import subprocess
import re
import csv
import os
from collections import defaultdict

def categorize_monabanq_transaction(description):
    description = description.lower()
    
    if 'ech pret' in description:
        return 'Loan Repayment'
    if 'f cotis pratiq+' in description:
        return 'Bank Fees'
    if 'google ireland' in description:
        return 'Google Services'
    if 'vir mr bataille kevin' in description:
        return 'Internal Transfer'
        
    return 'Other'

def process_monabanq_files(file_list, output_csv=False, output_dir='../../output/csv'):
    expense_summary = defaultdict(float)
    total_expenses = 0
    all_transactions = []

    for file_path in file_list:
        try:
            # Use pdftotext to extract text
            result = subprocess.run(['pdftotext', '-layout', file_path, '-'], capture_output=True, text=True, check=True)
            content = result.stdout
        except (subprocess.CalledProcessError, FileNotFoundError) as e:
            print(f"Error processing {file_path}: {e}")
            continue

        lines = content.split('\n')
        transaction_started = False
        for line in lines:
            if "SOLDE CREDITEUR AU" in line or "SOLDE DEBITEUR AU" in line:
                transaction_started = True
                continue
            if not transaction_started or not line.strip():
                continue
            if "IBAN :" in line:
                break

            # Regex to capture date, description, and debit/credit
            match = re.match(r'\s*(\d{2}/\d{2}/\d{4})\s+\d{2}/\d{2}/\d{4}\s+(.*?)(?=\s{2,}|$)(\s+[\d,.]+)?(\s+[\d,.]+)?', line)
            if match:
                op_date, description, debit_str, credit_str = match.groups()
                description = description.strip()
                debit = 0
                credit = 0
                
                if debit_str:
                    try:
                        debit = float(debit_str.strip().replace(',', '.'))
                    except (ValueError, AttributeError):
                        debit = 0
                
                if credit_str:
                    try:
                        credit = float(credit_str.strip().replace(',', '.'))
                    except (ValueError, AttributeError):
                        credit = 0
                
                category = categorize_monabanq_transaction(description)
                
                # Store transaction for CSV output
                all_transactions.append({
                    'Date': op_date,
                    'Description': description,
                    'Category': category,
                    'Debit': debit,
                    'Credit': credit,
                    'Source': os.path.basename(file_path)
                })
                
                if debit > 0 and category != 'Internal Transfer':
                    expense_summary[category] += debit
                    total_expenses += debit
    
    # Output CSV if requested
    if output_csv and all_transactions:
        csv_file = os.path.join(output_dir, 'monabanq_all_transactions.csv')
        os.makedirs(output_dir, exist_ok=True)
        with open(csv_file, 'w', newline='', encoding='utf-8') as csvfile:
            fieldnames = ['Date', 'Description', 'Category', 'Debit', 'Credit', 'Source']
            writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
            writer.writeheader()
            writer.writerows(all_transactions)
        print(f"\nTransaction data saved to {csv_file}")

    print("--- Monabanq Expense Summary for 2025 ---")
    print(f"Total Expenses Analyzed: €{total_expenses:,.2f}")
    print("\n--- Spending by Category ---")
    
    sorted_expenses = sorted(expense_summary.items(), key=lambda item: item[1], reverse=True)
    
    if total_expenses > 0:
        for category, total in sorted_expenses:
            percentage = (total / total_expenses) * 100
            print(f"{category:<25} €{total:9,.2f} ({percentage:5.2f}%)")
    else:
        print("No expenses found.")
    
    return all_transactions

if __name__ == "__main__":
    import argparse
    import glob
    
    parser = argparse.ArgumentParser(description='Process Monabanq statements')
    parser.add_argument('--pdf-dir', default='../data/pdf/monabanq', 
                       help='Directory containing Monabanq PDF files')
    parser.add_argument('--output-dir', default='../../output/csv', 
                       help='Directory to save CSV output files')
    parser.add_argument('--csv', action='store_true', 
                       help='Output transaction data to CSV files')
    args = parser.parse_args()
    
    # Get all PDF files in the directory
    pdf_files = glob.glob(os.path.join(args.pdf_dir, "*.pdf"))
    
    # Sort files by date if possible
    pdf_files.sort()
    
    # Process all PDF files in the directory
    process_monabanq_files(pdf_files, args.csv, args.output_dir)