"""Single-file structure tests — verify open-transcode.py is the program.

The application ships as ONE self-contained module: ``open-transcode.py``
(everything inlined; runs with only Python + PySide6). These tests pin
that arrangement:

  - the module loads cleanly via the conftest program loader,
  - its metadata (version / author / contact / license) is intact,
  - the expected public symbol surface is present (the tables, the
    worker, the UI class, the probe helpers, the CLI parser),
  - the file stays self-contained — a stray ``import opentranscode``
    would reintroduce a second copy of the program and fails here.

Runs WITHOUT PySide6 installed (the conftest installs stubs first).
"""
import re

from conftest import OPENTRANSCODE_SCRIPT_PATH, load_program_module

# Every symbol the app's own tests and tooling reach for — one flat set
# now that the program is a single module.
EXPECTED_PROGRAM_SYMBOLS = {
    # profile tables + helpers
    "AUDIO_PROFILES", "CONTAINER_PROFILES", "DEFAULT_INPUT_EXTENSIONS",
    "FFMPEG_LIB_KEY_MAP", "RESOLUTION_PRESETS", "SUBTITLE_OPTIONS",
    "VIDEO_CODECS", "TITLE_ARTIFACT_TOKENS", "THEORA_Q_RANGE",
    "AudioProfile", "ContainerProfile", "ResolutionProfile",
    "VideoCodecProfile", "clean_title", "ffmpeg_lib_key_for",
    "theora_quality_from_crf",
    # encode pipeline
    "EncoderWorker", "scan_input_files", "resolve_gpu_encoder",
    "plan_hybrid", "HybridPlan", "KeepAwake",
    # environment
    "EnvProbe", "probe_environment", "detect_distro", "DistroProfile",
    "DISTRO_REGISTRY", "CpuTopology", "GPU_PROFILES", "match_gpu_profile",
    "_probe_vs_source_plugins", "_identify_file_type",
    # UI + CLI
    "OpenCodecMaster", "launch_gui", "SourceBuildWorker",
    "RadioKnob", "build_parser", "main",
}


# ─────────────────────────────────────────────────────────────────────────────
#  Tests
# ─────────────────────────────────────────────────────────────────────────────


class TestProgramMetadata:
    def test_version_is_pep440_compliant(self):
        v = load_program_module().__version__
        assert isinstance(v, str)
        parts = v.split(".")
        assert len(parts) >= 3, f"Version '{v}' should have at least major.minor.patch"
        assert parts[0].isdigit() and parts[1].isdigit(), \
            f"Version '{v}' should be PEP 440 numeric"

    def test_author_and_contact_are_set(self):
        m = load_program_module()
        assert m.__author__ == "Jeremy Anderson"
        assert m.__email__ == "info@dcos.net"
        assert "dcos.net" in m.__website__

    def test_license_is_agpl(self):
        assert "AGPL" in load_program_module().__license__


class TestSingleFileArrangement:
    def test_program_file_exists_at_repo_root(self):
        assert OPENTRANSCODE_SCRIPT_PATH.is_file()

    def test_no_second_copy_of_the_program(self):
        """The opentranscode/ package directory must not exist — the
        single file is the whole program. Two copies cannot drift if
        there is only one."""
        repo_root = OPENTRANSCODE_SCRIPT_PATH.parent
        assert not (repo_root / "opentranscode").exists(), \
            "opentranscode/ package directory exists alongside the " \
            "single-file program — pick one copy"

    def test_program_file_is_self_contained(self):
        """No import of a package copy from inside the program file."""
        src = OPENTRANSCODE_SCRIPT_PATH.read_text()
        stray = re.findall(r"^\s*(?:from|import)\s+opentranscode.*$", src, re.M)
        assert stray == [], f"program imports its old package copy: {stray}"


class TestPublicSurface:
    def test_expected_symbols_present(self):
        m = load_program_module()
        missing = sorted(n for n in EXPECTED_PROGRAM_SYMBOLS
                         if not hasattr(m, n))
        assert missing == [], f"missing program symbols: {missing}"

    def test_video_codecs_table_populated(self):
        VIDEO_CODECS = load_program_module().VIDEO_CODECS
        assert len(VIDEO_CODECS) >= 4, \
            "Should have at least 4 video codecs (AV1, VP9, x265, Theora)"
        labels = [c.label for c in VIDEO_CODECS]
        assert any("AV1" in l for l in labels)
        assert any("VP9" in l for l in labels)
        assert any("x265" in l or "HEVC" in l for l in labels)
        assert any("Theora" in l for l in labels)

    def test_audio_profiles_have_ffmpeg_encoder_name(self):
        AUDIO_PROFILES = load_program_module().AUDIO_PROFILES
        for ap in AUDIO_PROFILES:
            assert ap.ffmpeg_encoder_name, \
                f"AudioProfile '{ap.label}' has empty ffmpeg_encoder_name"

    def test_distro_registry_has_six_entries(self):
        DISTRO_REGISTRY = load_program_module().DISTRO_REGISTRY
        families = {e.family for e in DISTRO_REGISTRY}
        assert {"arch", "debian", "redhat", "suse", "nixos"} <= families
        assert len(DISTRO_REGISTRY) >= 6


class TestCLIParser:
    def test_build_parser_parses_empty_argv(self):
        args = load_program_module().build_parser().parse_args([])
        assert args.engine == "auto"
        assert args.verbose is False

    def test_build_parser_accepts_all_flags(self):
        args = load_program_module().build_parser().parse_args([
            "--verbose", "--use-av1an", "--engine", "hybrid",
            "--timeout", "3600", "--force-reencode",
        ])
        assert args.verbose is True
        assert args.use_av1an is True
        assert args.engine == "hybrid"
        assert args.timeout == 3600
        assert args.skip_existing is False