"""
ThutoAI - Complete School Assistant with Teacher Assignments & Analytics Dashboard
Meaning: "Thuto" = Learning/Education (Setswana — used for branding only)

✅ Teacher Assignment Posting — Assign work to class groups
✅ 📊 Analytics Dashboard — Track student engagement, assignments, groups
✅ 🌙 Dark Mode + 🖼️ Profile Pictures
✅ 🎙️ Voice Input + 📅 Assignment Tracker + 👥 Class Groups
✅ All deprecation warnings fixed (Gradio 4.0+ compatible)
✅ Fully commented
"""

import os
import gradio as gr
from datetime import datetime, timedelta
from typing import List, Dict, Optional
import time
import json
import base64
from collections import Counter

# ==================== STUDENT SERVICE ====================

class StudentService:
    """Manages student accounts, chat history, files, assignments, groups, and profile pictures."""

    def __init__(self):
        self.students = {
            "student1": {"password": "pass123", "name": "John Doe", "avatar": None},
            "student2": {"password": "pass456", "name": "Jane Smith", "avatar": None},
            "student3": {"password": "pass789", "name": "Alex Johnson", "avatar": None}
        }
        self.student_sessions = {
            "student1": {
                "chat_history": [],
                "files": [],
                "assignments": [
                    {"id": 1, "title": "Math Quiz", "due_date": "2025-04-25", "course": "MATH10A", "status": "pending", "assigned_by": "Mr. Smith"},
                    {"id": 2, "title": "Science Lab Report", "due_date": "2025-04-30", "course": "SCI11B", "status": "pending", "assigned_by": "Dr. Lee"}
                ],
                "groups": ["MATH10A", "SCI11B"],
                "dark_mode": False
            },
            "student2": {
                "chat_history": [],
                "files": [],
                "assignments": [
                    {"id": 3, "title": "History Essay", "due_date": "2025-04-22", "course": "HIST9A", "status": "overdue", "assigned_by": "Ms. Brown"},
                    {"id": 4, "title": "English Reading", "due_date": "2025-04-28", "course": "ENG10A", "status": "pending", "assigned_by": "Mr. White"}
                ],
                "groups": ["HIST9A", "ENG10A"],
                "dark_mode": True
            },
            "student3": {
                "chat_history": [],
                "files": [],
                "assignments": [],
                "groups": ["MATH10A", "ENG10A"],
                "dark_mode": False
            }
        }
        self.valid_groups = ["MATH10A", "MATH10B", "SCI11A", "SCI11B", "ENG10A", "ENG10B", "HIST9A", "HIST9B"]
        self.all_assignments = []  # Master list for analytics

    def register_student(self, username: str, password: str, name: str) -> str:
        if not username or not password or not name:
            return "⚠️ All fields required."
        if username in self.students:
            return "⚠️ Username already exists."
        self.students[username] = {"password": password, "name": name, "avatar": None}
        self.student_sessions[username] = {
            "chat_history": [],
            "files": [],
            "assignments": [],
            "groups": [],
            "dark_mode": False
        }
        return "✅ Account created! Please log in."

    def authenticate_student(self, username: str, password: str) -> Optional[Dict]:
        student = self.students.get(username)
        if student and student["password"] == password:
            if username not in self.student_sessions:
                self.student_sessions[username] = {
                    "chat_history": [],
                    "files": [],
                    "assignments": [],
                    "groups": [],
                    "dark_mode": False
                }
            return {
                "name": student["name"],
                "avatar": student["avatar"],
                "dark_mode": self.student_sessions[username]["dark_mode"]
            }
        return None

    def update_dark_mode(self, username: str, is_dark: bool):
        if username in self.student_sessions:
            self.student_sessions[username]["dark_mode"] = is_dark

    def update_avatar(self, username: str, avatar_path: str):
        if username in self.students and avatar_path:
            self.students[username]["avatar"] = avatar_path

    def get_chat_history(self, username: str) -> List:
        return self.student_sessions.get(username, {}).get("chat_history", [])

    def add_to_chat_history(self, username: str, user_msg: str, bot_reply: str):
        if username in self.student_sessions:
            self.student_sessions[username]["chat_history"].append((user_msg, bot_reply))

    def get_files(self, username: str) -> List:
        return self.student_sessions.get(username, {}).get("files", [])

    def add_file(self, username: str, filename: str):
        if username in self.student_sessions:
            self.student_sessions[username]["files"].append({
                "name": filename,
                "uploaded_at": datetime.now().strftime("%Y-%m-%d %H:%M")
            })

    def get_assignments(self, username: str) -> List:
        """Get assignments for groups student has joined."""
        if username not in self.student_sessions:
            return []
        student_groups = set(self.student_sessions[username]["groups"])
        all_assignments = []
        for user_data in self.student_sessions.values():
            for assignment in user_data.get("assignments", []):
                if assignment["course"] in student_groups:
                    all_assignments.append(assignment)
        # Remove duplicates by ID
        seen = set()
        unique_assignments = []
        for assignment in all_assignments:
            if assignment["id"] not in seen:
                seen.add(assignment["id"])
                unique_assignments.append(assignment)
        return sorted(unique_assignments, key=lambda x: x["due_date"])

    def get_groups(self, username: str) -> List:
        return self.student_sessions.get(username, {}).get("groups", [])

    def join_group(self, username: str, group_code: str) -> str:
        if group_code.upper() not in self.valid_groups:
            return "❌ Invalid group code. Ask your teacher for the correct code."
        if username in self.student_sessions:
            if group_code.upper() not in self.student_sessions[username]["groups"]:
                self.student_sessions[username]["groups"].append(group_code.upper())
            return f"✅ Joined group: {group_code.upper()}"
        return "❌ Login required."

    def leave_group(self, username: str, group_code: str) -> str:
        if username in self.student_sessions:
            if group_code.upper() in self.student_sessions[username]["groups"]:
                self.student_sessions[username]["groups"].remove(group_code.upper())
                return f"✅ Left group: {group_code.upper()}"
        return "❌ Group not found or not joined."

