# Copyright (c) Meta Platforms, Inc. and affiliates.
#
# This software may be used and distributed in accordance with
# the terms of the DINOv3 License Agreement.

import os
from enum import Enum
from typing import List, Optional, Union
from urllib.parse import urlparse
from pathlib import Path

import torch

from .utils import DINOV3_BASE_URL


class Weights(Enum):
    LVD1689M = "LVD1689M"
    SAT493M = "SAT493M"


def is_url(path: str) -> bool:
    parsed = urlparse(path)
    return parsed.scheme in ("https", "file")


def convert_path_or_url_to_url(path: str) -> str:
    if is_url(path):
        return path
    return Path(path).expanduser().resolve().as_uri()


def _make_dinov3_vit_model_arch(
    *,
    patch_size: int = 16,
    compact_arch_name: str = "vitb",
):
    if "plus" in compact_arch_name:
        model_arch = compact_arch_name.replace("plus", f"{patch_size}plus")
    else:
        model_arch = f"{compact_arch_name}{patch_size}"
    return model_arch


def _make_dinov3_vit_model_url(
    *,
    patch_size: int = 16,
    compact_arch_name: str = "vitb",
    version: Optional[str] = None,
    weights: Union[Weights, str] = Weights.LVD1689M,
    hash: Optional[str] = None,
):
    model_name = "dinov3"
    model_arch = _make_dinov3_vit_model_arch(patch_size=patch_size, compact_arch_name=compact_arch_name)
    version_suffix = f"_{version}" if version else ""
    weights_name = weights.value.lower()
    hash_suffix = f"-{hash}" if hash else ""
    model_dir = f"{model_name}_{model_arch}"
    model_filename = f"{model_name}_{model_arch}_pretrain_{weights_name}{version_suffix}{hash_suffix}.pth"
    return os.path.join(DINOV3_BASE_URL, model_dir, model_filename)


def _make_dinov3_vit(
    *,
    img_size: int = 224,
    patch_size: int = 16,
    in_chans: int = 3,
    compact_arch_name: str = "vitb",
    pos_embed_rope_base: float = 100.0,
    pos_embed_rope_min_period: float | None = None,
    pos_embed_rope_max_period: float | None = None,
    pos_embed_rope_normalize_coords: str = "separate",
    pos_embed_rope_shift_coords: float | None = None,
    pos_embed_rope_jitter_coords: float | None = None,
    pos_embed_rope_rescale_coords: float | None = None,
    pos_embed_rope_dtype: str = "fp32",
    embed_dim: int = 768,
    depth: int = 12,
    num_heads: int = 12,
    ffn_ratio: float = 4.0,
    qkv_bias: bool = True,
    drop_path_rate: float = 0.0,
    layerscale_init: float | None = None,
    norm_layer: str = "layernorm",
    ffn_layer: str = "mlp",
    ffn_bias: bool = True,
    proj_bias: bool = True,
    n_storage_tokens: int = 0,
    mask_k_bias: bool = False,
    pretrained: bool = True,
    version: Optional[str] = None,
    weights: Union[Weights, str] = Weights.LVD1689M,
    hash: Optional[str] = None,
    check_hash: bool = False,
    **kwargs,
):
    from ..models.vision_transformer import DinoVisionTransformer

    vit_kwargs = dict(
        img_size=img_size,
        patch_size=patch_size,
        in_chans=in_chans,
        pos_embed_rope_base=pos_embed_rope_base,
        pos_embed_rope_min_period=pos_embed_rope_min_period,
        pos_embed_rope_max_period=pos_embed_rope_max_period,
        pos_embed_rope_normalize_coords=pos_embed_rope_normalize_coords,
        pos_embed_rope_shift_coords=pos_embed_rope_shift_coords,
        pos_embed_rope_jitter_coords=pos_embed_rope_jitter_coords,
        pos_embed_rope_rescale_coords=pos_embed_rope_rescale_coords,
        pos_embed_rope_dtype=pos_embed_rope_dtype,
        embed_dim=embed_dim,
        depth=depth,
        num_heads=num_heads,
        ffn_ratio=ffn_ratio,
        qkv_bias=qkv_bias,
        drop_path_rate=drop_path_rate,
        layerscale_init=layerscale_init,
        norm_layer=norm_layer,
        ffn_layer=ffn_layer,
        ffn_bias=ffn_bias,
        proj_bias=proj_bias,
        n_storage_tokens=n_storage_tokens,
        mask_k_bias=mask_k_bias,
    )
    vit_kwargs.update(**kwargs)
    model = DinoVisionTransformer(**vit_kwargs)
    if pretrained:
        if type(weights) is Weights and weights not in {Weights.LVD1689M, Weights.SAT493M}:
            raise ValueError(f"Unsupported weights for the backbone: {weights}")
        elif type(weights) is Weights:
            url = _make_dinov3_vit_model_url(
                patch_size=patch_size,
                compact_arch_name=compact_arch_name,
                version=version,
                weights=weights,
                hash=hash,
            )
        else:
            url = convert_path_or_url_to_url(weights)
        state_dict = torch.hub.load_state_dict_from_url(url, map_location="cpu", check_hash=check_hash)
        model.load_state_dict(state_dict, strict=True)
    else:
        model.init_weights()
    return model


