import json
import os
from pathlib import Path
from typing import Any, Dict, List, Union

import boto3
import torch
from lora_diffusion import patch_pipe, tune_lora_scale
from pydash import chain

from internals.data.dataAccessor import getStyles
from internals.util.commons import download_file


class LoraStyle:
    class LoraPatcher:
        def __init__(self, pipe, style: Dict[str, Any]):
            self.__style = style
            self.pipe = pipe

        @torch.inference_mode()
        def patch(self):
            path = self.__style["path"]
            if str(path).endswith((".pt", ".safetensors")):
                patch_pipe(self.pipe, self.__style["path"])
                tune_lora_scale(self.pipe.unet, self.__style["weight"])
                tune_lora_scale(self.pipe.text_encoder, self.__style["weight"])

        def kwargs(self):
            return {}

        def cleanup(self):
            tune_lora_scale(self.pipe.unet, 0.0)
            tune_lora_scale(self.pipe.text_encoder, 0.0)
            pass

    class EmptyLoraPatcher:
        def __init__(self, pipe):
            self.pipe = pipe

        def patch(self):
            "Patch will act as cleanup, to tune down any corrupted lora"
            self.cleanup()
            pass

        def kwargs(self):
            return {}

        def cleanup(self):
            tune_lora_scale(self.pipe.unet, 0.0)
            tune_lora_scale(self.pipe.text_encoder, 0.0)
            pass

    def load(self, model_dir: str):
        self.model = model_dir
        self.fetch_styles()

    def fetch_styles(self):
        model_dir = self.model
        result = getStyles()
        if result is not None:
            self.__styles = self.__parse_styles(model_dir, result["data"])
        else:
            self.__styles = self.__get_default_styles(model_dir)
        self.__verify()

    def prepend_style_to_prompt(self, prompt: str, key: str) -> str:
        if key in self.__styles:
            style = self.__styles[key]
            return f"{', '.join(style['text'])}, {prompt}"
        return prompt

    def get_patcher(self, pipe, key: str) -> Union[LoraPatcher, EmptyLoraPatcher]:
        if key in self.__styles:
            style = self.__styles[key]
            return self.LoraPatcher(pipe, style)
        return self.EmptyLoraPatcher(pipe)

    def __parse_styles(self, model_dir: str, data: List[Dict]) -> Dict:
        styles = {}
        download_dir = Path(Path.home() / ".cache" / "lora")
        download_dir.mkdir(exist_ok=True)
        data = chain(data).uniq_by(lambda x: x["tag"]).value()
        for item in data:
            if item["attributes"] is not None:
                attr = json.loads(item["attributes"])
                if "path" in attr:
                    file_path = Path(download_dir / attr["path"].split("/")[-1])

                    if not file_path.exists():
                        s3_uri = attr["path"]
                        download_file(s3_uri, file_path)

                    styles[item["tag"]] = {
                        "path": str(file_path),
                        "weight": attr["weight"],
                        "type": attr["type"],
                        "text": attr["text"],
                        "negativePrompt": attr["negativePrompt"],
                    }
        if len(styles) == 0:
            return self.__get_default_styles(model_dir)
        return styles

    def __get_default_styles(self, model_dir: str) -> Dict:
        return {
            "nq6akX1CIp": {
                "path": model_dir + "/laur_style/nq6akX1CIp/final_lora.safetensors",
                "text": ["nq6akX1CIp style"],
                "weight": 0.5,
                "negativePrompt": [""],
                "type": "custom",
            },
            "ghibli": {
                "path": model_dir + "/laur_style/nq6akX1CIp/ghibli.bin",
                "text": ["ghibli style"],
                "weight": 1,
                "negativePrompt": [""],
                "type": "custom",
            },
            "eQAmnK2kB2": {
                "path": model_dir + "/laur_style/eQAmnK2kB2/final_lora.safetensors",
                "text": ["eQAmnK2kB2 style"],
                "weight": 0.5,
                "negativePrompt": [""],
                "type": "custom",
            },
            "to8contrast": {
                "path": model_dir + "/laur_style/rpjgusOgqD/final_lora.bin",
                "text": ["to8contrast style"],
                "weight": 0.5,
                "negativePrompt": [""],
                "type": "custom",
            },
            "sfrrfz8vge": {
                "path": model_dir + "/laur_style/replicate/sfrrfz8vge.safetensors",
                "text": ["sfrrfz8vge style"],
                "weight": 1.2,
                "negativePrompt": [""],
                "type": "custom",
            },
        }

    def __verify(self):
        "A method to verify if lora exists within the required path otherwise throw error"

        for item in self.__styles.keys():
            if not os.path.exists(self.__styles[item]["path"]):
                raise Exception(
                    "Lora style model "
                    + item
                    + " not found at path: "
                    + self.__styles[item]["path"]
                )