let socket = null;
let isCapturing = false;
let mediaStream = null;
let audioContext = null;
let scriptProcessor = null;
let language = null;

let isPaused = false;

const mediaElements = document.querySelectorAll('video, audio');
mediaElements.forEach((mediaElement) => {
  mediaElement.addEventListener('play', handlePlaybackStateChange);
  mediaElement.addEventListener('pause', handlePlaybackStateChange);
});


function handlePlaybackStateChange(event) {
  isPaused = event.target.paused;
}

function generateUUID() {
  let dt = new Date().getTime();
  const uuid = 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
    const r = (dt + Math.random() * 16) % 16 | 0;
    dt = Math.floor(dt / 16);
    return (c === 'x' ? r : (r & 0x3 | 0x8)).toString(16);
  });
  return uuid;
}


/**
 * Resamples the audio data to a target sample rate of 16kHz.
 * @param {Array|ArrayBuffer|TypedArray} audioData - The input audio data.
 * @param {number} [origSampleRate=44100] - The original sample rate of the audio data.
 * @returns {Float32Array} The resampled audio data at 16kHz.
 */
function resampleTo16kHZ(audioData, origSampleRate = 44100) {
  // Convert the audio data to a Float32Array
  const data = new Float32Array(audioData);

  // Calculate the desired length of the resampled data
  const targetLength = Math.round(data.length * (16000 / origSampleRate));

  // Create a new Float32Array for the resampled data
  const resampledData = new Float32Array(targetLength);

  // Calculate the spring factor and initialize the first and last values
  const springFactor = (data.length - 1) / (targetLength - 1);
  resampledData[0] = data[0];
  resampledData[targetLength - 1] = data[data.length - 1];

  // Resample the audio data
  for (let i = 1; i < targetLength - 1; i++) {
    const index = i * springFactor;
    const leftIndex = Math.floor(index).toFixed();
    const rightIndex = Math.ceil(index).toFixed();
    const fraction = index - leftIndex;
    resampledData[i] = data[leftIndex] + (data[rightIndex] - data[leftIndex]) * fraction;
  }

  // Return the resampled data
  return resampledData;
}

function startRecording(data) {
    socket = new WebSocket(`ws://${data.host}:${data.port}/`);
    language = data.language;

    const uuid = generateUUID();
    socket.onopen = function(e) { 
      socket.send(
        JSON.stringify({
            uid: uuid,
            language: data.language,
            task: data.task,
            model: data.modelSize
        })
      );
    };

    let isServerReady = false;
    socket.onmessage = async (event) => {
      const data = JSON.parse(event.data);
      if (data["uid"] !== uuid)
        return;
      
      if (data["status"] === "WAIT"){
        await browser.runtime.sendMessage({ action: "showPopup", data: data["message"] })
        return;
      }
      
      if (!isServerReady && data["message"] === "SERVER_READY"){
        isServerReady = true;
        return;
      }

      if (language === null ){
        language = data["language"];
        await browser.runtime.sendMessage({ action: "updateSelectedLanguage", data: language })      
        return
      }

      if (data["message"] === "DISCONNECT"){
        await browser.runtime.sendMessage({ action: "toggleCaptureButtons", data: false })        
        return
      }

      await browser.runtime.sendMessage({ action: "transcript", data: event.data })
          .catch(function(error) {
            console.error("Error sending message:", error);
          });
    };

  // Access the audio stream from the current tab
  navigator.mediaDevices.getUserMedia({ audio: true })
    .then(function(stream) {
      // Create a new MediaRecorder instance
      const audioDataCache = [];
      audioContext = new AudioContext();
      mediaStream = audioContext.createMediaStreamSource(stream);
      recorder = audioContext.createScriptProcessor(4096, 1, 1);

      recorder.onaudioprocess = async (event) => {
        if (!audioContext || !isCapturing || !isServerReady || isPaused) return;

        const inputData = event.inputBuffer.getChannelData(0);
        const audioData16kHz = resampleTo16kHZ(inputData, audioContext.sampleRate);

        audioDataCache.push(inputData);
        
        socket.send(audioData16kHz);
      };

