import subprocess
from pathlib import Path

import pytest

from automation.config import RulesConfig
from automation.ai_config import DEFAULT_SENTINEL
from automation.patcher import ModelConfig, PatchGenerationError, generate_output


@pytest.fixture()
def temp_repo(tmp_path: Path) -> Path:
    repo = tmp_path / "repo"
    repo.mkdir()
    run(["git", "init"], cwd=repo)
    run(["git", "config", "user.email", "dev@example.com"], cwd=repo)
    run(["git", "config", "user.name", "Dev"], cwd=repo)
    return repo


def run(args: list[str], cwd: Path) -> None:
    subprocess.run(args, cwd=cwd, check=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)


def test_generate_output_creates_new_file(temp_repo: Path, tmp_path: Path) -> None:
    src = temp_repo / "Docs/features/FR_1/discussions/example.discussion.md"
    src.parent.mkdir(parents=True, exist_ok=True)
    src.write_text("- Alice: initial note\n", encoding="utf-8")
    run(["git", "add", src.relative_to(temp_repo).as_posix()], cwd=temp_repo)

    patch_text = """<<<AI_DIFF_START>>>
diff --git a/Docs/features/FR_1/discussions/example.discussion.sum.md b/Docs/features/FR_1/discussions/example.discussion.sum.md
--- /dev/null
+++ b/Docs/features/FR_1/discussions/example.discussion.sum.md
@@ -0,0 +1,2 @@
+Line one
+Line two
<<<AI_DIFF_END>>>
"""
    patch_file = tmp_path / "patch.txt"
    patch_file.write_text(patch_text, encoding="utf-8")

    model = ModelConfig(
        commands=[f"bash -lc 'cat {patch_file.as_posix()}'"],
        sentinel=DEFAULT_SENTINEL,
    )
    rules = RulesConfig(root=temp_repo, global_rules={"file_associations": {}, "rules": {}})

    generate_output(
        repo_root=temp_repo,
        rules=rules,
        model=model,
        source_rel=Path("Docs/features/FR_1/discussions/example.discussion.md"),
        output_rel=Path("Docs/features/FR_1/discussions/example.discussion.sum.md"),
        instruction="Generate summary",
    )

    output_file = temp_repo / "Docs/features/FR_1/discussions/example.discussion.sum.md"
    assert output_file.exists()
    assert output_file.read_text(encoding="utf-8") == "Line one\nLine two\n"

    staged = subprocess.run(
        ["git", "diff", "--cached", "--name-only"],
        cwd=temp_repo,
        check=True,
        capture_output=True,
        text=True,
    ).stdout.split()
    assert "Docs/features/FR_1/discussions/example.discussion.sum.md" in staged