import os

import torch

from ..domain.model import Clip, Pipeline
from ..domain.repositories import PipelineRepository


class PipelineUsecase:
    def __init__(self, pipeline_repo: PipelineRepository) -> None:
        self.pipeline_repo = pipeline_repo
        self.dtype = torch.float32

    def execute(self, checkpoint_path: str) -> tuple[Pipeline, Clip]:
        if not os.path.exists(checkpoint_path):
            raise FileNotFoundError(f"Checkpoint file not found: {checkpoint_path}")

        path = self.pipeline_repo.convert_and_save_from_single_file(checkpoint_path, self.dtype)
        if not os.path.exists(path):
            raise RuntimeError(f"Failed to convert pipeline checkpoint: {checkpoint_path}")

        pipe = self.pipeline_repo.load_pipeline_from_path(path, self.dtype)
        if pipe is None:
            raise RuntimeError(f"Failed to create pipeline from checkpoint: {checkpoint_path}")

        pipeline = Pipeline(pipeline=pipe, path=path)
        clip = Clip(
            tokenizer=pipe.tokenizer,  # type: ignore[attr-defined]
            text_encoder=pipe.text_encoder,  # type: ignore[attr-defined]
            path=checkpoint_path,
        )

        return pipeline, clip