import contextlib
import json
from pathlib import Path
from unittest.mock import patch

from mempalace.hooks_cli import (
    SAVE_INTERVAL,
    STOP_BLOCK_REASON,
    PRECOMPACT_BLOCK_REASON,
    _count_human_messages,
    _sanitize_session_id,
    hook_stop,
    hook_session_start,
    hook_precompact,
)


# --- _sanitize_session_id ---


def test_sanitize_normal_id():
    assert _sanitize_session_id("abc-123_XYZ") == "abc-123_XYZ"


def test_sanitize_strips_dangerous_chars():
    assert _sanitize_session_id("../../etc/passwd") == "etcpasswd"


def test_sanitize_empty_returns_unknown():
    assert _sanitize_session_id("") == "unknown"
    assert _sanitize_session_id("!!!") == "unknown"


# --- _count_human_messages ---


def _write_transcript(path: Path, entries: list[dict]):
    with open(path, "w", encoding="utf-8") as f:
        for entry in entries:
            f.write(json.dumps(entry) + "\n")


def test_count_human_messages_basic(tmp_path):
    transcript = tmp_path / "t.jsonl"
    _write_transcript(
        transcript,
        [
            {"message": {"role": "user", "content": "hello"}},
            {"message": {"role": "assistant", "content": "hi"}},
            {"message": {"role": "user", "content": "bye"}},
        ],
    )
    assert _count_human_messages(str(transcript)) == 2


def test_count_skips_command_messages(tmp_path):
    transcript = tmp_path / "t.jsonl"
    _write_transcript(
        transcript,
        [
            {"message": {"role": "user", "content": "<command-message>status</command-message>"}},
            {"message": {"role": "user", "content": "real question"}},
        ],
    )
    assert _count_human_messages(str(transcript)) == 1


def test_count_handles_list_content(tmp_path):
    transcript = tmp_path / "t.jsonl"
    _write_transcript(
        transcript,
        [
            {"message": {"role": "user", "content": [{"type": "text", "text": "hello"}]}},
            {
                "message": {
                    "role": "user",
                    "content": [{"type": "text", "text": "<command-message>x</command-message>"}],
                }
            },
        ],
    )
    assert _count_human_messages(str(transcript)) == 1


def test_count_missing_file():
    assert _count_human_messages("/nonexistent/path.jsonl") == 0


def test_count_empty_file(tmp_path):
    transcript = tmp_path / "t.jsonl"
    transcript.write_text("")
    assert _count_human_messages(str(transcript)) == 0


def test_count_malformed_json_lines(tmp_path):
    transcript = tmp_path / "t.jsonl"
    transcript.write_text('not json\n{"message": {"role": "user", "content": "ok"}}\n')
    assert _count_human_messages(str(transcript)) == 1


# --- hook_stop ---


def _capture_hook_output(hook_fn, data, harness="claude-code", state_dir=None):
    """Run a hook and capture its JSON stdout output."""
    import io

    buf = io.StringIO()
    patches = [patch("mempalace.hooks_cli._output", side_effect=lambda d: buf.write(json.dumps(d)))]
    if state_dir:
        patches.append(patch("mempalace.hooks_cli.STATE_DIR", state_dir))
    with contextlib.ExitStack() as stack:
        for p in patches:
            stack.enter_context(p)
        hook_fn(data, harness)
    return json.loads(buf.getvalue())


def test_stop_hook_passthrough_when_active(tmp_path):
    with patch("mempalace.hooks_cli.STATE_DIR", tmp_path):
        result = _capture_hook_output(
            hook_stop,
            {"session_id": "test", "stop_hook_active": True, "transcript_path": ""},
            state_dir=tmp_path,
        )
    assert result == {}


def test_stop_hook_passthrough_when_active_string(tmp_path):
    with patch("mempalace.hooks_cli.STATE_DIR", tmp_path):
        result = _capture_hook_output(
            hook_stop,
            {"session_id": "test", "stop_hook_active": "true", "transcript_path": ""},
            state_dir=tmp_path,
        )
    assert result == {}


def test_stop_hook_passthrough_below_interval(tmp_path):
    transcript = tmp_path / "t.jsonl"
    _write_transcript(
        transcript,
        [{"message": {"role": "user", "content": f"msg {i}"}} for i in range(SAVE_INTERVAL - 1)],
    )
    result = _capture_hook_output(
        hook_stop,
        {"session_id": "test", "stop_hook_active": False, "transcript_path": str(transcript)},
        state_dir=tmp_path,
    )
    assert result == {}


def test_stop_hook_blocks_at_interval(tmp_path):
    transcript = tmp_path / "t.jsonl"
    _write_transcript(
        transcript,
        [{"message": {"role": "user", "content": f"msg {i}"}} for i in range(SAVE_INTERVAL)],
    )
    result = _capture_hook_output(
        hook_stop,
        {"session_id": "test", "stop_hook_active": False, "transcript_path": str(transcript)},
        state_dir=tmp_path,
    )
    assert result["decision"] == "block"
    assert result["reason"] == STOP_BLOCK_REASON


def test_stop_hook_tracks_save_point(tmp_path):
    transcript = tmp_path / "t.jsonl"
    _write_transcript(
        transcript,
        [{"message": {"role": "user", "content": f"msg {i}"}} for i in range(SAVE_INTERVAL)],
    )
    data = {"session_id": "test", "stop_hook_active": False, "transcript_path": str(transcript)}

    # First call blocks
    result = _capture_hook_output(hook_stop, data, state_dir=tmp_path)
    assert result["decision"] == "block"

    # Second call with same count passes through (already saved)
    result = _capture_hook_output(hook_stop, data, state_dir=tmp_path)
    assert result == {}


# --- hook_session_start ---


def test_session_start_passes_through(tmp_path):
    result = _capture_hook_output(
        hook_session_start,
        {"session_id": "test"},
        state_dir=tmp_path,
    )
    assert result == {}


# --- hook_precompact ---


def test_precompact_always_blocks(tmp_path):
    result = _capture_hook_output(
        hook_precompact,
        {"session_id": "test"},
        state_dir=tmp_path,
    )
    assert result["decision"] == "block"
    assert result["reason"] == PRECOMPACT_BLOCK_REASON