"""
Advanced Load Testing Script - End-to-End Assessment Flow

World-class load testing with:
- Smart browser management (prevents system crashes)
- Progress persistence (resume from checkpoint)
- Real-time performance tracking
- Lightweight metrics collection
- Advanced error handling

Usage:
    python scripts/load_test_e2e_assessment_advanced.py --students 100 --csv students.csv

Features:
- Progress persistence (save every N students)
- Resume capability (skip completed students)
- Real-time metrics dashboard
- Smart browser limiting (visible mode)
- Performance analytics
- Resource monitoring
"""
import sys
import argparse
import csv
import json
import time
import threading
from pathlib import Path
from datetime import datetime
from concurrent.futures import ThreadPoolExecutor, as_completed
from typing import Dict, List, Optional
from collections import defaultdict

# Add project root to path
sys.path.insert(0, str(Path(__file__).parent.parent))

from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from selenium.webdriver.chrome.options import Options
from selenium.common.exceptions import WebDriverException, TimeoutException

from pages.login_page import LoginPage
from pages.mandatory_reset_page import MandatoryResetPage
from pages.profile_incomplete_page import ProfileIncompletePage
from pages.profile_editor_page import ProfileEditorPage
from pages.assessments_page import AssessmentsPage
from pages.domains_page import DomainsPage
from pages.domain_assessment_page import DomainAssessmentPage
from pages.domain_feedback_page import DomainFeedbackPage
from utils.question_answer_helper import QuestionAnswerHelper
from utils.password_tracker import password_tracker
from utils.student_data_manager import student_data_manager
from utils.smart_wait_optimizer import SmartWaitOptimizer
from utils.randomized_wait import RandomizedWait
from utils.wait_helpers import WaitHelpers
from config.config import BASE_URL, TEST_NEW_PASSWORD

# Global tracking with locks
results_lock = threading.Lock()
progress_lock = threading.Lock()

results = {
    'total': 0,
    'success': 0,
    'failed': 0,
    'skipped': 0,
    'errors': [],
    'start_time': None,
    'last_update': None
}

# Performance metrics
performance_metrics = {
    'step_times': defaultdict(list),  # step -> [durations]
    'total_durations': [],
    'questions_answered': [],
    'step_success_rates': defaultdict(lambda: {'success': 0, 'failed': 0})
}

# Progress file
PROGRESS_FILE = Path(__file__).parent.parent / "reports" / "load_test_progress.json"
PROGRESS_FILE.parent.mkdir(parents=True, exist_ok=True)

# Track completed students
completed_students = set()


class ProgressTracker:
    """Lightweight progress tracking and persistence"""
    
    @staticmethod
    def save_progress():
        """Save current progress to file"""
        with progress_lock:
            progress_data = {
                'timestamp': datetime.now().isoformat(),
                'results': results.copy(),
                'performance': {
                    'step_times': {k: v[-100:] for k, v in performance_metrics['step_times'].items()},  # Last 100
                    'total_durations': performance_metrics['total_durations'][-100:],  # Last 100
                    'questions_answered': performance_metrics['questions_answered'][-100:],  # Last 100
                    'step_success_rates': dict(performance_metrics['step_success_rates'])
                },
                'completed_students': ProgressTracker.get_completed_students()
            }
            
            try:
                with open(PROGRESS_FILE, 'w') as f:
                    json.dump(progress_data, f, indent=2)
            except Exception as e:
                print(f"⚠️  Error saving progress: {e}")
    
    @staticmethod
    def load_progress() -> Dict:
        """Load previous progress from file"""
        if not PROGRESS_FILE.exists():
            return {}
        
        try:
            with open(PROGRESS_FILE, 'r') as f:
                return json.load(f)
        except Exception as e:
            print(f"⚠️  Error loading progress: {e}")
            return {}
    
    @staticmethod
    def get_completed_students() -> List[str]:
        """Get list of completed student CPIDs"""
        return list(completed_students)
    
    @staticmethod
    def print_real_time_metrics():
        """Print real-time performance metrics"""
        with progress_lock:
            if results['total'] == 0:
                return
            
            print("\n" + "=" * 80)
            print("📊 REAL-TIME METRICS")
            print("=" * 80)
            
