#  ------------------------------------------------------------------------------------------
#  Copyright (c) Microsoft Corporation. All rights reserved.
#  Licensed under the MIT License (MIT). See LICENSE in the repo root for license information.
#  ------------------------------------------------------------------------------------------
import torch
import torch.nn as nn

from typing import Dict

from .layers import LoRALayer


def mark_only_lora_as_trainable(model: nn.Module, bias: str = "none") -> None:
    for n, p in model.named_parameters():
        if "lora_" not in n and "cif" not in n:
            p.requires_grad = False
    if bias == "none":
        return
    elif bias == "all":
        for n, p in model.named_parameters():
            if "bias" in n:
                p.requires_grad = True
    elif bias == "lora_only":
        for m in model.modules():
            if isinstance(m, LoRALayer) and hasattr(m, "bias") and m.bias is not None:
                m.bias.requires_grad = True
    else:
        raise NotImplementedError


def lora_state_dict(model: nn.Module, bias: str = "none") -> Dict[str, torch.Tensor]:
    my_state_dict = model.state_dict()
    if bias == "none":
        return {k: my_state_dict[k] for k in my_state_dict if "lora_" in k}
    elif bias == "all":
        return {k: my_state_dict[k] for k in my_state_dict if "lora_" in k or "bias" in k}
    elif bias == "lora_only":
        to_return = {}
        for k in my_state_dict:
            if "lora_" in k:
                to_return[k] = my_state_dict[k]
                bias_name = k.split("lora_")[0] + "bias"
                if bias_name in my_state_dict:
                    to_return[bias_name] = my_state_dict[bias_name]
        return to_return
    else:
        raise NotImplementedError
