#!/usr/bin/env python3
"""UserPromptSubmit hook — block prompts until AirContext config is valid.

When state.config_missing is true, refuse the prompt with a guidance message.
Otherwise, pass through silently.
"""
from __future__ import annotations
import json
import os
import sys
from pathlib import Path

_HERE = Path(__file__).resolve().parent
sys.path.insert(0, str(_HERE))

from core.config_loader import validate_config  # noqa: E402
from core.state import StateFile  # noqa: E402


def _project_root(payload: dict) -> Path:
    cwd = payload.get("cwd") or os.environ.get("CLAUDE_PROJECT_DIR") or os.getcwd()
    return Path(cwd)


def main() -> int:
    raw = sys.stdin.read() or "{}"
    try:
        payload = json.loads(raw)
    except json.JSONDecodeError:
        payload = {}

    project = _project_root(payload)
    air = project / "AirContext"

    # Project hasn't opted in — silently allow. Users opt in by running
    # `aircontext` (which installs templates) or `/aircontext-init`.
    if not air.exists():
        return 0

    config = air / "config.yaml"
    if not config.exists():
        # Opted in but template install never completed.
        msg = (
            "AirContext: AirContext/ directory exists but config.yaml is missing. "
            "Run `/aircontext-init` to reinstall templates, or remove the AirContext/ "
            "directory if you no longer want compaction in this project."
        )
        print(json.dumps({"decision": "block", "reason": msg}))
        return 0

    err = validate_config(config)
    if err:
        msg = (
            f"AirContext config is invalid: {err}\n"
            "Edit AirContext/config.yaml and resubmit."
        )
        print(json.dumps({"decision": "block", "reason": msg}))
        return 0

    # Healthy — clear stale flag and pass through.
    state = StateFile(air / "state.json")
    if state.read().get("config_missing"):
        state.update(config_missing=False)
    return 0


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