    # Analytics methods
    def get_total_students(self) -> int:
        return len(self.students)

    def get_active_students(self) -> int:
        return len([s for s in self.student_sessions.keys() if len(self.student_sessions[s]["assignments"]) > 0])

    def get_total_assignments(self) -> int:
        total = 0
        for user_data in self.student_sessions.values():
            total += len(user_data.get("assignments", []))
        return total

    def get_completed_assignments(self) -> int:
        completed = 0
        for user_data in self.student_sessions.values():
            for assignment in user_data.get("assignments", []):
                if assignment["status"] == "completed":
                    completed += 1
        return completed

    def get_group_popularity(self) -> Dict:
        all_groups = []
        for user_data in self.student_sessions.values():
            all_groups.extend(user_data.get("groups", []))
        return dict(Counter(all_groups))

    def get_recent_activity(self) -> List:
        activity = []
        for username, data in self.student_sessions.items():
            if data["assignments"]:
                latest = max(data["assignments"], key=lambda x: x.get("assigned_date", "2025-01-01"))
                activity.append({
                    "student": self.students[username]["name"],
                    "last_assignment": latest["title"],
                    "date": latest.get("assigned_date", "Unknown")
                })
        return sorted(activity, key=lambda x: x["date"], reverse=True)[:5]


# Initialize student service
student_service = StudentService()

# ==================== SCHOOL SERVICE ====================

class SchoolService:
    """Handles announcements, AI context, and shared assignments."""

    def __init__(self):
        self.announcements = [
            {
                "id": 1,
                "title": "Math Final Exam",
                "content": "Covers chapters 1-5. Bring calculator and ruler.",
                "course": "Mathematics",
                "date": "2025-04-15",
                "priority": "high",
                "posted_by": "Mr. Smith",
                "views": 45
            },
            {
                "id": 2,
                "title": "Science Project Due",
                "content": "Submit your ecology report by Friday. Include bibliography.",
                "course": "Science",
                "date": "2025-04-12",
                "priority": "normal",
                "posted_by": "Dr. Lee",
                "views": 32
            },
            {
                "id": 3,
                "title": "Library Extended Hours",
                "content": "Open until 9 PM during exam week. Quiet study zones available.",
                "course": "General",
                "date": "2025-04-10",
                "priority": "low",
                "posted_by": "Librarian",
                "views": 67
            },
        ]
        self.courses = ["All", "Mathematics", "Science", "English", "History", "General"]
        self.total_announcements = len(self.announcements)
        self.total_files = 0
        self.assignment_id_counter = 5  # Start after existing assignments

    def get_announcements(self, course_filter: str = "All") -> List[Dict]:
        if course_filter == "All":
            return self.announcements
        return [a for a in self.announcements if a["course"] == course_filter]

    def add_announcement(self, title: str, content: str, course: str, priority: str, posted_by: str = "Admin"):
        new_id = max([a["id"] for a in self.announcements], default=0) + 1
        self.announcements.append({
            "id": new_id,
            "title": title,
            "content": content,
            "course": course,
            "date": datetime.now().strftime("%Y-%m-%d"),
            "priority": priority,
            "posted_by": posted_by,
            "views": 0
        })
        self.total_announcements += 1

    def get_school_context_for_ai(self) -> str:
        context = "Current School Announcements:\n"
        for ann in self.announcements[-5:]:
            context += f"- [{ann['course']}] {ann['title']}: {ann['content'][:80]}... (Priority: {ann['priority']})\n"
        return context

    def get_stats(self) -> Dict:
        return {
            "total_announcements": self.total_announcements,
            "total_files": self.total_files,
            "active_courses": len(set(a["course"] for a in self.announcements if a["course"] != "General")),
            "high_priority": len([a for a in self.announcements if a["priority"] == "high"]),
            "total_views": sum(a["views"] for a in self.announcements)
        }

    def create_assignment(self, title: str, description: str, due_date: str, course: str, assigned_by: str) -> int:
        """Create assignment for a specific class group."""
        assignment_id = self.assignment_id_counter
        self.assignment_id_counter += 1
        
        new_assignment = {
            "id": assignment_id,
            "title": title,
            "description": description,
            "due_date": due_date,
            "course": course,
            "assigned_by": assigned_by,
            "assigned_date": datetime.now().strftime("%Y-%m-%d"),
            "status": "pending"
        }
        
        # Assign to all students in this group
        for username, data in student_service.student_sessions.items():
            if course in data["groups"]:
                data["assignments"].append(new_assignment.copy())
        
        return assignment_id


school_service = SchoolService()

# ==================== ADMIN SERVICE ====================

class AdminService:
    """Handles teacher and admin authentication."""

