"""Tests for composer_replication.ingestion.trace_examples (Wave 19).

Pins the contract that:
  1. ClaudeCodeIngester output → claude_states_to_trace_examples → list[TraceExample]
  2. Tool errors in source JSONL (`is_error: true`) survive the ingester's
     [TOOL_RESULT (ERROR)] tag → are detected by the adapter → mark the
     subsequent assistant turn with tool_error
  3. The default error classifier categorizes common error kinds
  4. The output is a valid input to ComposerDataCollator with hint_generator
"""
from __future__ import annotations

from pathlib import Path

import pytest

from composer_replication.ingestion import (
    ClaudeCodeIngester,
    TOOL_ERROR_TAG,
    claude_states_to_trace_examples,
    default_classify_error,
)


HERE = Path(__file__).resolve().parent
FIXTURE_DIR = HERE.parent.parent.parent / "spikes" / "007-real-trace-ingestion" / "fixtures"
ERROR_FIXTURE = FIXTURE_DIR / "synthetic_session_with_error.jsonl"
OK_FIXTURE = FIXTURE_DIR / "synthetic_session.jsonl"


# ----------------------------------------------------------------------
# Error classifier
# ----------------------------------------------------------------------


def test_classify_file_not_found():
    assert default_classify_error(
        "Error: File does not exist: /etc/foo.yaml"
    ) == "file_not_found"
    assert default_classify_error(
        "no such file or directory: /tmp/x"
    ) == "file_not_found"


def test_classify_permission_denied():
    assert default_classify_error("Permission denied") == "permission_denied"


def test_classify_command_not_found():
    assert default_classify_error("bash: foo: command not found") == "command_not_found"


def test_classify_unknown_falls_back():
    assert default_classify_error("something weird went wrong") == "tool_error"


# ----------------------------------------------------------------------
# Adapter — happy path with error site
# ----------------------------------------------------------------------


def test_adapter_emits_one_example_per_state():
    ingester = ClaudeCodeIngester(skip_sidechain=True, strip_thinking=True)
    states = list(ingester.ingest(ERROR_FIXTURE))
    examples = claude_states_to_trace_examples(states)
    assert len(examples) == len(states)


def test_adapter_detects_tool_error_on_recovery_turn():
    """The assistant turn IMMEDIATELY AFTER a [TOOL_RESULT (ERROR)] user
    turn must be marked with tool_error. Earlier assistant turns (before
    any error) and assistant turns separated from the error by a
    successful tool result must NOT be marked."""
    ingester = ClaudeCodeIngester(skip_sidechain=True, strip_thinking=True)
    states = list(ingester.ingest(ERROR_FIXTURE))
    examples = claude_states_to_trace_examples(states)

    # Find the example with at least one error turn
    error_examples = [
        ex for ex in examples
        if any(t.get("tool_error") for t in ex["turns"])
    ]
    assert error_examples, (
        f"Expected ≥1 example with a tool_error turn; got {len(error_examples)}. "
        f"Per-example error turns: {[(ex['trace_id'], sum(1 for t in ex['turns'] if t.get('tool_error'))) for ex in examples]}"
    )

    # The error fixture has one error site; one of the late states should have exactly 1 error turn
    err_counts = [
        sum(1 for t in ex["turns"] if t.get("tool_error"))
        for ex in examples
    ]
    assert max(err_counts) == 1, (
        f"Expected exactly 1 error turn in some state; counts: {err_counts}"
    )


def test_adapter_classifies_file_not_found_in_fixture():
    ingester = ClaudeCodeIngester(skip_sidechain=True, strip_thinking=True)
    states = list(ingester.ingest(ERROR_FIXTURE))
    examples = claude_states_to_trace_examples(states)
    error_turns = [t for ex in examples for t in ex["turns"] if t.get("tool_error")]
    assert any(t["tool_error"] == "file_not_found" for t in error_turns), (
        f"Expected 'file_not_found' classification on the fixture's "
        f"non-existent-config error; got: "
        f"{[t['tool_error'] for t in error_turns]}"
    )


def test_adapter_no_errors_on_clean_fixture():
    """The original Spike 007 fixture has no is_error: true rows, so no
    error turns should be detected."""
    ingester = ClaudeCodeIngester(skip_sidechain=True, strip_thinking=True)
    states = list(ingester.ingest(OK_FIXTURE))
    examples = claude_states_to_trace_examples(states)
    err_turns = [t for ex in examples for t in ex["turns"] if t.get("tool_error")]
    assert not err_turns, (
        f"Clean fixture should have 0 error turns; got "
        f"{len(err_turns)}: {[t['tool_error'] for t in err_turns]}"
    )


def test_adapter_preserves_role_and_content():
    """Every output turn should have role + content from the input messages."""
    ingester = ClaudeCodeIngester(skip_sidechain=True, strip_thinking=True)
    states = list(ingester.ingest(ERROR_FIXTURE))
    examples = claude_states_to_trace_examples(states)
    for ex in examples:
        for turn in ex["turns"]:
            assert "role" in turn
            assert "content" in turn
            assert turn["role"] in ("system", "user", "assistant", "tool")


def test_adapter_custom_error_kind_fn():
    """User-provided error_kind_fn should override default classification."""
    ingester = ClaudeCodeIngester(skip_sidechain=True, strip_thinking=True)
    states = list(ingester.ingest(ERROR_FIXTURE))

    def custom_kind(content: str) -> str:
        return "custom_kind"

    examples = claude_states_to_trace_examples(states, error_kind_fn=custom_kind)
    error_turns = [t for ex in examples for t in ex["turns"] if t.get("tool_error")]
    assert all(t["tool_error"] == "custom_kind" for t in error_turns)


def test_adapter_threads_final_reward():
    ingester = ClaudeCodeIngester(skip_sidechain=True, strip_thinking=True)
    states = list(ingester.ingest(ERROR_FIXTURE))
    examples = claude_states_to_trace_examples(states, final_reward=0.5)
    assert all(ex["final_reward"] == 0.5 for ex in examples)


# ----------------------------------------------------------------------
# Tool error tag constant
# ----------------------------------------------------------------------


def test_tool_error_tag_matches_ingester_output():
    """The TOOL_ERROR_TAG constant must match what ClaudeCodeIngester
    actually writes for is_error: true records."""
    ingester = ClaudeCodeIngester(skip_sidechain=True, strip_thinking=True)
    states = list(ingester.ingest(ERROR_FIXTURE))
    # Find a user-message containing an error tool_result
    contents = [
        m.get("content", "")
        for s in states for m in s["messages"]
        if m.get("role") == "user"
    ]
    assert any(TOOL_ERROR_TAG in c for c in contents if isinstance(c, str)), (
        f"TOOL_ERROR_TAG {TOOL_ERROR_TAG!r} not found in any user content; "
        f"the constant has drifted from the ingester's output format."
    )


# ----------------------------------------------------------------------
# Empty input
# ----------------------------------------------------------------------


def test_adapter_empty_input():
    assert claude_states_to_trace_examples([]) == []


def test_adapter_state_with_no_messages():
    """A degenerate state with empty messages should be skipped silently."""
    examples = claude_states_to_trace_examples([{"state_id": "empty", "messages": []}])
    assert examples == []