      // Prevent page mute
      mediaStream.connect(recorder);
      recorder.connect(audioContext.destination);
    })
}

var elem_container = null;
var elem_text = null;

var segments = [];
var text_segments = [];

function initPopupElement() {
  if (document.getElementById('popupElement')) {
    return;
  }

  const popupContainer = document.createElement('div');
  popupContainer.id = 'popupElement';
  popupContainer.style.cssText = 'position: fixed; top: 50%; left: 50%; transform: translate(-50%, -50%); background: white; color: black; padding: 16px; border-radius: 10px; box-shadow: 0px 0px 10px rgba(0, 0, 0, 0.5); display: none; text-align: center;';

  const popupText = document.createElement('span');
  popupText.textContent = 'Default Text';
  popupText.className = 'popupText';
  popupText.style.fontSize = '24px';
  popupContainer.appendChild(popupText);

  const buttonContainer = document.createElement('div');
  buttonContainer.style.marginTop = '8px';
  const closePopupButton = document.createElement('button');
  closePopupButton.textContent = 'Close';
  closePopupButton.style.backgroundColor = '#65428A';
  closePopupButton.style.color = 'white';
  closePopupButton.style.border = 'none';
  closePopupButton.style.padding = '8px 16px'; // Add padding for better click area
  closePopupButton.style.cursor = 'pointer';
  closePopupButton.addEventListener('click', async () => {
    popupContainer.style.display = 'none';
    await browser.runtime.sendMessage({ action: 'toggleCaptureButtons', data: false });
  });
  buttonContainer.appendChild(closePopupButton);
  popupContainer.appendChild(buttonContainer);

  document.body.appendChild(popupContainer);
}


function showPopup(customText) {
  const popup = document.getElementById('popupElement');
  const popupText = popup.querySelector('.popupText');

  if (popup && popupText) {
      popupText.textContent = customText || 'Default Text'; // Set default text if custom text is not provided
      popup.style.display = 'block';
  }
}


function init_element() {
    if (document.getElementById('transcription')) {
        return;
    }

    elem_container = document.createElement('div');
    elem_container.id = "transcription";
    elem_container.style.cssText = 'padding-top:16px;font-size:18px;line-height:18px;position:fixed;top:85%;left:50%;transform:translate(-50%,-50%);width:500px;height:90px;opacity:0.9;z-index:100;background:black;border-radius:10px;color:white;';

    for (var i = 0; i < 4; i++) {
        elem_text = document.createElement('span');
        elem_text.style.cssText = 'position: absolute;padding-left:16px;padding-right:16px;';
        elem_text.id = "t" + i;
        elem_container.appendChild(elem_text);

        if (i == 3) {
            elem_text.style.top = "-1000px"
        }
    }

    document.body.appendChild(elem_container);

    let x = 0;
    let y = 0;

    // Query the element
    const ele = elem_container;

    // Handle the mousedown event
    // that's triggered when user drags the element
    const mouseDownHandler = function (e) {
        // Get the current mouse position
        x = e.clientX;
        y = e.clientY;

        // Attach the listeners to `document`
        document.addEventListener('mousemove', mouseMoveHandler);
        document.addEventListener('mouseup', mouseUpHandler);
    };

    const mouseMoveHandler = function (e) {
        // How far the mouse has been moved
        const dx = e.clientX - x;
        const dy = e.clientY - y;

        // Set the position of element
        ele.style.top = `${ele.offsetTop + dy}px`;
        ele.style.left = `${ele.offsetLeft + dx}px`;

