
      logMessage(`Brush size changed to: ${currentSize}`, "system");
    });

    // Clear Drawing
    clearButton.addEventListener('click', () => {
      ctxDraw.clearRect(0, 0, canvas.width, canvas.height);
      logMessage("Drawing canvas cleared.", "system");
    });
  }

  function drawLine(e) {
    if (!draw) return;
    ctxDraw.beginPath();
    ctxDraw.moveTo(lastX, lastY);
    ctxDraw.lineTo(e.offsetX, e.offsetY);
    ctxDraw.stroke();
    [lastX, lastY] = [e.offsetX, e.offsetY];
  }

  // Adjust canvas size on window resize
  window.addEventListener('resize', () => {
    const drawCanvas = document.getElementById('draw-canvas');
    if (ctxDraw && drawCanvas.width !== drawCanvas.offsetWidth) {
      const imageData = ctxDraw.getImageData(0, 0, drawCanvas.width, drawCanvas.height);
      drawCanvas.width = drawCanvas.offsetWidth;
      ctxDraw.putImageData(imageData, 0, 0);
    }

    const webcamCanvas = document.getElementById('webcam-canvas');
    if (webcamCanvas) {
      webcamCanvas.width = webcamCanvas.offsetWidth;
      // Optionally, clear or redraw if necessary
    }
  });

  // ------------------ End of Additions ------------------

});