"""End-to-end write-path test (SHARD-WP-0008 T6)."""

from shard_wiki import InformationSpace
from shard_wiki.adapters import FolderAdapter
from shard_wiki.coordination import ApplyStatus
from shard_wiki.provenance import OverlayState


def _folder(tmp_path, name, files, writable=False):
    root = tmp_path / name
    root.mkdir(parents=True, exist_ok=True)
    for rel, text in files.items():
        (root / rel).write_text(text, encoding="utf-8")
    return FolderAdapter(name, root, writable=writable)


def test_edit_writethrough_on_writable_shard(tmp_path):
    space = InformationSpace("team")
    space.attach(_folder(tmp_path, "wikiW", {"Home.md": "old"}, writable=True))

    result = space.edit("Home", "new content")
    assert result.status is ApplyStatus.APPLIED
    assert space.read("Home").body == "new content"  # persisted to the shard
    assert space.read("Home").envelope.overlay_state is OverlayState.NONE  # overlay closed


def test_edit_on_readonly_shard_keeps_local_draft(tmp_path):
    space = InformationSpace("team")
    space.attach(_folder(tmp_path, "wikiRO", {"Home.md": "canon"}))

    result = space.edit("Home", "my local edit")
    assert result.status is ApplyStatus.KEPT_DRAFT
    # source untouched; union shows the draft as local truth, clearly flagged
    page = space.read("Home")
    assert page.body == "my local edit"
    assert page.envelope.overlay_state is OverlayState.DRAFT


def test_explicit_overlay_then_apply(tmp_path):
    space = InformationSpace("team")
    space.attach(_folder(tmp_path, "wikiW", {"Doc.md": "v1"}, writable=True))
    ov = space.overlay("Doc", "v2")
    assert space.read("Doc").envelope.overlay_state is OverlayState.DRAFT  # pending
    result = space.apply_overlay(ov.overlay_id)
    assert result.status is ApplyStatus.APPLIED
    assert space.read("Doc").body == "v2"


def test_stale_overlay_refuses_after_external_change(tmp_path):
    space = InformationSpace("team")
    shard = _folder(tmp_path, "wikiW", {"Doc.md": "v1"}, writable=True)
    space.attach(shard)
    ov = space.overlay("Doc", "from-v1")
    # an external write moves the shard under the overlay
    shard.write("Doc", "v1-prime")
    result = space.apply_overlay(ov.overlay_id)
    assert result.status is ApplyStatus.REFUSED_DRIFT
    assert space.union.shard("wikiW").read("Doc").body == "v1-prime"  # not clobbered