import os
from dotenv import load_dotenv
import json

# Load environment variables FIRST
load_dotenv()

from flask import Flask, render_template, redirect, url_for, flash, session, request, jsonify, send_file
from flask_login import LoginManager, login_user, logout_user, login_required, current_user
from werkzeug.security import generate_password_hash, check_password_hash
import requests
import uuid
from urllib.parse import urlencode
import re
from datetime import datetime
from sqlalchemy.orm import joinedload

# Import models and database
from models import db, User, Introduction, ProfileSummary, WorkExperience, Project, Education, Skill, Achievement, ProfileSectionOrder

app = Flask(__name__)

# Configure Flask
app.config['SECRET_KEY'] = os.environ.get('SECRET_KEY', 'dev-secret-key-change-in-production')
app.config['SQLALCHEMY_DATABASE_URI'] = os.environ.get('DATABASE_URL') or os.environ.get('SQLALCHEMY_DATABASE_URI')
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False

# Initialize extensions
db.init_app(app)
# Note: CSRFProtect disabled for now, using simple token validation

# Configure Flask-Login
login_manager = LoginManager()
login_manager.init_app(app)
login_manager.login_view = 'signin'
login_manager.login_message = 'Please sign in to access this page.'
login_manager.login_message_category = 'info'

@login_manager.user_loader
def load_user(user_id):
    return db.session.get(User, str(user_id))

# Admin required decorator
def admin_required(f):
    """Decorator to require admin access"""
    @login_required
    def decorated_function(*args, **kwargs):
        if not current_user.is_admin:
            flash('You do not have permission to access this page.', 'error')
            return redirect(url_for('profile'))
        return f(*args, **kwargs)
    decorated_function.__name__ = f.__name__
    return decorated_function

# Note: CSRF protection disabled for simplicity in this development version

# GitHub OAuth Configuration
GITHUB_CLIENT_ID = os.environ.get('GITHUB_CLIENT_ID')
GITHUB_CLIENT_SECRET = os.environ.get('GITHUB_CLIENT_SECRET')
# Auto-detect the correct callback URL based on environment
SPACE_HOST = os.environ.get('SPACE_HOST')
if SPACE_HOST:
    GITHUB_REDIRECT_URI = f'https://{SPACE_HOST}/api/auth/github/callback'
else:
    GITHUB_REDIRECT_URI = os.environ.get('GITHUB_OAUTH_BACKEND_REDIRECT', 'http://127.0.0.1:5000/auth/github/callback')

# GitHub OAuth Functions
def generate_github_auth_url():
    """Generate GitHub OAuth authorization URL"""
    params = {
        'client_id': GITHUB_CLIENT_ID,
        'redirect_uri': GITHUB_REDIRECT_URI,
        'scope': 'user:email',
        'state': str(uuid.uuid4())  # Simple CSRF protection
    }
    return f"https://github.com/login/oauth/authorize?{urlencode(params)}"

def exchange_code_for_token(code):
    """Exchange authorization code for access token"""
    data = {
        'client_id': GITHUB_CLIENT_ID,
        'client_secret': GITHUB_CLIENT_SECRET,
        'code': code,
        'redirect_uri': GITHUB_REDIRECT_URI,
    }
    
    headers = {
        'Accept': 'application/json'
    }
    
    response = requests.post('https://github.com/login/oauth/access_token', 
                           data=data, headers=headers)
    
    if response.status_code == 200:
        result = response.json()
        return result.get('access_token')
    return None

def get_github_user_info(access_token):
    """Get user information from GitHub API"""
    headers = {
        'Authorization': f'token {access_token}',
        'Accept': 'application/json'
    }
    
    response = requests.get('https://api.github.com/user', headers=headers)
    
    if response.status_code == 200:
        return response.json()
    return None

def get_github_user_email(access_token):
    """Get user's primary email from GitHub API"""
    headers = {
        'Authorization': f'token {access_token}',
        'Accept': 'application/json'
    }
    
    response = requests.get('https://api.github.com/user/emails', headers=headers)
    
    if response.status_code == 200:
        emails = response.json()
        # Find primary email
        for email in emails:
            if email.get('primary') and email.get('verified'):
                return email.get('email')
        # If no primary verified email, use the first one
        if emails:
            return emails[0].get('email')
    return None

# Email validation function
def validate_email_format(email):
    """Validate email format with flexible rules"""
    import re
    basic_pattern = r'^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$'
    if re.match(basic_pattern, email):
        return None
    return "Invalid email format"

# Routes
@app.route('/')
def index():
    if current_user.is_authenticated:
        return redirect(url_for('profile'))
    return redirect(url_for('signin'))

@app.route('/signin', methods=['GET', 'POST'])
def signin():
    if current_user.is_authenticated:
        return redirect(url_for('profile'))
    
    if request.method == 'POST':
        email = request.form.get('email', '').strip()
        password = request.form.get('password', '')
        
        if not email or not password:
            flash('Please enter both email and password.', 'error')
            return render_template('signin.html')
        
        user = User.query.filter_by(email=email).first()
        
        if user and user.check_password(password):
            # Check if user should be admin
            admin_email = os.environ.get('ADMIN_EMAIL')
            if admin_email and email.lower() == admin_email.lower():
                if not user.is_admin:
                    user.is_admin = True
                    user.role = 'Admin'
                    db.session.commit()
                    flash('Admin access granted!', 'success')
            
            login_user(user)
            next_page = request.args.get('next')
            return redirect(next_page or url_for('profile'))
        else:
            flash('Invalid email or password.', 'error')
    
    return render_template('signin.html')

@app.route('/signup', methods=['GET', 'POST'])
def signup():
    if current_user.is_authenticated:
        return redirect(url_for('profile'))
    
    if request.method == 'POST':
        name = request.form.get('name', '').strip()
        email = request.form.get('email', '').strip()
        password = request.form.get('password', '')
        password_confirm = request.form.get('password_confirm', '')
        
