"""Regression coverage for raising the supported browser floor.

Raising ``CONSTRAINTS.MIN_VERSION`` is how the library forces an existing
install to upgrade when it can no longer talk to the old browser. That path
had been dead since the floor was dropped to ``alpha.1``, and it hid a bug:
``camoufox_path`` probed ``INSTALL_DIR/version.json``, which only the
pre-multiversion flat layout ever wrote, so a below-floor versioned install
raised ``FileNotFoundError`` instead of falling through to a fetch.
"""

import json

import pytest

from camoufox import multiversion, pkgman
from camoufox.exceptions import UnsupportedVersion


def _install(tmp_path, monkeypatch, layout, build, floor):
    """Build an install dir in the given layout and point the library at it."""
    root = tmp_path / "cache"
    root.mkdir()
    (root / ".0.5_FLAG").write_text("")
    (root / "repo_cache.json").write_text("{}")

    if layout == "versioned":
        relative = f"browsers/official/152.0.4-{build}"
        (root / "config.json").write_text(json.dumps({"active_version": relative}))
        version_dir = root / relative
        version_dir.mkdir(parents=True)
    else:
        (root / "config.json").write_text("{}")
        version_dir = root
    (version_dir / "version.json").write_text(
        json.dumps({"version": "152.0.4", "build": build})
    )

    for module in (pkgman, multiversion):
        monkeypatch.setattr(module, "INSTALL_DIR", root)
    monkeypatch.setattr(multiversion, "BROWSERS_DIR", root / "browsers")
    monkeypatch.setattr(multiversion, "CONFIG_FILE", root / "config.json")
    monkeypatch.setattr(multiversion, "COMPAT_FLAG", root / ".0.5_FLAG")
    monkeypatch.setattr(pkgman, "VERSION_MIN", pkgman.Version(build=floor))
    return root


@pytest.mark.parametrize("layout", ["versioned", "legacy"])
def test_below_floor_install_is_reported_as_outdated(tmp_path, monkeypatch, layout):
    """A build under the floor must report as outdated, never as missing."""
    _install(tmp_path, monkeypatch, layout, build="beta.29", floor="beta.30")

    with pytest.raises(UnsupportedVersion):
        pkgman.camoufox_path(download_if_missing=False)


@pytest.mark.parametrize("layout", ["versioned", "legacy"])
def test_at_floor_install_is_kept(tmp_path, monkeypatch, layout):
    """A build at the floor is still served, in either layout."""
    root = _install(tmp_path, monkeypatch, layout, build="beta.30", floor="beta.30")

    resolved = pkgman.camoufox_path(download_if_missing=False)

    expected = root if layout == "legacy" else root / "browsers/official/152.0.4-beta.30"
    assert resolved == expected


def test_below_floor_install_triggers_a_fetch(tmp_path, monkeypatch):
    """The default path upgrades the install instead of raising."""
    root = _install(tmp_path, monkeypatch, "versioned", build="beta.29", floor="beta.30")
    installed = []

    class StubFetcher:
        def install(self):
            installed.append(True)
            relative = "browsers/official/152.0.4-beta.30"
            version_dir = root / relative
            version_dir.mkdir(parents=True)
            (version_dir / "version.json").write_text(
                json.dumps({"version": "152.0.4", "build": "beta.30"})
            )
            (root / "config.json").write_text(json.dumps({"active_version": relative}))

    monkeypatch.setattr(pkgman, "CamoufoxFetcher", StubFetcher)

    resolved = pkgman.camoufox_path()

    assert installed == [True]
    assert resolved == root / "browsers/official/152.0.4-beta.30"


def test_root_probe_tolerates_the_versioned_layout(tmp_path, monkeypatch):
    """The root probe reports False, rather than raising, with no root file."""
    root = tmp_path / "cache"
    root.mkdir()
    monkeypatch.setattr(pkgman, "INSTALL_DIR", root)

    assert pkgman._root_install_supported() is False