from sklearn.feature_extraction.text import TfidfVectorizer
from sklearn.linear_model import LinearRegression
import pickle

filename = 'regressor.sav'
vec_file = 'vectorizer.pickle'
regressor = LinearRegression()
# regressor = pickle.load(open(filename, 'rb'))
vectorizer = TfidfVectorizer()
# vectorizer = pickle.load(open(vec_file, 'rb'))


def train():
    with open('train/train.tsv') as f:
        docs = [line.rstrip() for line in f]
    docs_preprocessed = []
    y = []
    for doc in docs:
        row = doc.split('\t')
        start_date = row[0]
        end_date = row[1]
        end_date = end_date.split(' ')
        if len(end_date) > 1:
            row.insert(4, end_date[1])
        end_date = end_date[0]
        doc = row[4:5][0]
        docs_preprocessed.append(doc)
        y.append((float(start_date) + float(end_date))/2)
    y = [float(value) for value in y]
    print('Fitting vectorizer...')
    x = vectorizer.fit_transform(docs_preprocessed)
    pickle.dump(vectorizer, open(vec_file, 'wb'))
    print('DONE!')
    print('Fitting regressor...')
    regressor.fit(x, y)
    pickle.dump(regressor, open(filename, 'wb'))
    print('DONE!')


def classify(path):
    print("Predicting for", path)
    with open(path + 'in.tsv') as f:
        docs = [line.rstrip() for line in f]
    test_x = vectorizer.transform(docs)
    predictions = regressor.predict(test_x)
    with open(path + 'out.tsv', 'w') as file:
        for prediction in predictions:
            file.write("%f\n" % prediction)


train()
classify('dev-0/')
# classify('dev-1/')
# classify('test-A/')