def _make_dinov3_convnext_model_url(
    *,
    compact_arch_name: str = "convnext_base",
    weights: Union[Weights, str] = Weights.LVD1689M,
    hash: Optional[str] = None,
):
    model_name = "dinov3"
    weights_name = weights.value.lower()
    hash_suffix = f"-{hash}" if hash else ""

    model_dir = f"{model_name}_{compact_arch_name}"
    model_filename = f"{model_name}_{compact_arch_name}_pretrain_{weights_name}{hash_suffix}.pth"
    return os.path.join(DINOV3_BASE_URL, model_dir, model_filename)


def _make_dinov3_convnext(
    in_chans: int = 3,
    depths: List[int] = [3, 3, 27, 3],
    dims: List[int] = [128, 256, 512, 1024],
    compact_arch_name: str = "convnext_base",
    drop_path_rate: float = 0.0,
    layer_scale_init_value: float = 1e-6,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    hash: Optional[str] = None,
    **kwargs,
):
    from ..models.convnext import ConvNeXt

    model_kwargs = dict(
        in_chans=in_chans,
        depths=depths,
        dims=dims,
        drop_path_rate=drop_path_rate,
        layer_scale_init_value=layer_scale_init_value,
    )
    model_kwargs.update(**kwargs)
    model = ConvNeXt(**model_kwargs)
    if pretrained:
        if type(weights) is Weights and weights not in {Weights.LVD1689M, Weights.SAT493M}:
            raise ValueError(f"Unsupported weights for the backbone: {weights}")
        elif type(weights) is Weights:
            url = _make_dinov3_convnext_model_url(
                compact_arch_name=compact_arch_name,
                weights=weights,
                hash=hash,
            )
        else:
            url = convert_path_or_url_to_url(weights)
        state_dict = torch.hub.load_state_dict_from_url(url, map_location="cpu")
        model.load_state_dict(state_dict, strict=True)
    return model


def dinov3_vits16(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    check_hash: bool = False,
    **kwargs,
):
    if "hash" not in kwargs:
        kwargs["hash"] = "08c60483"
    kwargs["version"] = None
    return _make_dinov3_vit(
        img_size=224,
        patch_size=16,
        in_chans=3,
        pos_embed_rope_base=100,
        pos_embed_rope_normalize_coords="separate",
        pos_embed_rope_rescale_coords=2,
        pos_embed_rope_dtype="fp32",
        embed_dim=384,
        depth=12,
        num_heads=6,
        ffn_ratio=4,
        qkv_bias=True,
        drop_path_rate=0.0,
        layerscale_init=1.0e-05,
        norm_layer="layernormbf16",
        ffn_layer="mlp",
        ffn_bias=True,
        proj_bias=True,
        n_storage_tokens=4,
        mask_k_bias=True,
        pretrained=pretrained,
        weights=weights,
        compact_arch_name="vits",
        check_hash=check_hash,
        **kwargs,
    )


def dinov3_vits16plus(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    check_hash: bool = False,
    **kwargs,
):
    if "hash" not in kwargs:
        kwargs["hash"] = "4057cbaa"
    kwargs["version"] = None
    return _make_dinov3_vit(
        img_size=224,
        patch_size=16,
        in_chans=3,
        pos_embed_rope_base=100,
        pos_embed_rope_normalize_coords="separate",
        pos_embed_rope_rescale_coords=2,
        pos_embed_rope_dtype="fp32",
        embed_dim=384,
        depth=12,
        num_heads=6,
        ffn_ratio=6,
        qkv_bias=True,
        drop_path_rate=0.0,
        layerscale_init=1.0e-05,
        norm_layer="layernormbf16",
        ffn_layer="swiglu",
        ffn_bias=True,
        proj_bias=True,
        n_storage_tokens=4,
        mask_k_bias=True,
        pretrained=pretrained,
        weights=weights,
        compact_arch_name="vitsplus",
        check_hash=check_hash,
        **kwargs,
    )