        # Validation
        errors = []
        
        if not name:
            errors.append('Name is required')
        
        if not email:
            errors.append('Email is required')
        else:
            email_error = validate_email_format(email)
            if email_error:
                errors.append(email_error)
        
        if not password:
            errors.append('Password is required')
        elif len(password) < 8:
            errors.append('Password must be at least 8 characters long')
        
        if not password_confirm:
            errors.append('Please confirm your password')
        elif password != password_confirm:
            errors.append('Passwords do not match')
        
        # Check if email already exists
        if email and User.query.filter_by(email=email).first():
            errors.append('Email already registered')
        
        if errors:
            for error in errors:
                flash(error, 'error')
            return render_template('signup.html')
        
        # Create new user
        new_user = User(
            id=uuid.uuid4(),
            name=name,
            email=email
        )
        new_user.set_password(password)
        
        # Check if user should be admin
        admin_email = os.environ.get('ADMIN_EMAIL')
        if admin_email and email.lower() == admin_email.lower():
            new_user.is_admin = True
            new_user.role = 'Admin'
        
        try:
            db.session.add(new_user)
            db.session.commit()
            
            if new_user.is_admin:
                flash('Admin account created successfully! Please sign in.', 'success')
            else:
                flash('Account created successfully! Please sign in.', 'success')
            return redirect(url_for('signin'))
        except Exception as e:
            db.session.rollback()
            flash('An error occurred while creating your account. Please try again.', 'error')
    
    return render_template('signup.html')

@app.route('/logout')
@login_required
def logout():
    logout_user()
    flash('You have been logged out successfully.', 'success')
    return redirect(url_for('signin'))

@app.route('/profile')
@login_required
def profile():
    # Check if user has a profile
    intro = Introduction.query.filter_by(user_id=current_user.id).first()
    has_profile = intro is not None
    
    if has_profile:
        # Get all profile data
        summary = ProfileSummary.query.filter_by(user_id=current_user.id).first()
        work_experiences = WorkExperience.query.filter_by(user_id=current_user.id).order_by(WorkExperience.order).all()
        projects = Project.query.filter_by(user_id=current_user.id).order_by(Project.order).all()
        educations = Education.query.filter_by(user_id=current_user.id).order_by(Education.order).all()
        skills = Skill.query.filter_by(user_id=current_user.id).order_by(Skill.order).all()
        achievements = Achievement.query.filter_by(user_id=current_user.id).order_by(Achievement.order).all()
        
        # Get section order if exists
        section_order_obj = ProfileSectionOrder.query.filter_by(user_id=current_user.id).first()
        section_order = section_order_obj.section_order if section_order_obj else [
            'introduction', 'profile_summary', 'work_experience', 
            'projects', 'education', 'skills', 'achievements'
        ]
        
        return render_template('profile.html',
                             has_profile=True,
                             intro=intro,
                             summary=summary,
                             work_experiences=work_experiences,
                             projects=projects,
                             educations=educations,
                             skills=skills,
                             achievements=achievements,
                             section_order=section_order)
    else:
        return render_template('profile.html', has_profile=False)

@app.route('/forgot-password')
def forgot_password():
    return render_template('forgot_password.html')

# GitHub OAuth Routes
@app.route('/auth/github')
def github_auth():
    """Initiate GitHub OAuth flow"""
    if not GITHUB_CLIENT_ID or not GITHUB_CLIENT_SECRET:
        flash('GitHub OAuth is not configured. Please check your environment variables.', 'error')
        return redirect(url_for('signin'))
    
    auth_url = generate_github_auth_url()
    return redirect(auth_url)

@app.route('/api/auth/github/callback')
def github_callback():
    """Handle GitHub OAuth callback"""
    # Check for errors
    error = request.args.get('error')
    if error:
        flash(f'GitHub authentication failed: {error}', 'error')
        return redirect(url_for('signin'))
    
    # Get authorization code and state
    code = request.args.get('code')
    state = request.args.get('state')
    
    if not code:
        flash('Authorization code not received from GitHub.', 'error')
        return redirect(url_for('signin'))
    
    # Exchange code for access token
    access_token = exchange_code_for_token(code)
    if not access_token:
        flash('Failed to exchange authorization code for access token.', 'error')
        return redirect(url_for('signin'))
    
    # Get user information from GitHub
    github_user = get_github_user_info(access_token)
    if not github_user:
        flash('Failed to retrieve user information from GitHub.', 'error')
        return redirect(url_for('signin'))
    
    # Get user email
    email = get_github_user_email(access_token)
    if not email:
        flash('Could not retrieve email from GitHub. Please ensure your email is public and verified.', 'error')
        return redirect(url_for('signin'))
    
    # Check if user exists
    user = User.query.filter_by(email=email).first()
    
    if user:
        # Existing user - check if they should be admin
        admin_email = os.environ.get('ADMIN_EMAIL')
        if admin_email and email.lower() == admin_email.lower():
            if not user.is_admin:
                user.is_admin = True
                user.role = 'Admin'
                db.session.commit()
                flash('Admin access granted!', 'success')
        
        login_user(user)
        flash(f'Welcome back, {user.name}!', 'success')
        return redirect(url_for('profile'))
    else:
        # New user - create account
        # Generate a random password for GitHub users
        import secrets
        random_password = secrets.token_urlsafe(32)
        
        new_user = User(
            id=uuid.uuid4(),
            name=github_user.get('name', github_user.get('login', 'GitHub User')),
            email=email
        )
        new_user.set_password(random_password)
        
        # Check if user should be admin
        admin_email = os.environ.get('ADMIN_EMAIL')
        if admin_email and email.lower() == admin_email.lower():
            new_user.is_admin = True
            new_user.role = 'Admin'
        
        try:
            db.session.add(new_user)
            db.session.commit()
            login_user(new_user)
            
            if new_user.is_admin:
                flash(f'Admin account created successfully! Welcome, {new_user.name}!', 'success')
            else:
                flash(f'Account created successfully! Welcome, {new_user.name}!', 'success')
            return redirect(url_for('profile'))
        except Exception as e:
            db.session.rollback()
            flash('Failed to create account. Please try again.', 'error')
            return redirect(url_for('signin'))

