wt32powermeter/javascript.h

const char JAVASCRIPT[] PROGMEM = R"=====(
<script>
var okaytogo = true;
var vu_meters_loaded = false;

// Function for drawing the LED bar graphs
function vumeter(elem, config){

    // Settings
    var max             = config.max || 100;
    var boxCount        = config.boxCount || 10;
    var boxCountRed     = config.boxCountRed || 2;
    var boxCountYellow  = config.boxCountYellow || 3;
    var boxGapFraction  = config.boxGapFraction || 0.2;
    var jitter          = 0;//config.jitter || 0.02;

    // Colours
    var redOn     = 'rgba(255,47,30,0.9)';
    var redOff    = 'rgba(64,12,8,0.9)';
    var yellowOn  = 'rgba(255,215,5,0.9)';
    var yellowOff = 'rgba(64,53,0,0.9)';
    var greenOn   = 'rgba(53,255,30,0.9)';
    var greenOff  = 'rgba(13,64,8,0.9)';

    // Derived and starting values
    var width = elem.width;
    var height = elem.height;
    var curVal = 0;

    // Gap between boxes and box height
    var boxHeight = height / (boxCount + (boxCount+1)*boxGapFraction);
    var boxGapY = boxHeight * boxGapFraction;

    var boxWidth = width - (boxGapY*2);
    var boxGapX = (width - boxWidth) / 2;

    // Canvas starting state
    var c = elem.getContext('2d');

    // Main draw loop
    var draw = function(){

        var targetVal = parseInt(elem.dataset.val, 10);

        // Gradual approach
        if (curVal <= targetVal){
            curVal += (targetVal - curVal) / 5;
        } else {
            curVal -= (curVal - targetVal) / 5;
        }
        curVal = targetVal;

        // Apply jitter
        if (jitter > 0 && curVal > 0){
            var amount = (Math.random()*jitter*max);
            if (Math.random() > 0.5){
                amount = -amount;
            }
            curVal += amount;
        }
        if (curVal < 0) {
            curVal = 0;
        }

        c.save();
        c.beginPath();
        c.rect(0, 0, width, height);
        c.fillStyle = 'rgb(32,32,32)';
        c.fill();
        c.restore();
        drawBoxes(c, curVal);

        requestAnimationFrame(draw);

    };

    // Draw the boxes
    function drawBoxes(c, val){
        c.save(); 
        c.translate(boxGapX, boxGapY);
        for (var i = 0; i < boxCount; i++){
            var id = getId(i);

            c.beginPath();
            if (isOn(id, val)){
                c.shadowBlur = 10;
                c.shadowColor = getBoxColor(id, val);
            }
            c.rect(0, 0, boxWidth, boxHeight);
            c.fillStyle = getBoxColor(id, val);
            c.fill();
            c.translate(0, boxHeight + boxGapY);
        }
        c.restore();
    }

    // Get the color of a box given it's ID and the current value
    function getBoxColor(id, val){
        // on colours
        if (id > boxCount - boxCountRed){
            return isOn(id, val)? redOn : redOff;
        }
        if (id > boxCount - boxCountRed - boxCountYellow){
            return isOn(id, val)? yellowOn : yellowOff;
        }
        return isOn(id, val)? greenOn : greenOff;
    }

    function getId(index){
        // The ids are flipped, so zero is at the top and
        // boxCount-1 is at the bottom. The values work
        // the other way around, so align them first to
        // make things easier to think about.
        return Math.abs(index - (boxCount - 1)) + 1;
    }

    function isOn(id, val){
        // We need to scale the input value (0-max)
        // so that it fits into the number of boxes
        var maxOn = Math.ceil((val/max) * boxCount);
        return (id <= maxOn);
    }

    draw();
}

setInterval(function() {
  // Call a function repetatively
  okaytogo = !okaytogo;
  getDATA();
}, 500);

function load_vu_meters() {
  vumeter(fwd_vu_meter, {
    "boxCount": 10,
    "boxGapFraction": 0.25,
    "max": strtoint(data[12]*1000000),
  });
  vumeter(ref_vu_meter, {
    "boxCount": 10,
    "boxGapFraction": 0.25,
    "max": strtoint(data[13]*1000000),
  });
  vumeter(swr_vu_meter, {
    "boxCount": 10,
    "boxGapFraction": 0.25,
    "max": strtoint((data[14]-1)*100),
  }); 
}

// plays a beep sound
function beep() {
    var snd = new Audio("data:audio/wav;base64,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
    snd.play();
}


// Converts a String to Integer
function strtoint(x) {
  const parsed = parseInt(x);
  if (isNaN(parsed)) { return 0; }
  return parsed;
}

// Formats a double/float to a String with n digits after the decimal point
function formatNum(num, separator, fraction) {
  var str = num.toLocaleString('en-US');
  str = str.replace(/\./, fraction);
  str = str.replace(/,/g, separator);
  str = str.substring(0, str.indexOf(fraction)+3);
  return str;
}


// Takes a number, returns a String with the number
// converted to uW, mW or Watt
function convert_power(val){
  let ret = "0";
    if (val == 0) {
      ret = "";
    } else if (val < 0.001){
      ret = formatNum(val*1000000,'','.') + " uW";
    } else if (val < 1) {
      ret = formatNum(val*1000,'','.') + " mW";
    } else {
      ret = formatNum(val*1.0,'','.') + " W";
    }
  return ret;
}

// returns a string of "--dBm" if the value is invalid
function check_dbm(val){
  let ret = "0";
  if (isNaN(val)) {
    ret = "-- dBm";
  } else if (val == "") {
    ret = "";
  } else {
    ret = val + " dBm";
  }
  return ret;
}