def dinov3_vitb16(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    check_hash: bool = False,
    **kwargs,
):
    if "hash" not in kwargs:
        kwargs["hash"] = "73cec8be"
    kwargs["version"] = None
    return _make_dinov3_vit(
        img_size=224,
        patch_size=16,
        in_chans=3,
        pos_embed_rope_base=100,
        pos_embed_rope_normalize_coords="separate",
        pos_embed_rope_rescale_coords=2,
        pos_embed_rope_dtype="fp32",
        embed_dim=768,
        depth=12,
        num_heads=12,
        ffn_ratio=4,
        qkv_bias=True,
        drop_path_rate=0.0,
        layerscale_init=1.0e-05,
        norm_layer="layernormbf16",
        ffn_layer="mlp",
        ffn_bias=True,
        proj_bias=True,
        n_storage_tokens=4,
        mask_k_bias=True,
        pretrained=pretrained,
        weights=weights,
        compact_arch_name="vitb",
        check_hash=check_hash,
        **kwargs,
    )


def dinov3_vitl16(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    check_hash: bool = False,
    **kwargs,
):
    untie_global_and_local_cls_norm = False
    if weights == Weights.LVD1689M:
        if "hash" not in kwargs:
            kwargs["hash"] = "8aa4cbdd"
    elif weights == Weights.SAT493M:
        if "hash" not in kwargs:
            kwargs["hash"] = "eadcf0ff"
        untie_global_and_local_cls_norm = True
    elif type(weights) is str:
        import re

        pattern = r"-(.{8}).pth"
        matches = re.findall(pattern, weights)
        if len(matches) != 1:
            raise ValueError(f"Unexpected weights specification for the ViT-L backbone: {weights}")
        hash = matches[0]
        if hash == "eadcf0ff":
            untie_global_and_local_cls_norm = True
    kwargs["version"] = None
    return _make_dinov3_vit(
        img_size=224,
        patch_size=16,
        in_chans=3,
        pos_embed_rope_base=100,
        pos_embed_rope_normalize_coords="separate",
        pos_embed_rope_rescale_coords=2,
        pos_embed_rope_dtype="fp32",
        embed_dim=1024,
        depth=24,
        num_heads=16,
        ffn_ratio=4,
        qkv_bias=True,
        drop_path_rate=0.0,
        layerscale_init=1.0e-05,
        norm_layer="layernormbf16",
        ffn_layer="mlp",
        ffn_bias=True,
        proj_bias=True,
        n_storage_tokens=4,
        mask_k_bias=True,
        untie_global_and_local_cls_norm=untie_global_and_local_cls_norm,
        pretrained=pretrained,
        weights=weights,
        compact_arch_name="vitl",
        check_hash=check_hash,
        **kwargs,
    )


def dinov3_vitl16plus(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    check_hash: bool = False,
    **kwargs,
):
    if "hash" not in kwargs:
        kwargs["hash"] = "46503df0"

    return _make_dinov3_vit(
        img_size=224,
        patch_size=16,
        in_chans=3,
        pos_embed_rope_base=100,
        pos_embed_rope_normalize_coords="separate",
        pos_embed_rope_rescale_coords=2,
        pos_embed_rope_dtype="fp32",
        embed_dim=1024,
        depth=24,
        num_heads=16,
        ffn_ratio=6.0,
        qkv_bias=True,
        drop_path_rate=0.0,
        layerscale_init=1.0e-05,
        norm_layer="layernormbf16",
        ffn_layer="swiglu",
        ffn_bias=True,
        proj_bias=True,
        n_storage_tokens=4,
        mask_k_bias=True,
        pretrained=pretrained,
        weights=weights,
        compact_arch_name="vitlplus",
        check_hash=check_hash,
        **kwargs,
    )


def dinov3_vith16plus(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    check_hash: bool = False,
    **kwargs,
):
    if "hash" not in kwargs:
        kwargs["hash"] = "7c1da9a5"

