# -*- coding: utf-8 -*-

import argparse
import os

import numpy as np
import tensorflow as tf

import nsml
from nsml import DATASET_PATH, HAS_DATASET, IS_ON_NSML
from dataset import MovieReviewDataset, preprocess


# DONOTCHANGE: They are reserved for nsml
# This is for nsml leaderboard
def bind_model(sess, config):
    # 학습한 모델을 저장하는 함수입니다.
    def save(dir_name, *args):
        # directory
        os.makedirs(dir_name, exist_ok=True)
        saver = tf.train.Saver()
        saver.save(sess, os.path.join(dir_name, 'model'))

    # 저장한 모델을 불러올 수 있는 함수입니다.
    def load(dir_name, *args):
        saver = tf.train.Saver()
        # find checkpoint
        ckpt = tf.train.get_checkpoint_state(dir_name)
        if ckpt and ckpt.model_checkpoint_path:
            checkpoint = os.path.basename(ckpt.model_checkpoint_path)
            saver.restore(sess, os.path.join(dir_name, checkpoint))
        else:
            raise NotImplemented('No checkpoint!')
        print('Model loaded')

    def infer(raw_data, **kwargs):
        """
        :param raw_data: raw input (여기서는 문자열)을 입력받습니다
        :param kwargs:
        :return:
        """
        # dataset.py에서 작성한 preprocess 함수를 호출하여, 문자열을 벡터로 변환합니다
        preprocessed_data = preprocess(raw_data, config.strmaxlen)
        # 저장한 모델에 입력값을 넣고 prediction 결과를 리턴받습니다
        pred = sess.run(output_sigmoid, feed_dict={x: preprocessed_data})
        clipped = np.array(pred > config.threshold, dtype=np.int)
        # DONOTCHANGE: They are reserved for nsml
        # 리턴 결과는 [(확률, 0 or 1)] 의 형태로 보내야만 리더보드에 올릴 수 있습니다. 리더보드 결과에 확률의 값은 영향을 미치지 않습니다
        return list(zip(pred.flatten(), clipped.flatten()))

    # DONOTCHANGE: They are reserved for nsml
    # nsml에서 지정한 함수에 접근할 수 있도록 하는 함수입니다.
    nsml.bind(save=save, load=load, infer=infer)


def _batch_loader(iterable, n=1):
    """
    데이터를 배치 사이즈만큼 잘라서 보내주는 함수입니다. PyTorch의 DataLoader와 같은 역할을 합니다
    :param iterable: 데이터 list, 혹은 다른 포맷
    :param n: 배치 사이즈
    :return:
    """
    length = len(iterable)
    for n_idx in range(0, length, n):
        yield iterable[n_idx:min(n_idx + n, length)]


def weight_variable(shape):
    initial = tf.truncated_normal(shape, stddev=0.1)
    return tf.Variable(initial)


def bias_variable(shape):
    initial = tf.constant(0.1, shape=shape)
    return tf.Variable(initial)


if __name__ == '__main__':
    args = argparse.ArgumentParser()
    # DONOTCHANGE: They are reserved for nsml
    args.add_argument('--mode', type=str, default='train')
    args.add_argument('--pause', type=int, default=0)
    args.add_argument('--iteration', type=str, default='0')

    # User options
    args.add_argument('--output', type=int, default=1)
    args.add_argument('--epochs', type=int, default=10)
    args.add_argument('--batch', type=int, default=3000)
    args.add_argument('--strmaxlen', type=int, default=300)
    args.add_argument('--embedding', type=int, default=50)
    args.add_argument('--threshold', type=float, default=0.5)
    config = args.parse_args()

    if not HAS_DATASET and not IS_ON_NSML:  # It is not running on nsml
        DATASET_PATH = '../sample_data/movie/'

