import gradio as gr
from pdf2image import convert_from_path
from PIL import Image
import pytesseract

# UPDATED: 'eng' added for mixed words like "Mean", "Statistics"
OCR_LANG = "guj+eng"

def extract_gujarati_text(pdf_file, page_number):
    if pdf_file is None:
        return "Please upload a PDF file first.", None
        
    try:
        # Convert PDF page to image
        images = convert_from_path(pdf_file.name, first_page=page_number, last_page=page_number)
        image = images[0]
        
        # Configuration for better block handling (helps with textbook layouts)
        custom_config = r'--oem 3 --psm 3'
        
        text = pytesseract.image_to_string(image, lang=OCR_LANG, config=custom_config)
        return text, image
        
    except Exception as e:
        return f"Error: {str(e)}", None

# CSS to ensure the image and text box are roughly the same height for easy comparison
css = """
.gradio-container {min-height: 0px !important;}
#img_out {height: 80vh !important;} 
#txt_out textarea {height: 80vh !important;}
"""

with gr.Blocks(css=css, theme=gr.themes.Soft()) as demo:
    gr.Markdown("## 📚 Side-by-Side Gujarati OCR (Textbook Mode)")
    
    # Input Section at the top
    with gr.Row(variant="panel"):
        with gr.Column(scale=1):
            pdf = gr.File(label="1. Upload PDF", file_types=[".pdf"])
        with gr.Column(scale=1):
            page = gr.Number(label="2. Page Number", minimum=1, value=1, step=1)
            button = gr.Button("3. Extract Text & Compare", variant="primary", size="lg")

    # Output Section: Side-by-Side Comparison
    with gr.Row():
        with gr.Column(scale=1):
            # Left: Original Image
            image_output = gr.Image(label="📄 Original Page Snapshot", type="pil", elem_id="img_out")
        
        with gr.Column(scale=1):
            # Right: Extracted Text
            text_output = gr.Textbox(
                label="📝 Extracted Text (Editable)", 
                elem_id="txt_out",
                show_copy_button=True,
                interactive=True 
            )

    button.click(fn=extract_gujarati_text, inputs=[pdf, page], outputs=[text_output, image_output])

demo.launch()