"""Prompts must survive being moved out of Python unchanged.

The snapshots under tests/golden/prompts/ were captured from the module-level
constants before they became files. Any drift here means the model is being given
different instructions than the ones that were evaluated, which is the kind of
regression that shows up as subtly worse answers rather than as a failure.

Regenerate deliberately, never casually:

    python tests/test_prompts_golden.py --update
"""
from __future__ import annotations

import sys
from pathlib import Path

try:
    import pytest
except ModuleNotFoundError:  # capture mode runs without the dev extras installed
    pytest = None

ROOT = Path(__file__).resolve().parents[1]
GOLDEN = Path(__file__).parent / "golden" / "prompts"

sys.path.insert(0, str(ROOT))

# name -> (module, attribute). Kept explicit rather than discovered, so adding a
# prompt is a deliberate act that shows up in review.
PROMPTS: dict[str, tuple[str, str]] = {
    "chat/orchestrator": ("backend.services.chat", "ORCHESTRATOR_SYSTEM"),
    "chat/worker": ("backend.services.chat", "WORKER_SYSTEM"),
    "chat/editor": ("backend.services.chat", "EDITOR_SYSTEM"),
    "chat/fact_checker": ("backend.services.chat", "FACT_CHECKER_SYSTEM"),
    "chat/language_checker": ("backend.services.chat", "LANGUAGE_CHECKER_SYSTEM"),
    "chat/shadow_communicator": ("backend.services.chat", "_SHADOW_INSTRUCTION"),
    "chat/planner": ("backend.services.chat", "PLANNER_SYSTEM"),
    "chat/researcher": ("backend.services.chat", "RESEARCHER_SYSTEM"),
    "research/discover": ("backend.services.research.board", "_DISCOVER_SYSTEM"),
    "research/scout_query": ("backend.services.research.board", "_SCOUT_QUERY_SYSTEM"),
    "research/followup": ("backend.services.research.board", "_FOLLOWUP_SYSTEM"),
    "research/answer": ("backend.services.research.synthesis", "_ANSWER_SYSTEM"),
    "research/report": ("backend.services.research.synthesis", "_REPORT_SYSTEM"),
    "research/trip": ("backend.services.research.trip", "_TRIP_SYSTEM"),
    "research/trip_final": ("backend.services.research.trip", "_FINAL_INSTRUCTION"),
    "tools/reader": ("backend.services.llm_tools", "_READER_SYSTEM"),
}


def _resolve(module_name: str, attr: str) -> str:
    import importlib

    return getattr(importlib.import_module(module_name), attr)


def _capture() -> dict[str, str]:
    return {name: _resolve(mod, attr) for name, (mod, attr) in PROMPTS.items()}


@(pytest.mark.parametrize("name", sorted(PROMPTS)) if pytest else (lambda f: f))
def test_prompt_matches_golden(name: str) -> None:
    path = GOLDEN / f"{name}.txt"
    assert path.exists(), f"No golden snapshot for {name}; run with --update to create one."
    module, attr = PROMPTS[name]
    assert _resolve(module, attr) == path.read_text(encoding="utf-8"), (
        f"Prompt {name} differs from its golden snapshot. If the change is "
        f"intended, re-run with --update and review the diff."
    )


def main() -> int:
    if "--update" not in sys.argv:
        print(__doc__)
        return 1
    from dotenv import load_dotenv

    load_dotenv(ROOT / ".env")
    GOLDEN.mkdir(parents=True, exist_ok=True)
    for name, text in _capture().items():
        path = GOLDEN / f"{name}.txt"
        path.parent.mkdir(parents=True, exist_ok=True)
        path.write_text(text, encoding="utf-8")
        print(f"  wrote {path.relative_to(ROOT)} ({len(text)} chars)")
    return 0


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