'use strict';
(async () => {
// bind to the html
const uiBody = document.body;
const uiToggleThemeBtn = document.getElementById('theme-toggle');
const uiConnectWebUsbSerialBtn = document.getElementById('connect_webusb_serial_btn');
const uiConnectSerialBtn = document.getElementById('connect_serial_btn');
const uiDisconnectBtn = document.getElementById('disconnect_btn');
const uiNewlineModeSelect = document.getElementById('newline_mode_select');
const uiAutoReconnectCheckbox = document.getElementById('auto_reconnect_checkbox');
const uiForgetDeviceBtn = document.getElementById('forget_device_btn');
const uiForgetAllDevicesBtn = document.getElementById('forget_all_devices_btn');
const uiResetAllBtn = document.getElementById('reset_all_btn');
const uiCopyOutputBtn = document.getElementById('copy_output_btn');
const uiDownloadOutputCsvBtn = document.getElementById('download_csv_output_btn');
const uiStatusSpan = document.getElementById('status_span');
const uiCommandHistoryClearBtn = document.getElementById('clear_command_history_btn');
const uiCommandHistoryScrollbox = document.getElementById('command_history_scrollbox');
const uiCommandLineInput = document.getElementById('command_line_input');
const uiSendModeBtn = document.getElementById('send_mode_btn');
const uiReceivedDataClearBtn = document.getElementById('clear_received_data_btn');
const uiReceivedDataScrollbox = document.getElementById('received_data_scrollbox');
const uiNearTheBottomThreshold = 100; // pixels from the bottom to trigger scroll
const maxCommandHistoryLength = 123; // max number of command history entries
const maxReceivedDataLength = 8192 / 8; // max number of received data entries
const THEME_STATES = ['auto', 'light', 'dark'];
class CommandHistoryEntry {
constructor(text) {
this.text = text;
this.time = Date.now();
this.count = 1;
}
}
class ReceivedDataEntry {
constructor(text) {
this.text = text;
this.time = Date.now();
this.terminated = false;
}
}
class Application {
constructor() {
this.currentPort = null;
this.textEncoder = new TextEncoder();
this.textDecoder = new TextDecoder();
this.reconnectTimeoutId = null;
this.commandHistory = [];
this.uiCommandHistoryIndex = -1;
this.receivedData = [];
// bind the UI elements
uiToggleThemeBtn.addEventListener('click', () => this.toggleTheme());
// Listener for OS Theme Changes
window.matchMedia('(prefers-color-scheme: dark)').addEventListener('change', (e) => {
const currentPreference = localStorage.getItem('theme') || 'auto';
// Only act if the user is in automatic mode
if (currentPreference === 'auto') {
this.setTheme('auto');
}
});
uiConnectWebUsbSerialBtn.addEventListener('click', () => this.connectWebUsbSerialPort());
uiConnectSerialBtn.addEventListener('click', () => this.connectSerialPort());
uiDisconnectBtn.addEventListener('click', () => this.disconnectPort());
uiNewlineModeSelect.addEventListener('change', () => this.setNewlineMode());
uiAutoReconnectCheckbox.addEventListener('change', () => this.autoReconnectChanged());
uiForgetDeviceBtn.addEventListener('click', () => this.forgetPort());
uiForgetAllDevicesBtn.addEventListener('click', () => this.forgetAllPorts());
uiResetAllBtn.addEventListener('click', () => this.resetAll());
uiCopyOutputBtn.addEventListener('click', () => this.copyOutput());
uiDownloadOutputCsvBtn.addEventListener('click', () => this.downloadOutputCsv());
uiCommandHistoryClearBtn.addEventListener('click', () => this.clearCommandHistory());
uiCommandLineInput.addEventListener('keydown', (e) => this.handleCommandLineInput(e));
uiSendModeBtn.addEventListener('click', () => this.toggleSendMode());