            # Overall stats
            success_rate = (results['success'] / results['total']) * 100 if results['total'] > 0 else 0
            print(f"✅ Success Rate: {success_rate:.1f}% ({results['success']}/{results['total']})")
            
            # Average durations
            if performance_metrics['total_durations']:
                avg_duration = sum(performance_metrics['total_durations']) / len(performance_metrics['total_durations'])
                print(f"⏱️  Average Duration: {avg_duration:.2f}s")
            
            # Step performance
            print("\n📈 Step Performance:")
            for step, times in performance_metrics['step_times'].items():
                if times:
                    avg_time = sum(times) / len(times)
                    success_rate = performance_metrics['step_success_rates'][step]
                    total_attempts = success_rate['success'] + success_rate['failed']
                    rate = (success_rate['success'] / total_attempts * 100) if total_attempts > 0 else 0
                    print(f"   {step}: {avg_time:.2f}s avg, {rate:.1f}% success ({success_rate['success']}/{total_attempts})")
            
            # Questions answered
            if performance_metrics['questions_answered']:
                avg_questions = sum(performance_metrics['questions_answered']) / len(performance_metrics['questions_answered'])
                print(f"\n❓ Average Questions Answered: {avg_questions:.1f}")
            
            # Estimated time remaining
            if results['total'] > 0 and results['start_time']:
                elapsed = time.time() - results['start_time']
                rate = results['total'] / elapsed if elapsed > 0 else 0
                print(f"\n⚡ Rate: {rate:.2f} students/second")
            
            print("=" * 80)


class LoadTestStudent:
    """Handles end-to-end flow for a single student with performance tracking"""
    
    def __init__(self, cpid: str, student_data: Dict, headless: bool = True):
        self.cpid = cpid
        self.student_data = student_data
        self.headless = headless
        self.driver = None
        self.step_times = {}
        self.actual_password_used = None  # Track which password was actually used for login
        self.result = {
            'cpid': cpid,
            'name': f"{student_data.get('First Name', '')} {student_data.get('Last Name', '')}",
            'status': 'pending',
            'steps_completed': [],
            'step_times': {},
            'error': None,
            'duration': 0,
            'questions_answered': 0
        }
    
    def _track_step(self, step_name: str, func):
        """Track step execution time and success/failure"""
        start_time = time.time()
        try:
            result = func()
            duration = time.time() - start_time
            
            self.step_times[step_name] = duration
            self.result['step_times'][step_name] = duration
            
            # Update global metrics
            with progress_lock:
                performance_metrics['step_times'][step_name].append(duration)
                if result:
                    performance_metrics['step_success_rates'][step_name]['success'] += 1
                else:
                    performance_metrics['step_success_rates'][step_name]['failed'] += 1
            
            return result
        except Exception as e:
            duration = time.time() - start_time
            self.step_times[step_name] = duration
            
            with progress_lock:
                performance_metrics['step_times'][step_name].append(duration)
                performance_metrics['step_success_rates'][step_name]['failed'] += 1
            
            raise
    
    def setup_driver(self, max_retries=3):
        """Create and configure WebDriver with retry logic for high concurrency"""
        options = Options()
        if self.headless:
            options.add_argument('--headless=new')
        options.add_argument('--no-sandbox')
        options.add_argument('--disable-dev-shm-usage')
        options.add_argument('--disable-gpu')
        options.add_argument('--window-size=1920,1080')
        # Additional stability options for high concurrency
        options.add_argument('--disable-software-rasterizer')
        options.add_argument('--disable-extensions')
        options.add_argument('--disable-background-networking')
        options.add_argument('--disable-sync')
        options.add_argument('--disable-default-apps')
        options.add_argument('--disable-background-timer-throttling')
        options.add_argument('--disable-renderer-backgrounding')
        options.add_argument('--disable-backgrounding-occluded-windows')
        
