import * as Blockly from 'blockly';
import { pythonGenerator } from 'blockly/python';
import './blocks/esp32_blocks.js';
import './blocks/esp32_generators.js';
import { toolbox } from './blocks/toolbox.js';
import { connect, disconnect, isConnected, onData, writeString } from './serial/connection.js';
import { executeCode, stopExecution, saveToDevice } from './serial/repl.js';
import { flashFirmware } from './serial/flasher.js';
import { appendToTerminal, clearTerminal } from './ui/terminal.js';
import { initResizablePanels } from './ui/panels.js';
import './style.css';

// ─── Blockly Workspace ───────────────────────────────────

const workspace = Blockly.inject('blockly-div', {
  toolbox,
  theme: Blockly.Themes.Dark,
  grid: { spacing: 25, length: 3, colour: '#333', snap: true },
  zoom: { controls: true, wheel: true, startScale: 0.9, maxScale: 3, minScale: 0.3, scaleSpeed: 1.2 },
  trashcan: true,
  renderer: 'zelos',
});

// ─── Live Code Preview ───────────────────────────────────

const codeOutput = document.getElementById('code-output');

function updateCodePreview() {
  const code = pythonGenerator.workspaceToCode(workspace);
  codeOutput.textContent = code || '# Drag blocks to generate MicroPython code';
}

workspace.addChangeListener((event) => {
  if (event.isUiEvent) return;
  updateCodePreview();
});

updateCodePreview();

// ─── Workspace Persistence (localStorage) ────────────────

const STORAGE_KEY = 'esp32block_workspace';

function saveWorkspace() {
  const state = Blockly.serialization.workspaces.save(workspace);
  localStorage.setItem(STORAGE_KEY, JSON.stringify(state));
}

function loadWorkspace() {
  const json = localStorage.getItem(STORAGE_KEY);
  if (json) {
    try {
      const state = JSON.parse(json);
      Blockly.serialization.workspaces.load(state, workspace);
    } catch (_) {
      /* corrupted state, ignore */
    }
  }
}

workspace.addChangeListener((event) => {
  if (event.isUiEvent) return;
  saveWorkspace();
});

loadWorkspace();

// ─── Resize Handling ─────────────────────────────────────

function onResize() {
  const blocklyArea = document.getElementById('blockly-area');
  const blocklyDiv = document.getElementById('blockly-div');
  blocklyDiv.style.width = blocklyArea.offsetWidth + 'px';
  blocklyDiv.style.height = blocklyArea.offsetHeight + 'px';
  Blockly.svgResize(workspace);
}

window.addEventListener('resize', onResize);
onResize();
initResizablePanels();

// ─── UI State Helpers ────────────────────────────────────

const btnConnect = document.getElementById('btn-connect');
const btnFlash = document.getElementById('btn-flash');
const btnRun = document.getElementById('btn-run');
const btnStop = document.getElementById('btn-stop');
const btnSave = document.getElementById('btn-save');
const statusEl = document.getElementById('connection-status');
const terminalInput = document.getElementById('terminal-input');

function setConnectedUI(connected) {
  btnConnect.textContent = connected ? '⏏ Disconnect' : '▶ Connect';
  btnRun.disabled = !connected;
  btnStop.disabled = !connected;
  btnSave.disabled = !connected;
  terminalInput.disabled = !connected;
  statusEl.textContent = connected ? 'Connected' : 'Disconnected';
  statusEl.className = connected ? 'status-connected' : 'status-disconnected';
}

// ─── Serial Event Listeners ──────────────────────────────

onData((text) => appendToTerminal(text));

// ─── Toolbar Buttons ─────────────────────────────────────

btnConnect.addEventListener('click', async () => {
  try {
    if (isConnected()) {
      await disconnect();
      setConnectedUI(false);
      appendToTerminal('\n--- Disconnected ---\n');
    } else {
      await connect();
      setConnectedUI(true);
      appendToTerminal('--- Connected ---\n');
    }
  } catch (err) {
    appendToTerminal(`\nConnection error: ${err.message}\n`);
  }
});

const flashOverlay = document.getElementById('flash-overlay');
const flashLog = document.getElementById('flash-log');
const flashFill = document.getElementById('flash-progress-fill');
const flashPctText = document.getElementById('flash-progress-text');
const flashCloseBtn = document.getElementById('flash-close');

function showFlashOverlay() {
  flashLog.textContent = '';
  flashFill.style.width = '0%';
  flashPctText.textContent = '0%';
  flashCloseBtn.classList.add('hidden');
  flashOverlay.classList.remove('hidden');
}

function appendFlashLog(msg) {
  flashLog.textContent += msg;
  flashLog.scrollTop = flashLog.scrollHeight;
}

function setFlashProgress(pct) {
  flashFill.style.width = pct + '%';
  flashPctText.textContent = pct + '%';
}

flashCloseBtn.addEventListener('click', () => {
  flashOverlay.classList.add('hidden');
});

btnFlash.addEventListener('click', async () => {
  if (isConnected()) {
    await disconnect();
    setConnectedUI(false);
  }

  showFlashOverlay();

  try {
    await flashFirmware(
      (msg) => appendFlashLog(msg),
      (pct) => setFlashProgress(pct),
    );
    setFlashProgress(100);
    appendFlashLog('\nFlash complete! You can now Connect to use the device.\n');
  } catch (err) {
    appendFlashLog(`\nFlash error: ${err.message}\n`);
  } finally {
    flashCloseBtn.classList.remove('hidden');
  }
});

btnRun.addEventListener('click', async () => {
  const code = pythonGenerator.workspaceToCode(workspace);
  if (!code.trim()) {
    appendToTerminal('\nNo code to run. Add some blocks!\n');
    return;
  }
  appendToTerminal('\n>>> Running...\n');
  try {
    await executeCode(code);
  } catch (err) {
    appendToTerminal(`\nRun error: ${err.message}\n`);
  }
});

btnStop.addEventListener('click', async () => {
  try {
    await stopExecution();
    appendToTerminal('\n--- Stopped ---\n');
  } catch (err) {
    appendToTerminal(`\nStop error: ${err.message}\n`);
  }
});

btnSave.addEventListener('click', async () => {
  const code = pythonGenerator.workspaceToCode(workspace);
  if (!code.trim()) {
    appendToTerminal('\nNo code to save.\n');
    return;
  }
  appendToTerminal('\nSaving to device as main.py...\n');
  try {
    await saveToDevice(code);
  } catch (err) {
    appendToTerminal(`\nSave error: ${err.message}\n`);
  }
});

terminalInput.addEventListener('keydown', async (e) => {
  if (e.key === 'Enter') {
    const text = terminalInput.value;
    terminalInput.value = '';
    await writeString(text + '\r\n');
  }
});