import io
import zipfile
import qrcode
import pandas as pd
from flask import Blueprint, render_template, request, send_file, flash, redirect, url_for
from PIL import Image, ImageDraw, ImageFont
from blueprints.auth import login_required
from rechten import recht_vereist  # Zorg dat dit pad klopt naar je auth_utils.py

# definieren blueprint
qr_code_bp = Blueprint('qr_generator', __name__, template_folder='templates')

def generate_qr_images(excel_file, show_top, show_bottom):
    # Overslaan van de header rij
    df = pd.read_excel(excel_file, header=0) 
    
    zip_buffer = io.BytesIO()
    
    try:
        # Try loading your local or system Arial font
        font = ImageFont.truetype("arial.ttf", 20)
    except IOError:
        try:

            font = ImageFont.load_default_font(size=20)
        except AttributeError:
            # Absolute fallback if Pillow is outdated, but textbbox WILL fail if this hits
            font = ImageFont.load_default()

    with zipfile.ZipFile(zip_buffer, "a", zipfile.ZIP_DEFLATED) as zip_file:
        for index, row in df.iterrows():
            # Gebruik .iloc voor veiligheid tegen kolomnamen
            qr_text = str(row.iloc[0]) if not pd.isna(row.iloc[0]) else ""
            top_text = str(row.iloc[1]) if not pd.isna(row.iloc[1]) else ""
            bottom_text = str(row.iloc[2]) if not pd.isna(row.iloc[2]) else ""
            
            if qr_text.strip() == "":
                continue
            
            qr = qrcode.QRCode(error_correction=qrcode.constants.ERROR_CORRECT_H)
            qr.add_data(qr_text)
            qr.make(fit=True)
            qr_img = qr.make_image(fill_color="black", back_color="white").convert("RGB")
            
            qr_width, qr_height = qr_img.size
            padding = 40
            total_height = qr_height + (2 * padding)
            
            canvas = Image.new("RGB", (qr_width + 40, total_height + 40), "white")
            draw = ImageDraw.Draw(canvas)
            
            qr_x = (canvas.width - qr_width) // 2
            qr_y = padding
            canvas.paste(qr_img, (qr_x, qr_y))
            
            if show_top and top_text:
                bbox = draw.textbbox((0, 0), top_text, font=font)
                text_w = bbox[2] - bbox[0]
                draw.text(((canvas.width - text_w) / 2, 5), top_text, fill="black", font=font)

            if show_bottom and bottom_text:
                bbox = draw.textbbox((0, 0), bottom_text, font=font)
                text_w = bbox[2] - bbox[0]
                draw.text(((canvas.width - text_w) / 2, qr_y + qr_height + 5), bottom_text, fill="black", font=font)
            
            img_io = io.BytesIO()
            canvas.save(img_io, 'PNG')
            img_io.seek(0)
            zip_file.writestr(f"qr_{index+1}.png", img_io.getvalue())

    zip_buffer.seek(0)
    return zip_buffer

@qr_code_bp.route('/')
@login_required
@recht_vereist('qr_codes')
def qr_generator():

    return render_template('qr_code.html')

@qr_code_bp.route('/download-template')
@login_required
@recht_vereist('qr_codes')
def download_template():
    df = pd.DataFrame(columns=["QR-Code (Link/ID)", "Koptekst", "Voettekst"])
    
    buffer = io.BytesIO()
    with pd.ExcelWriter(buffer, engine='openpyxl') as writer:
        df.to_excel(writer, index=False)
    
    buffer.seek(0)
    
    return send_file(
        buffer,
        as_attachment=True,
        download_name='sjabloon_qr.xlsx',
        mimetype='application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'
    )

@qr_code_bp.route('/upload', methods=['POST'])
@login_required
@recht_vereist('qr_codes')
def upload_file():
    if 'file' not in request.files:
        flash("Geen bestand geselecteerd", "warning")
        return redirect(url_for('qr_generator.qr_generator'))
    
    file = request.files['file']
    show_top = request.form.get('show_top') == 'on'
    show_bottom = request.form.get('show_bottom') == 'on'

    if file and file.filename != '':
        try:
            zip_data = generate_qr_images(file, show_top, show_bottom)
            return send_file(
                zip_data,
                mimetype='application/zip',
                as_attachment=True,
                download_name='qr_codes.zip'
            )
        except Exception as e:
            flash(f"Fout bij verwerken: {str(e)}", "danger")
            return redirect(url_for('qr_generator.qr_generator'))
            
    return redirect(url_for('qr_generator.qr_generator'))