# Filename: Generate_sudokuCSV.py (v1.2 - API FIX)
# Description: This version corrects the bug where the '.solution' attribute
#              was incorrectly accessed. It now properly uses the '.solve()'
#              method as required by the 'py-sudoku' library API.

import os
import sys
import subprocess

# --- Environment Setup and Dependency Installation ---

def setup_dependencies():
    """Checks for and installs required packages ('py-sudoku' and 'pandas')."""
    print("--- Checking Dependencies ---")
    try:
        import sudoku
        import pandas
        print("Dependencies 'py-sudoku' and 'pandas' are already satisfied.")
        return
    except ImportError:
        print("A required package is missing. Attempting installation...")
        packages_to_install = ['py-sudoku', 'pandas']
        try:
            command = [sys.executable, "-m", "pip", "install"] + packages_to_install
            print(f"Running command: {' '.join(command)}")
            subprocess.check_call(command)
            print("--- Dependencies installed successfully. ---")
        except subprocess.CalledProcessError as e:
            print("\nFATAL: Failed to install required packages automatically.")
            print("Please run this command in a new cell: !pip install py-sudoku pandas")
            sys.exit(f"Installation failed with error: {e}")

# Run the dependency check immediately
setup_dependencies()

# Now we can safely import the libraries
from sudoku import Sudoku
import pandas as pd


# --- CORE GENERATION FUNCTION (for portability) ---

def Generate_sudokucsv(num_puzzles: int = 10000, difficulty: float = 0.7, output_path: str = './sudoku.csv'):
    """
    Generates a specified number of Sudoku puzzles and their solutions,
    saving them to a CSV file.

    Args:
        num_puzzles (int): The number of puzzles to generate.
        difficulty (float): The difficulty of the puzzles (0.0 to 1.0).
        output_path (str): The file path for the output CSV.
    
    Returns:
        bool: True if the file was created or already exists, False on failure.
    """
    print("\n" + "="*50)
    print("Sudoku CSV Generator Initialized")
    print(f"Puzzles to generate: {num_puzzles}")
    print(f"Difficulty setting:  {difficulty}")
    print(f"Output file:         {output_path}")
    print("="*50)

    if os.path.exists(output_path):
        print(f"INFO: File '{output_path}' already exists. Skipping generation.")
        return True

    board_to_string = lambda board: "".join(str(cell) if cell is not None else '0' for row in board for cell in row)
    data = []
    
    print("Generating puzzles... this may take a few moments.")
    try:
        for i in range(num_puzzles):
            puzzle_obj = Sudoku(3, 3).difficulty(difficulty)
            quiz_board = puzzle_obj.board

            # --- API FIX IS HERE ---
            # 1. Call the .solve() method on the original puzzle object.
            solved_puzzle_obj = puzzle_obj.solve()
            # 2. Get the .board attribute from the NEW solved object.
            solution_board = solved_puzzle_obj.board
            
            if quiz_board is None or solution_board is None:
                # This might happen if the generator creates an invalid/unsolvable puzzle
                print(f"\nWarning: Skipping puzzle {i+1} due to generation/solving error.")
                continue

            data.append({
                'quizzes': board_to_string(quiz_board),
                'solutions': board_to_string(solution_board)
            })

            # Progress indicator
            progress = (i + 1) / num_puzzles
            bar_length = 40
            filled_len = int(bar_length * progress)
            bar = '█' * filled_len + '-' * (bar_length - filled_len)
            sys.stdout.write(f'\rProgress: |{bar}| {progress*100:5.1f}%')
            sys.stdout.flush()

        print("\n\nGeneration complete. Creating DataFrame and saving to CSV...")

        if not data:
            print("ERROR: No data was generated. Cannot create CSV file.")
            return False

        df = pd.DataFrame(data)
        df.to_csv(output_path, index=False)

        if os.path.exists(output_path):
            print(f"SUCCESS: '{output_path}' created with {len(df)} puzzles.")
            return True
        else:
            print(f"FAILURE: An error occurred and '{output_path}' was not created.")
            return False

    except Exception as e:
        print(f"\nAn unexpected error occurred during generation: {e}")
        import traceback
        traceback.print_exc()
        return False


# --- MAIN EXECUTION BLOCK ---

if __name__ == '__main__':
    try:
        from google.colab import files
        output_file_path = 'sudoku.csv'
        print(f"Running in Google Colab. Output will be saved to '{output_file_path}'.")
    except ImportError:
        output_file_path = './sudoku.csv'
        print(f"Running in local environment. Output will be saved to '{output_file_path}'.")

    # Execute the generation process
    Generate_sudokucsv(num_puzzles=20000, difficulty=0.7, output_path=output_file_path)