import torch
import transformers
import gradio as gr
import pandas as pd
import numpy as np
from sklearn.model_selection import train_test_split
from sklearn.metrics.pairwise import cosine_similarity
from linkedin_api import Linkedin
import os
from dotenv import load_dotenv
import re
from typing import List, Dict
from linkedin_v2 import linkedin
from transformers import AutoTokenizer, AutoModel 


class LinkedInResumeScreeningApp:
    def __init__(self):
        # Load LinkedIn credentials from environment variables
        load_dotenv()
        self.linkedin_client_id = os.getenv('77sd5p8vsgyf2w')
        self.linkedin_client_secret = os.getenv('WPL_AP1.q9WCdX7Yf1z6YmEy.guv26Q==')
        self.linkedin_redirect_uri = os.getenv('https://www.linkedin.com/in/anupam-joshi-980840290/')
        
        # Debug logging
        print("LinkedIn Credentials Status:")
        print(f"Client ID exists: {bool(self.linkedin_client_id)}")
        print(f"Client Secret exists: {bool(self.linkedin_client_secret)}")
        print(f"Redirect URI exists: {bool(self.linkedin_redirect_uri)}")
        
        # We also need an access token
        self.access_token = os.getenv('AQVF8Ec70U1Qyajgk1Czv8Mk0WD8fs-PtWhPgFbxfGoUTFMy3XT8OmYkzx3riZNeIf-HJGMubPz6RVABfYV1JkGCHxUOfvddCsYHcwHLJ9mzTHCNag8Knkrf3ywzp1GowBxaSssi6lgnC01VfyAaN_qiC1RlJwEya2gEHRDkEHaYbb70tSjSx2Zk1yFPUiXO-uvG0AsDR0mGuBtf0nzkbEYnzAsEuhtMnUo3NGZhc8tzNgCKga6t7NOJ5aha7XmWo3M-P0rruGUeiVsfuM_wF2NnGv1wqICUuUNZ1t4MZbOJzfEhrBgsqu7fKp5MvQD8oSvHzX75t3R8m_dg-oSfFCo7GKS7xg')
        print(f"Access Token exists: {bool(self.access_token)}")
        
        if not all([self.linkedin_client_id, self.linkedin_client_secret, 
                   self.linkedin_redirect_uri, self.access_token]):
            print("WARNING: Some LinkedIn credentials are missing!")
        
        # Demo mode for testing without LinkedIn API
        self.demo_mode = not all([self.linkedin_client_id, self.linkedin_client_secret, self.linkedin_redirect_uri])
        
        # Sample profiles for demo mode
        self.demo_profiles = [
            {
                'name': 'John Smith',
                'headline': 'Senior Data Scientist at Tech Corp',
                'email': 'john.smith@example.com',
                'profile_url': 'https://linkedin.com/in/john-smith',
                'skills': ['Python', 'Machine Learning', 'TensorFlow', 'Deep Learning', 'NLP'],
                'experience': 'Senior Data Scientist at Tech Corp: Leading ML projects\nData Scientist at AI Solutions: Developed predictive models'
            },
            {
                'name': 'Sarah Johnson',
                'headline': 'Full Stack Developer | React | Node.js',
                'email': 'sarah.j@example.com',
                'profile_url': 'https://linkedin.com/in/sarah-johnson',
                'skills': ['React', 'Node.js', 'TypeScript', 'AWS', 'Docker'],
                'experience': 'Full Stack Developer at Web Solutions: Building scalable applications\nFrontend Developer at StartupX: Developed React applications'
            },
            {
                'name': 'Michael Chen',
                'headline': 'Machine Learning Engineer | AI Researcher',
                'email': 'michael.c@example.com',
                'profile_url': 'https://linkedin.com/in/michael-chen',
                'skills': ['PyTorch', 'Computer Vision', 'Deep Learning', 'Python', 'MLOps'],
                'experience': 'ML Engineer at AI Labs: Developing CV models\nResearch Scientist at Tech University: Published papers on deep learning'
            }
        ]
        
        try:
            # Initialize LinkedIn API client
            self.authentication = linkedin.LinkedInAuthentication(
                self.linkedin_client_id,
                self.linkedin_client_secret,
                self.linkedin_redirect_uri,
                ['r_liteprofile', 'r_emailaddress', 'w_member_social']
            )
            
            if self.access_token:
                self.authentication.token = self.access_token
                print("Successfully set LinkedIn access token")
            else:
                print("No access token found - authentication will fail")
                
            # Test the connection
            self.linkedin = linkedin.LinkedInApplication(self.authentication)
            print("LinkedIn API connection initialized successfully")
            
        except Exception as e:
            print(f"Error initializing LinkedIn API: {str(e)}")
            print("Falling back to demo mode")
        
        # Load access token if available
        self.access_token = os.getenv('LINKEDIN_ACCESS_TOKEN')
        if self.access_token:
            self.authentication.token = self.access_token
            
        self.linkedin = linkedin.LinkedInApplication(self.authentication)
        
