"""
Use a decisiontree classifier to predict flowers based on sepal and petal features

- This is an example of a supervised ML algorithm
    - it has labels on the training data
    - you tell the model: this is class X during training
"""

import matplotlib.pyplot as plt

from sklearn import datasets
from sklearn.tree import DecisionTreeClassifier
from sklearn import tree

# load the iris data set and look at its dimensions
iris = datasets.load_iris()
print(iris.data.size)
print(iris.target.size)
print(iris.feature_names)
print(iris.target_names)

# use a decision tree classifier
classifier = DecisionTreeClassifier()
# use all but the last sample for training
classifier.fit(iris.data[:-1], iris.target[:-1])

# use the model to predict the last data sample
last_sample = iris.data[-1:]
last_target = iris.target[-1:]
print(f"predicted: {last_sample} vs real: {last_target}")

# print the tree for visual inspection
fig, ax = plt.subplots(figsize=(20, 10))
tree.plot_tree(
    classifier,
    feature_names=iris.feature_names,
    class_names=iris.target_names,
    filled=True,
    rounded=True,
    ax=ax,
)
fig.savefig("decisiontree_iris.png", dpi=150, bbox_inches="tight")