import os
import unittest

from fastNLP.core.dataset import DataSet
from fastNLP.core.field import TextField
from fastNLP.core.instance import Instance
from fastNLP.core.loss import Loss
from fastNLP.core.optimizer import Optimizer
from fastNLP.core.trainer import SeqLabelTrainer
from fastNLP.models.sequence_modeling import SeqLabeling


class TestTrainer(unittest.TestCase):
    def test_case_1(self):
        args = {"epochs": 3, "batch_size": 2, "validate": True, "use_cuda": False, "pickle_path": "./save/",
                "save_best_dev": True, "model_name": "default_model_name.pkl",
                "loss": Loss(None),
                "optimizer": Optimizer("Adam", lr=0.001, weight_decay=0),
                "vocab_size": 10,
                "word_emb_dim": 100,
                "rnn_hidden_units": 100,
                "num_classes": 5
                }
        trainer = SeqLabelTrainer(**args)

        train_data = [
            [['a', 'b', 'c', 'd', 'e'], ['a', '@', 'c', 'd', 'e']],
            [['a', '@', 'c', 'd', 'e'], ['a', '@', 'c', 'd', 'e']],
            [['a', 'b', '#', 'd', 'e'], ['a', '@', 'c', 'd', 'e']],
            [['a', 'b', 'c', '?', 'e'], ['a', '@', 'c', 'd', 'e']],
            [['a', 'b', 'c', 'd', '$'], ['a', '@', 'c', 'd', 'e']],
            [['!', 'b', 'c', 'd', 'e'], ['a', '@', 'c', 'd', 'e']],
        ]
        vocab = {'a': 0, 'b': 1, 'c': 2, 'd': 3, 'e': 4, '!': 5, '@': 6, '#': 7, '$': 8, '?': 9}
        label_vocab = {'a': 0, '@': 1, 'c': 2, 'd': 3, 'e': 4}

        data_set = DataSet()
        for example in train_data:
            text, label = example[0], example[1]
            x = TextField(text, False)
            y = TextField(label, is_target=True)
            ins = Instance(word_seq=x, label_seq=y)
            data_set.append(ins)

        data_set.index_field("word_seq", vocab)
        data_set.index_field("label_seq", label_vocab)

        model = SeqLabeling(args)

        trainer.train(network=model, train_data=data_set, dev_data=data_set)
        # If this can run, everything is OK.

        os.system("rm -rf save")
        print("pickle path deleted")