    return _make_dinov3_vit(
        img_size=224,
        patch_size=16,
        in_chans=3,
        pos_embed_rope_base=100,
        pos_embed_rope_normalize_coords="separate",
        pos_embed_rope_rescale_coords=2,
        pos_embed_rope_dtype="fp32",
        embed_dim=1280,
        depth=32,
        num_heads=20,
        ffn_ratio=6.0,
        qkv_bias=True,
        drop_path_rate=0.0,
        layerscale_init=1.0e-05,
        norm_layer="layernormbf16",
        ffn_layer="swiglu",
        ffn_bias=True,
        proj_bias=True,
        n_storage_tokens=4,
        mask_k_bias=True,
        pretrained=pretrained,
        weights=weights,
        compact_arch_name="vithplus",
        check_hash=check_hash,
        **kwargs,
    )


def dinov3_vit7b16(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    check_hash: bool = False,
    **kwargs,
):
    if weights == Weights.LVD1689M:
        if "hash" not in kwargs:
            kwargs["hash"] = "a955f4ea"
    elif weights == Weights.SAT493M:
        if "hash" not in kwargs:
            kwargs["hash"] = "a6675841"
    kwargs["version"] = None
    untie_global_and_local_cls_norm = True
    return _make_dinov3_vit(
        img_size=224,
        patch_size=16,
        in_chans=3,
        pos_embed_rope_base=100,
        pos_embed_rope_normalize_coords="separate",
        pos_embed_rope_rescale_coords=2,
        pos_embed_rope_dtype="fp32",
        embed_dim=4096,
        depth=40,
        num_heads=32,
        ffn_ratio=3,
        qkv_bias=False,
        drop_path_rate=0.4,
        layerscale_init=1.0e-05,
        norm_layer="layernormbf16",
        ffn_layer="swiglu64",
        ffn_bias=True,
        proj_bias=True,
        n_storage_tokens=4,
        mask_k_bias=True,
        untie_global_and_local_cls_norm=untie_global_and_local_cls_norm,
        pretrained=pretrained,
        weights=weights,
        compact_arch_name="vit7b",
        check_hash=check_hash,
        **kwargs,
    )


def dinov3_convnext_tiny(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    **kwargs,
):
    _hash_convnext = "21b726bb"
    if "hash" not in kwargs:
        kwargs["hash"] = _hash_convnext

    from ..models.convnext import convnext_sizes

    size_dict = convnext_sizes["tiny"]

    model = _make_dinov3_convnext(
        in_chans=3,
        depths=size_dict["depths"],
        dims=size_dict["dims"],
        compact_arch_name="convnext_tiny",
        drop_path_rate=0,
        layer_scale_init_value=1e-6,
        pretrained=pretrained,
        weights=weights,
        **kwargs,
    )
    if not pretrained:
        model.init_weights()
    return model


def dinov3_convnext_small(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    **kwargs,
):
    _hash_convnext = "296db49d"
    if "hash" not in kwargs:
        kwargs["hash"] = _hash_convnext

    from ..models.convnext import convnext_sizes

    size_dict = convnext_sizes["small"]

    model = _make_dinov3_convnext(
        in_chans=3,
        depths=size_dict["depths"],
        dims=size_dict["dims"],
        compact_arch_name="convnext_small",
        drop_path_rate=0,
        layer_scale_init_value=1e-6,
        pretrained=pretrained,
        weights=weights,
        **kwargs,
    )
    if not pretrained:
        model.init_weights()
    return model


def dinov3_convnext_base(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    **kwargs,
):
    _hash_convnext = "801f2ba9"
    if "hash" not in kwargs:
        kwargs["hash"] = _hash_convnext

    from ..models.convnext import convnext_sizes

    size_dict = convnext_sizes["base"]

    model = _make_dinov3_convnext(
        in_chans=3,
        depths=size_dict["depths"],
        dims=size_dict["dims"],
        compact_arch_name="convnext_base",
        drop_path_rate=0,
        layer_scale_init_value=1e-6,
        pretrained=pretrained,
        weights=weights,
        **kwargs,
    )
    if not pretrained:
        model.init_weights()
    return model


def dinov3_convnext_large(
    *,
    pretrained: bool = True,
    weights: Union[Weights, str] = Weights.LVD1689M,
    **kwargs,
):
    _hash_convnext = "61fa432d"
    if "hash" not in kwargs:
        kwargs["hash"] = _hash_convnext

    from ..models.convnext import convnext_sizes

    size_dict = convnext_sizes["large"]

    model = _make_dinov3_convnext(
        in_chans=3,
        depths=size_dict["depths"],
        dims=size_dict["dims"],
        compact_arch_name="convnext_large",
        drop_path_rate=0,
        layer_scale_init_value=1e-6,
        pretrained=pretrained,
        weights=weights,
        **kwargs,
    )
    if not pretrained:
        model.init_weights()
    return model