"""test_readonly.py — CRITICAL: ensure no write/ingest tools are exposed via MCP.

This test MUST fail if any write or ingest tool is accidentally registered.
It is the primary enforcement point for the read-only invariant of F-14.

Read-only tools (allowed):
  search, ask, wiki_read, wiki_list, discover_leads,
  provenance_verify, synthesis_browse

Write/ingest tools that must NEVER appear:
  Any tool whose name contains an ingest/write/delete/add/update/remove
  verb, or any of the known write-mode CLI operations.
"""

from __future__ import annotations

import asyncio
import re

# ---------------------------------------------------------------------------
# Write-verb pattern — any tool matching this is a forbidden write tool.
# ---------------------------------------------------------------------------

_WRITE_VERB_RE = re.compile(
    r"(?:^|_)(ingest|write|delete|remove|add|update|upsert|insert|create|sync|compile|export)",
    re.IGNORECASE,
)

# Explicit allowlist — only these names may appear.
ALLOWED_TOOLS = frozenset(
    {
        "search",
        "ask",
        "wiki_read",
        "wiki_list",
        "discover_leads",
        "provenance_verify",
        "synthesis_browse",
    }
)


def test_no_write_tools_registered() -> None:
    """CRITICAL: fail if any write-verb tool is registered on the MCP server."""
    from codex.mcp_server import mcp

    tools = asyncio.run(mcp.list_tools())
    registered = {t.name for t in tools}

    violations: list[str] = []
    for name in registered:
        if _WRITE_VERB_RE.search(name):
            violations.append(name)

    assert not violations, (
        f"Write/ingest tools found in MCP server (FORBIDDEN): {violations}. "
        "MCP server must expose read-only tools only."
    )


def test_only_allowed_tools_registered() -> None:
    """CRITICAL: registered tools must be a subset of the explicit allowlist."""
    from codex.mcp_server import mcp

    tools = asyncio.run(mcp.list_tools())
    registered = {t.name for t in tools}

    disallowed = registered - ALLOWED_TOOLS
    assert not disallowed, (
        f"Tools not on the read-only allowlist: {disallowed}. "
        "Add them to ALLOWED_TOOLS only after verifying they are read-only."
    )


def test_all_allowed_tools_present() -> None:
    """Every tool in the allowlist must be registered (completeness check)."""
    from codex.mcp_server import mcp

    tools = asyncio.run(mcp.list_tools())
    registered = {t.name for t in tools}

    missing = ALLOWED_TOOLS - registered
    assert not missing, f"Expected read-only tools missing from server: {missing}"