import os
import tempfile
import zipfile
import threading
import uuid
from functools import wraps
from flask import Flask, request, render_template_string, redirect, url_for, session, send_from_directory
from werkzeug.utils import secure_filename
from PyPDF2 import PdfReader
from authlib.integrations.flask_client import OAuth

app = Flask(__name__)
app.config['UPLOAD_FOLDER'] = tempfile.mkdtemp()
app.config['MAX_CONTENT_LENGTH'] = 500 * 1024 * 1024  # 500MB limit
app.secret_key = os.getenv('SECRET_KEY', 'dev-secret-key-change-in-production')

# Entra ID Configuration
TENANT_ID = os.getenv('TENANT_ID', 'your-tenant-id')
CLIENT_ID = os.getenv('CLIENT_ID', 'your-client-id')
CLIENT_SECRET = os.getenv('CLIENT_SECRET', 'your-client-secret')

# Admin Configuration
ADMIN_USERNAME = os.getenv('ADMIN_USERNAME', 'trbcit')
ADMIN_PASSWORD = os.getenv('ADMIN_PASSWORD', 'atdrmbicn')

oauth = OAuth(app)
microsoft = oauth.register(
    name='microsoft',
    client_id=CLIENT_ID,
    client_secret=CLIENT_SECRET,
    server_metadata_url=f'https://login.microsoftonline.com/{TENANT_ID}/v2.0/.well-known/openid_configuration',
    client_kwargs={'scope': 'openid profile email'}
)

ALLOWED_EXTENSIONS = {'pdf', 'zip'}

# Global jobs storage (in production, use database)
job_queue = {}

def login_required(f):
    @wraps(f)
    def decorated_function(*args, **kwargs):
        if 'user' not in session and 'admin' not in session:
            return redirect(url_for('login'))
        return f(*args, **kwargs)
    return decorated_function

def allowed_file(filename):
    return '.' in filename and filename.rsplit('.', 1)[1].lower() in ALLOWED_EXTENSIONS

def extract_names_from_pdf(pdf_path):
    try:
        reader = PdfReader(pdf_path)
        fields = reader.get_fields()
        
        # Extract all required fields
        last_name = fields.get('Last Name', {}).get('/V', '').strip()
        first_name = fields.get('First Name', {}).get('/V', '').strip()
        grade = fields.get('Student Grade', {}).get('/V', '').strip()
        school = fields.get('Student School', {}).get('/V', '').strip()
        
        # Check for missing fields
        missing_fields = []
        if not last_name:
            missing_fields.append('Last Name')
        if not first_name:
            missing_fields.append('First Name')
        if not grade:
            missing_fields.append('Student Grade')
        if not school:
            missing_fields.append('Student School')
        
        if missing_fields:
            return {'error': f'Missing or empty fields: {", ".join(missing_fields)}'}
        
        return {
            'filename': f"{last_name}_{first_name}.pdf",
            'last_name': last_name,
            'first_name': first_name,
            'grade': grade,
            'school': school
        }
    except Exception as e:
        return {'error': f'PDF read error: {str(e)}'}

def process_job(job_id, files):
    job_queue[job_id]['status'] = 'processing'
    job_queue[job_id]['progress'] = 'Starting job processing...'
    processed_files = []
    temp_extract_dirs = []
    
    # Create base Episode directory for this job
    episode_dir = os.path.join(app.config['UPLOAD_FOLDER'], f'Episode_{job_id}')
    os.makedirs(episode_dir, exist_ok=True)
    job_queue[job_id]['progress'] = 'Created output directory structure'
    
