#!/usr/bin/env python3
"""
harness-state skill script.
Operations: get_state, set_state
State is stored in .codex-plugin/harness_state.json relative to the repo root.
Falls back to the current working directory if the .codex-plugin dir is not found.
"""

import json
import os
import sys
from pathlib import Path


STATE_FILENAME = "harness_state.json"

DEFAULT_STATE = {
    "active": False,
    "phase": 0,
    "phase_name": "",
}


def find_state_dir() -> Path:
    """Walk up from cwd looking for .codex-plugin/. Fall back to cwd."""
    cwd = Path.cwd()
    for parent in [cwd, *cwd.parents]:
        candidate = parent / ".codex-plugin"
        if candidate.is_dir():
            return candidate
    # Fallback: use cwd itself
    return cwd


def state_path() -> Path:
    return find_state_dir() / STATE_FILENAME


def read_state() -> dict:
    path = state_path()
    if not path.exists():
        return dict(DEFAULT_STATE)
    try:
        with open(path) as f:
            data = json.load(f)
        # Fill missing keys with defaults
        return {**DEFAULT_STATE, **data}
    except (json.JSONDecodeError, OSError):
        return dict(DEFAULT_STATE)


def write_state(active: bool, phase: int, phase_name: str) -> dict:
    state = {"active": active, "phase": phase, "phase_name": phase_name}
    path = state_path()
    path.parent.mkdir(parents=True, exist_ok=True)
    with open(path, "w") as f:
        json.dump(state, f, indent=2)
    return state


def main():
    if len(sys.argv) < 2:
        print(json.dumps({"error": "Usage: state.py <json_input>"}))
        sys.exit(1)

    try:
        args = json.loads(sys.argv[1])
    except json.JSONDecodeError as e:
        print(json.dumps({"error": f"Invalid JSON input: {e}"}))
        sys.exit(1)

    operation = args.get("operation")

    if operation == "get_state":
        result = read_state()
        print(json.dumps(result))

    elif operation == "set_state":
        active = args.get("active")
        phase = args.get("phase")
        phase_name = args.get("phase_name", "")

        if active is None or phase is None:
            print(json.dumps({"error": "set_state requires 'active' (bool) and 'phase' (int)"}))
            sys.exit(1)

        if not isinstance(active, bool):
            print(json.dumps({"error": "'active' must be a boolean"}))
            sys.exit(1)

        if not isinstance(phase, int):
            print(json.dumps({"error": "'phase' must be an integer"}))
            sys.exit(1)

        result = write_state(active=active, phase=phase, phase_name=str(phase_name))
        print(json.dumps({"ok": True, "state": result}))

    else:
        print(json.dumps({"error": f"Unknown operation '{operation}'. Valid: get_state, set_state"}))
        sys.exit(1)


if __name__ == "__main__":
    main()