    def __init__(self):
        self.teachers = {
            "teacher@thutoai.edu": {"password": "password123", "name": "Mr. Smith", "role": "teacher"},
            "scienceteacher@school.org": {"password": "science123", "name": "Dr. Lee", "role": "teacher"},
            "admin@school.org": {"password": "letmein", "name": "Admin", "role": "admin"}
        }

    def authenticate(self, username: str, password: str) -> Optional[Dict]:
        user = self.teachers.get(username)
        if user and user["password"] == password:
            return {"name": user["name"], "role": user["role"]}
        return None


admin_service = AdminService()

# ==================== OPENAI SETUP ====================

OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
USE_OPENAI = bool(OPENAI_API_KEY)

if USE_OPENAI:
    try:
        from openai import OpenAI
        client = OpenAI(api_key=OPENAI_API_KEY)
    except Exception as e:
        print(f"⚠️ OpenAI error: {e}")
        USE_OPENAI = False
else:
    print("⚠️ OPENAI_API_KEY not set. Using mock responses.")

# ==================== AI CHAT FUNCTION ====================

def ai_chat(message: str, history: List, username: str = "guest") -> tuple:
    """Generate AI response with loading state and save to history."""
    if not message.strip():
        return history, ""

    thinking_msg = "🤔 ThutoAI is thinking..."
    history.append((message, thinking_msg))
    yield history, ""

    if USE_OPENAI:
        try:
            system_prompt = f"""You are ThutoAI, a friendly and knowledgeable AI assistant for students.
Context from school:
{school_service.get_school_context_for_ai()}

Guidelines:
- Be encouraging, clear, and concise.
- Use emojis sparingly to keep it fun 😊📚🎯
- If asked about deadlines or exams, refer to context.
- Offer study tips if appropriate.
- Never invent facts — say 'I don't know' if unsure."""

            response = client.chat.completions.create(
                model="gpt-3.5-turbo",
                messages=[
                    {"role": "system", "content": system_prompt},
                    {"role": "user", "content": message}
                ],
                temperature=0.7,
                max_tokens=500
            )

            reply = response.choices[0].message.content.strip()

            keywords = ["exam", "test", "due", "assignment", "deadline", "when", "what", "grade", "score"]
            if any(kw in message.lower() for kw in keywords):
                matches = school_service.get_announcements()
                relevant = [a for a in matches if any(kw in a["title"].lower() or kw in a["content"].lower() for kw in keywords)]
                if relevant:
                    reply += "\n\n📌 **Quick Info from School:**"
                    for ann in relevant[:2]:
                        emoji = "🚨" if ann["priority"] == "high" else "📌" if ann["priority"] == "normal" else "ℹ️"
                        reply += f"\n{emoji} **{ann['title']}** ({ann['course']})\n   → {ann['content'][:70]}..."

        except Exception as e:
            reply = f"⚠️ Sorry, I had a glitch: {str(e)}"
    else:
        time.sleep(1.5)
        reply = f"👋 Hi! I'm ThutoAI. You asked: '{message}'.\n💡 *Pro tip: Add your OpenAI API key in HF Secrets for smarter answers!*"

    history[-1] = (message, reply)

    if username != "guest":
        student_service.add_to_chat_history(username, message, reply)

    yield history, ""


# ==================== UI RENDERING HELPERS ====================

def render_announcements(course: str) -> str:
    """Render announcements with modern cards."""
    announcements = school_service.get_announcements(course)
    if not announcements:
        return """
        <div style='text-align: center; padding: 40px; color: #6c757d;'>
            <div style='font-size: 4em; margin-bottom: 16px;'>📭</div>
            <h3>No announcements for this course.</h3>
            <p>Check back later or select "All" to see everything.</p>
        </div>
        """

    html = "<div style='display: grid; gap: 16px;'>"
    priority_icons = {"high": "🚨", "normal": "📌", "low": "ℹ️"}
    priority_colors = {"high": "#dc3545", "normal": "#ffc107", "low": "#6c757d"}

    for ann in announcements:
        icon = priority_icons.get(ann["priority"], "📌")
        color = priority_colors.get(ann["priority"], "#6c757d")
        html += f"""
        <div style='
            background: white;
            border-radius: 12px;
            padding: 20px;
            box-shadow: 0 2px 8px rgba(0,0,0,0.08);
            border-left: 4px solid {color};
            transition: transform 0.2s, box-shadow 0.2s;
        '>
            <div style='display: flex; align-items: flex-start; gap: 12px;'>
                <div style='font-size: 1.5em;'>{icon}</div>
                <div style='flex: 1;'>
                    <div style='display: flex; justify-content: space-between; align-items: center; margin-bottom: 8px;'>
                        <h3 style='margin: 0; color: #212529;'>{ann['title']}</h3>
                        <span style='
                            background: {color};
                            color: white;
                            padding: 4px 10px;
                            border-radius: 20px;
                            font-size: 0.8em;
                            font-weight: bold;
                        '>{ann['priority'].upper()}</span>
                    </div>
                    <p style='margin: 8px 0; color: #495057; line-height: 1.5;'>{ann['content']}</p>
                    <div style='display: flex; justify-content: space-between; font-size: 0.85em; color: #6c757d; margin-top: 12px;'>
                        <span>📚 {ann['course']}</span>
                        <span>📅 {ann['date']}</span>
                        <span>👨‍🏫 {ann['posted_by']}</span>
                        <span>👁️ {ann['views']} views</span>
                    </div>
                </div>
            </div>
        </div>
        """
    html += "</div>"
    return html