    # Analyze ZIP contents before processing
    zip_contents = {}
    for file_info in files:
        if file_info['name'].lower().endswith('.zip'):
            try:
                with zipfile.ZipFile(file_info['path'], 'r') as zip_ref:
                    pdf_files = [f for f in zip_ref.namelist() if f.lower().endswith('.pdf')]
                    zip_contents[file_info['name']] = pdf_files
            except Exception as e:
                zip_contents[file_info['name']] = [f"Error reading ZIP: {str(e)}"]
    
    job_queue[job_id]['zip_contents'] = zip_contents
    
    total_files = sum(1 for file_info in files if file_info['name'].lower().endswith('.pdf')) + \
                  sum(len(zip_contents.get(file_info['name'], [])) 
                      for file_info in files if file_info['name'].lower().endswith('.zip'))
    
    processed_count = 0
    
    processed_count = 0
    
    for file_info in files:
        filepath = file_info['path']
        filename = file_info['name']
        
        if filename.lower().endswith('.zip'):
            job_queue[job_id]['progress'] = f'Extracting ZIP archive: {filename}'
            # Extract ZIP
            extract_dir = os.path.join(app.config['UPLOAD_FOLDER'], f'extract_{job_id}_{os.path.splitext(filename)[0]}')
            os.makedirs(extract_dir, exist_ok=True)
            temp_extract_dirs.append(extract_dir)
            with zipfile.ZipFile(filepath, 'r') as zip_ref:
                zip_ref.extractall(extract_dir)
            job_queue[job_id]['progress'] = f'Extracted {len(zip_ref.namelist())} files from {filename}'
            
            # Process PDFs in extract_dir
            for root, dirs, files_in_zip in os.walk(extract_dir):
                for f in files_in_zip:
                    if f.lower().endswith('.pdf'):
                        pdf_path = os.path.join(root, f)
                        job_queue[job_id]['progress'] = f'Processing PDF: {f}'
                        pdf_info = extract_names_from_pdf(pdf_path)
                        if 'error' in pdf_info:
                            processed_files.append(('skipped', f, pdf_info['error']))
                            job_queue[job_id]['progress'] = f'Skipped {f} - {pdf_info["error"]}'
                        else:
                            job_queue[job_id]['progress'] = f'Extracted data for {pdf_info["first_name"]} {pdf_info["last_name"]}'
                            # Create folder structure: Episode/School/Grade/
                            school_dir = os.path.join(episode_dir, pdf_info['school'])
                            grade_dir = os.path.join(school_dir, pdf_info['grade'])
                            os.makedirs(grade_dir, exist_ok=True)
                            
                            # Move file to appropriate folder with new name
                            new_path = os.path.join(grade_dir, pdf_info['filename'])
                            counter = 1
                            while os.path.exists(new_path):
                                base, ext = os.path.splitext(pdf_info['filename'])
                                new_path = os.path.join(grade_dir, f"{base}_{counter}{ext}")
                                counter += 1
                            os.rename(pdf_path, new_path)
                            processed_files.append(('success', os.path.relpath(new_path, episode_dir), new_path))
                            processed_count += 1
                            job_queue[job_id]['progress'] = f'Organized {processed_count}/{total_files} files'
        else:
            # Single PDF
            job_queue[job_id]['progress'] = f'Processing PDF: {filename}'
            pdf_info = extract_names_from_pdf(filepath)
            if 'error' in pdf_info:
                processed_files.append(('skipped', filename, pdf_info['error']))
                job_queue[job_id]['progress'] = f'Skipped {filename} - {pdf_info["error"]}'
            else:
                job_queue[job_id]['progress'] = f'Extracted data for {pdf_info["first_name"]} {pdf_info["last_name"]}'
                # Create folder structure: Episode/School/Grade/
                school_dir = os.path.join(episode_dir, pdf_info['school'])
                grade_dir = os.path.join(school_dir, pdf_info['grade'])
                os.makedirs(grade_dir, exist_ok=True)
                