        for attempt in range(max_retries):
            try:
                self.driver = webdriver.Chrome(options=options)
                self.driver.implicitly_wait(5)
                return True
            except Exception as e:
                if attempt < max_retries - 1:
                    time.sleep(2)  # Wait before retry (longer for resource contention)
                    continue
                self.result['error'] = f"Driver setup failed after {max_retries} attempts: {str(e)[:200]}"
                return False
    
    def step_login(self) -> bool:
        """Step 1: Login with smart password handling"""
        return self._track_step('login', lambda: self._do_login())
    
    def _do_login(self) -> bool:
        """
        Login with explicit password strategy:
        1. Try Excel password FIRST (from CSV)
        2. If fails, fallback to Admin@123 (TEST_NEW_PASSWORD)
        """
        login_page = LoginPage(self.driver)
        login_page.navigate()
        
        # Get Excel password from student data
        excel_password = self.student_data.get('password')
        
        if not excel_password:
            # No password in CSV - use Admin@123 directly
            print(f"⚠️  No Excel password found for {self.cpid}, using Admin@123")
            excel_password = TEST_NEW_PASSWORD
        
        # Strategy: Try Excel password first, then Admin@123
        print(f"🔑 Trying Excel password first for {self.cpid}")
        
        # Try Excel password first
        login_page.enter_identifier(self.cpid)
        login_page.enter_password(excel_password)
        login_page.click_submit()
        
        # Wait for result
        from selenium.webdriver.support.ui import WebDriverWait
        from selenium.webdriver.support import expected_conditions as EC
        from config.config import SHORT_WAIT, BASE_URL, MEDIUM_WAIT
        from selenium.webdriver.common.by import By
        import time
        
        # Wait for navigation or error
        try:
            WebDriverWait(self.driver, MEDIUM_WAIT).until(
                lambda d: "/dashboard" in d.current_url 
                or "/student" in d.current_url 
                or "mandatory_reset" in d.page_source.lower()
                or login_page.is_error_visible()
            )
        except:
            pass
        
        current_url = self.driver.current_url
        is_on_login_page = (
            current_url.rstrip("/") == BASE_URL.rstrip("/") or 
            current_url.rstrip("/") == f"{BASE_URL}/" or
            "login" in current_url.lower()
        )
        
        # Determine which password was actually used
        actual_password_used = excel_password
        
        # If still on login page, Excel password failed - try Admin@123
        if is_on_login_page and login_page.is_error_visible():
            print(f"🔄 Excel password failed, trying Admin@123 (reset password)...")
            # Clear form and retry with Admin@123
            login_page.enter_identifier(self.cpid)
            login_page.enter_password(TEST_NEW_PASSWORD)
            login_page.click_submit()
            
            # Wait for navigation or error
            try:
                WebDriverWait(self.driver, MEDIUM_WAIT).until(
                    lambda d: "/dashboard" in d.current_url 
                    or "/student" in d.current_url 
                    or "mandatory_reset" in d.page_source.lower()
                    or login_page.is_error_visible()
                )
            except:
                pass
            
            # Check if Admin@123 worked
            current_url = self.driver.current_url
            is_still_on_login = (
                current_url.rstrip("/") == BASE_URL.rstrip("/") or 
                current_url.rstrip("/") == f"{BASE_URL}/" or
                "login" in current_url.lower()
            )
            
            if is_still_on_login and login_page.is_error_visible():
                # Both passwords failed
                error_msg = login_page.get_error_message()
                raise Exception(f"Login failed with both passwords. Excel password: {excel_password}, Admin@123: {TEST_NEW_PASSWORD}. Error: {error_msg}")
            else:
                # Admin@123 worked
                actual_password_used = TEST_NEW_PASSWORD
        
        # Store which password was actually used (for password reset step)
        self.actual_password_used = actual_password_used
        
        # Update password tracker if Admin@123 was used
        if actual_password_used == TEST_NEW_PASSWORD:
            password_tracker.update_password(self.cpid, TEST_NEW_PASSWORD)
        
        SmartWaitOptimizer.smart_wait_for_dashboard(self.driver, self.cpid, actual_password_used)
        
        self.result['steps_completed'].append('login')
        return True
    
    def step_password_reset(self) -> bool:
        """Step 2: Reset password if needed"""
        return self._track_step('password_reset', lambda: self._do_password_reset())
    
    def _do_password_reset(self) -> bool:
        """
        Reset password if needed.
        Uses the password that was actually used during login.
        """
        reset_page = MandatoryResetPage(self.driver)
        