        # Load pre-trained model for embedding generation
        self.tokenizer = AutoTokenizer.from_pretrained('sentence-transformers/all-MiniLM-L6-v2')
        self.model = AutoModel.from_pretrained('sentence-transformers/all-MiniLM-L6-v2')
        
        # Initialize cache for LinkedIn profiles
        self.profile_cache = {}

    def search_linkedin_profiles(self, keywords: str, limit: int = 20) -> List[Dict]:
        """
        Search LinkedIn for profiles matching the given keywords.
        Falls back to demo profiles if LinkedIn API is not configured.
        """
        if self.demo_mode:
            print("Running in demo mode with sample profiles")
            return self.demo_profiles
        try:
            # Search for people on LinkedIn using the v2 API
            search_params = {
                'keywords': keywords,
                'count': limit,
                'facet': 'network,|S,F'
            }
            
            search_results = self.linkedin.search_profile(
                selectors=[
                    'id', 'first-name', 'last-name', 'headline',
                    'public-profile-url', 'email-address'
                ],
                params=search_params
            )
            
            profiles = []
            for profile in search_results.get('people', {}).get('values', []):
                # Format profile data
                formatted_profile = {
                    'name': f"{profile.get('firstName', '')} {profile.get('lastName', '')}",
                    'headline': profile.get('headline', ''),
                    'email': profile.get('emailAddress', ''),
                    'profile_url': profile.get('publicProfileUrl', ''),
                    'skills': self._get_profile_skills(profile.get('id')),
                    'experience': self._get_profile_experience(profile.get('id'))
                }
                
                profiles.append(formatted_profile)
                
            return profiles
        except Exception as e:
            print(f"Error searching LinkedIn profiles: {str(e)}")
            return []

    def _get_profile_skills(self, profile_id: str) -> List[str]:
        """
        Get skills for a specific profile
        """
        try:
            skills = self.linkedin.get_profile(
                profile_id,
                selectors=['skills']
            )
            return [skill['name'] for skill in skills.get('skills', {}).get('values', [])]
        except:
            return []

    def _get_profile_experience(self, profile_id: str) -> str:
        """
        Get formatted experience for a specific profile
        """
        try:
            experience = self.linkedin.get_profile(
                profile_id,
                selectors=['positions']
            )
            
            formatted = []
            for position in experience.get('positions', {}).get('values', []):
                company = position.get('company', {}).get('name', '')
                title = position.get('title', '')
                description = position.get('summary', '')
                formatted.append(f"{title} at {company}: {description}")
                
            return '\n'.join(formatted)
        except:
            return ''

    def screen_candidates(self, job_description: str, keywords: str, limit: int = 10):
        """
        Screen candidates from LinkedIn based on job description
        """
        # Search LinkedIn for matching profiles
        profiles = self.search_linkedin_profiles(keywords, limit)
        
        if not profiles:
            return [{"Error": "No profiles found or LinkedIn API access error"}]
        
        # Generate embeddings for job description and profiles
        job_embed = self.generate_embeddings([job_description])
        
        profile_texts = [
            f"{p['headline']}\n{p['experience']}\n{' '.join(p['skills'])}"
            for p in profiles
        ]
        profile_embeds = self.generate_embeddings(profile_texts)
        
        # Calculate similarities
        similarities = cosine_similarity(job_embed, profile_embeds)[0]
        
        # Sort profiles by similarity
        sorted_indices = similarities.argsort()[::-1]
        
        # Format results
        results = []
        for idx in sorted_indices:
            profile = profiles[idx]
            results.append({
                'Name': profile['name'],
                'Email': profile['email'],
                'Headline': profile['headline'],
                'Profile URL': profile['profile_url'],
                'Similarity Score': f"{similarities[idx]*100:.2f}%"
            })
        
        return results

    def generate_embeddings(self, texts):
        # Generate embeddings for given texts
        with torch.no_grad():
            inputs = self.tokenizer(texts, padding=True, truncation=True, return_tensors='pt', max_length=512)
            outputs = self.model(**inputs)
            embeddings = self._mean_pooling(outputs, inputs['attention_mask'])
        return embeddings

    def _mean_pooling(self, model_output, attention_mask):
        token_embeddings = model_output[0]
        input_mask_expanded = attention_mask.unsqueeze(-1).expand(token_embeddings.size()).float()
        return torch.sum(token_embeddings * input_mask_expanded, 1) / torch.clamp(input_mask_expanded.sum(1), min=1e-9)

    def gradio_interface(self):
        # Create Gradio interface
        iface = gr.Interface(
            fn=self.screen_candidates,
            inputs=[
                gr.Textbox(label="Job Description"),
                gr.Textbox(label="LinkedIn Search Keywords"),
                gr.Slider(minimum=5, maximum=50, value=10, step=5, label="Number of candidates to screen")
            ],
            outputs=gr.JSON(label="Matching Candidates"),
            title="AI Resume Screening with LinkedIn Integration",
            description="Search LinkedIn profiles and match candidates to job descriptions using AI embeddings."
        )
        return iface

# Initialize and launch the app
if __name__ == "__main__":
    app = LinkedInResumeScreeningApp()
    demo = app.gradio_interface()
    demo.launch(debug=True)