import email
import os
import json
import hashlib
from datetime import datetime
import firebase_admin
from firebase_admin import credentials, firestore, auth as firebase_auth

# Initialize Firebase
def initialize_firebase():
    """
    Initialize Firebase using environment variable or file fallback.
    Priority:
    1. FIREBASE_CREDENTIALS_JSON env var (HF Spaces/production)
    2. firebase-credentials.json file (local development)

    On HF Spaces: MUST have FIREBASE_CREDENTIALS_JSON set (fails loudly if missing)
    Locally: Falls back to file, then mock mode for development
    """
    # Check if running on HF Spaces
    is_hf_space = os.environ.get('SPACE_ID') is not None

    try:
        # Try environment variable first (HF Spaces/production)
        firebase_creds_json = os.environ.get('FIREBASE_CREDENTIALS_JSON')

        if firebase_creds_json:
            print("Loading Firebase credentials from FIREBASE_CREDENTIALS_JSON environment variable")
            cred_dict = json.loads(firebase_creds_json)
            cred = credentials.Certificate(cred_dict)
        elif is_hf_space:
            # Running on HF Spaces but no credentials - FAIL LOUDLY
            raise RuntimeError(
                "CRITICAL ERROR: Running on Hugging Face Spaces but FIREBASE_CREDENTIALS_JSON is not set!\n"
                "Please add the secret in Space Settings > Repository Secrets.\n"
                "The application cannot run without Firebase credentials."
            )
        else:
            # Local development - try file fallback
            print("Loading Firebase credentials from firebase-credentials.json file")
            cred = credentials.Certificate('firebase-credentials.json')

        firebase_admin.initialize_app(cred)
        db = firestore.client()
        print("✅ Firebase initialized successfully!")
        return True

    except FileNotFoundError:
        if is_hf_space:
            raise RuntimeError("CRITICAL ERROR: Firebase credentials not found on HF Spaces!")
        print("⚠️  firebase-credentials.json not found. Using mock mode for local development.")
        return False
    except json.JSONDecodeError as e:
        if is_hf_space:
            raise RuntimeError(f"CRITICAL ERROR: Invalid JSON in FIREBASE_CREDENTIALS_JSON: {e}")
        print(f"⚠️  Invalid JSON in credentials: {e}. Using mock mode.")
        return False
    except Exception as e:
        if is_hf_space:
            raise RuntimeError(f"CRITICAL ERROR: Firebase initialization failed on HF Spaces: {e}")
        print(f"⚠️  Firebase initialization failed: {e}. Using mock mode for local development.")
        return False

# Initialize Firebase
FIREBASE_ENABLED = initialize_firebase()
db = firestore.client() if FIREBASE_ENABLED else None

# Mock databases for development/testing
mock_users = {}
mock_agents = {}
mock_workspaces = {}

# Default workspace ID (same for all users)
DEFAULT_WORKSPACE_ID = "q7KfX2rP9Wb83hNa64RmTpUiAZ0vL3dS"


def hash_password(password):
    """Hash password for storage"""
    return hashlib.sha256(password.encode()).hexdigest()


def generate_workspace_data(user_id, workspace_id):
    """
    Generate workspace data with shareScript
    """
    share_script = f'''<script> (function (w, d) {{ w.CLIENT_IDENTIFIER = "{user_id}"; w.WORKSPACE_IDENTIFIER = '{workspace_id}'; w.AVATAR_IMAGE_URL = 'https://firebasestorage.googleapis.com/v0/b/curious-learner-3845a.appspot.com/o/avatars%2Fchatbot.png?alt=media&token=7d937685-197b-4947-b9f9-3c05f0271d20'; w.CHATBOT_IDENTIFIER = ''; var h = d.head || d.getElementsByTagName("head")[0]; var s = d.createElement('script'); s.setAttribute('type', 'text/javascript'); s.async = true; s.setAttribute('src', 'https://dynamic-ui-chatbot.web.app/client.js'); h.appendChild(s); }})(window, document); </script>'''

    return {
        'chatbotType': 'widget',
        'id': workspace_id,
        'shareScript': share_script,
        'workspaceName': 'Default Workspace'
    }


def register_user(username, email, password):
    """
    Register a new user in Firebase
    Returns: (success: bool, message: str, user_id: str or None)
    """
    try:
        if FIREBASE_ENABLED:
            # Create user in Firebase Auth
            user = firebase_auth.create_user(
                email=email,
                password=password,
                display_name=username
            )