        # Use the password that was actually used during login
        # If Admin@123 was used, password is already reset - skip
        if self.actual_password_used == TEST_NEW_PASSWORD:
            # Password already reset (Admin@123 worked) - skip reset
            self.result['steps_completed'].append('password_reset_skipped')
            return True
        
        # Excel password was used - check if reset is needed
        if SmartWaitOptimizer.should_check_password_reset(self.cpid, self.actual_password_used):
            if reset_page.is_modal_present():
                # Use Excel password (the one that worked) for reset
                current_password = self.actual_password_used or self.student_data.get('password')
                reset_page.reset_password(
                    current_password=current_password,
                    new_password=TEST_NEW_PASSWORD,
                    confirm_password=TEST_NEW_PASSWORD,
                    student_cpid=self.cpid
                )
                # Update password tracker
                password_tracker.update_password(self.cpid, TEST_NEW_PASSWORD)
                time.sleep(SmartWaitOptimizer.ANIMATION_NORMAL + SmartWaitOptimizer.SAFETY_PADDING)
                self.result['steps_completed'].append('password_reset')
            else:
                self.result['steps_completed'].append('password_reset_skipped')
        else:
            self.result['steps_completed'].append('password_reset_skipped')
        
        return True
    
    def step_profile_completion(self) -> bool:
        """Step 3: Complete profile if needed"""
        return self._track_step('profile_completion', lambda: self._do_profile_completion())
    
    def _do_profile_completion(self) -> bool:
        profile_incomplete = ProfileIncompletePage(self.driver)
        
        if SmartWaitOptimizer.should_check_profile_incomplete(self.driver):
            if profile_incomplete.is_modal_present():
                profile_incomplete.click_complete()
                time.sleep(SmartWaitOptimizer.ANIMATION_NORMAL + SmartWaitOptimizer.SAFETY_PADDING)
                
                profile_editor = ProfileEditorPage(self.driver)
                profile_editor.wait_for_page_load()
                profile_editor.complete_profile_to_100(student_cpid=self.cpid)
                time.sleep(SmartWaitOptimizer.ANIMATION_NORMAL + SmartWaitOptimizer.SAFETY_PADDING)
                self.result['steps_completed'].append('profile_completion')
            else:
                self.result['steps_completed'].append('profile_completion_skipped')
        else:
            self.result['steps_completed'].append('profile_completion_skipped')
        
        return True
    
    def step_complete_domain_assessment(self) -> bool:
        """Step 4: Complete ONE domain assessment"""
        return self._track_step('domain_assessment', lambda: self._do_domain_assessment())
    
    def _do_domain_assessment(self) -> bool:
        # Navigate to assessments
        assessments_page = AssessmentsPage(self.driver)
        assessments_page.navigate()
        assessments_page.wait_for_page_load()
        RandomizedWait.wait_for_page_load('navigation')
        
        # Get first assessment
        assessment_ids = assessments_page.get_assessment_ids()
        if not assessment_ids:
            raise Exception("No assessments available")
        
        assessments_page.click_begin_assessment(assessment_ids[0])
        RandomizedWait.wait_for_page_load('navigation')
        
        # Navigate to domains
        domains_page = DomainsPage(self.driver)
        domains_page.wait_for_page_load()
        RandomizedWait.wait_for_page_load('initial')
        
        # Get first unlocked domain
        domain_ids = domains_page.get_all_domain_ids()
        if not domain_ids:
            raise Exception("No domains available")
        
        unlocked_domain_id = None
        for domain_id in domain_ids:
            if domains_page.is_domain_unlocked(domain_id):
                unlocked_domain_id = domain_id
                break
        
        if not unlocked_domain_id:
            raise Exception("No unlocked domains available")
        
        domains_page.click_start_domain(unlocked_domain_id)
        RandomizedWait.wait_for_page_load('initial')
        
