"""Tests for cache loading and saving."""

import json
import pytest
from pathlib import Path

import debian_todo


class TestLoadCache:
    """Tests for load_cache function."""

    def test_returns_none_when_file_missing(self, tmp_path, monkeypatch):
        cache_file = tmp_path / "cache.json"
        monkeypatch.setattr(debian_todo, "CACHE_PATH", cache_file)

        result = debian_todo.load_cache([])
        assert result is None

    def test_returns_none_on_invalid_json(self, tmp_path, monkeypatch):
        cache_file = tmp_path / "cache.json"
        cache_file.write_text("not valid json")
        monkeypatch.setattr(debian_todo, "CACHE_PATH", cache_file)

        result = debian_todo.load_cache([])
        assert result is None

    def test_returns_none_on_version_mismatch(self, tmp_path, monkeypatch):
        cache_file = tmp_path / "cache.json"
        cache_file.write_text(json.dumps({
            "cache_version": debian_todo.CACHE_VERSION - 1,
            "sources_mtimes": {},
            "vcs_by_source": {},
        }))
        monkeypatch.setattr(debian_todo, "CACHE_PATH", cache_file)

        result = debian_todo.load_cache([])
        assert result is None

    def test_returns_none_when_mtime_mismatch(self, tmp_path, monkeypatch):
        source_file = tmp_path / "Sources"
        source_file.write_text("dummy")
        cache_file = tmp_path / "cache.json"
        cache_file.write_text(json.dumps({
            "cache_version": debian_todo.CACHE_VERSION,
            "sources_mtimes": {str(source_file): 0.0},
            "vcs_by_source": {},
        }))
        monkeypatch.setattr(debian_todo, "CACHE_PATH", cache_file)

        result = debian_todo.load_cache([str(source_file)])
        assert result is None

    def test_returns_cache_when_valid(self, tmp_path, monkeypatch):
        import os

        source_file = tmp_path / "Sources"
        source_file.write_text("dummy")
        mtime = os.path.getmtime(str(source_file))

        cache_file = tmp_path / "cache.json"
        cache_file.write_text(json.dumps({
            "cache_version": debian_todo.CACHE_VERSION,
            "sources_mtimes": {str(source_file): mtime},
            "vcs_by_source": {
                "foo": {"vcs_git": "python-team", "uploaders": "John <j@e.com>"}
            },
        }))
        monkeypatch.setattr(debian_todo, "CACHE_PATH", cache_file)

        result = debian_todo.load_cache([str(source_file)])
        assert result == {"foo": {"vcs_git": "python-team", "uploaders": "John <j@e.com>"}}

    def test_normalizes_legacy_string_format(self, tmp_path, monkeypatch):
        import os

        source_file = tmp_path / "Sources"
        source_file.write_text("dummy")
        mtime = os.path.getmtime(str(source_file))

        cache_file = tmp_path / "cache.json"
        cache_file.write_text(json.dumps({
            "cache_version": debian_todo.CACHE_VERSION,
            "sources_mtimes": {str(source_file): mtime},
            "vcs_by_source": {"foo": "python-team"},  # legacy string format
        }))
        monkeypatch.setattr(debian_todo, "CACHE_PATH", cache_file)

        result = debian_todo.load_cache([str(source_file)])
        assert result == {"foo": {"vcs_git": "python-team", "uploaders": ""}}


class TestSaveCache:
    """Tests for save_cache function."""

    def test_saves_cache_file(self, tmp_path, monkeypatch):
        import os

        source_file = tmp_path / "Sources"
        source_file.write_text("dummy")
        cache_file = tmp_path / "cache.json"
        monkeypatch.setattr(debian_todo, "CACHE_PATH", cache_file)

        vcs_by_source = {"foo": {"vcs_git": "python-team", "uploaders": ""}}
        debian_todo.save_cache([str(source_file)], vcs_by_source)

        assert cache_file.exists()
        data = json.loads(cache_file.read_text())
        assert data["cache_version"] == debian_todo.CACHE_VERSION
        assert data["vcs_by_source"] == vcs_by_source
        assert str(source_file) in data["sources_mtimes"]

    def test_handles_missing_source_file(self, tmp_path, monkeypatch):
        cache_file = tmp_path / "cache.json"
        monkeypatch.setattr(debian_todo, "CACHE_PATH", cache_file)

        debian_todo.save_cache(["/nonexistent/file"], {})

        # Should not create cache file if source file is missing
        assert not cache_file.exists()