def render_assignments(assignments: List[Dict]) -> str:
    """Render assignments in a clean, prioritized list."""
    if not assignments:
        return """
        <div style='text-align: center; padding: 40px; color: #6c757d;'>
            <div style='font-size: 4em; margin-bottom: 16px;'>📅</div>
            <h3>No upcoming assignments.</h3>
            <p>Ask your teacher or join a class group to see assignments.</p>
        </div>
        """

    html = "<div style='display: grid; gap: 16px;'>"
    today = datetime.today().date()

    for task in assignments:
        due_date = datetime.strptime(task["due_date"], "%Y-%m-%d").date()
        days_left = (due_date - today).days
        is_overdue = days_left < 0
        is_today = days_left == 0

        if is_overdue:
            badge = "🚨 OVERDUE"
            color = "#dc3545"
        elif is_today:
            badge = "🎯 TODAY"
            color = "#fd7e14"
        elif days_left <= 2:
            badge = f"⚠️ Due in {days_left} day{'s' if days_left != 1 else ''}"
            color = "#ffc107"
        else:
            badge = f"✅ Due in {days_left} days"
            color = "#28a745"

        html += f"""
        <div style='
            background: white;
            border-radius: 12px;
            padding: 20px;
            box-shadow: 0 2px 8px rgba(0,0,0,0.08);
            border-left: 4px solid {color};
            transition: transform 0.2s;
        '>
            <div style='display: flex; justify-content: space-between; align-items: flex-start;'>
                <div>
                    <h3 style='margin: 0 0 8px 0; color: #212529;'>{task['title']}</h3>
                    <div style='color: #6c757d; margin-bottom: 8px;'>📚 {task['course']} · 👩‍🏫 {task['assigned_by']}</div>
                    <div style='color: #495057;'>📅 Due: {task['due_date']}</div>
                    <div style='color: #6c757d; font-size: 0.9em;'>{task.get('description', '')}</div>
                </div>
                <span style='
                    background: {color};
                    color: white;
                    padding: 6px 12px;
                    border-radius: 20px;
                    font-weight: bold;
                    font-size: 0.85em;
                    align-self: flex-start;
                '>{badge}</span>
            </div>
        </div>
        """

    html += "</div>"
    return html


def render_groups(groups: List[str]) -> str:
    """Render joined class groups."""
    if not groups:
        return """
        <div style='text-align: center; padding: 40px; color: #6c757d;'>
            <div style='font-size: 4em; margin-bottom: 16px;'>👥</div>
            <h3>You haven't joined any class groups yet.</h3>
            <p>Ask your teacher for a group code to join your class.</p>
        </div>
        """

    html = "<div style='display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 16px;'>"
    for group in groups:
        html += f"""
        <div style='
            background: #e3f2fd;
            border-radius: 12px;
            padding: 20px;
            text-align: center;
            box-shadow: 0 2px 4px rgba(0,0,0,0.05);
            border: 2px solid #2196f3;
        '>
            <div style='font-size: 1.5em; margin-bottom: 8px;'>🎒</div>
            <h3 style='margin: 0; color: #1976d2;'>{group}</h3>
            <p style='margin: 8px 0 0 0; color: #555; font-size: 0.9em;'>Class Group</p>
        </div>
        """
    html += "</div>"
    return html


def get_avatar_html(avatar_path: Optional[str], name: str) -> str:
    """Generate HTML for avatar display."""
    if avatar_path:
        try:
            with open(avatar_path, "rb") as f:
                img_data = base64.b64encode(f.read()).decode()
            img_html = f'<img src="data:image/png;base64,{img_data}" style="width: 60px; height: 60px; border-radius: 50%; object-fit: cover; border: 2px solid #6e8efb;">'
        except:
            img_html = f'<div style="width: 60px; height: 60px; border-radius: 50%; background: #6e8efb; color: white; display: flex; align-items: center; justify-content: center; font-weight: bold; font-size: 1.2em; border: 2px solid #6e8efb;">{name[0].upper()}</div>'
    else:
        img_html = f'<div style="width: 60px; height: 60px; border-radius: 50%; background: #6e8efb; color: white; display: flex; align-items: center; justify-content: center; font-weight: bold; font-size: 1.2em; border: 2px solid #6e8efb;">{name[0].upper()}</div>'

    return img_html


def render_analytics() -> str:
    """Render analytics dashboard for admins."""
    total_students = student_service.get_total_students()
    active_students = student_service.get_active_students()
    total_assignments = student_service.get_total_assignments()
    completed_assignments = student_service.get_completed_assignments()
    group_popularity = student_service.get_group_popularity()
    recent_activity = student_service.get_recent_activity()
    school_stats = school_service.get_stats()

    completion_rate = (completed_assignments / total_assignments * 100) if total_assignments > 0 else 0

    html = f"""
    <div style='display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; margin-bottom: 32px;'>
        <div style='background: white; padding: 20px; border-radius: 12px; box-shadow: 0 2px 8px rgba(0,0,0,0.08);'>
            <h3 style='color: #212529; margin: 0 0 16px 0;'>👥 Student Engagement</h3>
            <div style='display: grid; grid-template-columns: 1fr 1fr; gap: 16px;'>
                <div style='text-align: center; padding: 16px; background: #e3f2fd; border-radius: 8px;'>
                    <div style='font-size: 2em; color: #1976d2;'>{total_students}</div>
                    <div>Total Students</div>
                </div>
                <div style='text-align: center; padding: 16px; background: #e8f5e8; border-radius: 8px;'>
                    <div style='font-size: 2em; color: #2e7d32;'>{active_students}</div>
                    <div>Active Students</div>
                </div>
            </div>
        </div>
        