        # Get domain assessment page
        domain_assessment_page = DomainAssessmentPage(self.driver)
        domain_assessment_page.wait_for_page_load()
        RandomizedWait.wait_for_page_load('initial')
        
        # Dismiss modals
        if domain_assessment_page.is_instructions_modal_present():
            domain_assessment_page.dismiss_instructions_modal()
            RandomizedWait.wait_for_page_load('modal')
        
        domain_assessment_page.dismiss_guidance()
        
        # Answer questions
        question_helper = QuestionAnswerHelper(self.driver)
        wait = WaitHelpers(self.driver)
        
        max_questions = 100
        questions_answered = 0
        consecutive_failures = 0
        max_consecutive_failures = 3
        
        while questions_answered < max_questions:
            try:
                question_id = question_helper.get_question_id()
                if not question_id:
                    consecutive_failures += 1
                    if consecutive_failures >= max_consecutive_failures:
                        break
                    try:
                        next_button = domain_assessment_page.find_element(domain_assessment_page.NEXT_BUTTON)
                        if next_button.is_enabled():
                            next_button.click()
                            RandomizedWait.wait_for_navigation('next')
                    except:
                        pass
                    continue
                
                consecutive_failures = 0
                
                question_type = question_helper.get_question_type(question_id)
                if not question_type:
                    try:
                        question_element = self.driver.find_element(
                            'css selector',
                            f"[data-testid='domain_question__{question_id}']"
                        )
                        self.driver.execute_script("arguments[0].scrollIntoView(true);", question_element)
                        time.sleep(1)
                        question_type = question_helper.get_question_type(question_id)
                    except:
                        pass
                
                if not question_type:
                    try:
                        next_button = domain_assessment_page.find_element(domain_assessment_page.NEXT_BUTTON)
                        if next_button.is_enabled():
                            next_button.click()
                            RandomizedWait.wait_for_navigation('next')
                    except:
                        pass
                    continue
                
                try:
                    question_helper.answer_question(question_id=question_id, question_type=question_type)
                    RandomizedWait.wait_for_question_answer(question_type)
                    questions_answered += 1
                except Exception as e:
                    print(f"   ⚠️  Error answering question {question_id}: {e}")
                
                # Check submit button
                try:
                    submit_button = domain_assessment_page.find_element(domain_assessment_page.SUBMIT_BUTTON)
                    if submit_button.is_enabled():
                        submit_button.click()
                        RandomizedWait.wait_for_submission('submit')
                        break
                except:
                    pass
                
                # Click next
                try:
                    next_button = domain_assessment_page.find_element(domain_assessment_page.NEXT_BUTTON)
                    if next_button.is_enabled():
                        next_button.click()
                        RandomizedWait.wait_for_navigation('next')
                except:
                    pass
                
            except Exception as e:
                consecutive_failures += 1
                if consecutive_failures >= max_consecutive_failures:
                    break
        
        # Handle submit modal
        try:
            if domain_assessment_page.is_submit_modal_present():
                domain_assessment_page.confirm_submit()
                RandomizedWait.wait_for_submission('confirm')
        except:
            pass
        
        # Handle feedback
        try:
            feedback_page = DomainFeedbackPage(self.driver)
            if feedback_page.is_modal_present():
                feedback_page.submit_feedback(
                    question1_answer='yes',
                    question1_justification='Automated test response',
                    question2_answer='This is an automated test response for load testing purposes.'
                )
                RandomizedWait.wait_for_submission('feedback')
        except Exception as e:
            print(f"   ⚠️  Error handling feedback: {e}")
        
        self.result['steps_completed'].append('domain_assessment')
        self.result['questions_answered'] = questions_answered
        
