import os
import zipfile
import io
from flask import Flask, render_template, request, send_file, after_this_request
from PIL import Image, ImageDraw, ImageFont, ImageOps
import tempfile
import shutil
import time

app = Flask(__name__)
app.config['MAX_CONTENT_LENGTH'] = 50 * 1024 * 1024  # 50MB limit

def process_image(img, options):
    # 1. Strip EXIF (by creating a new image)
    if options.get('strip_exif'):
        data = list(img.getdata())
        image_without_exif = Image.new(img.mode, img.size)
        image_without_exif.putdata(data)
        img = image_without_exif

    # 2. Resize
    resize_mode = options.get('resize_mode')
    if resize_mode == 'percentage':
        scale = int(options.get('resize_value', 100)) / 100.0
        if scale != 1.0:
            new_size = (int(img.width * scale), int(img.height * scale))
            img = img.resize(new_size, Image.Resampling.LANCZOS)
    elif resize_mode == 'width':
        target_width = int(options.get('resize_value', img.width))
        if target_width != img.width:
            ratio = target_width / img.width
            new_size = (target_width, int(img.height * ratio))
            img = img.resize(new_size, Image.Resampling.LANCZOS)

    # 3. Watermark
    watermark_text = options.get('watermark_text')
    if watermark_text:
        # Create a transparent layer
        txt_layer = Image.new('RGBA', img.size, (255, 255, 255, 0))
        draw = ImageDraw.Draw(txt_layer)
        
        # Calculate font size (relative to image width)
        fontsize = int(img.width / 20)
        if fontsize < 10: fontsize = 10
        
        try:
            # Try to load a default font, otherwise load default
            # On Linux/Docker, paths might differ. 
            # We'll use default bitmap font if TTF not found or just try-except
            font = ImageFont.truetype("DejaVuSans.ttf", fontsize)
        except IOError:
            font = ImageFont.load_default()
            
        # Position: Bottom Right with padding
        # Get text size
        bbox = draw.textbbox((0, 0), watermark_text, font=font)
        textwidth = bbox[2] - bbox[0]
        textheight = bbox[3] - bbox[1]
        
        padding = 10
        x = img.width - textwidth - padding
        y = img.height - textheight - padding
        
        # Draw semi-transparent text
        draw.text((x, y), watermark_text, font=font, fill=(255, 255, 255, 128))
        
        if img.mode != 'RGBA':
            img = img.convert('RGBA')
            
        img = Image.alpha_composite(img, txt_layer)

    # 4. Format Conversion handled during save
    return img

@app.route('/', methods=['GET'])
def index():
    return render_template('index.html')

@app.route('/process', methods=['POST'])
def process():
    if 'files' not in request.files:
        return "No files uploaded", 400
    
    files = request.files.getlist('files')
    if not files or files[0].filename == '':
        return "No files selected", 400

    # Get options
    target_format = request.form.get('target_format', 'original')
    resize_mode = request.form.get('resize_mode', 'none') # none, percentage, width
    resize_value = request.form.get('resize_value', 0)
    watermark_text = request.form.get('watermark_text', '').strip()
    strip_exif = 'strip_exif' in request.form
    
    options = {
        'resize_mode': resize_mode,
        'resize_value': resize_value,
        'watermark_text': watermark_text,
        'strip_exif': strip_exif
    }

    # Create a temporary directory for processing
    temp_dir = tempfile.mkdtemp()
    
    try:
        zip_buffer = io.BytesIO()
        with zipfile.ZipFile(zip_buffer, 'w', zipfile.ZIP_DEFLATED) as zip_file:
            for file in files:
                if not file.filename:
                    continue
                
                try:
                    img = Image.open(file.stream)
                    
                    # Process
                    img = process_image(img, options)
                    
                    # Determine output filename and format
                    original_name = os.path.splitext(file.filename)[0]
                    ext = os.path.splitext(file.filename)[1].lower()
                    
                    if target_format != 'original':
                        ext = '.' + target_format.lower()
                        if target_format.lower() == 'jpeg':
                            img = img.convert('RGB')
                        elif target_format.lower() == 'png':
                            # Keep RGBA if possible, or convert if needed
                            pass
                    
                    # Save to temp buffer
                    img_byte_arr = io.BytesIO()
                    save_format = ext.strip('.').upper()
                    if save_format == 'JPG': save_format = 'JPEG'
                    
                    # Handle WEBP/JPEG quality if needed (using default for now)
                    img.save(img_byte_arr, format=save_format)
                    
                    # Add to ZIP
                    zip_file.writestr(f"processed/{original_name}{ext}", img_byte_arr.getvalue())
                    
                except Exception as e:
                    print(f"Error processing {file.filename}: {e}")
                    # Optionally add an error log to the zip
                    zip_file.writestr(f"processed/errors/{file.filename}.txt", str(e))

        zip_buffer.seek(0)
        
        # Cleanup temp dir (we didn't actually write files to disk, just memory, 
        # but if we did, we'd clean here. The `img_byte_arr` approach avoids disk IO)
        
        return send_file(
            zip_buffer,
            mimetype='application/zip',
            as_attachment=True,
            download_name=f'processed_images_{int(time.time())}.zip'
        )

    finally:
        shutil.rmtree(temp_dir)

if __name__ == '__main__':
    port = int(os.environ.get('PORT', 7860))
    app.run(host='0.0.0.0', port=port)