#!/usr/bin/env python3
# Copyright © Albert Lane. All Rights Reserved.
# Proprietary and Confidential — Albert Lane Proprietary Software License.
# Unauthorized use, copying, modification, or distribution is prohibited.
# License inquiries: https://albertlane.net
"""Build a LanePacket and get Albert's human signature onto it.

  make_packet.py build  spec.json out.bin        # spec: {"packet_id":1,"timestamp":...,"code":"MEM_WRITE","operands":[{"ref":7},{"int":42}],"payload_hex":""}
  make_packet.py digest packet.bin               # prints the exact text Albert signs with personal_sign (any Ethereum wallet)
  make_packet.py attach packet.bin SIGHEX out.bin  # attaches Albert's 65-byte signature as human_sig
"""
import json
import sys
import os

sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)), "..", "cosigner"))
import lane_digest as D  # noqa: E402
import lane_isa_pb2 as pb  # noqa: E402


def build(spec: dict) -> "pb.LanePacket":
    p = pb.LanePacket(packet_id=int(spec["packet_id"]), timestamp=int(spec["timestamp"]),
                      payload=bytes.fromhex(spec.get("payload_hex", "")))
    p.instr.code = pb.Instruction.OpCode.Value(spec["code"])
    for o in spec.get("operands", []):
        op = p.instr.operands.add()
        if "int" in o:
            op.type, op.i_val = pb.Operand.INT, int(o["int"])
        elif "float" in o:
            op.type, op.f_val = pb.Operand.FLOAT, float(o["float"])
        elif "str" in o:
            op.type, op.s_val = pb.Operand.STRING, str(o["str"])
        elif "ref" in o:
            op.type, op.ref_val = pb.Operand.REF, int(o["ref"])
        else:
            raise ValueError(f"bad operand {o}")
    return p


def human_digest(p) -> bytes:
    return D.h_human(p.packet_id, p.timestamp, D.instr_bytes(p.instr), p.payload)


def load(path):
    p = pb.LanePacket()
    p.ParseFromString(open(path, "rb").read())
    return p


if __name__ == "__main__":
    cmd = sys.argv[1] if len(sys.argv) > 1 else ""
    if cmd == "build":
        open(sys.argv[3], "wb").write(build(json.load(open(sys.argv[2]))).SerializeToString())
    elif cmd == "digest":
        print(human_digest(load(sys.argv[2])).hex())
    elif cmd == "attach":
        p = load(sys.argv[2])
        sig = bytes.fromhex(sys.argv[3].removeprefix("0x"))
        p.human_sig = sig
        print("signer:", D.recover(human_digest(p), sig))
        open(sys.argv[4], "wb").write(p.SerializeToString())
    else:
        print(__doc__)
        sys.exit(2)