# Profile Creation Routes
@app.route('/profile/create', methods=['GET', 'POST'])
@login_required
def create_profile():
    """Start profile creation process"""
    # Check if user already has a profile
    if current_user.introduction:
        flash('You already have a profile. View or edit it from your profile page.', 'info')
        return redirect(url_for('profile'))
    
    return render_template('create_profile.html')

@app.route('/profile/create/introduction', methods=['GET', 'POST'])
@login_required
def create_introduction():
    """Create introduction section"""
    form_data = {}
    form_errors = {}
    
    if request.method == 'POST':
        name = request.form.get('name', '').strip()
        email = request.form.get('email', '').strip()
        phone = request.form.get('phone', '').strip()
        linkedin = request.form.get('linkedin', '').strip()
        github = request.form.get('github', '').strip()
        website = request.form.get('website', '').strip()
        
        # Store form data
        form_data = {
            'name': name,
            'email': email,
            'phone': phone,
            'linkedin': linkedin,
            'github': github,
            'website': website
        }
        
        # Validation
        if not name:
            form_errors['name'] = ['Name is required']
        if not email:
            form_errors['email'] = ['Email is required']
        elif not re.match(r'^[^@]+@[^@]+\.[^@]+$', email):
            form_errors['email'] = ['Invalid email format']
        if not phone:
            form_errors['phone'] = ['Phone is required']
        
        if form_errors:
            return render_template('create_introduction.html', 
                                 form_data=form_data, 
                                 form_errors=form_errors)
        
        # Create introduction
        introduction = Introduction(
            user_id=current_user.id,
            name=name,
            email=email,
            phone=phone,
            linkedin=linkedin or None,
            github=github or None,
            website=website or None
        )
        
        try:
            db.session.add(introduction)
            db.session.commit()
            return redirect(url_for('create_profile_summary'))
        except Exception as e:
            db.session.rollback()
            flash('An error occurred while saving your introduction. Please try again.', 'error')
    
    return render_template('create_introduction.html', 
                         form_data=form_data, 
                         form_errors=form_errors)

@app.route('/profile/create/profile-summary', methods=['GET', 'POST'])
@login_required
def create_profile_summary():
    """Create profile summary section"""
    form_data = {}
    form_errors = {}
    
    if not current_user.introduction:
        flash('Please complete your introduction first.', 'error')
        return redirect(url_for('create_introduction'))
    
    if request.method == 'POST':
        summary = request.form.get('summary', '').strip()
        
        # Store form data
        form_data = {
            'summary': summary
        }
        
        # Validation
        if not summary:
            form_errors['summary'] = ['Profile summary is required']
        
        if form_errors:
            return render_template('create_profile_summary.html', 
                                 form_data=form_data, 
                                 form_errors=form_errors)
        
        # Create or update profile summary
        profile_summary = ProfileSummary.query.filter_by(user_id=current_user.id).first()
        if not profile_summary:
            profile_summary = ProfileSummary(user_id=current_user.id)
        
        profile_summary.summary = summary
        profile_summary.ai_generated = False
        
        try:
            db.session.add(profile_summary)
            db.session.commit()
            return redirect(url_for('create_work_experience'))
        except Exception as e:
            db.session.rollback()
            flash('An error occurred while saving your profile summary. Please try again.', 'error')
    
    # For GET request or if returning from POST with error
    # Get existing summary if any
    existing_summary = ProfileSummary.query.filter_by(user_id=current_user.id).first()
    if existing_summary:
        form_data['summary'] = existing_summary.summary
    
    return render_template('create_profile_summary.html', 
                         form_data=form_data, 
                         form_errors=form_errors)

@app.route('/profile/create/generate-summary', methods=['POST'])
@login_required
def generate_ai_summary():
    """Generate AI-powered profile summary using OpenAI"""
    if not current_user.introduction:
        return jsonify({'error': 'Please complete your introduction first'}), 400
    
    try:
        # Get user's introduction and other relevant info
        intro = current_user.introduction
        
        # Get additional profile data if available
        work_experiences = WorkExperience.query.filter_by(user_id=current_user.id).all()
        projects = Project.query.filter_by(user_id=current_user.id).all()
        educations = Education.query.filter_by(user_id=current_user.id).all()
        skills = Skill.query.filter_by(user_id=current_user.id).all()
        
        # Prepare context for AI
        context = f"""
        Personal Information:
        - Name: {intro.name}
        - Email: {intro.email}
        - Phone: {intro.phone}
        - LinkedIn: {intro.linkedin or 'Not provided'}
        - GitHub: {intro.github or 'Not provided'}
        - Website: {intro.website or 'Not provided'}
        """
        
        if work_experiences:
            context += "\n\nWork Experience:\n"
            for exp in work_experiences[:3]:  # Limit to first 3 experiences
                context += f"- {exp.title} at {exp.organization} ({exp.start_month}/{exp.start_year} - {'Present' if not exp.end_month else f'{exp.end_month}/{exp.end_year}'})\n"
        
        if educations:
            context += "\nEducation:\n"
            for edu in educations[:2]:  # Limit to first 2 educations
                context += f"- {edu.title} at {edu.organization} ({edu.start_month}/{edu.start_year} - {'Present' if not edu.end_month else f'{edu.end_month}/{edu.end_year}'})\n"
        
        if skills:
            skill_list = [s.skill for s in skills[:10]]  # Limit to first 10 skills
            context += f"\nSkills: {', '.join(skill_list)}"
        
        # Using OpenAI API directly
        def generate_with_openai():
            from openai import OpenAI
            client = OpenAI(api_key=os.environ.get('OPENAI_API_KEY'))
            
            prompt = f"""
            Create a professional profile summary based on this information:
            
            {context}
            
            Requirements:
            - Write in third person
            - Keep it concise (3-5 sentences)
            - Highlight professional strengths and achievements
            - Make it engaging and professional
            - Focus on what makes this person unique
            """
            
            response = client.chat.completions.create(
                model=os.environ.get('OPENAI_MODEL', 'gpt-4o'),
                messages=[
                    {"role": "system", "content": "You are an expert resume writer and career coach. Write compelling professional profiles that stand out."},
                    {"role": "user", "content": prompt}
                ],
                max_tokens=250,
                temperature=0.8
            )
            return response.choices[0].message.content.strip()
        
