"""A step that could not do its job says so with its exit code.

validate_pr --changed answered "No changed BIOS files detected" and exited
0 when git itself had failed (no origin, or no repository), and
check_buildbot_system --update exited 0 after a refresh it launched had
failed, the cache left at the old version.
"""

from __future__ import annotations

import json
import os
import shutil
import subprocess
import sys
import tempfile
import unittest
from pathlib import Path
from unittest import mock

REPO_ROOT = Path(__file__).resolve().parent.parent
sys.path.insert(0, str(REPO_ROOT / "scripts"))

import check_buildbot_system  # noqa: E402


class GitThatCannotAnswer(unittest.TestCase):
    def test_outside_a_repository_is_an_error_not_an_empty_change(self):
        with tempfile.TemporaryDirectory() as tmp:
            # TMPDIR may lie inside this repository (the audit gate puts it in
            # tmp/): git must not find the enclosing work tree from there.
            env = dict(os.environ, GIT_CEILING_DIRECTORIES=str(Path(tmp).parent))
            proc = subprocess.run(
                [sys.executable, str(REPO_ROOT / "scripts" / "validate_pr.py"), "--changed"],
                cwd=tmp, env=env, capture_output=True, text=True, timeout=60, check=False,
            )
        self.assertEqual(proc.returncode, 2, proc.stdout + proc.stderr)
        self.assertNotIn("No changed BIOS files detected", proc.stdout)

    def test_a_clone_without_origin_reads_the_index_and_says_so(self):
        with tempfile.TemporaryDirectory() as tmp:
            subprocess.run(["git", "init", "-q", tmp], check=True)
            Path(tmp, "bios").mkdir()
            Path(tmp, "bios", "x.bin").write_bytes(b"x")
            subprocess.run(["git", "-C", tmp, "add", "bios/x.bin"], check=True)
            proc = subprocess.run(
                [sys.executable, "-c", (
                    f"import sys; sys.path.insert(0, {str(REPO_ROOT / 'scripts')!r}); "
                    "import validate_pr; print(validate_pr.get_changed_files())"
                )],
                cwd=tmp, capture_output=True, text=True, timeout=60, check=False,
            )
        self.assertEqual(proc.returncode, 0, proc.stderr)
        self.assertIn("bios/x.bin", proc.stdout)
        self.assertIn("staged changes only", proc.stderr)


class RefreshFailuresAreFailures(unittest.TestCase):
    def test_a_failed_refresh_is_returned_and_exits_nonzero(self):
        report = {"entries": [{"status": "UPDATED", "key": "dolphin-sys"},
                              {"status": "OK", "key": "ppsspp-assets"}]}
        with mock.patch.object(
            check_buildbot_system.subprocess, "run",
            return_value=subprocess.CompletedProcess([], 1),
        ):
            self.assertEqual(check_buildbot_system.update_changed(report), ["dolphin-sys"])
        source = (REPO_ROOT / "scripts" / "check_buildbot_system.py").read_text(encoding="utf-8")
        self.assertIn("failed = update_changed(report)", source)
        self.assertIn("sys.exit(1)", source[source.index("failed = update_changed(report)"):])


class AnEmptyExtractionKeepsTheCache(unittest.TestCase):
    """An archive without the cited subtree replaced the cache with an empty
    directory, recorded the version and reported success."""

    def setUp(self):
        import refresh_data_dirs

        self.module = refresh_data_dirs
        scratch = Path(__file__).resolve().parent.parent / "tmp"
        scratch.mkdir(exist_ok=True)
        self.root = Path(tempfile.mkdtemp(dir=scratch))
        self.addCleanup(shutil.rmtree, self.root, True)
        self.cache = self.root / "cache"
        self.cache.mkdir()
        (self.cache / "keep.dat").write_bytes(b"cached")

    def test_a_tarball_without_the_subtree(self):
        import tarfile

        archive = self.root / "archive.tar.gz"
        payload = self.root / "a.txt"
        payload.write_bytes(b"x")
        with tarfile.open(archive, "w:gz") as tf:
            tf.add(payload, arcname="repo-main/OtherDir/a.txt")
        with self.assertRaises(self.module.NothingExtractedError):
            self.module._download_and_extract(
                archive.as_uri(), "repo-main/Data/Sys", str(self.cache), []
            )
        self.assertEqual((self.cache / "keep.dat").read_bytes(), b"cached")

    def test_a_zip_with_no_file(self):
        import zipfile

        archive = self.root / "archive.zip"
        with zipfile.ZipFile(archive, "w") as zf:
            zf.writestr("only/", b"")
        with self.assertRaises(self.module.NothingExtractedError):
            self.module._download_and_extract_zip(archive.as_uri(), str(self.cache))
        self.assertEqual((self.cache / "keep.dat").read_bytes(), b"cached")


class TheVersionIsReadBeforeTheDownload(unittest.TestCase):
    """The buildbot republishes nightly. Read after the download, the tag
    named the new build while the cache held the old one, and every later
    run called it up to date."""

    def test_a_build_published_during_the_download(self):
        import refresh_data_dirs as rdd

        root = Path(tempfile.mkdtemp(dir=REPO_ROOT / "tmp"))
        self.addCleanup(shutil.rmtree, root, True)
        state = {"downloaded": False}

        def etag(_url):
            return "build-2" if state["downloaded"] else "build-1"

        def download(*_args, **_kwargs):
            state["downloaded"] = True
            return 3

        versions = root / "versions.json"
        entry = {"source_type": "zip", "source_url": "https://example.invalid/Sys.zip",
                 "local_cache": str(root / "cache")}
        with mock.patch.object(rdd, "_get_remote_etag", etag), \
                mock.patch.object(rdd, "_download_and_extract_zip", download):
            self.assertTrue(rdd._refresh_entry("sys", entry, True, False, str(versions)))
        self.assertEqual(json.loads(versions.read_text())["sys"]["sha"], "build-1")


if __name__ == "__main__":
    unittest.main()