import os
import threading
from tkinter import Tk, Button, filedialog, messagebox, ttk, Label, Entry, StringVar, Checkbutton, BooleanVar
from PIL import Image

class ImageResizerApp:
    def __init__(self, root):
        self.root = root
        self.root.title("Image Resizer")
        self.root.geometry("450x250")
        self.root.resizable(False, False)

        # Instructions
        Label(root, text="Select images to resize").pack(pady=(10, 5))

        # Frame for size inputs
        size_frame = ttk.Frame(root)
        size_frame.pack(pady=5)

        Label(size_frame, text="Width:").grid(row=0, column=0, padx=(0,5))
        self.width_var = StringVar(value="300")
        Entry(size_frame, textvariable=self.width_var, width=6).grid(row=0, column=1, padx=(0,15))

        Label(size_frame, text="Height:").grid(row=0, column=2, padx=(0,5))
        self.height_var = StringVar(value="300")
        Entry(size_frame, textvariable=self.height_var, width=6).grid(row=0, column=3)

        # Checkbox for convert to webp
        self.convert_var = BooleanVar(value=False)
        Checkbutton(root, text="Convert outputs to .webp (quality=50)", variable=self.convert_var).pack(pady=5)

        # Button to choose images
        Button(root, text="Choose Images", command=self.choose_images).pack(pady=10)

        # Progress bar
        self.progress = ttk.Progressbar(root, orient='horizontal', mode='determinate', length=350)
        self.progress.pack(pady=10)

        # Status label
        self.status_label = Label(root, text="")
        self.status_label.pack()

    def choose_images(self):
        # Validate size inputs before file dialog
        try:
            width = int(self.width_var.get())
            height = int(self.height_var.get())
            if width <= 0 or height <= 0:
                raise ValueError
        except ValueError:
            messagebox.showerror("Invalid size", "Please enter positive integer values for width and height.")
            return

        filetypes = [("Image files", "*.jpg *.jpeg *.png *.webp"), ("All files", "*.*")]
        files = filedialog.askopenfilenames(title="Select images", filetypes=filetypes)
        if files:
            # Disable UI while processing
            self.status_label.config(text="Starting...")
            threading.Thread(target=self.resize_images, args=(files, width, height, self.convert_var.get()), daemon=True).start()

    def resize_images(self, files, target_w, target_h, convert_to_webp):
        total = len(files)
        self.progress["maximum"] = total
        self.progress["value"] = 0
        self.status_label.config(text="Processing...")

        for i, filepath in enumerate(files, start=1):
            try:
                img = Image.open(filepath)
                # Use thumbnail to preserve aspect ratio
                img.thumbnail((target_w, target_h))

                base_dir = os.path.dirname(filepath)
                thumbs_dir = os.path.join(base_dir, "thumbs")
                os.makedirs(thumbs_dir, exist_ok=True)

                orig_name = os.path.basename(filepath)
                name_root, orig_ext = os.path.splitext(orig_name)

                if convert_to_webp:
                    save_name = f"{name_root}.webp"
                    save_path = os.path.join(thumbs_dir, save_name)
                    # Always save as webp with quality=50
                    img.save(save_path, format="WEBP", quality=50)
                else:
                    # Keep original format/extension
                    save_name = orig_name
                    save_path = os.path.join(thumbs_dir, save_name)
                    # Determine format from original extension (Pillow infers from save_path extension)
                    # For safety, specify format explicitly for common cases
                    ext_lower = orig_ext.lower()
                    if ext_lower in [".jpg", ".jpeg"]:
                        img.save(save_path, format="JPEG")
                    elif ext_lower == ".png":
                        img.save(save_path, format="PNG")
                    elif ext_lower == ".webp":
                        img.save(save_path, format="WEBP")
                    else:
                        # Let PIL infer or default to PNG
                        try:
                            img.save(save_path)
                        except Exception:
                            # fallback to PNG
                            fallback = os.path.join(thumbs_dir, f"{name_root}.png")
                            img.save(fallback, format="PNG")
                # End try saving
            except Exception as e:
                print(f"Failed to process {filepath}: {e}")

            # Update progress bar
            self.progress["value"] = i
            self.root.update_idletasks()

        self.status_label.config(text="Done!")
        messagebox.showinfo("Complete", f"Processed {total} images.\nSaved thumbnails in 'thumbs' folders.")

if __name__ == "__main__":
    # Check for Pillow import
    try:
        from PIL import Image
    except ImportError:
        messagebox.showerror("Missing Dependency", "Please install Pillow: pip install pillow")
        exit(1)

    root = Tk()
    app = ImageResizerApp(root)
    root.mainloop()