        <div style='background: white; padding: 20px; border-radius: 12px; box-shadow: 0 2px 8px rgba(0,0,0,0.08);'>
            <h3 style='color: #212529; margin: 0 0 16px 0;'>📊 Assignment Stats</h3>
            <div style='display: grid; grid-template-columns: 1fr 1fr; gap: 16px;'>
                <div style='text-align: center; padding: 16px; background: #fff3e0; border-radius: 8px;'>
                    <div style='font-size: 2em; color: #ef6c00;'>{total_assignments}</div>
                    <div>Total Assignments</div>
                </div>
                <div style='text-align: center; padding: 16px; background: #f3e5f5; border-radius: 8px;'>
                    <div style='font-size: 2em; color: #7b1fa2;'>{completion_rate:.1f}%</div>
                    <div>Completion Rate</div>
                </div>
            </div>
        </div>
    </div>

    <div style='display: grid; grid-template-columns: 1fr 1fr; gap: 24px; margin-bottom: 32px;'>
        <div style='background: white; padding: 20px; border-radius: 12px; box-shadow: 0 2px 8px rgba(0,0,0,0.08);'>
            <h3 style='color: #212529; margin: 0 0 16px 0;'>📈 Popular Class Groups</h3>
            <div style='display: grid; gap: 12px;'>
    """

    sorted_groups = sorted(group_popularity.items(), key=lambda x: x[1], reverse=True)
    for group, count in sorted_groups[:5]:
        percentage = (count / total_students * 100) if total_students > 0 else 0
        html += f"""
                <div style='display: flex; align-items: center; gap: 12px;'>
                    <div style='width: 100%; background: #e0e0e0; height: 8px; border-radius: 4px;'>
                        <div style='width: {percentage}%; background: #6e8efb; height: 100%; border-radius: 4px;'></div>
                    </div>
                    <div style='min-width: 80px;'>{group}</div>
                    <div style='color: #6c757d;'>{count} students</div>
                </div>
        """

    html += """
            </div>
        </div>

        <div style='background: white; padding: 20px; border-radius: 12px; box-shadow: 0 2px 8px rgba(0,0,0,0.08);'>
            <h3 style='color: #212529; margin: 0 0 16px 0;'>📢 Announcement Stats</h3>
            <div style='display: grid; gap: 12px;'>
    """

    for ann in school_service.announcements[:5]:
        views = ann.get("views", 0)
        max_views = max(a.get("views", 0) for a in school_service.announcements) if school_service.announcements else 1
        width_percent = (views / max_views * 100) if max_views > 0 else 0
        html += f"""
                <div style='display: flex; align-items: center; gap: 12px;'>
                    <div style='width: 100%; background: #e0e0e0; height: 8px; border-radius: 4px;'>
                        <div style='width: {width_percent}%; background: #ff7043; height: 100%; border-radius: 4px;'></div>
                    </div>
                    <div style='min-width: 120px; font-size: 0.9em;'>{ann['title'][:20]}...</div>
                    <div style='color: #6c757d;'>{views} views</div>
                </div>
        """

    html += """
            </div>
        </div>
    </div>

    <div style='background: white; padding: 20px; border-radius: 12px; box-shadow: 0 2px 8px rgba(0,0,0,0.08);'>
        <h3 style='color: #212529; margin: 0 0 16px 0;'>⏱️ Recent Activity</h3>
        <div style='display: grid; gap: 12px;'>
    """

    for activity in recent_activity:
        html += f"""
            <div style='padding: 12px; background: #f8f9fa; border-radius: 8px; display: flex; justify-content: space-between; align-items: center;'>
                <div>
                    <strong>{activity['student']}</strong> received assignment: <em>{activity['last_assignment']}</em>
                </div>
                <div style='color: #6c757d; font-size: 0.9em;'>{activity['date']}</div>
            </div>
        """

    html += """
        </div>
    </div>
    """

    return html

# ==================== STATE MANAGEMENT ====================

CURRENT_USER = "guest"
CURRENT_TEACHER = None
DARK_MODE = False

def login_student(username: str, password: str) -> tuple:
    global CURRENT_USER, DARK_MODE
    student_data = student_service.authenticate_student(username, password)
    if student_data:
        CURRENT_USER = username
        DARK_MODE = student_data["dark_mode"]
        chat_history = student_service.get_chat_history(username)
        files = student_service.get_files(username)
        assignments = student_service.get_assignments(username)
        groups = student_service.get_groups(username)
        avatar_html = get_avatar_html(student_data["avatar"], student_data["name"])
        welcome_msg = f"Welcome back, {student_data['name']}!"