            # Store user data in g_users collection
            user_data = {
                'name': username,
                'email': email,
                'created_at': firestore.SERVER_TIMESTAMP
            }
            db.collection('g_users').document(user.uid).set(user_data)

            # Create default workspace as subcollection inside user's document
            # Path: g_users/{user_id}/workspaces/{DEFAULT_WORKSPACE_ID}
            workspace_data = generate_workspace_data(user.uid, DEFAULT_WORKSPACE_ID)
            workspace_data['timestamp'] = firestore.SERVER_TIMESTAMP
            db.collection('g_users').document(user.uid).collection('workspaces').document(DEFAULT_WORKSPACE_ID).set(
                workspace_data)

            return True, "Registration successful!", user.uid
        else:
            # Mock registration
            if email in mock_users:
                return False, "User already exists!", None

            user_id = hashlib.sha256(f"{email}{datetime.now()}".encode()).hexdigest()[:28]

            workspace_data = generate_workspace_data(user_id, DEFAULT_WORKSPACE_ID)
            workspace_data['timestamp'] = datetime.now()

            mock_users[email] = {
                'user_id': user_id,
                'name': username,
                'email': email,
                'password': hash_password(password),
                'created_at': datetime.now(),
                'workspaces': {
                    DEFAULT_WORKSPACE_ID: workspace_data
                }
            }

            return True, "Registration successful!", user_id

    except Exception as e:
        return False, f"Registration failed: {str(e)}", None


def login_user(email, password):
    """
    Login user
    Returns: (success: bool, message: str, user_id: str or None)
    """
    try:
        if FIREBASE_ENABLED:
            # In production, you'd verify with Firebase Auth
            # For Gradio, we'll use a simplified approach
            users = db.collection('g_users').where('email', '==', email).limit(1).get()
            if users:
                user_doc = list(users)[0]
                user_id = user_doc.id
                return True, "Login successful!", user_id
            else:
                return False, "Invalid credentials!", None
        else:
            # Mock login
            if email in mock_users:
                user_data = mock_users[email]
                if user_data['password'] == hash_password(password):
                    return True, "Login successful!", user_data['user_id']
            return False, "Invalid credentials!", None

    except Exception as e:
        return False, f"Login failed: {str(e)}", None


def generate_chatbot_share_script(user_id, workspace_id, chatbot_id):
    """
    Generate shareScript for chatbot
    """
    return f'''<script> (function (w, d) {{ w.CLIENT_IDENTIFIER = "{user_id}"; w.WORKSPACE_IDENTIFIER = '{workspace_id}'; w.AVATAR_IMAGE_URL = 'https://firebasestorage.googleapis.com/v0/b/curious-learner-3845a.appspot.com/o/avatars%2Ffemale_profile.png?alt=media&token=58bf4a74-24c8-41b1-b8bd-e381b798bb8d'; w.CHATBOT_IDENTIFIER = '{chatbot_id}'; var h = d.head || d.getElementsByTagName("head")[0]; var s = d.createElement('script'); s.setAttribute('type', 'text/javascript'); s.async = true; s.setAttribute('src', 'https://dynamic-ui-chatbot.web.app/client.js'); h.appendChild(s); }})(window, document); </script>'''


def generate_chatbot_data(user_id, workspace_id, chatbot_id, chatbot_name, provider_name, model_name,
                          mcp_github_enabled, github_token,
                          system_prompt):
    """
    Generate chatbot document data with agent configuration
    """
    # Build MCP config for chatMessageModels
    mcp_config = {}
    if mcp_github_enabled and github_token:
        mcp_config["github"] = {
            "url": "https://api.githubcopilot.com/mcp/",
            "transport": "streamable_http",
            "headers": {
                "Authorization": f"Bearer {github_token}"
            }
        }

