import streamlit as st
import google.generativeai as genai
from github import Github
from pypdf import PdfReader
import os
from dotenv import load_dotenv

# --- CONFIG ---
st.set_page_config(page_title="DevResume Pro", layout="wide", page_icon="⚡")

# Load Keys
api_key = os.getenv("GEMINI_API_KEY")
github_token = os.getenv("GITHUB_TOKEN")

if not api_key:
    load_dotenv()
    api_key = os.getenv("GEMINI_API_KEY")
    github_token = os.getenv("GITHUB_TOKEN")

# --- FUNC 1: PDF PARSER ---
def extract_pdf_text(file):
    try:
        reader = PdfReader(file)
        text = ""
        for page in reader.pages:
            text += page.extract_text()
        return text
    except:
        return None

# --- FUNC 2: GITHUB CRAWLER ---
def fetch_github_data(username):
    try:
        g = Github(github_token) if github_token else Github()
        user = g.get_user(username)
        repos = sorted(user.get_repos(), key=lambda x: x.stargazers_count, reverse=True)[:4]
        
        repo_data = ""
        for repo in repos:
            readme = "No README"
            try:
                if repo.get_readme().decoded_content:
                    readme = repo.get_readme().decoded_content.decode("utf-8")[:1000]
            except: pass
            
            repo_data += f"Project: {repo.name} ({repo.stargazers_count} Stars, {repo.language})\nDesc: {repo.description}\nContext: {readme}\n\n"
            
        return repo_data
    except Exception as e:
        return f"Error fetching GitHub: {str(e)}"

# --- FUNC 3: THE RESUME ARCHITECT ---
def generate_full_resume(old_resume_text, github_data, target_role):
    genai.configure(api_key=api_key)
    try:
        model = genai.GenerativeModel('gemini-2.5-flash')
    except:
        model = genai.GenerativeModel('gemini-1.5-flash')

    prompt = f"""
    You are an Elite Tech Resume Writer.
    
    SOURCE MATERIAL:
    1. OLD RESUME TEXT:
    {old_resume_text[:4000]}
    
    2. GITHUB PORTFOLIO ANALYSIS:
    {github_data}
    
    TARGET ROLE: {target_role}
    
    TASK:
    Write a complete, SOTA Resume (Markdown Format).
    
    STRUCTURE:
    1. **Header:** Name, Title (Target Role), Links (GitHub/LinkedIn).
    2. **Professional Summary:** Synthesize the old resume + new GitHub achievements into a killer 3-line bio.
    3. **Technical Skills:** Grouped by category (Languages, Frameworks, Tools).
    4. **Featured Projects:** Use the GitHub Data. Write "XYZ Style" impact bullets.
    5. **Experience:** Polish the old resume's experience section. Make it punchy.
    6. **Education:** Keep it simple.
    
    TONE: Senior, High-Impact, Quantified.
    """
    
    try:
        response = model.generate_content(prompt)
        return response.text
    except Exception as e:
        return f"AI Error: {e}"

# --- UI ---
st.title("⚡ DevResume Pro: The Hybrid Architect")
st.markdown("Combines your **Old Resume** + **Real GitHub Code** to build the ultimate portfolio.")

col1, col2 = st.columns([1, 2])

with col1:
    st.subheader("1. Your Inputs")
    gh_user = st.text_input("GitHub Username", placeholder="eatosin")
    role = st.text_input("Target Role", value="Senior AI Engineer")
    uploaded_file = st.file_uploader("Upload Old Resume (PDF)", type="pdf")
    
    if st.button("🚀 Build Resume", type="primary"):
        if not gh_user or not uploaded_file:
            st.error("Please provide both GitHub User and PDF Resume.")
        else:
            with st.spinner("🕵️‍♂️ Reading PDF & Scraping GitHub..."):
                # 1. Read PDF
                pdf_text = extract_pdf_text(uploaded_file)
                
                # 2. Scrape GitHub
                gh_data = fetch_github_data(gh_user)
                
                # 3. Generate
                if pdf_text and gh_data:
                    st.session_state['resume'] = generate_full_resume(pdf_text, gh_data, role)
                else:
                    st.error("Failed to read inputs.")

with col2:
    if 'resume' in st.session_state:
        st.subheader("📄 Your New Resume")
        st.markdown(st.session_state['resume'])
        st.download_button("📥 Download Markdown", st.session_state['resume'], file_name="SOTA_Resume.md")