        # Generate the summary
        ai_summary = generate_with_openai()
        
        # Save the AI-generated summary
        profile_summary = ProfileSummary.query.filter_by(user_id=current_user.id).first()
        if not profile_summary:
            profile_summary = ProfileSummary(user_id=current_user.id)
        
        profile_summary.summary = ai_summary
        profile_summary.ai_generated = True
        
        db.session.add(profile_summary)
        db.session.commit()
        
        return jsonify({
            'success': True,
            'summary': ai_summary,
            'message': 'Profile summary generated successfully!'
        })
    
    except Exception as e:
        db.session.rollback()
        return jsonify({'success': False, 'error': f'Failed to generate summary: {str(e)}'}), 500

@app.route('/profile/create/work-experience', methods=['GET', 'POST'])
@login_required
def create_work_experience():
    """Create work experience section"""
    if not current_user.introduction:
        flash('Please complete your introduction first.', 'error')
        return redirect(url_for('create_introduction'))
    
    if request.method == 'POST':
        # Clear existing work experiences for this user
        WorkExperience.query.filter_by(user_id=current_user.id).delete()
        
        # Get form data
        organizations = request.form.getlist('organization[]')
        titles = request.form.getlist('title[]')
        start_months = request.form.getlist('start_month[]')
        start_years = request.form.getlist('start_year[]')
        end_months = request.form.getlist('end_month[]')
        end_years = request.form.getlist('end_year[]')
        is_present_list = request.form.getlist('is_present[]')
        remarks_list = request.form.getlist('remarks[]')
        
        # Find the maximum length among all lists to handle inconsistent lengths
        max_length = max(len(organizations), len(titles), len(start_months), 
                        len(start_years), len(end_months), len(end_years), 
                        len(remarks_list))
        
        # Save each work experience
        for i in range(max_length):
            org = organizations[i] if i < len(organizations) else ''
            title = titles[i] if i < len(titles) else ''
            
            if org.strip():  # Only save if organization is provided
                work_exp = WorkExperience(
                    user_id=current_user.id,
                    organization=org.strip(),
                    title=title.strip(),
                    start_month=int(start_months[i]) if i < len(start_months) and start_months[i] else None,
                    start_year=int(start_years[i]) if i < len(start_years) and start_years[i] else None,
                    end_month=int(end_months[i]) if i < len(end_months) and end_months[i] and str(i) not in is_present_list else None,
                    end_year=int(end_years[i]) if i < len(end_years) and end_years[i] and str(i) not in is_present_list else None,
                    remarks=remarks_list[i].strip() if i < len(remarks_list) and remarks_list[i] else None,
                    order=i
                )
                db.session.add(work_exp)
        
        try:
            db.session.commit()
            flash('Work experience saved successfully.', 'success')
            return redirect(url_for('create_projects'))
        except Exception as e:
            db.session.rollback()
            flash('An error occurred while saving work experience.', 'error')
    
    # GET request - show form
    form_data = {
        'work_experiences': WorkExperience.query.filter_by(user_id=current_user.id).order_by(WorkExperience.order).all()
    }
    
    return render_template('create_work_experience.html', 
                         form_data=form_data, 
                         current_year=datetime.now().year)

@app.route('/profile/create/projects', methods=['GET', 'POST'])
@login_required
def create_projects():
    """Create projects section"""
    if not current_user.introduction:
        flash('Please complete your introduction first.', 'error')
        return redirect(url_for('create_introduction'))
    
    if request.method == 'POST':
        # Clear existing projects for this user
        Project.query.filter_by(user_id=current_user.id).delete()
        
        # Get form data
        organizations = request.form.getlist('organization[]')
        titles = request.form.getlist('title[]')
        start_months = request.form.getlist('start_month[]')
        start_years = request.form.getlist('start_year[]')
        end_months = request.form.getlist('end_month[]')
        end_years = request.form.getlist('end_year[]')
        is_present_list = request.form.getlist('is_present[]')
        remarks_list = request.form.getlist('remarks[]')
        
        # Find the maximum length among all lists to handle inconsistent lengths
        max_length = max(len(organizations), len(titles), len(start_months), 
                        len(start_years), len(end_months), len(end_years), 
                        len(remarks_list))
        
        # Save each project
        for i in range(max_length):
            title = titles[i] if i < len(titles) else ''
            org = organizations[i] if i < len(organizations) else ''
            
            if title.strip():  # Only save if title is provided
                project = Project(
                    user_id=current_user.id,
                    organization=org.strip() if org else None,
                    title=title.strip(),
                    start_month=int(start_months[i]) if i < len(start_months) and start_months[i] else None,
                    start_year=int(start_years[i]) if i < len(start_years) and start_years[i] else None,
                    end_month=int(end_months[i]) if i < len(end_months) and end_months[i] and str(i) not in is_present_list else None,
                    end_year=int(end_years[i]) if i < len(end_years) and end_years[i] and str(i) not in is_present_list else None,
                    remarks=remarks_list[i].strip() if i < len(remarks_list) and remarks_list[i] else None,
                    order=i
                )
                db.session.add(project)
        
        try:
            db.session.commit()
            flash('Projects saved successfully.', 'success')
            return redirect(url_for('create_education'))
        except Exception as e:
            db.session.rollback()
            flash('An error occurred while saving projects.', 'error')
    
    # GET request - show form
    form_data = {
        'projects': Project.query.filter_by(user_id=current_user.id).order_by(Project.order).all()
    }
    
    return render_template('create_projects.html', 
                         form_data=form_data, 
                         current_year=datetime.now().year)

@app.route('/profile/create/education', methods=['GET', 'POST'])
@login_required
def create_education():
    """Create education section"""
    if not current_user.introduction:
        flash('Please complete your introduction first.', 'error')
        return redirect(url_for('create_introduction'))
    
    if request.method == 'POST':
        # Clear existing education for this user
        Education.query.filter_by(user_id=current_user.id).delete()
        
