import streamlit as st
from PIL import Image, UnidentifiedImageError
import io
import uuid
import urllib.parse
import pytz
from datetime import datetime
from ocr_engine import extract_weight_from_image  # Make sure this returns (weight, confidence)

# Setup
st.set_page_config(page_title="⚖️ Auto Weight Logger", layout="centered")
st.title("⚖️ Auto Weight Logger")

# Session states
if "camera_key" not in st.session_state:
    st.session_state.camera_key = str(uuid.uuid4())

# Input method
input_mode = st.radio("📸 Select Input Method", ["Camera", "Upload"], horizontal=True)

# Clear button
if st.button("🔁 Clear / Retake"):
    st.session_state.camera_key = str(uuid.uuid4())
    st.rerun()

# Image bytes and capture
image_bytes = None
image = None

if input_mode == "Camera":
    cam_photo = st.camera_input("📷 Capture weight display", key=st.session_state.camera_key)
    if cam_photo:
        image_bytes = cam_photo.getvalue()

elif input_mode == "Upload":
    uploaded_file = st.file_uploader("📁 Upload Image (JPG/PNG)", type=["jpg", "jpeg", "png"])
    if uploaded_file:
        image_bytes = uploaded_file.read()

# Process image
if image_bytes:
    try:
        image = Image.open(io.BytesIO(image_bytes))

        # Timestamp
        ist = pytz.timezone("Asia/Kolkata")
        captured_time = datetime.now(ist).strftime("%Y-%m-%d %I:%M:%S %p")

        st.subheader("🖼️ Snapshot Image")
        st.image(image, use_column_width=True)

        if len(image_bytes) > 5 * 1024 * 1024:
            st.error("❌ Image too large (>5MB). Please use a smaller image.")
            st.stop()

        with st.spinner("🔍 Extracting weight..."):
            weight, confidence = extract_weight_from_image(image)

        # Output regardless of confidence
        st.markdown(f"### 📦 Captured Weight: `{weight if weight else 'Not Detected'}`")
        st.markdown(f"### 🕒 Captured At (IST): `{captured_time}`")

        if not weight or confidence < 80:
            st.warning(f"⚠️ Low OCR Confidence ({int(confidence)}%). You may retry.")
        else:
            st.success(f"✅ High Confidence: {int(confidence)}%")

        # Salesforce redirect link
        device_id = "BAL-001"
        image_url = ""  # optional

        salesforce_url = (
            "https://autoweightlogger-dev-ed.my.salesforce-sites.com/"
            f"weight_logger_page?WeightInput={urllib.parse.quote(str(weight))}"
            f"&DeviceID={urllib.parse.quote(device_id)}&ImageURL={urllib.parse.quote(image_url)}"
        )

        st.markdown("### ✅ Send to Salesforce")
        st.markdown(f"[📤 Click to Log Weight in Salesforce]({salesforce_url})", unsafe_allow_html=True)

    except UnidentifiedImageError:
        st.error("❌ Invalid image format.")
    except Exception as e:
        st.error("❌ Something went wrong while processing the image.")
        st.exception(e)