"""Infra-overhead + thrash signal tests (WP-0005 T02)."""

import os
import sys

sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))

from session_memory.detect.signals import (  # noqa: E402
    build_context,
    extract_signals,
    sig_infra_overhead,
    sig_schema_thrash,
    sig_tool_thrash,
    tool_bucket,
)


def _digest(uid="claude:a", repo="r1", tools=None):
    return {"session_uid": uid, "flavor": "claude", "repo": repo, "outcome": "success",
            "cost": {"input_tokens": 1, "output_tokens": 1},
            "markers": {"errors": 0, "retries": 0, "test_runs": 0},
            "tool_histogram": tools or {}}


CTX = {"infra_min_calls": 20, "infra_overhead_threshold": 0.30,
       "schema_thrash_threshold": 5, "tool_thrash_threshold": 80}


def test_tool_bucket_mapping():
    assert tool_bucket("mcp__state-hub__update_task_status") == "statehub_mcp"
    assert tool_bucket("ToolSearch") == "schema_load"
    assert tool_bucket("TaskUpdate") == "task_mgmt"
    assert tool_bucket("Bash") == "shell"
    assert tool_bucket("Edit") == "edit"


def test_infra_overhead_fires_above_share():
    # 18 statehub of 30 total = 60% overhead
    d = _digest(tools={"mcp__state-hub__create_task": 18, "Bash": 8, "Edit": 4})
    sig = sig_infra_overhead(d, CTX)
    assert sig and sig[0].type == "infra_overhead"
    assert sig[0].magnitude >= 0.30
    assert sig[0].detail["statehub"] == 18


def test_infra_overhead_quiet_when_mostly_work():
    d = _digest(tools={"mcp__state-hub__create_task": 3, "Bash": 40, "Edit": 30})
    assert sig_infra_overhead(d, CTX) == []


def test_infra_overhead_ignores_tiny_sessions():
    d = _digest(tools={"mcp__state-hub__create_task": 5})  # below infra_min_calls
    assert sig_infra_overhead(d, CTX) == []


def test_schema_thrash_fires():
    d = _digest(tools={"ToolSearch": 9, "Bash": 5})
    sig = sig_schema_thrash(d, CTX)
    assert sig and sig[0].type == "schema_thrash"
    assert sig[0].detail["tool_searches"] == 9


def test_tool_thrash_fires_on_dominant_tool():
    d = _digest(tools={"Bash": 120, "Edit": 5})
    sig = sig_tool_thrash(d, CTX)
    assert sig and sig[0].locus == "tool:Bash"


def test_extract_signals_includes_infra():
    d = _digest(tools={"mcp__state-hub__create_task": 18, "Bash": 8, "Edit": 4,
                       "ToolSearch": 6})
    types = {s.type for s in extract_signals([d])}
    assert "infra_overhead" in types
    assert "schema_thrash" in types


def test_build_context_has_infra_defaults():
    ctx = build_context([])
    assert ctx["infra_overhead_threshold"] == 0.30
    assert ctx["schema_thrash_threshold"] == 5