"""
Copyright 2024-2026 ChatterMate

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
"""

import math

from pydantic import BaseModel


class Pagination(BaseModel):
    """Standard list-endpoint pagination block (shape matches the knowledge
    API's inline dicts: total / page / page_size / total_pages)."""
    total: int
    page: int
    page_size: int
    total_pages: int

    @classmethod
    def build(cls, total: int, page: int, page_size: int) -> "Pagination":
        return cls(
            total=total,
            page=page,
            page_size=page_size,
            total_pages=max(1, math.ceil(total / page_size)) if total else 0,
        )