uiReceivedDataClearBtn.addEventListener('click', () => this.clearReceivedData());
// restore state from localStorage
try {
this.restoreState();
} catch (error) {
console.error('Failed to restore state from localStorage', error);
this.resetAll();
this.restoreState();
}
this.updateUIConnectionState();
this.connectWebUsbSerialPort(true);
}
restoreState() {
// Restore theme choice
const savedTheme = localStorage.getItem('theme');
if (savedTheme) {
this.setTheme(savedTheme);
}
// Restore command history
let savedCommandHistory = JSON.parse(localStorage.getItem('commandHistory') || '[]');
for (const cmd of savedCommandHistory) {
this.appendCommandToHistory(cmd);
}
// Restore received data
let savedReceivedData = JSON.parse(localStorage.getItem('receivedData') || '[]');
for (let line of savedReceivedData) {
line.terminated = true;
this.appendReceivedData(line);
}
this.sendMode = localStorage.getItem('sendMode') || 'command';
this.setSendMode(this.sendMode);
uiAutoReconnectCheckbox.checked = !(localStorage.getItem('autoReconnect') === 'false');
let savedNewlineMode = localStorage.getItem('newlineMode');
if (savedNewlineMode) {
uiNewlineModeSelect.value = savedNewlineMode;
}
}
setTheme(theme) {
const modeName = theme.charAt(0).toUpperCase() + theme.slice(1);
uiToggleThemeBtn.textContent = `Theme: ${modeName}`;
if (theme === 'auto') {
// In auto mode, we rely on the OS preference.
// We check the media query and add/remove the class accordingly.
const prefersDark = window.matchMedia('(prefers-color-scheme: dark)').matches;
if (prefersDark) {
uiBody.classList.add('dark-mode');
} else {
uiBody.classList.remove('dark-mode');
}
} else if (theme === 'light') {
// Force light mode by removing the class.
uiBody.classList.remove('dark-mode');
} else if (theme === 'dark') {
// Force dark mode by adding the class.
uiBody.classList.add('dark-mode');
}
// Save the theme to localStorage
localStorage.setItem('theme', theme);
}
toggleTheme() {
const currentTheme = localStorage.getItem('theme') || 'auto';
const nextThemeIndex = (THEME_STATES.indexOf(currentTheme) + 1) % THEME_STATES.length;
const nextTheme = THEME_STATES[nextThemeIndex];
this.setTheme(nextTheme);
}
appendCommandToHistory(commandHistoryEntry) {
const wasNearBottom = uiCommandHistoryScrollbox.scrollHeight - uiCommandHistoryScrollbox.scrollTop <= uiCommandHistoryScrollbox.clientHeight + uiNearTheBottomThreshold;
let commandHistoryEntryBtn = null;
let lastCommandMatched = false;
if (this.commandHistory.length > 0) {
let lastCommandEntry = this.commandHistory[this.commandHistory.length - 1];
if (lastCommandEntry.text === commandHistoryEntry.text) {
lastCommandEntry.count++;
lastCommandEntry.time = Date.now();
lastCommandMatched = true;
// Update the last command entry
commandHistoryEntryBtn = uiCommandHistoryScrollbox.lastElementChild;
let time_str = new Date(lastCommandEntry.time).toLocaleString();
commandHistoryEntryBtn.querySelector('.command-history-entry-time').textContent = time_str;
commandHistoryEntryBtn.querySelector('.command-history-entry-text').textContent = lastCommandEntry.text;
commandHistoryEntryBtn.querySelector('.command-history-entry-count').textContent = '×' + lastCommandEntry.count;
}
}
if (!lastCommandMatched) {
this.commandHistory.push(commandHistoryEntry);
// Create a new command history entry
commandHistoryEntryBtn = document.createElement('button');
commandHistoryEntryBtn.className = 'command-history-entry';
commandHistoryEntryBtn.type = 'button';
let time_str = new Date(commandHistoryEntry.time).toLocaleString();
commandHistoryEntryBtn.innerHTML = `
${time_str}
${commandHistoryEntry.text}
