import typing as tp
from collections import namedtuple

import torch

from transformers import Pipeline, AutoModelForSequenceClassification
from transformers.pipelines import PIPELINE_REGISTRY


class PapersClassificationPipeline(Pipeline):
    def _sanitize_parameters(self, **kwargs):
        return {}, {}, {}

    def preprocess(self, inputs):
        if (
            not isinstance(inputs, tp.Iterable)
            or isinstance(inputs, tp.Dict)
            or isinstance(inputs, str)
        ):
            inputs = [inputs]
        title = "title"
        authors = "authors"
        abstract = "abstract"
        texts = [
            (
                f"AUTHORS: {' '.join(paper[title]) if isinstance(paper[authors], list) else paper[authors]} "
                f"TITLE: {paper[title]} ABSTRACT: {paper[abstract]}"
                if not isinstance(paper, str)
                else paper
            )
            for paper in inputs
        ]
        inputs = self.tokenizer(
            texts, truncation=True, padding=True, max_length=256, return_tensors="pt"
        ).to(self.device)
        return inputs

    def _forward(self, model_inputs):
        with torch.no_grad():
            outputs = self.model(**model_inputs)
        return outputs

    def postprocess(self, model_outputs):
        probs = torch.nn.functional.softmax(model_outputs.logits, dim=-1)
        results = []
        for prob in probs:
            result = [
                {"label": self.model.config.id2label[label_idx], "score": score.item()}
                for label_idx, score in enumerate(prob)
            ]
            results.append(result)
        if 1 == len(results):
            return results[0]
        return results


PIPELINE_REGISTRY.register_pipeline(
    "paper-classification",
    pipeline_class=PapersClassificationPipeline,
    pt_model=AutoModelForSequenceClassification,
)