"""Tests for compile.py chunking + state-on-failure behavior.

Covers audit assertions #4 (failed SDK call doesn't mark log as compiled)
and the chunking correctness that underpins #5 (bounded prompt size).
"""

from __future__ import annotations

import asyncio
from pathlib import Path
from typing import Any
from unittest.mock import patch

import pytest

import compile as compile_mod


# ── Chunking correctness ────────────────────────────────────────────────

def test_chunk_small_log_single_chunk() -> None:
    small = "### Section A\nbody\n\n### Section B\nbody\n"
    chunks = compile_mod._split_log_into_chunks(small, max_chars=100_000)
    assert chunks == [small]


def test_chunk_reconstructs_byte_exact() -> None:
    sections = [f"### Section {i}\n" + "x" * 40_000 + "\n" for i in range(3)]
    large = "".join(sections)
    chunks = compile_mod._split_log_into_chunks(large, max_chars=100_000)
    assert "".join(chunks) == large


def test_chunk_respects_section_boundaries() -> None:
    # 4 sections of 30k each; max 70k → each chunk should be a clean
    # boundary cut, never splitting a `### ` header from its body.
    sections = [f"### S{i}\n" + "y" * 30_000 + "\n" for i in range(4)]
    large = "".join(sections)
    chunks = compile_mod._split_log_into_chunks(large, max_chars=70_000)
    # Every chunk that isn't the first should start with `### `.
    for chunk in chunks:
        if chunk != chunks[0]:
            assert chunk.startswith("### "), f"chunk boundary split mid-section: {chunk[:50]!r}"


def test_chunk_oversized_single_section_emits_alone() -> None:
    # Section larger than max_chars should be emitted as its own oversized
    # chunk rather than being split mid-thought.
    huge = "### One big section\n" + "z" * 150_000 + "\n"
    chunks = compile_mod._split_log_into_chunks(huge, max_chars=100_000)
    assert len(chunks) == 1
    assert chunks[0] == huge


def test_chunk_mixed_sizes() -> None:
    # Section headers must anchor at line-start (regex is `(?m)(?=^### )`),
    # so each section body must end with a newline.
    parts = [
        "### A\n" + "a" * 30_000 + "\n",
        "### B\n" + "b" * 30_000 + "\n",
        "### C\n" + "c" * 30_000 + "\n",
    ]
    content = "".join(parts)  # ~90K
    chunks = compile_mod._split_log_into_chunks(content, max_chars=80_000)
    # First chunk should contain A + B (~60K), second chunk C.
    assert len(chunks) == 2
    assert "### A" in chunks[0] and "### B" in chunks[0]
    assert "### C" in chunks[1]
    # Chunk 2 begins at a clean section boundary.
    assert chunks[1].startswith("### C")


# ── State-on-failure (acceptance #4) ────────────────────────────────────

@pytest.mark.asyncio
async def test_failed_sdk_does_not_mark_compiled(tmp_path: Path, monkeypatch) -> None:
    """If the SDK raises, compile_daily_log must NOT update state.json.

    Re-running should still see the log as uncompiled.
    """
    import config
    import utils

    # Redirect state file + paths to tmp.
    state_file = tmp_path / "state.json"
    daily_dir = tmp_path / "daily"
    daily_dir.mkdir()
    knowledge_dir = tmp_path / "knowledge"
    knowledge_dir.mkdir()

    monkeypatch.setattr(utils, "STATE_FILE", state_file)

    # Make a tiny fake daily log.
    log_path = daily_dir / "2026-04-24-test.md"
    log_path.write_text("### Test\nhello\n")

    # Make AGENTS.md resolvable (compile.py reads it).
    agents_file = tmp_path / "AGENTS.md"
    agents_file.write_text("# Test Schema\n")
    monkeypatch.setattr(config, "AGENTS_FILE", agents_file)
    monkeypatch.setattr(compile_mod, "AGENTS_FILE", agents_file)

    # Mock _invoke_llm to always fail.
    async def failing_invoke(_prompt: str) -> tuple[float, bool]:
        return (0.0, False)

    monkeypatch.setattr(compile_mod, "_invoke_llm", failing_invoke)

    state: dict[str, Any] = {"ingested": {}, "total_cost": 0.0}
    cost = await compile_mod.compile_daily_log(log_path, state)

    # Function returns 0.0 cost.
    assert cost == 0.0
    # State was NOT updated with this log's hash.
    assert log_path.name not in state.get("ingested", {})
    # state.json file was NOT written (save_state only runs on full success).
    assert not state_file.exists()


@pytest.mark.asyncio
async def test_partial_chunk_failure_does_not_mark_compiled(tmp_path: Path, monkeypatch) -> None:
    """Multi-chunk log: if chunk 2 fails, log must NOT be marked compiled.