×${commandHistoryEntry.count}
`;
commandHistoryEntryBtn.addEventListener('click', () => {
if (uiCommandLineInput.disabled) return;
uiCommandLineInput.value = commandHistoryEntry.text;
uiCommandLineInput.focus();
});
uiCommandHistoryScrollbox.appendChild(commandHistoryEntryBtn);
}
// Limit the command history length
while (this.commandHistory.length > maxCommandHistoryLength) {
this.commandHistory.shift();
uiCommandHistoryScrollbox.removeChild(uiCommandHistoryScrollbox.firstElementChild);
}
// Save the command history to localStorage
localStorage.setItem('commandHistory', JSON.stringify(this.commandHistory));
// Scroll to the new entry if near the bottom
if (wasNearBottom) {
requestAnimationFrame(() => {
uiCommandHistoryScrollbox.scrollTop = uiCommandHistoryScrollbox.scrollHeight;
});
}
}
clearCommandHistory() {
this.commandHistory = [];
uiCommandHistoryScrollbox.innerHTML = '';
localStorage.removeItem('commandHistory');
this.setStatus('Command history cleared', 'info');
}
appendReceivedData(receivedDataEntry) {
const wasNearBottom = uiReceivedDataScrollbox.scrollHeight - uiReceivedDataScrollbox.scrollTop <= uiReceivedDataScrollbox.clientHeight + uiNearTheBottomThreshold;
let newReceivedDataEntries = [];
let updateLastReceivedDataEntry = false;
if (this.receivedData.length <= 0) {
newReceivedDataEntries.push(receivedDataEntry);
} else {
let lastReceivedDataEntry = this.receivedData[this.receivedData.length - 1];
// Check if the last entry is terminated
if (lastReceivedDataEntry.terminated) {
newReceivedDataEntries.push(receivedDataEntry);
} else {
if (!lastReceivedDataEntry.terminated) {
updateLastReceivedDataEntry = true;
this.receivedData.pop();
receivedDataEntry.text = lastReceivedDataEntry.text + receivedDataEntry.text;
}
// split the text into lines
let lines = receivedDataEntry.text.split(/\r?\n/);
// check if the last line is terminated by checking if it ends with an empty string
let lastLineTerminated = lines[lines.length - 1] === '';
if (lastLineTerminated) {
lines.pop(); // remove the last empty line
}
// create new entries for each line
for (let i = 0; i < lines.length; i++) {
let line = lines[i];
let entry = new ReceivedDataEntry(line);
if (i === lines.length - 1) {
entry.terminated = lastLineTerminated;
} else {
entry.terminated = true;
}
newReceivedDataEntries.push(entry);
}
// if the last line is terminated, modify the last entry
if (lastLineTerminated) {
newReceivedDataEntries[newReceivedDataEntries.length - 1].terminated = true;
} else {
newReceivedDataEntries[newReceivedDataEntries.length - 1].terminated = false;
}
}
}
this.receivedData.push(...newReceivedDataEntries);
if (updateLastReceivedDataEntry) {
// update the rendering of the last entry
let lastReceivedDataEntryBtn = uiReceivedDataScrollbox.lastElementChild;
lastReceivedDataEntryBtn.querySelector('.received-data-entry-text').textContent = newReceivedDataEntries[0].text;
lastReceivedDataEntryBtn.querySelector('.received-data-entry-time').textContent = new Date(newReceivedDataEntries[0].time).toLocaleString();
newReceivedDataEntries.shift();
}
// render the new entries
let documentFragment = document.createDocumentFragment();
for (const entry of newReceivedDataEntries) {
let receivedDataEntryBtn = document.createElement('div');
receivedDataEntryBtn.className = 'received-data-entry';
receivedDataEntryBtn.innerHTML = `
${new Date(entry.time).toLocaleString()}
${entry.text}
`;
documentFragment.appendChild(receivedDataEntryBtn);
}
uiReceivedDataScrollbox.appendChild(documentFragment);
// Limit the received data length
while (this.receivedData.length > maxReceivedDataLength) {