                # Move file to appropriate folder with new name
                new_filepath = os.path.join(grade_dir, pdf_info['filename'])
                counter = 1
                while os.path.exists(new_filepath):
                    base, ext = os.path.splitext(pdf_info['filename'])
                    new_filepath = os.path.join(grade_dir, f"{base}_{counter}{ext}")
                    counter += 1
                os.rename(filepath, new_filepath)
                processed_files.append(('success', os.path.relpath(new_filepath, episode_dir), new_filepath))
                processed_count += 1
                job_queue[job_id]['progress'] = f'Organized {processed_count}/{total_files} files'
    
    job_queue[job_id]['progress'] = 'Creating ZIP archive...'
    # Create ZIP of the entire Episode directory structure
    successful_files = [p for p in processed_files if p[0] == 'success']
    if successful_files:
        try:
            zip_output = os.path.join(app.config['UPLOAD_FOLDER'], f'renamed_{job_id}.zip')
            with zipfile.ZipFile(zip_output, 'w', zipfile.ZIP_DEFLATED) as zip_out:
                for root, dirs, files_in_dir in os.walk(episode_dir):
                    for file in files_in_dir:
                        file_path = os.path.join(root, file)
                        arcname = os.path.relpath(file_path, episode_dir)
                        zip_out.write(file_path, arcname)
            job_queue[job_id]['zip_path'] = zip_output
            job_queue[job_id]['zip_name'] = f'renamed_{job_id}.zip'
            job_queue[job_id]['progress'] = f'Created ZIP archive with {len(successful_files)} organized files'
        except Exception as e:
            job_queue[job_id]['progress'] = f'Error creating ZIP: {str(e)}'
            job_queue[job_id]['status'] = 'error'
    else:
        job_queue[job_id]['progress'] = 'No files to archive - all files were skipped'
    
    job_queue[job_id]['status'] = 'completed'
    job_queue[job_id]['processed_files'] = processed_files
    job_queue[job_id]['skipped'] = [(p[1], p[2]) for p in processed_files if p[0] == 'skipped']

@app.route('/login')
def login():
    return render_template_string('''
    <!DOCTYPE html>
    <html>
    <head>
        <title>Login</title>
        <style>
            body { font-family: Arial, sans-serif; background-color: #f4f4f4; margin: 0; padding: 20px; text-align: center; }
            .login-container { background-color: #fff; padding: 30px; border-radius: 10px; box-shadow: 0 0 10px rgba(0,0,0,0.1); display: inline-block; margin: 20px; }
            h1 { color: #333; }
            .login-options { display: flex; justify-content: space-around; flex-wrap: wrap; }
            .login-option { margin: 10px; }
            a { color: #007bff; text-decoration: none; padding: 15px 30px; background-color: #007bff; color: white; border-radius: 5px; display: inline-block; }
            a:hover { background-color: #0056b3; }
            form { margin-top: 20px; }
            input[type="text"], input[type="password"] { padding: 10px; margin: 5px; width: 200px; border: 1px solid #ccc; border-radius: 5px; }
            input[type="submit"] { background-color: #28a745; color: white; border: none; padding: 10px 20px; border-radius: 5px; cursor: pointer; }
            input[type="submit"]:hover { background-color: #218838; }
        </style>
    </head>
    <body>
        <img src="/static/trbc-logo-full.png" alt="Logo" width="200">
        <h1>PDF Renamer Login</h1>
        <div class="login-options">
            <div class="login-option">
                <h2>Microsoft Entra ID</h2>
                <a href="/entra-login">Login with Microsoft</a>
            </div>
            <div class="login-option">
                <h2>Admin Login</h2>
                <form method="post" action="/admin-login">
                    <input type="text" name="username" placeholder="Username" required><br>
                    <input type="password" name="password" placeholder="Password" required><br>
                    <input type="submit" value="Admin Login">
                </form>
            </div>
        </div>
    </body>
    </html>
    ''')

@app.route('/entra-login')
def entra_login():
    redirect_uri = url_for('auth', _external=True)
    return microsoft.authorize_redirect(redirect_uri)

