#!/usr/bin/env python3
"""Integrator: retain manifests in RE and select a validated source-bound baseline."""
import argparse
import hashlib
import json
from pathlib import Path
import sys

from campaign import Campaign, ControlError, atomic_json
from dashboard import gate_valid, replay_valid


def retain(root, source, kind):
    data = source.read_bytes()
    digest = hashlib.sha256(data).hexdigest()
    value = json.loads(data)
    relative = f"campaign/evidence/{digest}-{kind}.json"
    path = root / relative
    path.parent.mkdir(parents=True, exist_ok=True)
    try:
        with path.open("xb") as file:
            file.write(data)
    except FileExistsError:
        if path.read_bytes() != data:
            raise ValueError("retained artifact differs from its content-addressed name")
    return value, {"path": relative, "sha256": digest}


def select(root, gate_path, replay_path, next_action):
    campaign = Campaign(str(root.resolve()))
    # Check before copying. Evidence selection does not create or change contract acceptance.
    gate = json.loads(gate_path.read_bytes())
    gate_valid(gate, gate.get("source"))
    binary = Path(gate["binary"]["path"])
    if not binary.is_file() or hashlib.sha256(binary.read_bytes()).hexdigest() != gate["binary"]["sha256"]:
        raise ValueError("gate executable missing or hash mismatch")
    with campaign.lock():
        gate, pointer = retain(root, gate_path, "gate")
        current = {"schema": "sots-current/1", "source": gate["source"], "gate": pointer,
                   "replay": None, "next_action": next_action}
        if replay_path:
            replay = json.loads(replay_path.read_bytes())
            replay_valid(root, replay, current, gate)
            _, current["replay"] = retain(root, replay_path, "replay")
        atomic_json(root / "campaign/current.json", current)
    return current


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--state-root", required=True, type=Path)
    parser.add_argument("--gate", required=True, type=Path)
    parser.add_argument("--replay", type=Path)
    parser.add_argument("--next-action", required=True)
    args = parser.parse_args()
    try:
        selected = select(args.state_root.resolve(), args.gate.resolve(),
                          args.replay.resolve() if args.replay else None, args.next_action)
        print(json.dumps({"gate": selected["gate"], "replay": selected["replay"]}, indent=2))
    except (ControlError, ValueError, OSError, KeyError, TypeError) as exc:
        print(f"select_evidence: {exc}", file=sys.stderr)
        return 1
    return 0


if __name__ == "__main__":
    sys.exit(main())