import streamlit as st
from resume_parsing import parse_resume_with_llm
from database_integration import save_candidate, save_job, delete_candidate, delete_job, session, Candidate, Job
from chroma_utils import add_to_job_chroma, get_all_jobs_from_chroma, delete_resume_from_chroma, delete_job_from_chroma
from embedding_utils import generate_embedding
from job_matching import calculate_ats_score
import pandas as pd
import numpy as np
import os
os.environ["HF_HOME"] = "/tmp/huggingface"
os.environ["TRANSFORMERS_CACHE"] = "/tmp/huggingface"
os.environ["SENTENCE_TRANSFORMERS_HOME"] = "/tmp/huggingface"
os.environ["STREAMLIT_SERVER_FILE_WATCHER_TYPE"] = "none"



st.set_page_config(page_title="ATS System", layout="wide")

st.title("📄 ATS System Dashboard")

tabs = st.tabs(["Upload Resume", "Post Job", "Match Candidates", "Delete Resume/Job"])

# ---------------- Upload Resume ---------------- #
with tabs[0]:
    st.header("Upload Candidate Resume")
    name = st.text_input("Candidate Name")
    location = st.text_input("Location")
    uploaded_file = st.file_uploader("Upload PDF/DOCX Resume", type=["pdf", "docx"])

    if st.button("Submit Resume"):
        if not uploaded_file:
            st.error("Please upload a resume file.")
        elif not name or not location:
            st.error("Please provide both name and location.")
        else:
            file_type = uploaded_file.name.split(".")[-1]
            resume_content = uploaded_file.read()
            result, embedding = parse_resume_with_llm(resume_content, name, location, file_type)
            if "error" in result:
                st.error(result["error"])
            else:
                save_candidate({
                    "name": name,
                    "location": location,
                    "experience": result.get("experience"),
                    "education": result.get("education"),
                    "skills": result.get("skills")
                }, result["unique_id"])
                st.success(f"Resume uploaded successfully! Candidate ID: {result['unique_id']}")

# ---------------- Post Job ---------------- #
with tabs[1]:
    st.header("Post a New Job")
    job_title = st.text_input("Job Title", key="job_title")
    job_description = st.text_area("Job Description", key="job_description")

    if st.button("Post Job"):
        if not job_title or not job_description:
            st.error("Both job title and description are required.")
        else:
            job_embedding = generate_embedding(job_description)
            metadata = {"title": job_title, "description": job_description}
            unique_id = add_to_job_chroma(job_embedding, metadata)
            save_job(job_title, job_description, unique_id)
            st.success(f"Job posted successfully! Job ID: {unique_id}")

# ---------------- Match Candidates ---------------- #
with tabs[2]:
    st.header("Match Candidates for All Jobs")
    if st.button("Run Matching"):
        job_ids, job_embeddings, job_metadatas = get_all_jobs_from_chroma()
        if not job_ids:
            st.warning("No jobs found in database.")
        else:
            all_results = []
            for i, job_embedding in enumerate(job_embeddings):
                job_embedding = np.array(job_embedding)
                matched_candidates = calculate_ats_score(job_embedding)
                for candidate in matched_candidates:
                    all_results.append({
                        "Job ID": job_ids[i],
                        "Job Title": job_metadatas[i].get("title"),
                        "Candidate ID": candidate["candidate_id"],
                        "Candidate Name": candidate["metadata"]["name"],
                        "Score": round(candidate["score"], 3)
                    })
            if all_results:
                df = pd.DataFrame(all_results)
                st.dataframe(df)
            else:
                st.info("No candidates matched any jobs yet.")

# ---------------- Delete Resume/Job ---------------- #
with tabs[3]:
    st.header("Delete Resume or Job")
    delete_option = st.radio("Select Type to Delete", ["Resume", "Job"])
    unique_id = st.text_input("Enter Unique ID to Delete")

    if st.button("Delete"):
        if not unique_id:
            st.error("Please provide a unique ID.")
        else:
            if delete_option == "Resume":
                delete_resume_from_chroma(unique_id)
                success = delete_candidate(unique_id)
                if success:
                    st.success(f"Resume {unique_id} deleted successfully!")
                else:
                    st.warning("Resume not found.")
            elif delete_option == "Job":
                delete_job_from_chroma(unique_id)
                success = delete_job(unique_id)
                if success:
                    st.success(f"Job {unique_id} deleted successfully!")
                else:
                    st.warning("Job not found.")