this.receivedData.shift();
uiReceivedDataScrollbox.removeChild(uiReceivedDataScrollbox.firstElementChild);
}
// Save the received data to localStorage
localStorage.setItem('receivedData', JSON.stringify(this.receivedData));
// Scroll to the new entry if near the bottom
if (wasNearBottom) {
requestAnimationFrame(() => {
uiReceivedDataScrollbox.scrollTop = uiReceivedDataScrollbox.scrollHeight;
});
}
}
clearReceivedData() {
this.receivedData = [];
uiReceivedDataScrollbox.innerHTML = '';
localStorage.removeItem('receivedData');
this.setStatus('Received data cleared', 'info');
}
setStatus(msg, level = 'info') {
console.log(msg);
uiStatusSpan.textContent = msg;
uiStatusSpan.className = 'status status-' + level;
}
updateUIConnectionState() {
if (this.currentPort && this.currentPort.isConnected) {
uiConnectWebUsbSerialBtn.style.display = 'none';
uiConnectSerialBtn.style.display = 'none';
uiDisconnectBtn.style.display = 'block';
uiCommandLineInput.disabled = false;
uiCommandLineInput.focus();
} else {
if (serial.isWebUsbSupported()) {
uiConnectWebUsbSerialBtn.style.display = 'block';
}
if (serial.isWebSerialSupported()) {
uiConnectSerialBtn.style.display = 'block';
}
if (!serial.isWebUsbSupported() && !serial.isWebSerialSupported()) {
this.setStatus('Your browser does not support WebUSB or WebSerial', 'error');
}
uiDisconnectBtn.style.display = 'none';
uiCommandLineInput.disabled = true;
uiCommandLineInput.value = '';
uiCommandLineInput.blur();
}
}
async disconnectPort() {
this.stopAutoReconnect();
if (!this.currentPort) {
this.updateUIConnectionState();
return;
};
try {
await this.currentPort.disconnect();
this.setStatus('Disconnected', 'info');
}
catch (error) {
this.setStatus(`Disconnect error: ${error.message}`, 'error');
}
this.updateUIConnectionState();
}
async onReceive(dataView) {
this.updateUIConnectionState();
let text = this.textDecoder.decode(dataView);
let receivedDataEntry = new ReceivedDataEntry(text);
this.appendReceivedData(receivedDataEntry);
}
async onReceiveError(error) {
this.setStatus(`Read error: ${error.message}`, 'error');
await this.disconnectPort();
// Start auto reconnect on error if enabled
this.tryAutoReconnect();
}
async connectSerialPort() {
if (!serial.isWebSerialSupported()) {
this.setStatus('Serial not supported on this browser', 'error');
return;
}
try {
this.setStatus('Requesting device...', 'info');
this.currentPort = await serial.requestSerialPort();
this.currentPort.onReceiveError = error => this.onReceiveError(error);
this.currentPort.onReceive = dataView => this.onReceive(dataView);
await this.currentPort.connect();
this.setStatus('Connected', 'info');
} catch (error) {
this.setStatus(`Connection failed: ${error.message}`, 'error');
if (this.currentPort) {
await this.currentPort.forgetDevice();
this.currentPort = null;
}
}
}
async connectWebUsbSerialPort(initial = false) {
if (!serial.isWebUsbSupported()) {
this.setStatus('WebUSB not supported on this browser', 'error');
return;
}
try {
let first_time_connection = false;
let grantedDevices = await serial.getWebUsbSerialPorts();
if (initial) {
if (!uiAutoReconnectCheckbox.checked || grantedDevices.length === 0) {
return false;
}
// Connect to the device that was saved to localStorage otherwise use the first one
const savedPortInfo = JSON.parse(localStorage.getItem('webUSBSerialPort'));
if (savedPortInfo) {
for (const device of grantedDevices) {
if (device.device.vendorId === savedPortInfo.vendorId && device.device.productId === savedPortInfo.productId) {
this.currentPort = device;
break;
}
}
}
if (!this.currentPort) {
this.currentPort = grantedDevices[0];
