"""Open Graph repo card tests — musehub#129 OG_01 through OG_06."""

from __future__ import annotations

from datetime import datetime, timezone

import pytest
from httpx import AsyncClient
from sqlalchemy.ext.asyncio import AsyncSession

from musehub.core.genesis import compute_identity_id, compute_repo_id
from musehub.db.musehub_repo_models import MusehubRepo
from musehub.services.opengraph_cards import compute_content_hash
from musehub.services.opengraph_renderer import StubOpenGraphRenderer, reset_renderer_for_tests

_PNG_MAGIC = b"\x89PNG\r\n\x1a\n"


async def _make_repo(
    db: AsyncSession,
    owner: str = "alice",
    slug: str = "og-test",
    *,
    description: str = "A test repository for OG cards",
    visibility: str = "public",
) -> MusehubRepo:
    created_at = datetime.now(tz=timezone.utc)
    owner_id = compute_identity_id(owner.encode())
    repo = MusehubRepo(
        repo_id=compute_repo_id(owner_id, slug, "code", created_at.isoformat()),
        name=slug,
        owner=owner,
        slug=slug,
        visibility=visibility,
        description=description,
        owner_user_id=owner_id,
        created_at=created_at,
        updated_at=created_at,
    )
    db.add(repo)
    await db.commit()
    await db.refresh(repo)
    return repo


@pytest.fixture(autouse=True)
def _reset_og_renderer() -> None:
    reset_renderer_for_tests()


# ---------------------------------------------------------------------------
# OG_01 — endpoint returns PNG
# ---------------------------------------------------------------------------


async def test_og01_opengraph_image_returns_png(
    client: AsyncClient,
    db_session: AsyncSession,
) -> None:
    await _make_repo(db_session, owner="alice", slug="og-test")
    resp = await client.get("/alice/og-test/opengraph-image")
    assert resp.status_code == 200
    assert resp.headers.get("content-type", "").startswith("image/png")
    assert resp.content[:8] == _PNG_MAGIC


async def test_og01_private_repo_returns_404(
    client: AsyncClient,
    db_session: AsyncSession,
) -> None:
    await _make_repo(db_session, owner="alice", slug="secret", visibility="private")
    resp = await client.get("/alice/secret/opengraph-image")
    assert resp.status_code == 404


# ---------------------------------------------------------------------------
# OG_02 — description in template context (stub renderer)
# ---------------------------------------------------------------------------


async def test_og02_description_in_renderer_context(
    client: AsyncClient,
    db_session: AsyncSession,
) -> None:
    desc = "Unique OG description string for OG_02"
    await _make_repo(db_session, owner="bob", slug="desc-repo", description=desc)
    await client.get("/bob/desc-repo/opengraph-image")
    ctx = StubOpenGraphRenderer.last_context
    assert ctx is not None
    assert ctx.description == desc


async def test_og02_empty_description_uses_fallback(
    client: AsyncClient,
    db_session: AsyncSession,
) -> None:
    await _make_repo(db_session, owner="carol", slug="no-desc", description="")
    await client.get("/carol/no-desc/opengraph-image")
    ctx = StubOpenGraphRenderer.last_context
    assert ctx is not None
    assert "carol" in ctx.description


# ---------------------------------------------------------------------------
# OG_03 — avatar context for registered and unregistered owners
# ---------------------------------------------------------------------------


async def test_og03_avatar_b64_present_for_unregistered_owner(
    client: AsyncClient,
    db_session: AsyncSession,
) -> None:
    await _make_repo(db_session, owner="dave", slug="avatar-repo")
    await client.get("/dave/avatar-repo/opengraph-image")
    ctx = StubOpenGraphRenderer.last_context
    assert ctx is not None
    assert len(ctx.avatar_png_b64) > 20


# ---------------------------------------------------------------------------
# OG_04 — stats reflect DB (commits count via stub context)
# ---------------------------------------------------------------------------


async def test_og04_stats_in_renderer_context(
    client: AsyncClient,
    db_session: AsyncSession,
) -> None:
    await _make_repo(db_session, owner="erin", slug="stats-repo")
    await client.get("/erin/stats-repo/opengraph-image")
    ctx = StubOpenGraphRenderer.last_context
    assert ctx is not None
    assert ctx.total_commits >= 0
    assert ctx.fork_count == 0
    assert ctx.open_issue_count == 0


# ---------------------------------------------------------------------------
# OG_05 — cache: second request does not re-render; metadata change does
# ---------------------------------------------------------------------------


async def test_og05_cache_hit_avoids_second_render(
    client: AsyncClient,
    db_session: AsyncSession,
) -> None:
    repo = await _make_repo(db_session, owner="frank", slug="cache-repo")
    await client.get("/frank/cache-repo/opengraph-image")
    assert StubOpenGraphRenderer.render_count == 1
    await client.get("/frank/cache-repo/opengraph-image")
    assert StubOpenGraphRenderer.render_count == 1

    repo.description = "Updated description busts the cache"
    await db_session.commit()
    await client.get("/frank/cache-repo/opengraph-image")
    assert StubOpenGraphRenderer.render_count == 2


# ---------------------------------------------------------------------------
# OG_06 — repo page HTML contains absolute og:image with ?cb=
# ---------------------------------------------------------------------------


async def test_og06_repo_page_emits_og_image_meta(
    client: AsyncClient,
    db_session: AsyncSession,
) -> None:
    await _make_repo(db_session, owner="grace", slug="meta-repo", description="OG meta test")
    resp = await client.get("/grace/meta-repo")
    assert resp.status_code == 200
    assert 'property="og:image"' in resp.text
    assert "opengraph-image?cb=" in resp.text
    assert resp.text.index("http") < resp.text.index("opengraph-image")


async def test_og06_twitter_large_image_card(
    client: AsyncClient,
    db_session: AsyncSession,
) -> None:
    await _make_repo(db_session, owner="hank", slug="twitter-repo")
    resp = await client.get("/hank/twitter-repo")
    assert 'name="twitter:card"' in resp.text
    assert "summary_large_image" in resp.text


# ---------------------------------------------------------------------------
# Unit — content hash stability
# ---------------------------------------------------------------------------


def test_content_hash_changes_when_description_changes() -> None:
    from musehub.services.opengraph_cards import OpenGraphCardContext, description_fallback

    base = OpenGraphCardContext(
        owner="a",
        repo_slug="b",
        description=description_fallback("a"),
        domain_id="code",
        total_commits=1,
        fork_count=0,
        open_issue_count=0,
        owner_identity_hex="abc",
        identity_type="agent",
        avatar_png_b64="e30=",
    )
    h1 = compute_content_hash(base)
    changed = OpenGraphCardContext(
        owner=base.owner,
        repo_slug=base.repo_slug,
        description="different",
        domain_id=base.domain_id,
        total_commits=base.total_commits,
        fork_count=base.fork_count,
        open_issue_count=base.open_issue_count,
        owner_identity_hex=base.owner_identity_hex,
        identity_type=base.identity_type,
        avatar_png_b64=base.avatar_png_b64,
    )
    h2 = compute_content_hash(changed)
    assert h1 != h2


# ---------------------------------------------------------------------------
# Security — slug injection blocked at validation layer
# ---------------------------------------------------------------------------


async def test_og_security_invalid_slug_rejected(client: AsyncClient) -> None:
    resp = await client.get("/alice/not%20valid/opengraph-image")
    assert resp.status_code == 422