membersystem/src/utils/view_utils.py

import contextlib
from dataclasses import dataclass

from django.core.exceptions import FieldError
from django.core.paginator import Paginator
from django.db.models import Model
from django.http import HttpRequest
from django.http import HttpResponse
from django.urls import reverse
from zen_queries import render


@dataclass
class Row:
    """
    A row in a table.
    """

    data: dict[str, str]
    actions: list[dict[str, str]]


@dataclass
class RowAction:
    """
    An action that can be performed on a row in a table.
    """

    label: str
    url_name: str
    url_kwargs: dict[str, str]

    def render(self, obj) -> dict[str, str]:
        """
        Render the action as a dictionary for the given object.
        """
        url = reverse(
            self.url_name,
            kwargs={key: getattr(obj, value) for key, value in self.url_kwargs.items()},
        )
        return {"label": self.label, "url": url}


def render_list(
    request: HttpRequest,
    objects: list["Model"],
    columns: list[tuple[str, str]],
    row_actions: list[RowAction] = None,
    list_actions: list[tuple[str, str]] = None,
    paginate_by: int = None,
) -> HttpResponse:
    """
    Render a list of objects with a table.
    """

    # TODO: List actions

    total_count = len(objects)

    order_by = request.GET.get("order_by")

    if order_by:
        with contextlib.suppress(FieldError):
            objects = objects.order_by(order_by)

    if paginate_by:
        paginator = Paginator(object_list=objects, per_page=paginate_by)
        page = paginator.get_page(request.GET.get("page"))
        objects = page.object_list

    rows = []
    for obj in objects:
        row = Row(
            data={column: getattr(obj, column[0]) for column in columns},
            actions=[action.render(obj) for action in row_actions],
        )
        rows.append(row)

    context = {
        "rows": rows,
        "columns": columns,
        "row_actions": row_actions,
        "list_actions": list_actions,
        "total_count": total_count,
        "order_by": order_by,
    }

    if paginate_by:
        context |= {
            "page": page,
            "is_paginated": True,
        }

    return render(
        request=request,
        template_name="utils/list.html",
        context=context,
    )