        css_class = "dark-mode" if DARK_MODE else ""

        return (
            gr.update(visible=False),
            gr.update(visible=True),
            chat_history,
            files,
            render_assignments(assignments),
            render_groups(groups),
            welcome_msg,
            gr.update(value=student_data["name"], visible=True),
            gr.update(visible=True),
            gr.update(value=avatar_html),
            gr.update(value="🌙 Light Mode" if DARK_MODE else "☀️ Dark Mode"),
            css_class
        )
    return (
        gr.update(visible=True),
        gr.update(visible=False),
        [],
        [],
        "",
        "",
        "❌ Invalid username or password",
        gr.update(visible=False),
        gr.update(visible=False),
        gr.update(),
        gr.update(),
        ""
    )

def register_student(username: str, password: str, name: str) -> str:
    return student_service.register_student(username, password, name)

def logout_student() -> tuple:
    global CURRENT_USER, DARK_MODE
    CURRENT_USER = "guest"
    DARK_MODE = False
    return (
        gr.update(visible=True),
        gr.update(visible=False),
        [],
        [],
        "",
        "",
        "",
        gr.update(visible=False),
        gr.update(visible=False),
        gr.update(),
        gr.update(value="☀️ Dark Mode"),
        ""
    )

def toggle_dark_mode() -> tuple:
    global DARK_MODE, CURRENT_USER
    DARK_MODE = not DARK_MODE
    if CURRENT_USER != "guest":
        student_service.update_dark_mode(CURRENT_USER, DARK_MODE)
    btn_text = "🌙 Light Mode" if DARK_MODE else "☀️ Dark Mode"
    css_class = "dark-mode" if DARK_MODE else ""
    return btn_text, css_class

def upload_avatar(file) -> str:
    if not file:
        return "❌ No file selected"
    if CURRENT_USER == "guest":
        return "❌ Please log in first"
    student_service.update_avatar(CURRENT_USER, file.name)
    return f"✅ Avatar updated!"

def join_group(group_code: str) -> tuple:
    if CURRENT_USER == "guest":
        return "❌ Please log in first.", ""
    result = student_service.join_group(CURRENT_USER, group_code)
    groups = student_service.get_groups(CURRENT_USER)
    return result, render_groups(groups)

def leave_group(group_code: str) -> tuple:
    if CURRENT_USER == "guest":
        return "❌ Please log in first.", ""
    result = student_service.leave_group(CURRENT_USER, group_code)
    groups = student_service.get_groups(CURRENT_USER)
    return result, render_groups(groups)

def upload_file_for_student(file) -> str:
    if not file:
        return "❌ No file selected"
    result = f"✅ Uploaded: {file.name}"
    if CURRENT_USER != "guest":
        student_service.add_file(CURRENT_USER, file.name)
    return result

# ==================== TEACHER FUNCTIONS ====================

def teacher_login(username: str, password: str) -> tuple:
    global CURRENT_TEACHER
    teacher_data = admin_service.authenticate(username, password)
    if teacher_data and teacher_data["role"] == "teacher":
        CURRENT_TEACHER = teacher_data
        return (
            gr.update(visible=False),
            gr.update(visible=True),
            f"✅ Welcome, {teacher_data['name']}!",
            gr.update(visible=True)
        )
    elif teacher_data and teacher_data["role"] == "admin":
        CURRENT_TEACHER = teacher_data
        return (
            gr.update(visible=False),
            gr.update(visible=True),
            f"✅ Welcome, Admin {teacher_data['name']}!",
            gr.update(visible=True)
        )
    return (
        gr.update(visible=True),
        gr.update(visible=False),
        "❌ Invalid credentials or not a teacher account",
        gr.update(visible=False)
    )

def teacher_logout():
    global CURRENT_TEACHER
    CURRENT_TEACHER = None
    return (
        gr.update(visible=True),
        gr.update(visible=False),
        "",
        gr.update(visible=False)
    )

def create_assignment(title: str, description: str, due_date: str, course: str) -> str:
    if not CURRENT_TEACHER:
        return "🔒 Please log in as teacher first."
    if not title or not due_date or not course:
        return "⚠️ Title, due date, and course are required."
    if course not in student_service.valid_groups:
        return "⚠️ Invalid course/group. Choose from available groups."

    assignment_id = school_service.create_assignment(
        title=title,
        description=description,
        due_date=due_date,
        course=course,
        assigned_by=CURRENT_TEACHER["name"]
    )

    # Count how many students received this assignment
    recipients = 0
    for data in student_service.student_sessions.values():
        if course in data["groups"]:
            recipients += 1

    return f"✅ Assignment created! ID: {assignment_id}. Sent to {recipients} students in {course}."

# ==================== VOICE INPUT ====================

VOICE_JS = """
async function startVoiceInput() {
    if (!('webkitSpeechRecognition' in window) && !('SpeechRecognition' in window)) {
        alert('🎙️ Voice input is not supported in your browser. Try Chrome or Edge.');
        return '';
    }

    const recognition = new (window.SpeechRecognition || window.webkitSpeechRecognition)();
    recognition.lang = 'en-US';
    recognition.interimResults = false;
    recognition.maxAlternatives = 1;

    return new Promise((resolve) => {
        recognition.start();
        recognition.onresult = (event) => {
            const transcript = event.results[0][0].transcript;
            resolve(transcript);
        };
        recognition.onerror = (event) => {
            alert('🎙️ Error: ' + event.error);
            resolve('');
        };
    });
}
"""

def voice_input_handler() -> str:
    return ""

# ==================== CUSTOM CSS ====================

CUSTOM_CSS = """
.gradio-container {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    max-width: 1200px;
    margin: 0 auto;
    padding: 16px;
    transition: background-color 0.3s, color 0.3s;
}