        # Get form data
        organizations = request.form.getlist('organization[]')
        titles = request.form.getlist('title[]')
        start_months = request.form.getlist('start_month[]')
        start_years = request.form.getlist('start_year[]')
        end_months = request.form.getlist('end_month[]')
        end_years = request.form.getlist('end_year[]')
        is_present_list = request.form.getlist('is_present[]')
        remarks_list = request.form.getlist('remarks[]')
        
        # Find the maximum length among all lists to handle inconsistent lengths
        max_length = max(len(organizations), len(titles), len(start_months), 
                        len(start_years), len(end_months), len(end_years), 
                        len(remarks_list))
        
        # Save each education
        for i in range(max_length):
            org = organizations[i] if i < len(organizations) else ''
            title = titles[i] if i < len(titles) else ''
            
            if org.strip():  # Only save if organization is provided
                education = Education(
                    user_id=current_user.id,
                    organization=org.strip(),
                    title=title.strip(),
                    start_month=int(start_months[i]) if i < len(start_months) and start_months[i] else None,
                    start_year=int(start_years[i]) if i < len(start_years) and start_years[i] else None,
                    end_month=int(end_months[i]) if i < len(end_months) and end_months[i] and str(i) not in is_present_list else None,
                    end_year=int(end_years[i]) if i < len(end_years) and end_years[i] and str(i) not in is_present_list else None,
                    remarks=remarks_list[i].strip() if i < len(remarks_list) and remarks_list[i] else None,
                    order=i
                )
                db.session.add(education)
        
        try:
            db.session.commit()
            flash('Education saved successfully.', 'success')
            return redirect(url_for('create_skills'))
        except Exception as e:
            db.session.rollback()
            flash('An error occurred while saving education.', 'error')
    
    # GET request - show form
    form_data = {
        'educations': Education.query.filter_by(user_id=current_user.id).order_by(Education.order).all()
    }
    
    return render_template('create_education.html', 
                         form_data=form_data, 
                         current_year=datetime.now().year)

@app.route('/profile/create/skills', methods=['GET', 'POST'])
@login_required
def create_skills():
    """Create skills section"""
    form_data = {}
    form_errors = {}
    
    if not current_user.introduction:
        flash('Please complete your introduction first.', 'error')
        return redirect(url_for('create_introduction'))
    
    if request.method == 'POST':
        # Get skills from form
        skills_text = request.form.get('skills', '').strip()
        
        # Store form data
        form_data = {
            'skills': skills_text,
            'skills_preview': [skill.strip() for skill in skills_text.split(',') if skill.strip()] if skills_text else []
        }
        
        # Validation - skills are optional but if provided, they should be valid
        if skills_text and len(skills_text.split(',')) > 50:
            form_errors['skills'] = ['You can add up to 50 skills maximum']
        
        if form_errors:
            return render_template('create_skills.html', 
                                 form_data=form_data, 
                                 form_errors=form_errors)
        
        # Clear existing skills for this user
        Skill.query.filter_by(user_id=current_user.id).delete()
        
        if skills_text:
            skills_list = [skill.strip() for skill in skills_text.split(',') if skill.strip()]
            
            # Save each skill
            for i, skill in enumerate(skills_list):
                new_skill = Skill(
                    user_id=current_user.id,
                    skill=skill,
                    order=i
                )
                db.session.add(new_skill)
        
        try:
            db.session.commit()
            flash('Skills saved successfully.', 'success')
            return redirect(url_for('create_achievements'))
        except Exception as e:
            db.session.rollback()
            flash('An error occurred while saving skills.', 'error')
    
    # GET request - show form
    existing_skills = Skill.query.filter_by(user_id=current_user.id).order_by(Skill.order).all()
    skills_text = ', '.join([skill.skill for skill in existing_skills])
    
    form_data = {
        'skills': skills_text,
        'skills_preview': [skill.skill for skill in existing_skills]
    }
    
    return render_template('create_skills.html', 
                         form_data=form_data, 
                         form_errors=form_errors)

@app.route('/profile/create/achievements', methods=['GET', 'POST'])
@login_required
def create_achievements():
    """Create achievements section"""
    form_data = {}
    form_errors = {}
    
    if not current_user.introduction:
        flash('Please complete your introduction first.', 'error')
        return redirect(url_for('create_introduction'))
    
    if request.method == 'POST':
        # Get achievements from form
        achievements_text = request.form.get('achievements', '').strip()
        
        # Store form data
        form_data = {
            'achievements': achievements_text,
            'achievements_preview': [achievement.strip() for achievement in achievements_text.split(',') if achievement.strip()] if achievements_text else []
        }
        
        # Validation - achievements are optional but if provided, they should be valid
        if achievements_text and len(achievements_text.split(',')) > 50:
            form_errors['achievements'] = ['You can add up to 50 achievements maximum']
        
        if form_errors:
            return render_template('create_achievements.html', 
                                 form_data=form_data, 
                                 form_errors=form_errors)
        
        # Clear existing achievements for this user
        Achievement.query.filter_by(user_id=current_user.id).delete()
        
        if achievements_text:
            achievements_list = [achievement.strip() for achievement in achievements_text.split(',') if achievement.strip()]
            
            # Save each achievement
            for i, achievement in enumerate(achievements_list):
                new_achievement = Achievement(
                    user_id=current_user.id,
                    achievement=achievement,
                    order=i
                )
                db.session.add(new_achievement)
        
        try:
            db.session.commit()
            flash('Achievements saved successfully.', 'success')
            return redirect(url_for('create_preview'))
        except Exception as e:
            db.session.rollback()
            flash('An error occurred while saving achievements.', 'error')
    
    # GET request - show form
    existing_achievements = Achievement.query.filter_by(user_id=current_user.id).order_by(Achievement.order).all()
    achievements_text = ', '.join([achievement.achievement for achievement in existing_achievements])
    
    form_data = {
        'achievements': achievements_text,
        'achievements_preview': [achievement.achievement for achievement in existing_achievements]
    }
    
    return render_template('create_achievements.html', 
                         form_data=form_data, 
                         form_errors=form_errors)

