"""Shared pagination helpers for HTMX table cards (admin screens, scopes page)."""

import math
import urllib.parse


def query_url(base_path: str, params: dict) -> str:
    clean = {k: v for k, v in params.items() if v not in (None, "", 0)}
    return f"{base_path}?{urllib.parse.urlencode(clean)}"


def paginate(
    base_path: str,
    filter_params: dict,
    page: int,
    page_size: int,
    total: int,
    target_id: str,
) -> dict:
    total_pages = max(1, math.ceil(total / page_size))
    page = max(1, min(page, total_pages))
    skip = (page - 1) * page_size

    def _url(p: int) -> str:
        return query_url(
            base_path, {**filter_params, "page": p, "page_size": page_size}
        )

    return {
        "page": page,
        "page_size": page_size,
        "total": total,
        "total_pages": total_pages,
        "skip": skip,
        "showing_from": skip + 1 if total > 0 else 0,
        "showing_to": min(skip + page_size, total),
        "prev_url": _url(page - 1) if page > 1 else None,
        "next_url": _url(page + 1) if page < total_pages else None,
        "target_id": target_id,
    }