"""Federation app fragment endpoints.

Exposes HTML fragments at ``/internal/fragments/<type>`` for consumption
by other coop apps via the fragment client.
"""

from __future__ import annotations

from quart import Blueprint, Response, request

from shared.infrastructure.fragments import FRAGMENT_HEADER
from shared.sexp.jinja_bridge import sexp


def register():
    bp = Blueprint("fragments", __name__, url_prefix="/internal/fragments")

    _handlers: dict[str, object] = {}

    @bp.before_request
    async def _require_fragment_header():
        if not request.headers.get(FRAGMENT_HEADER):
            return Response("", status=403)

    @bp.get("/<fragment_type>")
    async def get_fragment(fragment_type: str):
        handler = _handlers.get(fragment_type)
        if handler is None:
            return Response("", status=200, content_type="text/html")
        html = await handler()
        return Response(html, status=200, content_type="text/html")

    # --- link-card fragment: actor profile preview card --------------------------

    def _render_federation_link_card(actor, link: str) -> str:
        return sexp(
            '(~link-card :link link :title title :image image'
            ' :icon "fas fa-user" :subtitle username'
            ' :detail summary :data-app "federation")',
            link=link,
            title=actor.display_name or actor.preferred_username,
            image=None,
            username=f"@{actor.preferred_username}" if actor.preferred_username else None,
            summary=actor.summary,
        )

    async def _link_card_handler():
        from quart import g
        from shared.services.registry import services
        from shared.infrastructure.urls import federation_url

        username = request.args.get("username", "")
        slug = request.args.get("slug", "")
        keys_raw = request.args.get("keys", "")

        # Batch mode
        if keys_raw:
            usernames = [k.strip() for k in keys_raw.split(",") if k.strip()]
            parts = []
            for u in usernames:
                parts.append(f"<!-- fragment:{u} -->")
                actor = await services.federation.get_actor_by_username(g.s, u)
                if actor:
                    parts.append(_render_federation_link_card(
                        actor, federation_url(f"/users/{actor.preferred_username}"),
                    ))
            return "\n".join(parts)

        # Single mode
        lookup = username or slug
        if not lookup:
            return ""
        actor = await services.federation.get_actor_by_username(g.s, lookup)
        if not actor:
            return ""
        return _render_federation_link_card(
            actor, federation_url(f"/users/{actor.preferred_username}"),
        )

    _handlers["link-card"] = _link_card_handler

    bp._fragment_handlers = _handlers

    return bp