@app.route('/profile/create/preview', methods=['GET', 'POST'])
@login_required
def create_preview():
    """Preview and finalize profile"""
    if not current_user.introduction:
        flash('Please complete your introduction first.', 'error')
        return redirect(url_for('create_introduction'))
    
    if request.method == 'POST':
        action = request.form.get('action')
        
        if action == 'submit':
            # Save section order
            section_order = request.form.get('section_order', '[]')
            try:
                order_data = json.loads(section_order)
                
                # Update or create section order
                profile_order = ProfileSectionOrder.query.filter_by(user_id=current_user.id).first()
                if not profile_order:
                    profile_order = ProfileSectionOrder(user_id=current_user.id)
                
                profile_order.section_order = order_data
                db.session.add(profile_order)
                db.session.commit()
                
                flash('Profile created successfully!', 'success')
                return redirect(url_for('profile'))
            
            except Exception as e:
                db.session.rollback()
                flash('An error occurred while saving your profile.', 'error')
        
        elif action == 'clear':
            # Delete all profile data
            try:
                # Delete all profile sections
                if current_user.introduction:
                    db.session.delete(current_user.introduction)
                if current_user.profile_summary:
                    db.session.delete(current_user.profile_summary)
                if current_user.section_order:
                    db.session.delete(current_user.section_order)
                
                # Delete collections
                WorkExperience.query.filter_by(user_id=current_user.id).delete()
                Project.query.filter_by(user_id=current_user.id).delete()
                Education.query.filter_by(user_id=current_user.id).delete()
                Skill.query.filter_by(user_id=current_user.id).delete()
                Achievement.query.filter_by(user_id=current_user.id).delete()
                
                db.session.commit()
                flash('Profile cleared successfully.', 'success')
                return redirect(url_for('profile'))
            
            except Exception as e:
                db.session.rollback()
                flash('An error occurred while clearing your profile.', 'error')
    
    # Get all profile data
    intro = current_user.introduction
    summary = current_user.profile_summary
    work_experiences = WorkExperience.query.filter_by(user_id=current_user.id).order_by(WorkExperience.order).all()
    projects = Project.query.filter_by(user_id=current_user.id).order_by(Project.order).all()
    educations = Education.query.filter_by(user_id=current_user.id).order_by(Education.order).all()
    skills = Skill.query.filter_by(user_id=current_user.id).order_by(Skill.order).all()
    achievements = Achievement.query.filter_by(user_id=current_user.id).order_by(Achievement.order).all()
    
    # Get default section order
    default_order = ['introduction', 'profile_summary', 'work_experience', 'projects', 'education', 'skills', 'achievements']
    
    return render_template('create_preview.html',
                         intro=intro,
                         summary=summary,
                         work_experiences=work_experiences,
                         projects=projects,
                         educations=educations,
                         skills=skills,
                         achievements=achievements,
                         default_order=default_order)

@app.route('/ping')
def ping():
    return {"ok": True, "msg": "pong from app.py"}

@app.cli.command()
def create_tables():
    """Create database tables"""
    with app.app_context():
        db.create_all()
        print("Database tables created successfully!")

# Resume Generation Routes
@app.route('/profile/generate-resume/<format_type>')
@login_required
def generate_resume(format_type):
    """Generate resume in specified format"""
    # Check if user has profile data
    intro = Introduction.query.filter_by(user_id=current_user.id).first()
    if not intro:
        flash('Please create your profile first.', 'error')
        return redirect(url_for('profile'))
    
    # Get all profile data
    summary = ProfileSummary.query.filter_by(user_id=current_user.id).first()
    work_experiences = WorkExperience.query.filter_by(user_id=current_user.id).order_by(WorkExperience.order).all()
    projects = Project.query.filter_by(user_id=current_user.id).order_by(Project.order).all()
    educations = Education.query.filter_by(user_id=current_user.id).order_by(Education.order).all()
    skills = Skill.query.filter_by(user_id=current_user.id).order_by(Skill.order).all()
    achievements = Achievement.query.filter_by(user_id=current_user.id).order_by(Achievement.order).all()
    
    # Get section order
    section_order_obj = ProfileSectionOrder.query.filter_by(user_id=current_user.id).first()
    section_order = section_order_obj.section_order if section_order_obj else [
        'introduction', 'profile_summary', 'work_experience', 
        'projects', 'education', 'skills', 'achievements'
    ]
    
    try:
        if format_type == 'word':
            return generate_word_resume(
                intro, summary, work_experiences, projects, 
                educations, skills, achievements, section_order
            )
        elif format_type == 'pdf-standard':
            return generate_pdf_resume(
                intro, summary, work_experiences, projects, 
                educations, skills, achievements, section_order, 'standard'
            )
        elif format_type == 'pdf-modern':
            return generate_pdf_resume(
                intro, summary, work_experiences, projects, 
                educations, skills, achievements, section_order, 'modern'
            )
        else:
            flash('Invalid resume format.', 'error')
            return redirect(url_for('profile'))
    
    except Exception as e:
        import traceback
        app.logger.error(f"Error generating resume: {str(e)}")
        app.logger.error(traceback.format_exc())
        flash(f'An error occurred while generating your resume: {str(e)}', 'error')
        return redirect(url_for('profile'))

def generate_word_resume(intro, summary, work_experiences, projects, educations, skills, achievements, section_order):
    """Generate Word document resume"""
    try:
        from docx import Document
        from docx.shared import Pt, Inches, RGBColor
        from docx.enum.text import WD_ALIGN_PARAGRAPH
        
        # Create document
        doc = Document()
        
        # Set default font
        style = doc.styles['Normal']
        font = style.font
        font.name = 'Calibri'
        font.size = Pt(11)
        
            # Header section
        name_para = doc.add_paragraph()
        name_para.alignment = WD_ALIGN_PARAGRAPH.CENTER
        name_run = name_para.add_run(intro.name.upper())
        name_run.bold = True
        name_run.size = Pt(16)
        
        # Contact info
        contact_para = doc.add_paragraph()
        contact_para.alignment = WD_ALIGN_PARAGRAPH.CENTER
        contact_para.add_run(f"Email: {intro.email} | Phone: {intro.phone}")
        if intro.linkedin:
            contact_para.add_run(" | LinkedIn")
        if intro.github:
            contact_para.add_run(" | GitHub")
        if intro.website:
            contact_para.add_run(" | Website")
        
        doc.add_paragraph()
        