        # Update global metrics
        with progress_lock:
            performance_metrics['questions_answered'].append(questions_answered)
        
        return True
    
    def run(self) -> Dict:
        """Run complete end-to-end flow for this student"""
        start_time = time.time()
        
        try:
            if not self.setup_driver():
                self.result['status'] = 'failed'
                return self.result
            
            if not self.step_login():
                self.result['status'] = 'failed'
                return self.result
            
            if not self.step_password_reset():
                self.result['status'] = 'failed'
                return self.result
            
            if not self.step_profile_completion():
                self.result['status'] = 'failed'
                return self.result
            
            if not self.step_complete_domain_assessment():
                self.result['status'] = 'failed'
                return self.result
            
            self.result['status'] = 'success'
            
        except Exception as e:
            self.result['status'] = 'failed'
            self.result['error'] = f"Unexpected error: {str(e)}"
        
        finally:
            if self.driver:
                try:
                    self.driver.quit()
                except:
                    pass
            
            self.result['duration'] = time.time() - start_time
            
            # Update global metrics
            with progress_lock:
                performance_metrics['total_durations'].append(self.result['duration'])
        
        return self.result


def load_students_from_csv(csv_path: str) -> List[Dict]:
    """Load students from CSV file"""
    students = []
    try:
        with open(csv_path, 'r', encoding='utf-8') as f:
            reader = csv.DictReader(f)
            for row in reader:
                cpid = (
                    row.get('Student CPID') or
                    row.get('student_cpid') or
                    row.get('Student_CPID') or
                    row.get('cpid') or
                    row.get('CPID') or
                    None
                )
                
                if not cpid:
                    continue
                
                password = (
                    row.get('Password') or
                    row.get('password') or
                    row.get('PASSWORD') or
                    None
                )
                
                students.append({
                    'cpid': cpid.strip(),
                    'data': {
                        **row,
                        'password': password.strip() if password else None
                    }
                })
    except Exception as e:
        print(f"❌ Error loading CSV: {e}")
        import traceback
        traceback.print_exc()
        return []
    
    return students


def run_student_flow(student_info: Dict, headless: bool = True, save_interval: int = 5) -> Dict:
    """Run flow for a single student"""
    cpid = student_info['cpid']
    student_data = student_info['data']
    
    student_name = f"{student_data.get('First Name', '')} {student_data.get('Last Name', '')}".strip()
    if not student_name:
        student_name = cpid
    
    print(f"🚀 Starting: {cpid} ({student_name})")
    
    student_flow = LoadTestStudent(cpid, student_data, headless=headless)
    result = student_flow.run()
    
    # Update global results
    with results_lock:
        results['total'] += 1
        results['last_update'] = datetime.now().isoformat()
        
        if result['status'] == 'success':
            results['success'] += 1
            completed_students.add(cpid)
        elif result['status'] == 'failed':
            results['failed'] += 1
            results['errors'].append({
                'cpid': cpid,
                'error': result.get('error', 'Unknown error')
            })
        else:
            results['skipped'] += 1
            completed_students.add(cpid)  # Also track skipped as completed
        
        # Save progress periodically
        if results['total'] % save_interval == 0:
            ProgressTracker.save_progress()
            ProgressTracker.print_real_time_metrics()
    
    status_emoji = '✅' if result['status'] == 'success' else '❌'
    print(f"{status_emoji} Completed: {cpid} ({student_name}) - {result['status']} - {result['duration']:.2f}s")
    
    return result


def main():
    parser = argparse.ArgumentParser(description='Advanced Load Testing Script - End-to-End Assessment Flow')
    parser.add_argument('--students', type=int, required=True, help='Number of students to test')
    parser.add_argument('--csv', type=str, required=True, help='Path to CSV file with student data')
    parser.add_argument('--concurrent', type=int, default=5, help='Number of concurrent students (default: 5)')
    parser.add_argument('--headless', action='store_true', default=True, help='Run in headless mode (default: True)')
    parser.add_argument('--no-headless', dest='headless', action='store_false', help='Run in visible mode')
    parser.add_argument('--max-visible', type=int, default=2, help='Max visible browsers when not headless (default: 2)')
    parser.add_argument('--save-interval', type=int, default=5, help='Save progress every N students (default: 5)')
    parser.add_argument('--resume', action='store_true', help='Resume from previous progress')
    parser.add_argument('--metrics-interval', type=int, default=10, help='Print metrics every N students (default: 10)')
    
    args = parser.parse_args()
    
    print("=" * 80)
    print("ADVANCED LOAD TESTING - END-TO-END ASSESSMENT FLOW")
    print("=" * 80)
    print(f"📊 Configuration:")
    print(f"   Total Students: {args.students}")
    print(f"   Concurrent: {args.concurrent}")
    print(f"   Headless: {args.headless}")
    if not args.headless:
        print(f"   Max Visible Browsers: {args.max_visible}")
    print(f"   Save Interval: Every {args.save_interval} students")
    print(f"   Metrics Interval: Every {args.metrics_interval} students")
    print(f"   Resume: {args.resume}")
    print(f"   CSV File: {args.csv}")
    print("=" * 80)
    