// gets data from backend and does a lot of stuff
function getDATA() {
  var xhttp = new XMLHttpRequest();
  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
      // Split the response string and create an array
      data = this.responseText.split(";");
      // display calculated power and dbm for FWD if voltage is between the lowest
      // and highest value of the translation table
      if (data[15] == "0") {
        document.getElementById("FWDWatt").innerHTML = convert_power(data[0]);
        document.getElementById("FWDdBm").innerHTML = check_dbm(data[1]);
        document.getElementById("FWDVoltage").innerHTML = data[2];
        // display LED bar graph for FWD if enabled via backend configuration
        if (data[17] == "true") {
          document.getElementById("fwd_led_box").style.display = 'inline-block';
          fwd_vu_meter.setAttribute('data-val', strtoint(data[0]*1000000));
        } else {
          document.getElementById("fwd_led_box").style.display = 'none';
        }
      } else { // voltage is out out bounds
        document.getElementById("FWDWatt").innerHTML = "---";
        document.getElementById("FWDdBm").innerHTML = "---";
        document.getElementById("FWDVoltage").innerHTML = data[2];
        // display LED bar graph for FWD if enabled via backend configuration
        // set value to 0
        if (data[17] == "true") {
          fwd_vu_meter.setAttribute('data-val', 0);
        } else {
          document.getElementById("fwd_led_box").style.display = 'none';
        }
      }
      // display calculated power and dbm for REF if voltage is between the lowest
      // and highest value of the translation table
      if (data[16] == "0") {
        document.getElementById("REFWatt").innerHTML = convert_power(data[3]);
        document.getElementById("REFdBm").innerHTML = check_dbm(data[4]);
        document.getElementById("REFVoltage").innerHTML = data[5];
        // display LED bar graph for REF if enabled via backend configuration
        if (data[18] == "true") {
          document.getElementById("ref_led_box").style.display = 'inline-block';
          ref_vu_meter.setAttribute('data-val', strtoint(data[3]*1000000));
        } else {
          document.getElementById("ref_led_box").style.display = 'none';
        }
      } else { // voltage is out out bounds
        document.getElementById("REFWatt").innerHTML = "---";
        document.getElementById("REFdBm").innerHTML = "---";
        document.getElementById("REFVoltage").innerHTML = data[5];
        // display LED bar graph for REF if enabled via backend configuration
        // set value to 0
        if (data[18] == "true") {
          ref_vu_meter.setAttribute('data-val', 0);
        } else {
          document.getElementById("ref_led_box").style.display = 'none';
        }
      }
      document.getElementById("VSWRValue").innerHTML = data[6];
      //document.getElementById("RLValue").innerHTML = data[7];
      document.getElementById("BANDValue").innerHTML = data[8]; // displays the chosen band
      document.getElementById("AntennaName").innerHTML = data[10]; // displays the name of the antenna
      document.getElementById("max_led_pwr_fwd").innerHTML = data[12]; // sets the FWD LED bar max value
      document.getElementById("max_led_pwr_ref").innerHTML = data[13]; // sets the REF LED bar max value
      document.getElementById("max_led_vswr").innerHTML = data[14]; // sets the VSWR LED bar max value
      document.getElementById("version").innerHTML = data[20]; // sets the version in the footer
      // displays "--" as VSWR if the value is too high or number is invalid
      if (data[6] == "-1" || data[6] == "inf" || data[15] == "1" || data[16] == "1") {
        document.getElementById("VSWRValue").innerHTML = "--";
        document.getElementById("RLValue").innerHTML = "--";
        document.getElementById("vswr_box").className = "box redbox";
      } else {
        // VSWR is ok
        document.getElementById("RLValue").innerHTML = data[7];
        document.getElementById("VSWRValue").innerHTML = data[6];
        // displays the VSWR box with red background if VSWR value is higher than the user configured limit
        if (parseFloat(data[6]) >= parseFloat(data[9]) || data[6] == "inf") {
          document.getElementById("vswr_box").className = "box redbox";
          // beeps if configured to do so
          if (data[11] == "true") {
            beep();
          }
        } else {
          // VSWR is fine, box is displayed with green background
          document.getElementById("vswr_box").className = "box";
        }
      }
      // displays FWD box with red background if value as been replaced with "--"
      if (data[0].startsWith('--') || data[1].startsWith('--')){
        document.getElementById("fwd_box").className = "box redbox";
      } else {
        document.getElementById("fwd_box").className = "box";
      }
      // displays REF box with red background if value as been replaced with "--"
      if (data[3].startsWith('--') || data[4].startsWith('--')){
        document.getElementById("ref_box").className = "box redbox";
      } else {
        document.getElementById("ref_box").className = "box";
      }
      // display VSWR bar graph if enabled via backend configuration
      if (data[19] == "true") {
        document.getElementById("vswr_led_box").style.display = 'inline-block';
        // if SWR value is invalid -> set to 0
        if (data[6] == "-1" || data[6] == "inf" || data[15] == "1" || data[16] == "1") {
          swr_vu_meter.setAttribute('data-val', 0);
        } else {
          swr_vu_meter.setAttribute('data-val', strtoint((data[6]-1)*100)); 
        }
      } else {
        document.getElementById("vswr_led_box").style.display = 'none';
      }
      if (!vu_meters_loaded){
        load_vu_meters();
        vu_meters_loaded = true;
      }
    }
  };
  xhttp.open("GET", "readDATA", true);
  xhttp.send();
}
</script>
)=====";