@app.route('/admin-login', methods=['POST'])
def admin_login():
    username = request.form.get('username')
    password = request.form.get('password')
    if username == ADMIN_USERNAME and password == ADMIN_PASSWORD:
        session['admin'] = True
        return redirect(url_for('upload_files'))
    else:
        return render_template_string('''
        <!DOCTYPE html>
        <html>
        <head>
            <title>Login Failed</title>
            <style>
                body { font-family: Arial, sans-serif; background-color: #f4f4f4; text-align: center; padding: 50px; }
                .error { color: #dc3545; background-color: #f8d7da; padding: 20px; border-radius: 5px; border: 1px solid #f5c6cb; }
                a { color: #007bff; text-decoration: none; }
            </style>
        </head>
        <body>
            <div class="error">
                <h1>Login Failed</h1>
                <p>Invalid username or password.</p>
                <a href="/login">Try Again</a>
            </div>
        </body>
        </html>
        ''')

@app.route('/auth')
def auth():
    token = microsoft.authorize_access_token()
    user = microsoft.parse_id_token(token)
    session['user'] = user
    return redirect(url_for('upload_files'))

@app.route('/logout')
@login_required
def logout():
    session.pop('user', None)
    session.pop('admin', None)
    return redirect(url_for('login'))

@app.route('/', methods=['GET', 'POST'])
@login_required
def upload_files():
    if request.method == 'POST':
        files = request.files.getlist('files')
        if not files or all(not f.filename for f in files):
            return redirect(url_for('upload_files'))
        
        job_id = str(uuid.uuid4())
        job_queue[job_id] = {
            'status': 'queued',
            'files': [],
            'zip_path': None,
            'zip_name': None,
            'processed_files': [],
            'skipped': []
        }
        
        file_list = []
        for file in files:
            if file and allowed_file(file.filename):
                filename = secure_filename(file.filename)
                filepath = os.path.join(app.config['UPLOAD_FOLDER'], f"{job_id}_{filename}")
                file.save(filepath)
                file_list.append({'name': filename, 'path': filepath})
        
        job_queue[job_id]['files'] = file_list
        
        # Start processing in background
        thread = threading.Thread(target=process_job, args=(job_id, file_list))
        thread.daemon = True
        thread.start()
        
        return redirect(url_for('jobs'))
    
    return render_template_string('''
    <!DOCTYPE html>
    <html>
    <head>
        <title>PDF Renamer</title>
        <style>
            body { font-family: Arial, sans-serif; background-color: #f4f4f4; margin: 0; padding: 20px; text-align: center; }
            img { margin-bottom: 20px; }
            h1 { color: #333; }
            form { background-color: #fff; padding: 20px; border-radius: 10px; box-shadow: 0 0 10px rgba(0,0,0,0.1); display: inline-block; }
            input[type="file"] { margin: 10px 0; }
            input[type="submit"] { background-color: #28a745; color: white; border: none; padding: 10px 20px; border-radius: 5px; cursor: pointer; }
            input[type="submit"]:hover { background-color: #218838; }
            .logout { position: absolute; top: 20px; right: 20px; background-color: #dc3545; color: white; text-decoration: none; padding: 10px 20px; border-radius: 5px; }
            .logout:hover { background-color: #c82333; }
            .view-jobs-btn { background-color: #007bff; color: white; text-decoration: none; padding: 10px 20px; border-radius: 5px; display: inline-block; margin: 10px 0; }
            .view-jobs-btn:hover { background-color: #0056b3; }
        </style>
    </head>
    <body>
        <a href="/logout" class="logout">Logout</a>
        <img src="/static/trbc-logo-full.png" alt="Logo" width="200">
        <h1>Upload PDF Files or ZIP to Rename</h1>
        <a href="/jobs" class="view-jobs-btn">View Jobs</a>
        <br><br>
        <form method="post" enctype="multipart/form-data">
            <input type="file" name="files" multiple accept=".pdf,.zip">
            <br><br>
            <input type="submit" value="Process PDFs">
        </form>
    </body>
    </html>
    ''')

