import gradio as gr
import os
import traceback
import time


OUTPUT_DIR = "output"
os.makedirs("data", exist_ok=True)
os.makedirs(OUTPUT_DIR, exist_ok=True)
os.makedirs("models", exist_ok=True)

def process_contract(file):
    try:
        # Clearing  previous outputs
        for f in os.listdir(OUTPUT_DIR):
            os.remove(os.path.join(OUTPUT_DIR, f))

        
        if file is None:
            yield " No file uploaded.", None, None, None
            return

        file_path = file.name
        ext = os.path.splitext(file_path)[1].lower()

        if ext not in [".pdf", ".docx"]:
            yield f" Unsupported format: {ext}", None, None, None
            return

        yield " Extracting text...", None, None, None
        time.sleep(0.1)

        # Extract text
        from parser import extract_text_from_pdf, extract_text_from_docx
        text = extract_text_from_pdf(file_path) if ext == ".pdf" else extract_text_from_docx(file_path)

        if not text or len(text.strip()) < 10:
            yield "⚠ Failed to extract meaningful text.", None, None, None
            return

        yield " Finding clauses...", None, None, None
        time.sleep(0.1)

        
        import spacy
        nlp = spacy.load("en_core_web_sm")
        doc = nlp(text)

        
        from spacy_matcher import find_clauses
        matches = find_clauses(text)
        if not matches:
            yield " No clauses detected.", None, None, None
            return

        yield f" Analyzing {len(matches)} clauses with LLM...", None, None, None
        time.sleep(0.1)

        # Analyzeing with LLM
        from llm_reviewer import review_clause_with_llm, get_clause_section
        results = []
        for label, _, start, end in matches:
            section = get_clause_section(doc, start, end, window_size=30)
            review = review_clause_with_llm(label, section)
            results.append({
                "label": label,
                "section": section,
                "review": review
            })

        
        from llm_reviewer import export_to_json, export_to_pdf
        json_path = export_to_json(results, os.path.join(OUTPUT_DIR, "clause_reviews.json"))
        pdf_path = export_to_pdf(results, os.path.join(OUTPUT_DIR, "clause_reviews.pdf"))

        
        output_text = "##  Clause Reviews\n\n"
        for r in results:
            output_text += f" **{r['label'].replace('_', ' ').title()}**\n\n"
            output_text += f" *Excerpt:* {r['section'][:300]}...\n\n"
            output_text += f" *Review:* {r['review']}\n\n---\n\n"

        
        found_types = sorted(set(r['label'].replace('_', ' ').title() for r in results))
        clause_list = ", ".join(found_types)

        
        yield (
            f"Found {len(results)} clauses across {len(found_types)} types:\n\n{clause_list}",
            output_text,
            json_path,
            pdf_path
        )

    except Exception as e:
        tb = traceback.format_exc()
        error_msg = f" Error: {str(e)}\n\n```\n{tb}\n```"
        yield error_msg, None, None, None  


# Gradio Interface 
with gr.Blocks(title="ClauseLens - Legal Contract Analyzer", theme=gr.themes.Soft()) as demo:
    gr.Markdown("#  ClauseLens: Legal Contract Analyzer")
    gr.Markdown("Upload a legal contract (PDF or DOCX) for clause detection and LLM-powered review.")

    with gr.Row():
        file_input = gr.File(label="Upload Contract", file_types=[".pdf", ".docx"])

    with gr.Row():
        btn = gr.Button(" Analyze Contract", variant="primary")

    with gr.Row():
        status = gr.Textbox(label="Status")

    with gr.Row():
        output = gr.Markdown(label="Clause Reviews")

    with gr.Row():
        gr.Markdown("### 📎 Download Reports")

    with gr.Row():
        json_download = gr.File(label="Download JSON Report")
        pdf_download = gr.File(label="Download PDF Report")

    
    btn.click(
        fn=process_contract,
        inputs=file_input,
        outputs=[status, output, json_download, pdf_download]
    )

# Enable queuing for streaming
demo.queue()

if __name__ == "__main__":
    try:
        demo.launch(share=True)
    except Exception as e:
        print(f"Launch failed: {e}")