}
this.setStatus('Connecting to first device...', 'info');
} else {
// Prompt the user to select a device
this.setStatus('Requesting device...', 'info');
this.currentPort = await serial.requestWebUsbSerialPort();
first_time_connection = true;
}
this.currentPort.onReceiveError = error => this.onReceiveError(error);
this.currentPort.onReceive = dataView => this.onReceive(dataView);
try {
await this.currentPort.connect();
// save the port to localStorage
const portInfo = {
vendorId: this.currentPort.device.vendorId,
productId: this.currentPort.device.productId,
}
localStorage.setItem('webUSBSerialPort', JSON.stringify(portInfo));
this.setStatus('Connected', 'info');
} catch (error) {
if (first_time_connection) {
// Forget the device if a first time connection fails
await this.currentPort.forgetDevice();
this.currentPort = null;
}
throw error;
}
this.updateUIConnectionState();
} catch (error) {
this.setStatus(`Connection failed: ${error.message}`, 'error');
}
}
async reconnectPort() {
if (this.currentPort) {
this.setStatus('Reconnecting...', 'info');
try {
await this.currentPort.connect();
this.setStatus('Reconnected', 'info');
} catch (error) {
this.setStatus(`Reconnect failed: ${error.message}`, 'error');
}
}
this.updateUIConnectionState();
}
async forgetPort() {
this.stopAutoReconnect();
if (this.currentPort) {
await this.currentPort.forgetDevice();
this.currentPort = null;
this.setStatus('Device forgotten', 'info');
} else {
this.setStatus('No device to forget', 'error');
}
this.updateUIConnectionState();
}
async forgetAllPorts() {
this.stopAutoReconnect();
await this.forgetPort();
if (serial.isWebUsbSupported()) {
let ports = await serial.getWebUsbSerialPorts();
for (const p of ports) {
await p.forgetDevice();
}
}
this.updateUIConnectionState();
}
setNewlineMode() {
localStorage.setItem('newlineMode', uiNewlineModeSelect.value);
}
autoReconnectChanged() {
if (uiAutoReconnectCheckbox.checked) {
this.setStatus('Auto-reconnect enabled', 'info');
this.tryAutoReconnect();
} else {
this.setStatus('Auto-reconnect disabled', 'info');
this.stopAutoReconnect();
}
localStorage.setItem('autoReconnect', uiAutoReconnectCheckbox.checked);
}
stopAutoReconnect() {
if (this.reconnectTimeoutId !== null) {
clearTimeout(this.reconnectTimeoutId);
this.reconnectTimeoutId = null;
this.setStatus('Auto-reconnect stopped.', 'info');
}
}
tryAutoReconnect() {
this.updateUIConnectionState();
if (!uiAutoReconnectCheckbox.checked) return;
if (this.reconnectTimeoutId !== null) return; // already trying
this.setStatus('Attempting to auto-reconnect...', 'info');
this.reconnectTimeoutId = setTimeout(async () => {
this.reconnectTimeoutId = null;
if (!uiAutoReconnectCheckbox.checked) {
this.setStatus('Auto-reconnect stopped.', 'info');
return;
}
if (this.currentPort) {
try {
await this.currentPort.connect();
} finally {
this.updateUIConnectionState();
}
}
}, 1000);
}
async handleCommandLineInput(e) {
// Instant mode: send key immediately including special keys like Backspace, arrows, enter, etc.
if (this.sendMode === 'instant') {
e.preventDefault();
// Ignore only pure modifier keys without text representation
if (e.key.length === 1 ||
e.key === 'Enter' ||
e.key === 'Backspace' ||
e.key === 'Tab' ||
e.key === 'Escape' ||
e.key === 'Delete' ) {
let sendText = '';
switch (e.key) {
case 'Enter':
switch (uiNewlineModeSelect.value) {
case 'CR': sendText = '\r'; break;
case 'CRLF': sendText = '\r\n'; break;
default: sendText = '\n'; break;
}
break;
case 'Backspace':
// Usually no straightforward char to send for Backspace,
// but often ASCII DEL '\x7F' or '\b' (0x08) is sent.
