"""Compaction rebuilds dynamic tool schemas (forever-session fix, #95681 arc).

Forever-sessions (Bot Mode, gateway channels) never restart; compaction is
the only boundary where the prompt cache is already broken, so it is the
one sanctioned point for a tool-snapshot rebuild. These tests pin:
- refresh_agent_mcp_tools(content_aware=True) swaps on CONTENT change under
  a stable name set (the dynamic-schema case its name-only diff missed)
- content_aware=False keeps the old no-churn behavior (MCP-reload callers)
- the compaction helper is wired into the commit path and never raises
"""
import os
import sys
import unittest
from unittest.mock import patch

sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))


class _Agent:
    quiet_mode = True
    enabled_toolsets = ["image_gen"]
    disabled_toolsets = None


def _defs(desc):
    return [{"type": "function", "function": {
        "name": "image_generate", "description": desc,
        "parameters": {"type": "object", "properties": {}},
    }}]


class TestContentAwareRefresh(unittest.TestCase):
    def _agent_with(self, desc):
        agent = _Agent()
        agent.tools = _defs(desc)
        agent.valid_tool_names = {"image_generate"}
        agent._tool_snapshot_generation = 0
        return agent

    def _refresh(self, agent, new_desc, **kw):
        from tools.mcp_tool import refresh_agent_mcp_tools

        with patch("model_tools.get_tool_definitions",
                   return_value=_defs(new_desc)), \
             patch("tools.mcp_tool._reinject_post_build_tools",
                   return_value=set()):
            return refresh_agent_mcp_tools(agent, **kw)

    def test_content_change_swaps_when_content_aware(self):
        agent = self._agent_with("old capabilities text")
        self._refresh(agent, "new capabilities text", content_aware=True)
        self.assertIn("new capabilities",
                      agent.tools[0]["function"]["description"])

    def test_content_change_ignored_when_name_only(self):
        """MCP-reload callers keep the historical no-churn contract."""
        agent = self._agent_with("old capabilities text")
        self._refresh(agent, "new capabilities text", content_aware=False)
        self.assertIn("old capabilities",
                      agent.tools[0]["function"]["description"])

    def test_identical_content_keeps_identity(self):
        agent = self._agent_with("same text")
        before = agent.tools
        self._refresh(agent, "same text", content_aware=True)
        self.assertIs(agent.tools, before)


class TestCompactionWiring(unittest.TestCase):
    def test_helper_delegates_content_aware(self):
        from agent.conversation_compression import _refresh_agent_tool_definitions

        agent = _Agent()
        with patch("tools.mcp_tool.refresh_agent_mcp_tools",
                   return_value={"newly_added"}) as m:
            changed = _refresh_agent_tool_definitions(agent)
        self.assertTrue(changed)
        m.assert_called_once_with(agent, content_aware=True)

    def test_commit_path_calls_helper_and_survives_failure(self):
        """The commit boundary invokes the refresh and a raising refresh
        must not break compaction (wrapped in try/except at the call site).
        Pin the call-site contract by source: the helper call sits between
        _invalidate_system_prompt and the always-rebuild of the prompt
        (post-#95681: the keep-prompt containment branch is gone — the
        rebuilt prompt is compared byte-for-byte and only object identity
        is preserved on equality)."""
        import inspect
        from agent import conversation_compression as cc

        src = inspect.getsource(cc)
        i_invalidate = src.find("agent._invalidate_system_prompt()")
        i_refresh = src.find("_refresh_agent_tool_definitions(agent)",
                             i_invalidate)
        i_rebuild = src.find("rebuilt_system_prompt = agent._build_system_prompt(",
                             i_refresh)
        self.assertGreater(i_refresh, i_invalidate,
                           "refresh must follow prompt invalidation")
        self.assertGreater(i_rebuild, i_refresh,
                           "refresh must precede the prompt rebuild")
        guard_window = src[i_refresh - 400:i_refresh]
        self.assertIn("try:", guard_window,
                      "refresh call must be exception-guarded")


if __name__ == "__main__":
    unittest.main()