    Verifies the `all_succeeded` gate holds across chunks.
    """
    import config
    import utils

    state_file = tmp_path / "state.json"
    daily_dir = tmp_path / "daily"
    daily_dir.mkdir()
    (tmp_path / "knowledge").mkdir()
    (tmp_path / "knowledge" / "index.md").write_text("(empty)")

    monkeypatch.setattr(utils, "STATE_FILE", state_file)

    # Log large enough to chunk (>100K) via 3 sections.
    sections = [f"### Section {i}\n" + "x" * 40_000 + "\n" for i in range(3)]
    log_path = daily_dir / "2026-04-24-big.md"
    log_path.write_text("".join(sections))

    agents_file = tmp_path / "AGENTS.md"
    agents_file.write_text("# Test Schema\n")
    monkeypatch.setattr(config, "AGENTS_FILE", agents_file)
    monkeypatch.setattr(compile_mod, "AGENTS_FILE", agents_file)

    # Patch read_wiki_index to return a dummy value (avoid hitting the real
    # knowledge dir).
    monkeypatch.setattr(compile_mod, "read_wiki_index", lambda: "(test index)")

    # _invoke_llm: succeed on 1st chunk, fail on 2nd. Track calls.
    calls = {"n": 0}

    async def flaky_invoke(_prompt: str) -> tuple[float, bool]:
        calls["n"] += 1
        if calls["n"] == 1:
            return (0.25, True)  # chunk 1 ok
        return (0.0, False)  # chunk 2 fails

    monkeypatch.setattr(compile_mod, "_invoke_llm", flaky_invoke)

    state: dict[str, Any] = {"ingested": {}, "total_cost": 0.0}
    cost = await compile_mod.compile_daily_log(log_path, state)

    # Returned partial cost (chunk 1 actually cost something).
    assert cost == 0.25
    # But state NOT updated — log is still "uncompiled" from the outside.
    assert log_path.name not in state.get("ingested", {})
    assert not state_file.exists()
    # Exactly 2 chunk attempts (first success, second failure, then bail).
    assert calls["n"] == 2


@pytest.mark.asyncio
async def test_all_chunks_succeed_updates_state(tmp_path: Path, monkeypatch) -> None:
    """When every chunk succeeds, state IS updated with the hash."""
    import config
    import utils

    state_file = tmp_path / "state.json"
    daily_dir = tmp_path / "daily"
    daily_dir.mkdir()
    (tmp_path / "knowledge").mkdir()

    monkeypatch.setattr(utils, "STATE_FILE", state_file)

    log_path = daily_dir / "2026-04-24-ok.md"
    log_path.write_text("### Section\nhi\n")

    agents_file = tmp_path / "AGENTS.md"
    agents_file.write_text("# Schema\n")
    monkeypatch.setattr(config, "AGENTS_FILE", agents_file)
    monkeypatch.setattr(compile_mod, "AGENTS_FILE", agents_file)
    monkeypatch.setattr(compile_mod, "read_wiki_index", lambda: "(index)")

    async def good_invoke(_prompt: str) -> tuple[float, bool]:
        return (0.10, True)

    monkeypatch.setattr(compile_mod, "_invoke_llm", good_invoke)

    state: dict[str, Any] = {"ingested": {}, "total_cost": 0.0}
    cost = await compile_mod.compile_daily_log(log_path, state)

    assert cost == 0.10
    assert log_path.name in state["ingested"]
    assert state["ingested"][log_path.name]["cost_usd"] == 0.10
    assert state["total_cost"] == 0.10
    # state.json now exists on disk.
    assert state_file.exists()