sendText = '\x08'; // backspace
break;
case 'Tab':
sendText = '\t';
break;
case 'Escape':
// Ignore or send ESC control char if needed
sendText = '\x1B';
break;
case 'Delete':
sendText = '\x7F'; // DEL char
break;
default:
sendText = e.key;
}
try {
await this.currentPort.send(this.textEncoder.encode(sendText));
} catch (error) {
this.setStatus(`Send error: ${error.message}`, 'error');
this.tryAutoReconnect();
}
}
return;
}
// Command mode: handle up/down arrow keys for history
if (e.key === 'ArrowUp' || e.key === 'ArrowDown') {
e.preventDefault();
if (this.commandHistory.length === 0) return;
if (e.key === 'ArrowUp') {
if (this.uiCommandHistoryIndex === -1) this.uiCommandHistoryIndex = this.commandHistory.length - 1;
else if (this.uiCommandHistoryIndex > 0) this.uiCommandHistoryIndex--;
} else if (e.key === 'ArrowDown') {
if (this.uiCommandHistoryIndex !== -1) this.uiCommandHistoryIndex++;
if (this.uiCommandHistoryIndex >= this.commandHistory.length) this.uiCommandHistoryIndex = -1;
}
uiCommandLineInput.value = this.uiCommandHistoryIndex === -1 ? '' : this.commandHistory[this.uiCommandHistoryIndex].text;
return;
}
if (e.key !== 'Enter' || !this.currentPort.isConnected) return;
e.preventDefault();
const text = uiCommandLineInput.value;
if (!text) return;
// Convert to Uint8Array with newline based on config
let sendText = text;
switch (uiNewlineModeSelect.value) {
case 'CR':
sendText += '\r';
break;
case 'CRLF':
sendText += '\r\n';
break;
case 'ANY':
sendText += '\n';
break;
}
const data = this.textEncoder.encode(sendText);
try {
await this.currentPort.send(data);
this.uiCommandHistoryIndex = -1;
let history_cmd_text = sendText.replace(/[\r\n]+$/, '');
let history_entry = new CommandHistoryEntry(history_cmd_text);
this.appendCommandToHistory(history_entry);
uiCommandLineInput.value = '';
} catch (error) {
this.setStatus(`Send error: ${error.message}`, 'error');
this.tryAutoReconnect();
}
}
toggleSendMode() {
if (this.sendMode === 'instant') {
this.setSendMode('command');
} else {
this.setSendMode('instant');
}
}
setSendMode(mode) {
this.sendMode = mode;
if (mode === 'instant') {
uiSendModeBtn.classList.remove('send-mode-command');
uiSendModeBtn.classList.add('send-mode-instant');
uiSendModeBtn.textContent = 'Instant mode';
} else {
uiSendModeBtn.classList.remove('send-mode-instant');
uiSendModeBtn.classList.add('send-mode-command');
uiSendModeBtn.textContent = 'Command mode';
}
localStorage.setItem('sendMode', this.sendMode);
}
copyOutput() {
let text = '';
for (const entry of this.receivedData) {
text += entry.text;
if (entry.terminated) {
text += '\n';
}
}
if (text) {
navigator.clipboard.writeText(text).then(() => {
this.setStatus('Output copied to clipboard', 'info');
}, () => {
this.setStatus('Failed to copy output', 'error');
});
} else {
this.setStatus('No output to copy', 'error');
}
}
downloadOutputCsv() {
// save ,
let csvContent = 'data:text/csv;charset=utf-8,';
for (const entry of this.receivedData) {
let line = new Date(entry.time).toISOString() + ',"' + entry.text.replace(/[\r\n]+$/, '') + '"';
csvContent += line + '\n';
}
const encodedUri = encodeURI(csvContent);
const link = document.createElement('a');
link.setAttribute('href', encodedUri);
const filename = new Date().toISOString() + '_tinyusb_received_serial_data.csv';
link.setAttribute('download', filename);
document.body.appendChild(link);
link.click();
document.body.removeChild(link);
}
async resetAll() {
await this.forgetAllPorts();
// Clear localStorage
for (const key in localStorage) {
localStorage.removeItem(key);
}
// reload the page
window.location.reload();
}
}
const app = new Application();
})()