.dark-mode {
    --background-fill-primary: #1e1e1e !important;
    --background-fill-secondary: #2d2d2d !important;
    --text-color: #f0f0f0 !important;
    --button-primary-background-fill: #5a5a5a !important;
    --button-secondary-background-fill: #3a3a3a !important;
    --input-background-fill: #2d2d2d !important;
    --input-border-color: #444 !important;
}

.primary {
    background: linear-gradient(135deg, #6e8efb, #a777e3) !important;
    border: none !important;
    color: white !important;
}

.chatbot-container {
    background: #f8f9fa !important;
    border-radius: 16px !important;
}

.dark-mode .chatbot-container {
    background: #2d2d2d !important;
}

.user, .bot {
    border-radius: 18px !important;
    padding: 12px 16px !important;
}

.file-upload {
    border: 2px dashed #6e8efb !important;
    border-radius: 12px !important;
    background: #f8f9ff !important;
}

.dark-mode .file-upload {
    background: #2a2a2a !important;
    border-color: #5a5a5a !important;
}

.analytics-card {
    background: white;
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}
"""

# ==================== BUILD UI ====================

with gr.Blocks(css=CUSTOM_CSS, theme=gr.themes.Soft(primary_hue="indigo")) as demo:
    # Header with dark mode toggle
    with gr.Row():
        gr.Markdown("# 🎓 ThutoAI — Your AI School Assistant")
        dark_mode_btn = gr.Button("☀️ Dark Mode", variant="secondary")

    # ========= STUDENT LOGIN/REGISTER =========
    with gr.Group() as login_group:
        gr.Markdown("### 🔐 Student Login")
        with gr.Row():
            login_username = gr.Textbox(label="Username", scale=3)
            login_password = gr.Textbox(label="Password", type="password", scale=3)
        login_btn = gr.Button("🔓 Login", variant="primary")
        register_btn = gr.Button("📝 Register", variant="secondary")
        login_status = gr.Textbox(label="Status", interactive=False)

        with gr.Accordion("📝 Register New Account", open=False):
            reg_username = gr.Textbox(label="Username")
            reg_password = gr.Textbox(label="Password", type="password")
            reg_name = gr.Textbox(label="Full Name")
            reg_btn = gr.Button("Create Account")
            reg_status = gr.Textbox(label="Registration Status")

    # ========= MAIN APP (hidden until login) =========
    with gr.Group(visible=False) as main_app:
        # Profile header
        with gr.Row():
            avatar_display = gr.HTML()
            user_display = gr.Textbox(label="Logged in as", interactive=False, visible=True)
            logout_btn = gr.Button("⬅️ Logout", variant="secondary")

        with gr.Tabs():
            with gr.Tab("📢 Announcements"):
                gr.Markdown("### Filter by Course or Subject")
                with gr.Row():
                    course_filter = gr.Dropdown(
                        choices=school_service.courses,
                        value="All",
                        label="Select Course",
                        scale=3
                    )
                    refresh_btn = gr.Button("🔄 Refresh", variant="secondary", scale=1)
                announcements_html = gr.HTML()
                course_filter.change(fn=render_announcements, inputs=course_filter, outputs=announcements_html)
                refresh_btn.click(fn=render_announcements, inputs=course_filter, outputs=announcements_html)
                demo.load(fn=render_announcements, inputs=course_filter, outputs=announcements_html)

            with gr.Tab("💬 Ask ThutoAI"):
                gr.Markdown("### 💡 Ask me anything — I'm here to help!")
                chatbot = gr.Chatbot(
                    height=480,
                    type='messages'  # ✅ FIXED: Replaced deprecated bubble_full_width
                )
                with gr.Row():
                    msg = gr.Textbox(
                        label="Type your question",
                        placeholder="E.g., How do I prepare for the Math exam?",
                        scale=7
                    )
                    voice_btn = gr.Button("🎙️ Speak", variant="secondary", scale=1)
                    submit_btn = gr.Button("➤ Send", variant="primary", scale=1)
                clear_btn = gr.Button("🗑️ Clear Chat", variant="secondary")

                def respond(message, chat_history):
                    for updated_history, _ in ai_chat(message, chat_history, CURRENT_USER):
                        yield updated_history, ""

                msg.submit(respond, [msg, chatbot], [msg, chatbot])
                submit_btn.click(respond, [msg, chatbot], [msg, chatbot])
                clear_btn.click(lambda: [], None, chatbot)

                voice_btn.click(
                    fn=voice_input_handler,
                    inputs=None,
                    outputs=msg,
                    js=VOICE_JS + "return startVoiceInput();"
                )

            with gr.Tab("📅 Assignments"):
                gr.Markdown("### 📌 Your Upcoming Assignments & Exams")
                assignments_display = gr.HTML()
                demo.load(
                    fn=lambda: render_assignments(student_service.get_assignments(CURRENT_USER)) if CURRENT_USER != "guest" else "",
                    inputs=None,
                    outputs=assignments_display
                )

            with gr.Tab("👥 Class Groups"):
                gr.Markdown("### 🎒 Join Your Class Groups")
                with gr.Row():
                    group_code_input = gr.Textbox(label="Group Code (e.g., MATH10A)", scale=3)
                    join_btn = gr.Button("➕ Join Group", variant="primary", scale=1)
                    leave_btn = gr.Button("➖ Leave Group", variant="secondary", scale=1)
                group_status = gr.Textbox(label="Status")
                groups_display = gr.HTML()
                join_btn.click(
                    fn=join_group,
                    inputs=group_code_input,
                    outputs=[group_status, groups_display]
                )
                leave_btn.click(
                    fn=leave_group,
                    inputs=group_code_input,
                    outputs=[group_status, groups_display]
                )
                demo.load(
                    fn=lambda: render_groups(student_service.get_groups(CURRENT_USER)) if CURRENT_USER != "guest" else "",
                    inputs=None,
                    outputs=groups_display
                )

