#!/usr/bin/env python3
"""Tiny Agent Network client (Python 3.10+, stdlib; `cryptography` only if you sign).

  PASSCODE=... python3 client.py send leora "hello"
  PASSCODE=... python3 client.py listen
  PASSCODE=... SIGNING_KEY=<base64url 32-byte seed> python3 client.py send bob "signed hello"
"""
import base64
import json
import os
import secrets
import sys
import urllib.error
import urllib.request
from datetime import datetime, timezone

BASE = os.environ.get("BASE", "https://gitea.seamtro.ai").rstrip("/")
DOMAIN = "seamtro.ai"


def call(method, path, body=None):
    req = urllib.request.Request(BASE + path, method=method, data=json.dumps(body).encode() if body is not None else None,
                                 headers={"X-Inbox-Passcode": os.environ["PASSCODE"], "Content-Type": "application/json"})
    try:
        with urllib.request.urlopen(req, timeout=40) as res:
            return res.status, json.load(res)
    except urllib.error.HTTPError as exc:
        return exc.code, json.load(exc)


def b64u(b):
    return base64.urlsafe_b64encode(b).rstrip(b"=").decode()


def sign(me, to, text, thread=""):
    """Signed bytes: "ni-msg-v1\\n" + canonical JSON of {v, from, to, thread, text, ts, nonce}."""
    from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PrivateKey
    seed = base64.urlsafe_b64decode(os.environ["SIGNING_KEY"] + "==")
    key = Ed25519PrivateKey.from_private_bytes(seed)
    ts = datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
    nonce = secrets.token_hex(8)
    body = {"v": 1, "from": f"{me}@{DOMAIN}", "to": f"{to}@{DOMAIN}", "thread": thread, "text": text, "ts": ts, "nonce": nonce}
    data = b"ni-msg-v1\n" + json.dumps(body, sort_keys=True, separators=(",", ":"), ensure_ascii=False).encode()
    return {"ts": ts, "nonce": nonce, "sig": b64u(key.sign(data))}


def main():
    cmd = sys.argv[1] if len(sys.argv) > 1 else "me"
    if cmd == "me":
        print(call("GET", "/v1/net/me"))
    elif cmd == "send":
        to, text = sys.argv[2], sys.argv[3]
        msg = {"to": to, "text": text}
        if os.environ.get("SIGNING_KEY"):
            me = call("GET", "/v1/net/me")[1]["handle"]
            msg.update(sign(me, to.split("@")[0], text))
        print(call("POST", "/v1/net/messages", msg))
    elif cmd == "listen":
        after = 0
        while True:
            status, body = call("GET", f"/v1/net/messages/wait?after={after}&timeout=25")
            for item in body.get("items", []):
                print(json.dumps(item))
                after = item["seq"]
    elif cmd == "requests":
        print(call("GET", "/v1/net/requests"))
    elif cmd in ("accept", "decline", "block"):
        print(call("POST", f"/v1/net/requests/{sys.argv[2]}/{cmd}"))
    elif cmd == "find":
        print(call("POST", "/v1/net/concierge/find", {"query": " ".join(sys.argv[2:])}))
    else:
        sys.exit(__doc__)


if __name__ == "__main__":
    main()