    # Load students
    all_students = load_students_from_csv(args.csv)
    if not all_students:
        print("❌ No students loaded from CSV")
        return
    
    # Handle resume
    if args.resume:
        progress = ProgressTracker.load_progress()
        if progress:
            print(f"📂 Resuming from previous progress...")
            completed = set(progress.get('completed_students', []))
            completed_students.update(completed)
            all_students = [s for s in all_students if s['cpid'] not in completed]
            print(f"   Skipping {len(completed)} already completed students")
            # Restore results from progress
            if 'results' in progress:
                results.update(progress['results'])
                results['start_time'] = time.time()  # Reset start time
    
    # Limit to requested number
    students_to_test = all_students[:args.students]
    print(f"\n📋 Loaded {len(students_to_test)} students from CSV")
    
    # Load student data manager
    try:
        student_data_manager.load_students_from_csv(args.csv)
    except:
        pass
    
    # Initialize results
    results['start_time'] = time.time()
    
    # Smart browser management for visible mode
    if not args.headless:
        # Limit concurrent visible browsers
        actual_concurrent = min(args.concurrent, args.max_visible)
        print(f"⚠️  Visible mode: Limiting concurrent browsers to {actual_concurrent} (to prevent crashes)")
    else:
        actual_concurrent = args.concurrent
        # Warning for high concurrency in headless mode
        if actual_concurrent > 50:
            print(f"⚠️  WARNING: Running {actual_concurrent} concurrent browsers in headless mode")
            print(f"   This may cause system stress. Monitor system resources.")
            print(f"   If crashes occur, reduce --concurrent to 20-50")
    
    print(f"\n🚀 Starting load test with {actual_concurrent} concurrent students...")
    print("=" * 80)
    
    # Run load test
    with ThreadPoolExecutor(max_workers=actual_concurrent) as executor:
        futures = {
            executor.submit(run_student_flow, student, args.headless, args.save_interval): student 
            for student in students_to_test
        }
        
        completed_count = 0
        for future in as_completed(futures):
            try:
                result = future.result()
                completed_count += 1
                
                # Print metrics periodically
                if completed_count % args.metrics_interval == 0:
                    ProgressTracker.print_real_time_metrics()
            except Exception as e:
                print(f"❌ Exception in thread: {e}")
    
    # Final save and summary
    ProgressTracker.save_progress()
    
    total_duration = time.time() - results['start_time']
    
    print("\n" + "=" * 80)
    print("FINAL SUMMARY")
    print("=" * 80)
    print(f"✅ Success: {results['success']}/{results['total']}")
    print(f"❌ Failed: {results['failed']}/{results['total']}")
    print(f"⏭️  Skipped: {results['skipped']}/{results['total']}")
    print(f"⏱️  Total Duration: {total_duration:.2f}s ({total_duration/60:.2f} minutes)")
    if results['total'] > 0:
        print(f"📊 Average per Student: {total_duration/results['total']:.2f}s")
        print(f"⚡ Rate: {results['total']/total_duration:.3f} students/second")
    
    ProgressTracker.print_real_time_metrics()
    
    if results['errors']:
        print(f"\n❌ Errors ({len(results['errors'])}):")
        for error in results['errors'][:10]:
            print(f"   - {error['cpid']}: {error['error'][:100]}")
        if len(results['errors']) > 10:
            print(f"   ... and {len(results['errors']) - 10} more")
    
    print(f"\n💾 Progress saved to: {PROGRESS_FILE}")
    print("=" * 80)


if __name__ == "__main__":
    main()