        # Profile summary
        if summary:
            doc.add_heading('Professional Summary', level=1)
            summary_para = doc.add_paragraph(summary.summary)
            if summary.ai_generated:
                ai_para = doc.add_paragraph("AI Generated")
                ai_para.italic = True
                ai_para.runs[0].font.size = Pt(9)
            doc.add_paragraph()
        
            for section_name in section_order:
                if section_name == 'work_experience' and work_experiences:
                    doc.add_heading('Work Experience', level=1)
                    for exp in work_experiences:
                        # Title and organization
                        exp_para = doc.add_paragraph()
                        exp_para.add_run(exp.title).bold = True
                        exp_para.add_run(f" at {exp.organization}").italic = True
                        
                        # Date
                        date_para = doc.add_paragraph()
                        date_text = f"{exp.start_month}/{exp.start_year} - "
                        if exp.end_year:
                            date_text += f"{exp.end_month}/{exp.end_year}"
                        else:
                            date_text += "Present"
                        date_para.add_run(date_text)
                        
                        # Remarks
                        if exp.remarks:
                            remarks_para = doc.add_paragraph(exp.remarks)
                        
                        doc.add_paragraph()
            
                elif section_name == 'projects' and projects:
                    doc.add_heading('Projects', level=1)
                    for project in projects:
                        # Title and organization
                        proj_para = doc.add_paragraph()
                        proj_para.add_run(project.title).bold = True
                        if project.organization:
                            proj_para.add_run(f" at {project.organization}").italic = True
                        
                        # Date
                        date_para = doc.add_paragraph()
                        date_text = f"{project.start_month}/{project.start_year} - "
                        if project.end_year:
                            date_text += f"{project.end_month}/{project.end_year}"
                        else:
                            date_text += "Present"
                        date_para.add_run(date_text)
                        
                        # Remarks
                        if project.remarks:
                            remarks_para = doc.add_paragraph(project.remarks)
                        
                        doc.add_paragraph()
            
                elif section_name == 'education' and educations:
                    doc.add_heading('Education', level=1)
                    for edu in educations:
                        # Title and organization
                        edu_para = doc.add_paragraph()
                        edu_para.add_run(edu.title).bold = True
                        edu_para.add_run(f" at {edu.organization}").italic = True
                        
                        # Date
                        date_para = doc.add_paragraph()
                        date_text = f"{edu.start_month}/{edu.start_year} - "
                        if edu.end_year:
                            date_text += f"{edu.end_month}/{edu.end_year}"
                        else:
                            date_text += "Present"
                        date_para.add_run(date_text)
                        
                        # Remarks
                        if edu.remarks:
                            remarks_para = doc.add_paragraph(edu.remarks)
                        
                        doc.add_paragraph()
            
                elif section_name == 'skills' and skills:
                    doc.add_heading('Skills', level=1)
                    skills_text = ", ".join([skill.skill for skill in skills])
                    doc.add_paragraph(skills_text)
                    doc.add_paragraph()
            
                elif section_name == 'achievements' and achievements:
                    doc.add_heading('Achievements', level=1)
                    for achievement in achievements:
                        doc.add_paragraph(f"• {achievement.achievement}")
                    doc.add_paragraph()
        
        # Save to bytes
        from io import BytesIO
        doc_buffer = BytesIO()
        doc.save(doc_buffer)
        doc_buffer.seek(0)
        
        # Return as downloadable file
        username = intro.name.replace(' ', '_')
        return send_file(
            doc_buffer,
            mimetype='application/vnd.openxmlformats-officedocument.wordprocessingml.document',
            as_attachment=True,
            download_name=f'{username}_resume.docx'
        )
    
    except Exception as e:
        app.logger.error(f"Error generating Word resume: {str(e)}")
        raise

def generate_pdf_resume(intro, summary, work_experiences, projects, educations, skills, achievements, section_order, template_type):
    """Generate PDF resume using ReportLab"""
    try:
        from pdf_generator import create_pdf_resume
        from io import BytesIO
        import calendar
        
        def format_date(month, year):
            """Format month and year as 'Month Year'"""
            if month and year:
                try:
                    month_name = calendar.month_name[int(month)]
                    return f"{month_name[:3]} {year}"
                except:
                    return f"{month}/{year}"
            return ""
        
        # Prepare data for PDF generation
        work_exp_list = []
        if work_experiences:
            for exp in work_experiences:
                start_date = format_date(exp.start_month, exp.start_year)
                end_date = "Present" if not exp.end_month or not exp.end_year else format_date(exp.end_month, exp.end_year)
                
                work_exp_list.append({
                    'title': exp.title,
                    'organization': exp.organization,
                    'start_date': start_date,
                    'end_date': end_date,
                    'remarks': exp.remarks or ''
                })
        
        projects_list = []
        if projects:
            for proj in projects:
                start_date = format_date(proj.start_month, proj.start_year)
                end_date = "Present" if not proj.end_month or not proj.end_year else format_date(proj.end_month, proj.end_year)
                
                projects_list.append({
                    'title': proj.title,
                    'organization': proj.organization,
                    'start_date': start_date,
                    'end_date': end_date,
                    'remarks': proj.remarks or ''
                })
        
        education_list = []
        if educations:
            for edu in educations:
                start_date = format_date(edu.start_month, edu.start_year)
                end_date = "Present" if not edu.end_month or not edu.end_year else format_date(edu.end_month, edu.end_year)
                
                education_list.append({
                    'title': edu.title,
                    'organization': edu.organization,
                    'start_date': start_date,
                    'end_date': end_date,
                    'remarks': edu.remarks or ''
                })
        
        # Convert skills and achievements to comma-separated strings
        skills_text = ', '.join([skill.skill for skill in skills]) if skills else ''
        achievements_text = ', '.join([achievement.achievement for achievement in achievements]) if achievements else ''
        
