# Adapt from https://github.com/vllm-project/vllm/blob/main/vllm/v1/worker/gpu/block_table.py
# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
#
# 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.
# This file is a part of the vllm-ascend project.
#

import torch
from vllm.v1.worker.gpu.block_table import BlockTables


class AscendBlockTables(BlockTables):
    """Block table for Ascend NPUs."""

    def __init__(
        self,
        block_sizes: list[int],
        max_num_reqs: int,
        max_num_batched_tokens: int,
        max_model_len: int,
        device: torch.device,
        cp_size: int = 1,
        cp_rank: int = 0,
        cp_interleave: int = 1,
    ):
        super().__init__(
            block_sizes,
            max_num_reqs,
            max_num_batched_tokens,
            max_model_len,
            device,
            cp_size,
            cp_rank,
            cp_interleave,
        )
        # because we will override these attribute, delete these attribute to
        # make sure it's collected by python gc immediately.
        del self.slot_mappings
        # vllm-ascend' reshape_and_cache function requires slot_mappings to be int32.
        # so we need to redefine slot_mappings to be int32.
        self.slot_mappings: torch.Tensor = torch.zeros(
            self.num_kv_cache_groups,
            self.max_num_batched_tokens,
            dtype=torch.int32,
            device=self.device,
        )