import re
import pandas as pd
import glob
import os
from tqdm import tqdm
from datasets import load_dataset

# Download the dataset first
print("Downloading the RedStone-Code-python dataset...")
dataset = load_dataset("zjsd/RedStone-Code-python")
print("Dataset downloaded successfully!")

def detect_python_functions(text):
    if not isinstance(text, str):
        return []
        
    function_pattern = r'def\s+\w+\s*\([^)]*\)\s*:'
    lines = text.split('\n')
    function_blocks = []
    current_block = []
    in_function = False
    
    for line in lines:
        if re.search(function_pattern, line):
            if current_block and in_function:
                function_blocks.append('\n'.join(current_block))
                current_block = []
            in_function = True
            current_block = [line]
            continue
            
        if in_function:
            if line.startswith('    ') or '\t' in line or not line.strip():
                current_block.append(line)
            elif line.strip() and not line.startswith('    '):
                if current_block:
                    function_blocks.append('\n'.join(current_block))
                current_block = []
                in_function = False
    
    if current_block and in_function:
        function_blocks.append('\n'.join(current_block))
    
    def is_valid_function(block):
        has_python_keywords = any(keyword in block for keyword in 
                                ['return', 'print', 'if', 'for', 'while', '='])
        has_proper_indentation = any(line.startswith('    ') for line in block.split('\n')[1:])
        return has_python_keywords and has_proper_indentation
    
    return [block for block in function_blocks if is_valid_function(block)]

def has_python_functions(row):
    functions = detect_python_functions(row['text'])
    return len(functions) > 0

def process_in_batches(parquet_file, batch_size=10000):
    filtered_dfs = []
    total_rows = pd.read_parquet(parquet_file, columns=[]).shape[0]
    
    print(f"\nStarting to process file with {total_rows} rows")  # Debug line
    
    pbar_desc = f"Processing {os.path.basename(parquet_file)}"
    with tqdm(total=total_rows, desc=pbar_desc, position=1, leave=False) as pbar:
        for batch_start in range(0, total_rows, batch_size):
            # Read batch
            batch_df = pd.read_parquet(
                parquet_file,
                offset=batch_start,
                rows=min(batch_size, total_rows - batch_start)
            )
            
            # Debug lines
            print(f"\nProcessing batch of size: {len(batch_df)}")
            if len(batch_df) > 0:
                print(f"Sample text from batch:\n{batch_df['text'].iloc[0][:200]}...")
            
            # Filter and process batch
            filtered_batch = batch_df[batch_df.apply(has_python_functions, axis=1)].copy()
            print(f"Found {len(filtered_batch)} rows with functions in this batch")  # Debug line
            
            if len(filtered_batch) > 0:
                filtered_batch['python_functions'] = filtered_batch['text'].apply(detect_python_functions)
                filtered_dfs.append(filtered_batch)
            
            pbar.update(len(batch_df))
            pbar.set_postfix({'Found': sum(len(df) for df in filtered_dfs)})
    
    return pd.concat(filtered_dfs) if filtered_dfs else pd.DataFrame()

# Create output directory
output_dir = "filtered_python_functions"
os.makedirs(output_dir, exist_ok=True)

# Convert dataset to parquet files if needed
print("Converting dataset to parquet files...")
for split in dataset.keys():
    dataset[split].to_parquet(f"{output_dir}/redstone_{split}.parquet")

# Get list of parquet files
parq_list = glob.glob(f"{output_dir}/redstone_*.parquet")

if not parq_list:
    print("No parquet files found! Something went wrong with the dataset conversion.")
    exit(1)

print(f"Found {len(parq_list)} parquet files to process")

# Process all files with overall progress bar
total_functions_found = 0
with tqdm(total=len(parq_list), desc="Overall Progress", position=0) as pbar_files:
    for idx, parquet_file in enumerate(parq_list):
        try:
            # Process the file in batches
            filtered_df = process_in_batches(parquet_file, batch_size=10000)
            
            # Save if we found any matches
            if len(filtered_df) > 0:
                output_file = os.path.join(output_dir, f"python_functions_{idx}.parquet")
                filtered_df.to_parquet(output_file)
                total_functions_found += len(filtered_df)
                
                # Update progress bar with statistics
                pbar_files.set_postfix({
                    'Current File': f"{idx + 1}/{len(parq_list)}", 
                    'Total Found': total_functions_found
                })
                
        except Exception as e:
            print(f"\nError processing {parquet_file}: {str(e)}")
            continue
            
        pbar_files.update(1)

print(f"\nProcessing complete! Total Python functions found: {total_functions_found}")