import streamlit as st

# Introduction to Machine Learning
def introduction_to_ml():
    introduction_blog = '''
    ## 🤖 Introduction to Machine Learning (ML)
    Machine Learning (ML) is a subset of Artificial Intelligence (AI) that enables computers to learn from data and make predictions or decisions without being explicitly programmed. It has revolutionized many industries and plays a crucial role in technologies such as self-driving cars 🚗, recommendation systems 📱, and facial recognition 👁️.

    ### 🌍 Types of Machine Learning
    There are three main types of machine learning:

    1. **🔖 Supervised Learning**: 
        Supervised learning algorithms learn from labeled data. The model is trained using a dataset where the input data and the correct output are both provided. The goal is to learn a mapping from inputs to outputs. Examples include linear regression 📈, logistic regression 🧑‍💻, and decision trees 🌳.

    2. **🌌 Unsupervised Learning**: 
        In unsupervised learning, the algorithm is given data without any labeled outputs. The goal is to find hidden patterns or groupings in the data. Examples include clustering 🧠 (e.g., K-means) and dimensionality reduction techniques 🏗️ (e.g., PCA).

    3. **🏅 Reinforcement Learning**: 
        Reinforcement learning involves an agent that learns to make decisions by interacting with an environment to maximize a cumulative reward. It is widely used in robotics 🤖, game AI 🎮, and real-time decision-making systems.

    ### 🚀 Popular Machine Learning Algorithms
    Some of the most commonly used ML algorithms include:

    - **📉 Linear Regression**: A simple algorithm used for predicting continuous values.
    - **🔐 Logistic Regression**: Used for binary classification problems.
    - **🌳 Decision Trees**: A tree-like model used for both classification and regression tasks.
    - **🔍 K-Nearest Neighbors (KNN)**: A non-parametric method used for classification and regression.
    - **⚡ Support Vector Machines (SVM)**: A powerful classifier that works well for high-dimensional spaces.
    - **🧠 Neural Networks**: A set of algorithms, modeled after the human brain, that are used for complex tasks like image and speech recognition.

    #### 🌍 Applications of Machine Learning
    Machine learning is used in a wide variety of fields, including:

    - **🏥 Healthcare**: ML is used for predicting diseases, recommending treatments, and analyzing medical data.
    - **💰 Finance**: Used for fraud detection, algorithmic trading, and risk analysis.
    - **🛍️ E-commerce**: ML powers recommendation systems, personalized marketing, and customer support chatbots.
    - **🚘 Self-driving Cars**: ML algorithms help autonomous vehicles navigate and make real-time decisions.

    ### 🔚 Conclusion
    Machine learning continues to evolve, with new algorithms, techniques, and applications emerging regularly. As the amount of data grows 📊 and computational power increases ⚡, the potential of ML to impact industries and improve our daily lives is limitless.
    '''
    
    return introduction_blog

# Supervised Learning
def supervised_learning():
    supervised = '''
    ### 🔖 Supervised Learning
    Supervised learning algorithms learn from labeled data. The model is trained using a dataset where the input data and the correct output are both provided. The goal is to learn a mapping from inputs to outputs.
    
    **📚 Example**: 
    - **📈 Linear Regression**: Used to predict a continuous value, such as predicting house prices 🏠.
    ```python
    from sklearn.linear_model import LinearRegression
    X = [[1], [2], [3], [4], [5]]  # Features
    y = [1, 2, 2.5, 4, 5]  # Target
    model = LinearRegression()
    model.fit(X, y)
    predictions = model.predict([[6]])  # Predict for 6 hours of study 📚
    ```
    '''
    return supervised

# Unsupervised Learning
def unsupervised_learning():
    unsupervised = '''
    ### 🌌 Unsupervised Learning
    In unsupervised learning, the algorithm is given data without any labeled outputs. The goal is to find hidden patterns or groupings in the data. Examples include clustering 🧠 (e.g., K-means) and dimensionality reduction techniques 🏗️ (e.g., PCA).
    
    **📚 Example**:
    - **🔄 K-Means Clustering**: Grouping data points into clusters based on similarity.
    ```python
    from sklearn.cluster import KMeans
    X = [[1, 2], [1.5, 1.8], [5, 8], [8, 8], [1, 0.6], [9, 11]]
    kmeans = KMeans(n_clusters=2)
    kmeans.fit(X)
    labels = kmeans.predict(X)
    ```
    '''
    return unsupervised

# Reinforcement Learning
def reinforcement_learning():
    reinforcement = '''
    ### 🏅 Reinforcement Learning
    Reinforcement learning involves an agent that learns to make decisions by interacting with an environment to maximize a cumulative reward. It is widely used in robotics 🤖, game AI 🎮, and real-time decision-making systems.
    
    **📚 Example**: 
    - **🔄 Q-Learning**: A reinforcement learning algorithm where an agent learns to maximize rewards by updating Q-values.
    ```python
    import numpy as np
    Q = np.zeros((5, 5))  # Example Q-table for 5 states and 5 actions
    alpha = 0.1  # Learning rate
    gamma = 0.9  # Discount factor
    reward = 10
    state = 0
    action = 1
    next_state = 1
    Q[state, action] = Q[state, action] + alpha * (reward + gamma * np.max(Q[next_state]) - Q[state, action])
    ```
    '''
    return reinforcement

# Linear Regression
def linear_regression():
    linear = '''
    ### 📉 Linear Regression
    Linear regression is used to predict a continuous value based on one or more input features. It finds the best-fit line to minimize the error between the predicted and actual values.