        # Create data dictionary
        data = {
            'name': intro.name,
            'email': intro.email,
            'phone': intro.phone,
            'linkedin': intro.linkedin,
            'github': intro.github,
            'website': intro.website,
            'summary': summary.summary if summary else '',
            'work_experience': work_exp_list,
            'projects': projects_list,
            'education': education_list,
            'skills': skills_text,
            'achievements': achievements_text,
            'sections_order': section_order
        }
        
        # Generate PDF
        pdf_bytes = create_pdf_resume(data, template_type)
        
        if pdf_bytes:
            # Return as downloadable file
            username = intro.name.replace(' ', '_')
            filename = f'{username}_resume.pdf' if template_type == 'standard' else f'{username}_resume_modern.pdf'
            
            pdf_buffer = BytesIO(pdf_bytes)
            
            return send_file(
                pdf_buffer,
                mimetype='application/pdf',
                as_attachment=True,
                download_name=filename
            )
        else:
            raise Exception("PDF generation failed")
            
    except Exception as e:
        app.logger.error(f"Error generating PDF resume: {str(e)}")
        raise

# Admin Panel Route
@app.route('/admin')
@admin_required
def admin_panel():
    """Admin panel to manage users"""
    users = User.query.order_by(User.created_at.desc()).all()
    return render_template('admin.html', users=users)

# Admin API Endpoints
@app.route('/api/admin/users', methods=['GET'])
@admin_required
def api_get_users():
    """Get list of all users"""
    try:
        users = User.query.order_by(User.created_at.desc()).all()
        users_data = []
        
        for user in users:
            users_data.append({
                'id': str(user.id),
                'email': user.email,
                'name': user.name,
                'created_at': user.created_at.isoformat() if user.created_at else None,
                'is_admin': user.is_admin,
                'role': user.role
            })
        
        return jsonify({
            'success': True,
            'users': users_data
        })
    except Exception as e:
        app.logger.error(f"Error fetching users: {str(e)}")
        return jsonify({
            'success': False,
            'error': str(e)
        }), 500

@app.route('/api/admin/users/<user_id>', methods=['DELETE'])
@admin_required
def api_delete_user(user_id):
    """Delete a user and all their profile data"""
    try:
        # Find the user and store email before deletion
        user = User.query.get(user_id)
        if not user:
            return jsonify({
                'success': False,
                'error': 'User not found'
            }), 404
        
        # Store user email for success message
        user_email = user.email
        
        # Don't allow deleting admin users
        if user.is_admin:
            return jsonify({
                'success': False,
                'error': 'Cannot delete admin users'
            }), 400
        
        # Don't allow deleting self
        if str(user.id) == str(current_user.id):
            return jsonify({
                'success': False,
                'error': 'Cannot delete your own account'
            }), 400
        
        # Use direct SQL to delete all profile data first
        # This ensures we handle any duplicate data that might exist
        
        # Delete from all profile tables
        from sqlalchemy import text
        
        # Delete introductions (handle potential duplicates)
        db.session.execute(text("DELETE FROM introductions WHERE user_id = :user_id"), {'user_id': str(user_id)})
        
        # Delete profile summaries
        db.session.execute(text("DELETE FROM profile_summaries WHERE user_id = :user_id"), {'user_id': str(user_id)})
        
        # Delete work experiences
        db.session.execute(text("DELETE FROM work_experiences WHERE user_id = :user_id"), {'user_id': str(user_id)})
        
        # Delete projects
        db.session.execute(text("DELETE FROM projects WHERE user_id = :user_id"), {'user_id': str(user_id)})
        
        # Delete education
        db.session.execute(text("DELETE FROM educations WHERE user_id = :user_id"), {'user_id': str(user_id)})
        
        # Delete skills
        db.session.execute(text("DELETE FROM skills WHERE user_id = :user_id"), {'user_id': str(user_id)})
        
        # Delete achievements
        db.session.execute(text("DELETE FROM achievements WHERE user_id = :user_id"), {'user_id': str(user_id)})
        
        # Delete section order
        db.session.execute(text("DELETE FROM profile_section_orders WHERE user_id = :user_id"), {'user_id': str(user_id)})
        
        # Finally delete the user
        db.session.execute(text("DELETE FROM users WHERE id = :user_id"), {'user_id': str(user_id)})
        
        # Expunge the user object from session to avoid the deleted instance warning
        db.session.expunge(user)
        
        db.session.commit()
        
        return jsonify({
            'success': True,
            'message': f'User {user_email} and all their profile data have been deleted successfully'
        })
        
    except Exception as e:
        db.session.rollback()
        app.logger.error(f"Error deleting user: {str(e)}")
        return jsonify({
            'success': False,
            'error': str(e)
        }), 500

def create_tables_if_needed():
    """Create database tables if they don't exist"""
    with app.app_context():
        # Check if tables exist
        inspector = db.inspect(db.engine)
        table_names = inspector.get_table_names()
        
        if not table_names or 'users' not in table_names:
            print("Creating database tables...")
            db.create_all()
            print("Database tables created successfully!")
            
            # Run admin migration if needed
            try:
                from sqlalchemy import text
                columns = [column['name'] for column in inspector.get_columns('users')]
                if 'is_admin' not in columns:
                    print("Running admin migration...")
                    db.session.execute(text('ALTER TABLE users ADD COLUMN is_admin BOOLEAN DEFAULT FALSE'))
                    db.session.execute(text('ALTER TABLE users ADD COLUMN role VARCHAR(50) DEFAULT \'User\''))
                    db.session.commit()
                    print("Admin migration completed!")
            except Exception as e:
                print(f"Migration error: {e}")

# Initialize database only when running directly, not when imported
if __name__ == "__main__":
    create_tables_if_needed()
    port = int(os.environ.get('PORT', 5000))
    # Railway requires binding to 0.0.0.0
    # Check if we're running on Railway
    is_railway = os.environ.get('RAILWAY_ENVIRONMENT') or os.environ.get('RAILWAY_ENVIRONMENT_NAME')
    host = '0.0.0.0' if is_railway else '127.0.0.1'
    print(f"Flask running at http://{host}:{port}")
    # Disable debug mode in production
    debug = not is_railway
    app.run(host=host, port=port, debug=debug)