flash hexdump for banglejs2

flashdump.js

function loadMenu() {

  var menuItems = {
    "Open Flash": () => openFlash(),
    "Open File": () => openFile(),
    "Create File": () => createFile(),
    "": {
      value: ""
    },
    "About": {
      value: "me"
    },
  };
  var menu = E.showMenu(menuItems);

}

function createFile() {
  E.showMessage("Not yet implemented", "TODO");
  setTimeout(loadMenu, 1000);
}

function openFile() {
  E.showMessage("Not yet implemented", "TODO");
  setTimeout(loadMenu, 1000);

}
var gOffset = 0;
var gPeekByte = peek8;

function redraw() {
  try {
    E.showMenu();
    g.clear();
    g.setFont("4x6:2");
  } catch (e) {
    console.error(e);
  }

  g.setColor('#000');
  var addr = Number(gOffset).toString(16);
  var zeropad = "0000000000".substr(0, 4 - addr.length);
  g.setColor('#fff');
  g.drawString("[0x" + zeropad + addr + "] flash", 0, 0);
  for (i = 0; i < 128; i += 8) {
    if (16 + (i / 8) > g.getHeight()) {
      break;
    }
    var line = "";
    for (var j = i; j < i + 8; j++) {
      var bv = gPeekByte(gOffset + j);
      var byte = Number(bv).toString(16).substring(0, 2);
      byte = bv < 17 ? "0" + byte : byte;
      line += ((j % 2) ? "" : " ") + byte;
    }
    g.setColor('#ff0');

    g.drawString(line.trim(), 0, 14 + ((i / 8) * 14));
  }
}

Bangle.on('drag', function(event) {
  if (Math.abs(event.dy) < 3) {
    if (event.y > g.getHeight() / 2) {
      event.dy = -1;
    } else {
      event.dy = 1;
    }
  }

  if (event.dy < 0) {
    gOffset += 8;
  } else {
    if (gOffset < 8) {
      gOffset = 0;
    } else {
      gOffset -= 8;
    }
  }

  redraw();
});


function openFlash() {
  gPeekByte = peek8;
  redraw();
}

loadMenu();