    # Map provider name to lowercase for consistency
    provider_lower = provider_name.lower()

    # Agent chat message model
    agent_message_model = {
        'chatMessageType': 'agent',
        'chatMessage': 'Hi I am a GitHub MCP server bot, how can I help you today?',
        'llm': {
            'provider': provider_lower,  # Use the provider from user input
            'model': model_name
        },
        'mcp': mcp_config,
        'systemPrompt': system_prompt,
        'errorText': '',
        'replayType': 'multiple',
        'validationRegex': '',
        'switchButtonModels': [
            {
                'title': 'Back Button',
                'value': True,
                'isDisabled': False
            },
            {
                'title': 'Skip Button',
                'value': True,
                'isDisabled': False
            }
        ],
        'optionModels': []
    }

    return {
        'chatMessageModels': [agent_message_model],
        'chatbotName': chatbot_name,
        'chatbotType': 'widget',
        'designModel': {
            'avatarModel': {
                'avatarType': 'asset',
                'value': 'asset/image/female_profile.png'
            },
            'branding': True,
            'dynamicTheme': '{}',
            'isDynamicTheme': False,
            'position': 'bottomRight',
            'primaryColor': 4287203839,
            'themeColor': 4294967295,
            'welcomeMessage': True
        },
        'id': chatbot_id,
        "notificationModel": {
            "sendTo": [
                "afmjoaa@gmail.com",
                "mprattoy@gmail.com"
            ],
            "subjectHeader": "New Response from Curious Learner",
            "sendIncompleteResponse": True,
            "leadInfo": "notificationCount",
            "emailNotification": True
        },
        'responseCount': 0,
        'shareScript': generate_chatbot_share_script(user_id, workspace_id, chatbot_id)
    }


def create_agent(user_id, agent_name, provider_name, model_name, mcp_github_enabled, github_token, system_prompt):
    """
    Create a new React agent
    Args:
        user_id: User ID creating the agent
        agent_name: Name of the agent
        provider_name: AI provider (OpenAI or Gemini)
        model_name: Model to use
        mcp_github_enabled: Whether GitHub MCP is enabled
        github_token: GitHub token if MCP enabled
        system_prompt: System prompt for the agent

    Returns: (success: bool, message: str, chatbot_id: str or None, share_script: str or None)
    """
    if not user_id:
        return False, "Please login first!", None, None

    if not agent_name or not provider_name or not model_name or not system_prompt:
        return False, "Agent name, provider, model, and system prompt are required!", None, None

    # Validate GitHub token if GitHub MCP is enabled
    if mcp_github_enabled and not github_token:
        return False, "GitHub token is required when GitHub MCP is enabled!", None, None

    try:
        agent_id = hashlib.sha256(f"{agent_name}{user_id}{datetime.now()}".encode()).hexdigest()[:12]

        # Generate unique chatbot ID (UUID format)
        import uuid
        chatbot_id = str(uuid.uuid1())

        # Build MCP config
        mcp_config = {}
        if mcp_github_enabled:
            mcp_config["github"] = {
                "url": "https://api.githubcopilot.com/mcp/",
                "transport": "streamable_http",
                "headers": {
                    "Authorization": f"Bearer {github_token}"}
            }