    # 모델의 specification
    input_size = config.embedding*config.strmaxlen
    output_size = 1
    learning_rate = 0.001
    character_size = 251

    x = tf.placeholder(tf.int32, [None, config.strmaxlen])
    y_ = tf.placeholder(tf.float32, [None, output_size])
    keep_probs = tf.placeholder(tf.float32)
    # 임베딩
    char_embedding = tf.get_variable('char_embedding', [character_size, config.embedding])
    embedded_chars_base = tf.nn.embedding_lookup(char_embedding, x)
    embedded = tf.expand_dims(embedded_chars_base, -1)
    print("emb", embedded.shape)
    
    # MODEL
    l2_conv = tf.layers.conv2d(embedded, 256, [2, config.embedding], activation=tf.nn.relu)
    print("l2", l2_conv.shape)
    l2_pool = tf.layers.max_pooling2d(l2_conv, [character_size-2+1, 1], strides=(1,1))
    print("l2 pool", l2_pool.shape)

    l3_conv = tf.layers.conv2d(embedded, 256, [3, config.embedding], activation=tf.nn.relu)
    print("l3", l3_conv.shape)
    l3_pool = tf.layers.max_pooling2d(l3_conv, [character_size-3+1, 1], strides=(1,1))
    print("l3 pool", l3_pool.shape)

    concat = tf.concat([l2_pool, l3_pool], 3)
    print('concat', concat.shape)
    flatten = tf.contrib.layers.flatten(concat)
    print('flattne', flatten.shape)

    dense = tf.layers.dense(flatten, 256, activation=tf.nn.relu)

    drop = tf.layers.dropout(dense, keep_probs)
    output_sigmoid = 10*tf.layers.dense(drop, output_size, activation=tf.nn.sigmoid)


    # loss와 optimizer
    binary_cross_entropy = -tf.reduce_sum(y_*tf.log(tf.clip_by_value(tf.nn.log_softmax(output_sigmoid),1e-10,1.0)))
    train_step = tf.train.AdamOptimizer(learning_rate).minimize(binary_cross_entropy)

    sess = tf.InteractiveSession()
    tf.global_variables_initializer().run()

    # DONOTCHANGE: Reserved for nsml
    bind_model(sess=sess, config=config)

    # DONOTCHANGE: Reserved for nsml
    if config.pause:
        nsml.paused(scope=locals())

    if config.mode == 'train':
        # 데이터를 로드합니다.
        dataset = MovieReviewDataset(DATASET_PATH, config.strmaxlen)
        dataset_len = len(dataset)
        one_batch_size = dataset_len//config.batch
        if dataset_len % config.batch != 0:
            one_batch_size += 1
        # epoch마다 학습을 수행합니다.
        for epoch in range(config.epochs):
            avg_loss = 0.0
            for i, (data, labels) in enumerate(_batch_loader(dataset, config.batch)):
                _, loss = sess.run([train_step, binary_cross_entropy],
                                   feed_dict={x: data, y_: labels, keep_probs: 1.})
                print('Batch : ', i + 1, '/', one_batch_size,
                      ', BCE in this minibatch: ', float(loss))
                avg_loss += float(loss)
            print('epoch:', epoch, ' train_loss:', float(avg_loss/one_batch_size))
            nsml.report(summary=True, scope=locals(), epoch=epoch, epoch_total=config.epochs,
                        train__loss=float(avg_loss/one_batch_size), step=epoch)
            # DONOTCHANGE (You can decide how often you want to save the model)
            nsml.save(epoch)

    # 로컬 테스트 모드일때 사용합니다
    # 결과가 아래와 같이 나온다면, nsml submit을 통해서 제출할 수 있습니다.
    # [(0.3, 0), (0.7, 1), ... ]
    elif config.mode == 'test_local':
        with open(os.path.join(DATASET_PATH, 'train/train_data'), 'rt', encoding='utf-8') as f:
            queries = f.readlines()
        res = []
        for batch in _batch_loader(queries, config.batch):
            temp_res = nsml.infer(batch)
            res += temp_res
        print(res)