import gradio as gr
import anthropic
import pdfplumber
import os

# Zero-data-retention client — Anthropic will not store or use uploaded content
client = anthropic.Anthropic(
    api_key=os.environ.get("ANTHROPIC_API_KEY"),
    default_headers={
        "anthropic-beta": "zero-data-retention-1"
    }
)

PRIVACY_NOTICE = """
### 🔒 Privacy & Data Security

**Your documents are protected:**
- Documents are processed in memory only — never stored on our servers
- All processing uses Anthropic's API with **zero-data-retention** enabled — your content is not stored or used for AI training
- Uploaded files are discarded immediately after extraction
- No database, no logs, no third-party sharing

**You retain full control:** This tool extracts and displays data on your screen only. Nothing is saved anywhere.

⚠️ *Always verify AI-extracted fields before submitting to customs authorities. This tool is AI-assisted — final responsibility for all customs declarations remains with the licensed broker or importer.*
"""

def extract_from_invoice(pdf_file):
    if pdf_file is None:
        return "Please upload a PDF invoice."

    # Extract text from PDF — processed in memory only
    text = ""
    with pdfplumber.open(pdf_file.name) as pdf:
        for page in pdf.pages:
            text += page.extract_text() or ""

    if not text.strip():
        return "Could not extract text from this PDF. It may be a scanned image — please try a text-based PDF."

    response = client.messages.create(
        model="claude-sonnet-4-6",
        max_tokens=1024,
        system=(
            "You are an expert at extracting structured data from trade documents "
            "for customs declarations. Be precise and thorough."
        ),
        messages=[{
            "role": "user",
            "content": f"""Extract these customs fields from the invoice below.
If a field is not found, write NOT FOUND.

Fields to extract:
- Shipper name and address
- Consignee name and address
- Invoice number
- Invoice date
- HS Code(s)
- Description of goods
- Declared value and currency
- Country of origin
- Net weight
- Gross weight

Invoice text:
{text[:4000]}

⚠️ AI-assisted extraction — verify all fields before submitting to customs authorities."""
        }]
    )
    return response.content[0].text


with gr.Blocks(theme=gr.themes.Soft(), title="Trade Document Intelligence") as demo:
    gr.Markdown("# Trade Document Intelligence")
    gr.Markdown(
        "AI-powered extraction of customs fields from commercial invoices. "
        "Built for customs brokers and freight forwarders worldwide."
    )

    with gr.Accordion("🔒 Privacy & Data Security — click to read before uploading", open=False):
        gr.Markdown(PRIVACY_NOTICE)

    with gr.Row():
        with gr.Column():
            pdf_input = gr.File(
                label="Upload Commercial Invoice (PDF)",
                file_types=[".pdf"]
            )
            submit_btn = gr.Button("Extract Customs Fields", variant="primary")
            clear_btn = gr.Button("Clear", variant="secondary")

        with gr.Column():
            output = gr.Textbox(
                label="Extracted Customs Fields",
                lines=25,
                placeholder="Extracted fields will appear here after upload..."
            )

    submit_btn.click(fn=extract_from_invoice, inputs=pdf_input, outputs=output)
    clear_btn.click(fn=lambda: (None, ""), outputs=[pdf_input, output])

    gr.Markdown(
        "---\n"
        "*Trade Document Intelligence — AI-assisted customs data extraction. "
        "Built for customs brokers and freight forwarders worldwide.*\n\n"
        "[Terms of Service](https://github.com/tradedocs-ai/trade-document-intelligence/blob/main/docs/TERMS.md)"
    )

demo.launch()