@app.route('/jobs')
@login_required
def jobs():
    return render_template_string('''
    <!DOCTYPE html>
    <html>
    <head>
        <title>Jobs</title>
        <style>
            body { font-family: Arial, sans-serif; background-color: #f4f4f4; margin: 0; padding: 20px; text-align: center; }
            img { margin-bottom: 20px; }
            h1 { color: #333; }
            .job { background-color: #fff; margin: 10px auto; padding: 15px; border-radius: 10px; box-shadow: 0 0 10px rgba(0,0,0,0.1); max-width: 800px; text-align: left; }
            .status { padding: 5px 10px; border-radius: 5px; color: white; font-weight: bold; }
            .status.queued { background-color: #ffc107; }
            .status.processing { background-color: #17a2b8; }
            .status.completed { background-color: #28a745; }
            .status.error { background-color: #dc3545; }
            .progress-text { color: #17a2b8; font-style: italic; }
            .download-btn { background-color: #007bff; color: white; text-decoration: none; padding: 8px 16px; border-radius: 5px; margin-left: 10px; }
            .download-btn:hover { background-color: #0056b3; }
            .logout { position: absolute; top: 20px; right: 20px; background-color: #dc3545; color: white; text-decoration: none; padding: 10px 20px; border-radius: 5px; }
            .logout:hover { background-color: #c82333; }
            .zip-content { background-color: #f8f9fa; padding: 10px; margin: 5px 0; border-radius: 5px; border-left: 4px solid #007bff; }
            ul { list-style-type: none; padding: 0; }
            li { background-color: #ffffff; margin: 2px 0; padding: 5px; border-radius: 3px; }
        </style>
    </head>
    <body>
        <a href="/logout" class="logout">Logout</a>
        <img src="/static/trbc-logo-full.png" alt="Logo" width="200">
        <h1>Processing Jobs</h1>
        {% for job_id, job in jobs.items() %}
        <div class="job">
            <h3>Job {{ job_id[:8] }}</h3>
            <p><strong>Status:</strong> <span class="status {{ job.status }}">{{ job.status.title() }}</span></p>
            {% if job.status == 'processing' and job.progress %}
            <p><strong>Progress:</strong> <span class="progress-text">{{ job.progress }}</span></p>
            {% endif %}
            <p><strong>Files:</strong> {{ job.files|length }}</p>
            {% if job.zip_contents %}
            <p><strong>ZIP Contents:</strong></p>
            {% for zip_name, pdf_files in job.zip_contents.items() %}
            <div class="zip-content">
                <strong>{{ zip_name }}:</strong>
                <ul>
                {% for pdf_file in pdf_files %}
                    <li>{{ pdf_file }}</li>
                {% endfor %}
                </ul>
            </div>
            {% endfor %}
            {% endif %}
            {% if job.status == 'completed' %}
                {% if job.zip_name %}
                <p><a href="/download/{{ job.zip_name }}" class="download-btn">Download ZIP</a></p>
                {% else %}
                <p><em>No files were successfully processed to create a ZIP archive.</em></p>
                {% endif %}
                {% if job.skipped %}
                <p><strong>Skipped Files:</strong></p>
                <ul>
                {% for skip_info in job.skipped %}
                    <li><strong>{{ skip_info[0] }}</strong>: {{ skip_info[1] }}</li>
                {% endfor %}
                </ul>
                {% endif %}
            {% endif %}
        </div>
        {% endfor %}
        {% if not jobs %}
        <p>No jobs yet. <a href="/">Upload some files</a> to get started.</p>
        {% endif %}
    </body>
    </html>
    ''', jobs=job_queue)

@app.route('/download/<filename>')
@login_required
def download(filename):
    # Security check: only allow downloading files that belong to completed jobs
    for job_id, job in job_queue.items():
        if job.get('status') == 'completed' and job.get('zip_name') == filename:
            file_path = os.path.join(app.config['UPLOAD_FOLDER'], filename)
            if os.path.exists(file_path):
                return send_from_directory(app.config['UPLOAD_FOLDER'], filename, as_attachment=True)
    return "File not found or access denied", 404

if __name__ == '__main__':
    app.run(debug=True, port=3000)