"""Where uploaded documents live (OPS-011).

Contract paths were absolute and built from `os.getcwd()`, so the storage
root followed whatever directory the process was started from. That is a
defect on its own — a server restarted from elsewhere writes new contracts
into a new tree and cannot read the old ones, while the database goes on
saying they are there — and it is what made a release-directory deployment
impossible: every stored path would point inside a release about to be
replaced.

The compatibility case is the one that matters most here. Rows written
before this change hold absolute paths, and they have to keep working
without a data migration, because the migration tooling does not exist yet
(DB-002, blocked).
"""

import os

import pytest

from app.storage import CONTRACTS_DIR, document_path, documents_root


class TestDocumentsRoot:
    def test_the_environment_wins(self, tmp_path, monkeypatch):
        monkeypatch.setenv('DOCUMENTS_ROOT', str(tmp_path / 'elsewhere'))

        assert documents_root() == str(tmp_path / 'elsewhere')

    def test_a_relative_override_is_made_absolute(self, monkeypatch):
        monkeypatch.setenv('DOCUMENTS_ROOT', 'docs-here')

        assert os.path.isabs(documents_root())

    def test_the_default_does_not_follow_the_working_directory(self, tmp_path, monkeypatch):
        """The whole point. `os.getcwd()` made this move; the package
        location does not."""
        monkeypatch.delenv('DOCUMENTS_ROOT', raising=False)
        before = documents_root()

        monkeypatch.chdir(tmp_path)
        after = documents_root()

        assert before == after

    def test_the_default_sits_beside_the_package(self, monkeypatch):
        monkeypatch.delenv('DOCUMENTS_ROOT', raising=False)

        # From the module file, not from `app.__file__`: `app` has no
        # __init__.py, so it is a namespace package and __file__ is None.
        from app import storage

        package_dir = os.path.dirname(os.path.abspath(storage.__file__))
        expected = os.path.join(os.path.dirname(package_dir), 'documents')
        assert documents_root() == expected


class TestDocumentPath:
    def test_a_relative_path_is_resolved_against_the_root(self, tmp_path, monkeypatch):
        monkeypatch.setenv('DOCUMENTS_ROOT', str(tmp_path))

        resolved = document_path(os.path.join(CONTRACTS_DIR, 'abc.pdf'))

        assert resolved == str(tmp_path / CONTRACTS_DIR / 'abc.pdf')

    def test_an_absolute_path_is_left_alone(self, tmp_path, monkeypatch):
        """Rows written before this module existed. They must keep resolving
        to where the file actually is, or every contract uploaded so far
        becomes a 500 on download the day this ships."""
        monkeypatch.setenv('DOCUMENTS_ROOT', str(tmp_path / 'new-root'))
        legacy = os.path.abspath(os.path.join('C:' + os.sep, 'old', 'place', 'abc.pdf'))

        assert document_path(legacy) == legacy

    def test_moving_the_root_moves_new_documents_and_not_old_ones(self, tmp_path, monkeypatch):
        relative = os.path.join(CONTRACTS_DIR, 'abc.pdf')
        legacy = os.path.abspath(os.path.join(str(tmp_path), 'legacy', 'abc.pdf'))

        monkeypatch.setenv('DOCUMENTS_ROOT', str(tmp_path / 'one'))
        first_new, first_old = document_path(relative), document_path(legacy)

        monkeypatch.setenv('DOCUMENTS_ROOT', str(tmp_path / 'two'))
        second_new, second_old = document_path(relative), document_path(legacy)

        assert first_new != second_new, 'a release switch has to move new documents'
        assert first_old == second_old, 'and must not move the ones already filed'


class TestThroughTheUploadRoute:
    @pytest.fixture
    def uploaded(self, app, client, as_role, make_user):
        """A contract filed by an admin for a player."""
        as_role('admin')
        player_id = make_user('player')

        response = client.post(
            '/users/contracts/upload',
            data={
                'player_id': str(player_id),
                'notes': 'Season contract',
                'contract_file': (_pdf(), 'contract.pdf'),
            },
            content_type='multipart/form-data',
            follow_redirects=True,
        )
        assert response.status_code == 200
        return player_id

    def test_the_stored_path_is_relative(self, app, uploaded):
        from app.models import Contract

        with app.app_context():
            contract = Contract.query.one()
            assert not os.path.isabs(contract.file_path), (
                'an absolute path pins the file to the directory the process '
                'was started from — the one thing a release switch changes'
            )
            assert contract.file_path.startswith(CONTRACTS_DIR)

    def test_the_file_lands_under_the_configured_root(self, app, uploaded):
        from app.models import Contract

        with app.app_context():
            contract = Contract.query.one()
            resolved = document_path(contract.file_path)

        assert os.path.exists(resolved)
        assert resolved.startswith(documents_root())

    def test_it_can_be_downloaded_back(self, app, client, uploaded):
        from app.models import Contract

        with app.app_context():
            contract_id = Contract.query.one().id

        response = client.get(f'/users/contracts/{contract_id}/download')

        assert response.status_code == 200
        assert response.data.startswith(b'%PDF-')


def _pdf():
    """The smallest thing pdf_upload_error accepts."""
    import io

    return io.BytesIO(b'%PDF-1.4\n%%EOF\n')