"""Core resume analysis logic"""
import streamlit as st
import re
from models.llm_client import LLMClient
from agents.resume_extractor import ResumeExtractor
from agents.jd_summarizer import JobDescriptionSummarizer
from agents.matcher import ResumeJDMatcher
from agents.shortlister import Shortlister
from db.database import ResumeMatchDB

def extract_candidate_info(resume_text):
    """Extract candidate name and email from resume text"""
    email_pattern = r'[\w\.-]+@[\w\.-]+\.\w+'
    email = re.search(email_pattern, resume_text)
    email = email.group(0) if email else "Not found"
    
    lines = resume_text.split('\n')
    name = "Not found"
    
    name_patterns = [
        r'^[A-Z][a-z]+\s+[A-Z][a-z]+$',
        r'^[A-Z][a-z]+\s+[A-Z]\.\s+[A-Z][a-z]+$',
        r'^[A-Z][a-z]+\s+[A-Z][a-z]+\s+[A-Z][a-z]+$'
    ]
    
    for line in lines:
        line = line.strip()
        if line and '@' not in line:
            for pattern in name_patterns:
                if re.match(pattern, line):
                    name = line
                    break
            if name != "Not found":
                break
                
    return name, email

def analyze_resumes(uploaded_files, job_descriptions, api_key, model_name, base_url):
    """Analyze resumes and store results in session state"""
    progress_bar = st.progress(0)
    status_text = st.empty()
    
    with st.spinner("Analyzing resumes..."):
        results = []
        total_steps = len(uploaded_files) * len(job_descriptions)
        current_step = 0
        
        db = ResumeMatchDB()
        
        for uploaded_file in uploaded_files:
            status_text.text(f"📄 Processing {uploaded_file.name}...")
            extractor = ResumeExtractor(uploaded_file)
            resume_text = extractor.get_resume_text()
            
            if not resume_text or len(resume_text.strip()) < 10:
                st.error(f"❌ Could not extract text from {uploaded_file.name}. File may be corrupted or empty.")
                continue
            
            candidate_name, candidate_email = extract_candidate_info(resume_text)
            
            candidate_id = db.insert_candidate(
                name=candidate_name,
                email=candidate_email,
                resume_path=uploaded_file.name
            )
            
            resume_results = []
            for jd in job_descriptions:
                current_step += 1
                progress = current_step / total_steps
                progress_bar.progress(progress)
                
                status_text.text(f"🔍 Matching with {jd['title']}...")
                jd_agent = JobDescriptionSummarizer(jd['content'])
                jd_summary = jd_agent.get_summary()
                
                if not jd_summary or len(jd_summary.strip()) < 10:
                    st.error(f"❌ Could not process job description: {jd['title']}")
                    continue
                
                llm = LLMClient(api_key=api_key, model_name=model_name, base_url=base_url)
                matcher = ResumeJDMatcher(llm)
                shortlister = Shortlister(threshold=70.0)
                
                match_result = matcher.match_resume_to_job(resume_text, jd_summary)
                match_percent = shortlister.compute_final_score(match_result)
                is_shortlisted = shortlister.is_shortlisted(match_percent)
                
                job_id = db.insert_job_description(
                    title=jd['title'],
                    description=jd['content']
                )
                
                match_data = {
                    'match_score': match_percent,
                    'skills_match': match_result['skills_match'],
                    'experience_match': match_result['experience_match'],
                    'education_match': match_result['education_match'],
                    'certifications_match': match_result['certifications_match'],
                    'summary': match_result['summary'],
                    'is_shortlisted': is_shortlisted
                }
                db.insert_match_result(candidate_id, job_id, match_data)
                
                resume_results.append({
                    "job_title": jd['title'],
                    "match_score": match_percent,
                    "is_shortlisted": is_shortlisted,
                    "details": match_result,
                    "job_id": job_id
                })
            
            if resume_results:
                best_match = max(resume_results, key=lambda x: x['match_score'])
                
                results.append({
                    "candidate_name": candidate_name,
                    "candidate_email": candidate_email,
                    "resume_name": uploaded_file.name,
                    "best_match": best_match,
                    "candidate_id": candidate_id
                })
        
        progress_bar.empty()
        status_text.empty()
        st.session_state.results = results