    **📚 Example**: 
    - **🏠 Predicting House Prices**: Predict the price of a house based on its features such as size and location.
    ```python
    from sklearn.linear_model import LinearRegression
    X = [[1], [2], [3], [4], [5]]  # Features (e.g., years of experience)
    y = [1, 2, 2.5, 4, 5]  # Target (e.g., salary)
    model = LinearRegression()
    model.fit(X, y)
    predictions = model.predict([[6]])  # Predict for 6 years of experience
    ```
    '''
    return linear

# Logistic Regression
def logistic_regression():
    logistic = '''
    ### 🔐 Logistic Regression
    Logistic regression is used for binary classification tasks, where the goal is to predict one of two outcomes, such as pass/fail or spam/not spam.

    **📚 Example**:
    - **📧 Predicting Spam Emails**: Classifying emails as spam or not spam.
    ```python
    from sklearn.linear_model import LogisticRegression
    from sklearn.datasets import load_iris
    data = load_iris()
    X = data.data
    y = (data.target == 0).astype(int)  # Binary classification (class 0 vs others)
    model = LogisticRegression()
    model.fit(X, y)
    predictions = model.predict(X)
    ```
    '''
    return logistic

# Decision Trees
def decision_trees():
    decision = '''
    ### 🌳 Decision Trees
    Decision trees split the data into subsets based on feature values, creating a tree-like model. It is used for both classification and regression tasks.

    **📚 Example**:
    - **🌸 Classifying Iris Species**: A decision tree can be used to classify different species of Iris flowers.
    ```python
    from sklearn.tree import DecisionTreeClassifier
    from sklearn.datasets import load_iris
    data = load_iris()
    X = data.data
    y = data.target
    model = DecisionTreeClassifier()
    model.fit(X, y)
    predictions = model.predict(X)
    ```
    '''
    return decision

# K-Nearest Neighbors (KNN)
def knn():
    knn = '''
    ### 🔍 K-Nearest Neighbors (KNN)
    KNN is a simple, non-parametric algorithm that classifies data based on the majority vote of its nearest neighbors.

    **📚 Example**:
    - **📊 Classifying a Data Point**: Predict the class of a data point based on its nearest neighbors.
    ```python
    from sklearn.neighbors import KNeighborsClassifier
    from sklearn.datasets import load_iris
    data = load_iris()
    X = data.data
    y = data.target
    model = KNeighborsClassifier(n_neighbors=3)
    model.fit(X, y)
    predictions = model.predict(X)
    ```
    '''
    return knn

# Support Vector Machines (SVM)
def svm():
    svm = '''
    ### ⚡ Support Vector Machines (SVM)
    SVM is a powerful classifier that works well for high-dimensional data. It tries to find the hyperplane that best separates the data points of different classes.

    **📚 Example**:
    - **🌸 Classifying Iris Flowers**: An SVM can be used to classify Iris flowers into different species.
    ```python
    from sklearn.svm import SVC
    from sklearn.datasets import load_iris
    data = load_iris()
    X = data.data
    y = data.target
    model = SVC(kernel='linear')
    model.fit(X, y)
    predictions = model.predict(X)
    ```
    '''
    return svm

# Neural Networks
def neural_networks():
    neural = '''
    ### 🧠 Neural Networks
    Neural networks are modeled after the human brain, with layers of interconnected nodes (neurons) used for tasks like image and speech recognition.

    **📚 Example**:
    - **1️⃣2️⃣3️⃣ Classifying Handwritten Digits**: A simple neural network can be used to classify digits from the MNIST dataset.
    ```python
    from sklearn.neural_network import MLPClassifier
    from sklearn.datasets import load_iris
    data = load_iris()
    X = data.data
    y = data.target
    model = MLPClassifier(hidden_layer_sizes=(10,), max_iter=1000)
    model.fit(X, y)
    predictions = model.predict(X)
    ```
    '''
    return neural

# Sidebar for content navigation with emojis
st.sidebar.header("📚 Contents")

# Show Introduction first in the sidebar
page = st.sidebar.radio("📖 Select a Topic", 
                        ["Introduction", "Types of Machine Learning", "Popular Algorithms"])

# Conditional options based on sidebar selection
if page == "Types of Machine Learning":
    types_of_ml = st.sidebar.radio("📊 Types of Machine Learning", 
                                   ["🔸 Supervised Learning", "🔸 Unsupervised Learning", "🔸 Reinforcement Learning"])
else:
    types_of_ml = None

if page == "Popular Algorithms":
    popular_algorithms = st.sidebar.radio("🚀 Popular Algorithms", 
                                          ["🔗 Linear Regression", "📈 Logistic Regression", "🌳 Decision Trees", 
                                           "🔍 K-Nearest Neighbors (KNN)", "⚡ Support Vector Machines (SVM)", "🧠 Neural Networks"])
else:
    popular_algorithms = None

# Main content area
st.markdown("<h1 style='text-align: center; color: orange;'>Machine Learning (ML)</h1>", unsafe_allow_html=True)

# Display content based on the selected page
if page == "Introduction":
    st.markdown(introduction_to_ml())

elif types_of_ml == "🔸 Supervised Learning":
    st.markdown(supervised_learning())
elif types_of_ml == "🔸 Unsupervised Learning":
    st.markdown(unsupervised_learning())
elif types_of_ml == "🔸 Reinforcement Learning":
    st.markdown(reinforcement_learning())

elif popular_algorithms == "🔗 Linear Regression":
    st.markdown(linear_regression())
elif popular_algorithms == "📈 Logistic Regression":
    st.markdown(logistic_regression())
elif popular_algorithms == "🌳 Decision Trees":
    st.markdown(decision_trees())
elif popular_algorithms == "🔍 K-Nearest Neighbors (KNN)":
    st.markdown(knn())
elif popular_algorithms == "⚡ Support Vector Machines (SVM)":
    st.markdown(svm())
elif popular_algorithms == "🧠 Neural Networks":
    st.markdown(neural_networks())