import sys
import json
import urllib.request

def upload(ip, script_id, code_file):
    # Read JS code
    with open(code_file, 'r', encoding='utf-8') as f:
        code = f.read()

    url = f"http://{ip}/rpc"

    # Stop the script first to prevent write locks
    print(f"Stopping script {script_id}...")
    req = urllib.request.Request(
        url,
        data=json.dumps({"id": 1, "method": "Script.Stop", "params": {"id": int(script_id)}}).encode('utf-8'),
        headers={'Content-Type': 'application/json'}
    )
    try:
        urllib.request.urlopen(req)
    except Exception as e:
        print(f"Stop request failed (might already be stopped): {e}")

    # Chunk the code into 500 byte chunks (Shelly RPC size limit)
    chunk_size = 500
    chunks = [code[i:i + chunk_size] for i in range(0, len(code), chunk_size)]

    for idx, chunk in enumerate(chunks):
        append = idx > 0
        print(f"Uploading chunk {idx + 1}/{len(chunks)} (append={append})...")
        payload = {
            "id": 1,
            "method": "Script.PutCode",
            "params": {
                "id": int(script_id),
                "code": chunk,
                "append": append
            }
        }
        req = urllib.request.Request(
            url,
            data=json.dumps(payload).encode('utf-8'),
            headers={'Content-Type': 'application/json'}
        )
        with urllib.request.urlopen(req) as resp:
            res = json.loads(resp.read().decode('utf-8'))
            if "error" in res:
                raise Exception(f"Failed to upload chunk: {res['error']}")
            
    print("Script upload complete!")

if __name__ == "__main__":
    if len(sys.argv) < 4:
        print("Usage: python3 upload.py <ip> <script_id> <code_file>")
        sys.exit(1)
    upload(sys.argv[1], sys.argv[2], sys.argv[3])