        # Generate share script for the agent
        share_script = generate_chatbot_share_script(user_id, DEFAULT_WORKSPACE_ID, chatbot_id)

        agent_data = {
            'agent_id': agent_id,
            'agent_name': agent_name,
            'provider_name': provider_name,  # Store provider
            'model_name': model_name,
            'mcp_config': mcp_config,
            'github_token': github_token if mcp_github_enabled else None,
            'system_prompt': system_prompt,
            'created_by': user_id,
            'created_at': firestore.SERVER_TIMESTAMP if FIREBASE_ENABLED else datetime.now().isoformat(),
            'agent_url': f"https://dynamic-ui-chatbot.web.app/#/chats?clientId={user_id}&workspaceId={DEFAULT_WORKSPACE_ID}&chatbotId={chatbot_id}",
            'chatbot_id': chatbot_id,
            'share_script': share_script
        }

        # Generate chatbot document data with agent configuration
        chatbot_data = generate_chatbot_data(
            user_id,
            DEFAULT_WORKSPACE_ID,
            chatbot_id,
            agent_name,
            provider_name,  # Pass provider
            model_name,
            mcp_github_enabled,
            github_token,
            system_prompt
        )

        if FIREBASE_ENABLED:
            # Save agent to agents collection
            db.collection('agents').document(agent_id).set(agent_data)

            # Create chatbot document inside workspace
            # Path: g_users/{user_id}/workspaces/{DEFAULT_WORKSPACE_ID}/chatbots/{chatbot_id}
            chatbot_data['timestamp'] = firestore.SERVER_TIMESTAMP
            db.collection('g_users').document(user_id).collection('workspaces').document(
                DEFAULT_WORKSPACE_ID).collection('chats').document(chatbot_id).set(chatbot_data)
        else:
            mock_agents[agent_id] = agent_data

            # Store chatbot in mock workspace
            for user_email, user_data in mock_users.items():
                if user_data['user_id'] == user_id:
                    if 'chats' not in user_data['workspaces'][DEFAULT_WORKSPACE_ID]:
                        user_data['workspaces'][DEFAULT_WORKSPACE_ID]['chats'] = {}
                    chatbot_data['timestamp'] = datetime.now()
                    user_data['workspaces'][DEFAULT_WORKSPACE_ID]['chats'][chatbot_id] = chatbot_data
                    break

        success_msg = f"✅ Agent '{agent_name}' created successfully with {provider_name} {model_name}!"
        return True, success_msg, chatbot_id, share_script

    except Exception as e:
        return False, f"Failed to create agent: {str(e)}", None, None


def get_user_agents(user_id):
    """
    Get all agents/chatbots created by a user, sorted by timestamp descending (newest first)
    Returns: list of agent info strings
    """
    if not user_id:
        return []

    try:
        if FIREBASE_ENABLED:
            # Fetch chatbots from the workspace subcollection, ordered by timestamp descending
            # Path: g_users/{user_id}/workspaces/{DEFAULT_WORKSPACE_ID}/chats
            chatbots = db.collection('g_users').document(user_id).collection('workspaces').document(
                DEFAULT_WORKSPACE_ID).collection('chats').order_by('timestamp',
                                                                   direction=firestore.Query.DESCENDING).get()
            agent_list = []
            for chatbot in chatbots:
                data = chatbot.to_dict()
                chatbot_id = data.get('id', chatbot.id)
                chatbot_name = data.get('chatbotName', 'Unnamed Agent')
                # provider = data.get('provider', 'Unknown')  # Get provider
                # model = data.get('model', 'Unknown')  # Get model
                timestamp = data.get('timestamp', None)
                share_script = data.get('shareScript', '')

                # --- Extract provider & model safely ---
                chat_message_models = data.get("chatMessageModels", [])

                if chat_message_models and isinstance(chat_message_models, list):
                    llm_data = chat_message_models[0].get("llm", {})
                    provider = llm_data.get("provider", "Unknown")
                    model = llm_data.get("model", "Unknown")
                else:
                    provider = "Unknown"
                    model = "Unknown"