            with gr.Tab("📂 My Files"):
                gr.Markdown("### 📁 Upload & Manage Study Materials")
                with gr.Row():
                    file_input = gr.File(label="Drag & drop or click to upload", elem_classes=["file-upload"])
                    upload_btn = gr.Button("📤 Upload", variant="primary")
                upload_status = gr.Textbox(label="Status")
                file_list = gr.JSON(label="Your Files")

                upload_btn.click(
                    fn=upload_file_for_student,
                    inputs=file_input,
                    outputs=upload_status
                )
                demo.load(
                    fn=lambda: student_service.get_files(CURRENT_USER) if CURRENT_USER != "guest" else [],
                    inputs=None,
                    outputs=file_list
                )

            with gr.Tab("🖼️ Profile"):
                gr.Markdown("### 🖼️ Update Your Profile Picture")
                with gr.Row():
                    avatar_input = gr.File(label="Choose an image (PNG, JPG)", file_types=["image"])
                    upload_avatar_btn = gr.Button("📤 Upload Avatar", variant="primary")
                avatar_status = gr.Textbox(label="Status")
                upload_avatar_btn.click(
                    fn=upload_avatar,
                    inputs=avatar_input,
                    outputs=avatar_status
                )
                demo.load(
                    fn=lambda: get_avatar_html(
                        student_service.students[CURRENT_USER]["avatar"] if CURRENT_USER != "guest" else None,
                        student_service.students[CURRENT_USER]["name"] if CURRENT_USER != "guest" else "Guest"
                    ) if CURRENT_USER != "guest" else "",
                    inputs=None,
                    outputs=avatar_display
                )

            with gr.Tab("👩‍🏫 Teacher Panel"):
                gr.Markdown("### 🔑 Teacher Login (for assignment creation)")

                with gr.Group() as teacher_login_group:
                    teacher_username = gr.Textbox(label="Teacher Username")
                    teacher_password = gr.Textbox(label="Password", type="password")
                    teacher_login_btn = gr.Button("🔓 Login", variant="primary")
                    teacher_status = gr.Textbox(label="Status")

                with gr.Group(visible=False) as teacher_dashboard:
                    gr.Markdown("### ✍️ Create New Assignment")
                    assignment_title = gr.Textbox(label="Assignment Title", placeholder="e.g., Chapter 5 Quiz")
                    assignment_description = gr.Textbox(label="Description", placeholder="Instructions for students...", lines=2)
                    assignment_due_date = gr.Textbox(label="Due Date (YYYY-MM-DD)", placeholder="2025-05-01")
                    assignment_course = gr.Dropdown(
                        choices=student_service.valid_groups,
                        label="Assign to Class Group",
                        value="MATH10A"
                    )
                    create_assignment_btn = gr.Button("📬 Create Assignment", variant="primary")
                    assignment_result = gr.Textbox(label="Result")

                    # ✅ FIXED: Removed deprecated 'inline' parameter
                    assignment_priority = gr.Radio(
                        ["low", "normal", "high"],
                        label="Priority",
                        value="normal"
                    )

                    teacher_logout_btn = gr.Button("⬅️ Logout", variant="secondary")

                teacher_login_btn.click(
                    fn=teacher_login,
                    inputs=[teacher_username, teacher_password],
                    outputs=[teacher_login_group, teacher_dashboard, teacher_status, create_assignment_btn]
                )
                teacher_logout_btn.click(
                    fn=teacher_logout,
                    inputs=None,
                    outputs=[teacher_login_group, teacher_dashboard, teacher_status, assignment_result]
                )
                create_assignment_btn.click(
                    fn=create_assignment,
                    inputs=[assignment_title, assignment_description, assignment_due_date, assignment_course],
                    outputs=assignment_result
                )

            with gr.Tab("📊 Admin Analytics"):
                gr.Markdown("### 📈 School Analytics Dashboard")
                analytics_display = gr.HTML()
                refresh_analytics_btn = gr.Button("🔄 Refresh Analytics")
                refresh_analytics_btn.click(
                    fn=render_analytics,
                    inputs=None,
                    outputs=analytics_display
                )
                demo.load(
                    fn=render_analytics,
                    inputs=None,
                    outputs=analytics_display
                )

        # Logout button (already in header)

    # ========= EVENT HANDLERS =========
    login_btn.click(
        fn=login_student,
        inputs=[login_username, login_password],
        outputs=[
            login_group, main_app, chatbot, gr.update(), assignments_display, groups_display,
            login_status, user_display, logout_btn, avatar_display, dark_mode_btn, gr.update()
        ]
    )

    register_btn.click(
        fn=register_student,
        inputs=[reg_username, reg_password, reg_name],
        outputs=reg_status
    )

    dark_mode_btn.click(
        fn=toggle_dark_mode,
        inputs=None,
        outputs=[dark_mode_btn, gr.update()]
    )

# Launch app
if __name__ == "__main__":
    demo.launch()