#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

# $example on$
from pyspark.ml.classification import LogisticRegression
# $example off$
from pyspark.sql import SparkSession

if __name__ == "__main__":
    spark = SparkSession \
        .builder \
        .appName("MulticlassLogisticRegressionWithElasticNet") \
        .getOrCreate()

    # $example on$
    # Load training data
    training = spark \
        .read \
        .format("libsvm") \
        .load("data/mllib/sample_multiclass_classification_data.txt")

    lr = LogisticRegression(maxIter=10, regParam=0.3, elasticNetParam=0.8)

    # Fit the model
    lrModel = lr.fit(training)

    # Print the coefficients and intercept for multinomial logistic regression
    print("Coefficients: \n" + str(lrModel.coefficientMatrix))
    print("Intercept: " + str(lrModel.interceptVector))

    trainingSummary = lrModel.summary

    # Obtain the objective per iteration
    objectiveHistory = trainingSummary.objectiveHistory
    print("objectiveHistory:")
    for objective in objectiveHistory:
        print(objective)

    # for multiclass, we can inspect metrics on a per-label basis
    print("False positive rate by label:")
    for i, rate in enumerate(trainingSummary.falsePositiveRateByLabel):
        print("label %d: %s" % (i, rate))

    print("True positive rate by label:")
    for i, rate in enumerate(trainingSummary.truePositiveRateByLabel):
        print("label %d: %s" % (i, rate))

    print("Precision by label:")
    for i, prec in enumerate(trainingSummary.precisionByLabel):
        print("label %d: %s" % (i, prec))

    print("Recall by label:")
    for i, rec in enumerate(trainingSummary.recallByLabel):
        print("label %d: %s" % (i, rec))

    print("F-measure by label:")
    for i, f in enumerate(trainingSummary.fMeasureByLabel()):
        print("label %d: %s" % (i, f))

    accuracy = trainingSummary.accuracy
    falsePositiveRate = trainingSummary.weightedFalsePositiveRate
    truePositiveRate = trainingSummary.weightedTruePositiveRate
    fMeasure = trainingSummary.weightedFMeasure()
    precision = trainingSummary.weightedPrecision
    recall = trainingSummary.weightedRecall
    print("Accuracy: %s\nFPR: %s\nTPR: %s\nF-measure: %s\nPrecision: %s\nRecall: %s"
          % (accuracy, falsePositiveRate, truePositiveRate, fMeasure, precision, recall))
    # $example off$

    spark.stop()
