import asyncio, json, urllib.request

async def recv_one(reader):
    b1 = await reader.readexactly(2)
    opcode = b1[0] & 0x0F
    masked_len = b1[1]
    length = masked_len & 0x7F
    if length == 126:
        length = int.from_bytes(await reader.readexactly(2), 'big')
    elif length == 127:
        length = int.from_bytes(await reader.readexactly(8), 'big')
    if masked_len & 0x80:
        mask = await reader.readexactly(4)
        payload = await reader.readexactly(length) if length else b''
        payload = bytes(b ^ mask[i % 4] for i, b in enumerate(payload))
    else:
        payload = await reader.readexactly(length) if length else b''
    return opcode, payload

async def send_text(writer, obj):
    data = json.dumps(obj).encode()
    mask = b'ABCD'
    frame = bytearray([0x81])
    n = len(data)
    if n < 126:
        frame.append(0x80 | n)
    elif n < (1<<16):
        frame.append(0x80 | 126); frame += n.to_bytes(2,'big')
    else:
        frame.append(0x80 | 127); frame += n.to_bytes(8,'big')
    frame += mask + bytes(b ^ mask[i % 4] for i,b in enumerate(data))
    writer.write(frame); await writer.drain()

async def main():
    ws = json.load(urllib.request.urlopen('http://127.0.0.1:9222/json/version'))['webSocketDebuggerUrl']
    hp = ws[len('ws://'):]
    hostport, _, path = hp.partition('/')
    host, port = hostport.split(':'); port = int(port); path='/' + path
    reader, writer = await asyncio.open_connection(host, port)
    req = f'GET {path} HTTP/1.1\r\nHost: {host}:{port}\r\nUpgrade: websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==\r\nSec-WebSocket-Version: 13\r\n\r\n'
    writer.write(req.encode()); await writer.drain(); await reader.readuntil(b'\r\n\r\n')
    next_id = 1
    async def call(method, params=None, sessionId=None):
        nonlocal next_id
        cid = next_id; next_id += 1
        msg = {'id': cid, 'method': method}
        if params is not None: msg['params'] = params
        if sessionId is not None: msg['sessionId'] = sessionId
        await send_text(writer, msg)
        while True:
            op, payload = await recv_one(reader)
            if op != 1: continue
            data = json.loads(payload.decode(errors='ignore'))
            if data.get('id') == cid:
                return data

    tid = (await call('Target.createTarget', {'url':'about:blank'}))['result']['targetId']
    sid = (await call('Target.attachToTarget', {'targetId': tid, 'flatten': True}))['result']['sessionId']
    await call('Page.enable', sessionId=sid)
    await call('Runtime.enable', sessionId=sid)
    await call('Page.navigate', {'url':'https://www.google.com/search?q=lightpanda'}, sessionId=sid)
    await asyncio.sleep(5)
    exprs = {
      'title': 'document.title',
      'url': 'location.href',
      'body': 'document.body ? document.body.innerText.slice(0,1500) : "NO_BODY"',
      'html': 'document.documentElement ? document.documentElement.outerHTML.slice(0,1500) : "NO_HTML"',
      'anchors': 'document.querySelectorAll("a").length'
    }
    for k,e in exprs.items():
        r = await call('Runtime.evaluate', {'expression': e, 'returnByValue': True}, sessionId=sid)
        print('@@'+k)
        print(r['result']['result'].get('value'))
    writer.close(); await writer.wait_closed()

asyncio.run(main())