        // Reassign the position of mouse
        x = e.clientX;
        y = e.clientY;
    };

    const mouseUpHandler = function () {
        // Remove the handlers of `mousemove` and `mouseup`
        document.removeEventListener('mousemove', mouseMoveHandler);
        document.removeEventListener('mouseup', mouseUpHandler);
    };

    ele.addEventListener('mousedown', mouseDownHandler);
}

function getStyle(el,styleProp)
{
    var x = document.getElementById(el);
    if (x.currentStyle)
        var y = x.currentStyle[styleProp];
    else if (window.getComputedStyle)
        var y = document.defaultView.getComputedStyle(x,null).getPropertyValue(styleProp);
    return y;
}

function get_lines(elem, line_height) {
    var divHeight = elem.offsetHeight;
    var lines = divHeight / line_height;

    var original_text = elem.innerHTML;

    var words = original_text.split(' ');
    var segments = [];
    var current_lines = 1;
    var segment = '';
    var segment_len = 0;
    for (var i = 0; i < words.length; i++)
    {
        segment += words[i] + ' ';
        elem.innerHTML = segment;
        divHeight = elem.offsetHeight;

        if ((divHeight / line_height) > current_lines) {
            var line_segment = segment.substring(segment_len, segment.length - 1 - words[i].length - 1);
            segments.push(line_segment);
            segment_len += line_segment.length + 1;
            current_lines++;
        }
    }

    var line_segment = segment.substring(segment_len, segment.length - 1)
    segments.push(line_segment);

    elem.innerHTML = original_text;

    return segments;

}

function remove_element() {
    var elem = document.getElementById('transcription')
    for (var i = 0; i < 4; i++) {
        document.getElementById("t" + i).remove();
    }
    elem.remove()
}

browser.runtime.onMessage.addListener((request, sender, sendResponse) => {
  const { action, data } = request;
  if (action === "startCapture") {
      isCapturing = true;
      startRecording(data);
  } else if (action === "stopCapture") {
    
    isCapturing = false;
    if (socket) {
        socket.close();
        socket = null;
    }
    
    if (audioContext) {
        audioContext.close();
        audioContext = null;
        mediaStream = null;
        recorder = null;
    }

    remove_element();

  } else if (action === "showWaitPopup") {
    
    initPopupElement();

    showPopup(`Estimated wait time ~ ${Math.round(data)} minutes`);

  } else if (action === "show_transcript"){
    if (!isCapturing) return;
    init_element();    
    message = JSON.parse(data);
    message = message["segments"];
    
    var text = '';
    for (var i = 0; i < message.length; i++) {
        text += message[i].text + ' ';
    }
    text = text.replace(/(\r\n|\n|\r)/gm, "");
    
    var elem = document.getElementById('t3');
    elem.innerHTML = text;
  
    var line_height_style = getStyle('t3', 'line-height');
    var line_height = parseInt(line_height_style.substring(0, line_height_style.length - 2));
    var divHeight = elem.offsetHeight;
    var lines = divHeight / line_height;
  
    text_segments = [];
    text_segments = get_lines(elem, line_height);
    
    elem.innerHTML = '';
  
    if (text_segments.length > 2) {
        for (var i = 0; i < 3; i++) {
            document.getElementById('t' + i).innerHTML = text_segments[text_segments.length - 3 + i];
        }
    } else {
        for (var i = 0; i < 3; i++) {
            document.getElementById('t' + i).innerHTML = '';
        }
    }
  
    if (text_segments.length <= 2) {
        for (var i = 0; i < text_segments.length; i++) {
            document.getElementById('t' + i).innerHTML = text_segments[i];
        }
    } else {
        for (var i = 0; i < 3; i++) {
            document.getElementById('t' + i).innerHTML = text_segments[text_segments.length - 3 + i];
        }
    }
  
    for (var i = 1; i < 3; i++)
    {
        var parent_elem = document.getElementById('t' + (i - 1));
        var elem = document.getElementById('t' + i);
        elem.style.top = parent_elem.offsetHeight + parent_elem.offsetTop + 'px';
    }
  }
  sendResponse({});
});