import os
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
from sklearn.decomposition import PCA
from sklearn.feature_extraction.text import TfidfVectorizer
import tempfile

def load_data(file_path):
    """
    Load data from an Excel or CSV file
    
    Args:
        file_path (str): Path to the file
        
    Returns:
        pd.DataFrame: Loaded data
    """
    file_ext = os.path.splitext(file_path)[1].lower()
    
    if file_ext == '.xlsx' or file_ext == '.xls':
        return pd.read_excel(file_path)
    elif file_ext == '.csv':
        return pd.read_csv(file_path)
    else:
        raise ValueError(f"Unsupported file format: {file_ext}. Please upload an Excel or CSV file.")

def export_data(df, file_name, format_type="excel"):
    """
    Export dataframe to file
    
    Args:
        df (pd.DataFrame): Dataframe to export
        file_name (str): Name of the output file
        format_type (str): "excel" or "csv"
        
    Returns:
        str: Path to the exported file
    """
    # Create export directory if it doesn't exist
    export_dir = "exports"
    os.makedirs(export_dir, exist_ok=True)
    
    # Full path for the export file
    export_path = os.path.join(export_dir, file_name)
    
    # Export based on format type
    if format_type == "excel":
        df.to_excel(export_path, index=False)
    else:
        df.to_csv(export_path, index=False)
    
    return export_path

def visualize_results(df, text_column, category_column="Category"):
    """
    Create visualization of classification results
    
    Args:
        df (pd.DataFrame): Dataframe with classification results
        text_column (str): Name of the column containing text data
        category_column (str): Name of the column containing categories
        
    Returns:
        matplotlib.figure.Figure: Visualization figure
    """
    # Check if category column exists
    if category_column not in df.columns:
        # Create a simple figure with a message
        fig, ax = plt.subplots(figsize=(10, 6))
        ax.text(0.5, 0.5, "No categories to display", 
                ha='center', va='center', fontsize=12)
        ax.set_title('No Classification Results Available')
        plt.tight_layout()
        return fig
    
    # Get categories and their counts
    category_counts = df[category_column].value_counts()
    
    # Create a new figure
    fig, ax = plt.subplots(figsize=(10, 6))
    
    # Create the histogram
    bars = ax.bar(category_counts.index, category_counts.values)
    
    # Add value labels on top of each bar
    for bar in bars:
        height = bar.get_height()
        ax.text(bar.get_x() + bar.get_width()/2., height,
                f'{int(height)}',
                ha='center', va='bottom')
    
    # Customize the plot
    ax.set_xlabel('Categories')
    ax.set_ylabel('Number of Texts')
    ax.set_title('Distribution of Classified Texts')
    
    # Rotate x-axis labels if they're too long
    plt.xticks(rotation=45, ha='right')
    
    # Add grid
    ax.grid(True, linestyle='--', alpha=0.7)
    
    plt.tight_layout()
    
    return fig

def validate_results(df, text_columns, client):
    """
    Use LLM to validate the classification results
    
    Args:
        df (pd.DataFrame): Dataframe with classification results
        text_columns (list): List of column names containing text data
        client: LiteLLM client
        
    Returns:
        str: Validation report
    """
    try:
        # Sample a few rows for validation
        sample_size = min(5, len(df))
        sample_df = df.sample(n=sample_size, random_state=42)
        
        # Build validation prompt
        validation_prompts = []
        for _, row in sample_df.iterrows():
            # Combine text from all selected columns
            text = " ".join(str(row[col]) for col in text_columns)
            assigned_category = row["Category"]
            confidence = row["Confidence"]
            
            validation_prompts.append(
                f"Text: {text}\nAssigned Category: {assigned_category}\nConfidence: {confidence}\n"
            )
        
        prompt = """
        As a validation expert, review the following text classifications and provide feedback.
        For each text, assess whether the assigned category seems appropriate:
        
        {}
        
        Provide a brief validation report with:
        1. Overall accuracy assessment (0-100%)
        2. Any potential misclassifications identified
        3. Suggestions for improvement
        
        Keep your response under 300 words.
        """.format("\n---\n".join(validation_prompts))
        
        # Call LLM API
        response = client.chat.completions.create(
            model="gpt-3.5-turbo",
            messages=[{"role": "user", "content": prompt}],
            temperature=0.3,
            max_tokens=400
        )
        
        validation_report = response.choices[0].message.content.strip()
        return validation_report
    
    except Exception as e:
        return f"Validation failed: {str(e)}"


def create_example_file():
    """
    Create an example CSV file for testing
    
    Returns:
        str: Path to the created file
    """
    # Create some example data
    data = {
        "text": [
            "I absolutely love this product! It exceeded all my expectations.",
            "The service was terrible and the staff was rude.",
            "The product arrived on time but was slightly damaged.",
            "I have mixed feelings about this. Some features are great, others not so much.",
            "This is a complete waste of money. Do not buy!",
            "The customer service team was very helpful in resolving my issue.",
            "It's okay, nothing special but gets the job done.",
            "I'm extremely disappointed with the quality of this product.",
            "This is the best purchase I've made all year!",
            "It's reasonably priced and works as expected."
        ]
    }
    
    # Create dataframe
    df = pd.DataFrame(data)
    
    # Save to a CSV file
    example_dir = "examples"
    os.makedirs(example_dir, exist_ok=True)
    file_path = os.path.join(example_dir, "sample_reviews.csv")
    df.to_csv(file_path, index=False)
    
    return file_path