"""Tests for prompt-only trajectory compaction."""

from swe_data_processing.evidence import (
    BOUNDARY_BLOCK_TURNS,
    build_trajectory_blocks,
    compact_text,
    compact_trajectory,
)


def test_compact_text_preserves_short_values() -> None:
    """Short evidence must remain byte-for-byte identical."""

    assert compact_text("short evidence", 100) == "short evidence"


def test_compact_text_hashes_long_values() -> None:
    """Long evidence must expose its size and digest for auditability."""

    result = compact_text("a" * 1_000, 200)
    assert len(result) == 200
    assert "COMPACTED original_chars=1000 sha256=" in result


def test_compact_trajectory_prioritizes_test_observations() -> None:
    """Important test output receives a larger preview than ordinary output."""

    long_content = "x" * 3_000
    trajectory = [
        {"turn_id": 1, "role": "user", "content": "issue"},
        {"turn_id": 2, "role": "assistant", "content": "", "tool_calls": []},
        {"turn_id": 3, "role": "tool", "content": long_content},
        {"turn_id": 4, "role": "assistant", "content": "done"},
    ]
    signals = {
        "stateful_turns": [],
        "test_events": [{"command_turn": 2, "output_turn": 3}],
        "malformed_tool_turns": [],
        "unknown_tool_turns": [],
    }
    compacted, metadata = compact_trajectory(trajectory, signals)
    assert compacted[2]["content"] == long_content
    assert 3 in metadata["important_turn_ids"]


def test_boundary_blocks_preserve_absolute_turns_without_overlap() -> None:
    trajectory = [
        {"turn_id": turn, "role": "assistant", "content": f"turn {turn}"}
        for turn in range(1, BOUNDARY_BLOCK_TURNS + 3)
    ]
    blocks, metadata = build_trajectory_blocks(trajectory, {})
    assert len(blocks) == 2
    assert blocks[0]["start_turn"] == 1
    assert blocks[0]["end_turn"] == BOUNDARY_BLOCK_TURNS
    assert blocks[1]["start_turn"] == BOUNDARY_BLOCK_TURNS + 1
    assert blocks[1]["end_turn"] == BOUNDARY_BLOCK_TURNS + 2
    turn_ids = [
        message["turn_id"] for block in blocks for message in block["messages"]
    ]
    assert turn_ids == list(range(1, BOUNDARY_BLOCK_TURNS + 3))
    assert metadata["block_count"] == 2


def test_boundary_block_keeps_immediate_tool_result_with_assistant() -> None:
    trajectory = [
        {"turn_id": turn, "role": "user", "content": f"turn {turn}"}
        for turn in range(1, BOUNDARY_BLOCK_TURNS + 2)
    ]
    trajectory[BOUNDARY_BLOCK_TURNS - 1]["role"] = "assistant"
    trajectory[BOUNDARY_BLOCK_TURNS]["role"] = "tool"
    blocks, _ = build_trajectory_blocks(trajectory, {})
    assert blocks[0]["end_turn"] == BOUNDARY_BLOCK_TURNS + 1
    assert len(blocks) == 1