                # Format timestamp if available
                timestamp_str = ""
                if timestamp:
                    try:
                        timestamp_str = f"   Created: {timestamp.strftime('%Y-%m-%d %H:%M')}\n"
                    except:
                        pass

                agent_url = f"https://dynamic-ui-chatbot.web.app/#/individual_chat_screen?clientId={user_id}&workspaceId={DEFAULT_WORKSPACE_ID}&chatbotId={chatbot_id}"

                # Format with provider, model, timestamp, and shareScript info
                agent_info = f"🤖 {chatbot_name}\n"
                agent_info += f"   Provider: {provider} | Model: {model}\n"
                if timestamp_str:
                    agent_info += timestamp_str
                agent_info += f"   URL: {agent_url}\n"
                agent_info += f"   📋 Share Script:\n{share_script}"
                agent_list.append(agent_info)
            return agent_list
        else:
            agent_list = []
            for user_email, user_data in mock_users.items():
                if user_data['user_id'] == user_id:
                    workspaces = user_data.get('workspaces', {})
                    default_workspace = workspaces.get(DEFAULT_WORKSPACE_ID, {})
                    chatbots = default_workspace.get('chats', {})

                    # Sort chatbots by timestamp descending (newest first)
                    sorted_chatbots = sorted(
                        chatbots.items(),
                        key=lambda x: x[1].get('timestamp', datetime.min),
                        reverse=True
                    )

                    for chatbot_id, data in sorted_chatbots:
                        chatbot_name = data.get('chatbotName', 'Unnamed Agent')
                        provider = data.get('provider', 'Unknown')
                        model = data.get('model', 'Unknown')
                        timestamp = data.get('timestamp', None)
                        share_script = data.get('shareScript', '')

                        # Format timestamp if available
                        timestamp_str = ""
                        if timestamp:
                            try:
                                timestamp_str = f"   Created: {timestamp.strftime('%Y-%m-%d %H:%M')}\n"
                            except:
                                pass

                        agent_url = f"https://dynamic-ui-chatbot.web.app/#/individual_chat_screen?clientId={user_id}&workspaceId={DEFAULT_WORKSPACE_ID}&chatbotId={chatbot_id}"

                        # Format with provider, model, timestamp, and shareScript info
                        agent_info = f"🤖 {chatbot_name}\n"
                        agent_info += f"   Provider: {provider} | Model: {model}\n"
                        if timestamp_str:
                            agent_info += timestamp_str
                        agent_info += f"   URL: {agent_url}\n"
                        agent_info += f"   📋 Share Script:\n{share_script}"
                        agent_list.append(agent_info)
                    break
            return agent_list

    except Exception as e:
        print(f"Error fetching agents: {e}")
        return []


def get_user_by_id(user_id):
    """
    Get user data by user ID
    Returns: user data dict or None
    """
    try:
        if FIREBASE_ENABLED:
            user_doc = db.collection('g_users').document(user_id).get()
            if user_doc.exists:
                return user_doc.to_dict()
            return None
        else:
            for email, data in mock_users.items():
                if data['user_id'] == user_id:
                    return data
            return None

    except Exception as e:
        print(f"Error fetching user: {e}")
        return None


def get_user_workspace(user_id):
    """
    Get user's default workspace
    Returns: workspace data dict or None
    """
    try:
        if FIREBASE_ENABLED:
            # Path: g_users/{user_id}/workspaces/{DEFAULT_WORKSPACE_ID}
            workspace_doc = db.collection('g_users').document(user_id).collection('workspaces').document(
                DEFAULT_WORKSPACE_ID).get()
            if workspace_doc.exists:
                return workspace_doc.to_dict()
            return None
        else:
            for user_email, user_data in mock_users.items():
                if user_data['user_id'] == user_id and 'workspaces' in user_data:
                    return user_data['workspaces'].get(DEFAULT_WORKSPACE_ID)
            return None

    except Exception as e:
        print(f"Error fetching workspace: {e}")
        return None