import base64
import json
import os
from io import BytesIO
from typing import Optional, Dict, Any

# --- New Dependency ---
# The google-generativeai library is now required.
# Please install it using: pip install google-generativeai
try:
    from google import genai
    from google.genai.types import RawReferenceImage
    from google.genai import types
except ImportError:
    print("google-generativeai library not found. Please install it using: pip install google-generativeai")
    exit()

# Pillow is required for image format conversion and normalization.
# Please install it using: pip install Pillow
try:
    from PIL import Image
except ImportError:
    print("Pillow library not found. Please install it using: pip install Pillow")
    exit()

# --- Configuration ---
# It is recommended to set these as environment variables for security.
# For ImgBB: used to upload the final image and get a public URL.
IMGBB_API_KEY = os.getenv("IMGBB_API_KEY")
# For Google AI: your API key for accessing the Gemini model.
GEMINI_API_KEY = os.getenv("GEMINI_API_KEY")

# Configure the Gemini client library
if GEMINI_API_KEY:
    client = genai.Client(api_key=GEMINI_API_KEY)

def upload_to_imgbb(image_path: str, file_name: str) -> Optional[str]:
    """
    Uploads the image at image_path to ImgBB.
    Returns the public URL or None on failure.
    (This function is unchanged from the original script)
    """
    if not IMGBB_API_KEY:
        print("Warning: IMGBB_API_KEY not set, skipping upload to ImgBB.")
        return None

    # requests is now only used for ImgBB uploads, so we import it here.
    import requests
    print(f"Uploading {file_name} to ImgBB...")
    try:
        with open(image_path, 'rb') as f:
            files = {"image": (file_name, f.read())}
        resp = requests.post(
            "https://api.imgbb.com/1/upload",
            params={"key": IMGBB_API_KEY},
            files=files,
            timeout=30
        )
        resp.raise_for_status()
        data = resp.json().get("data", {})
        url = data.get("url")
        if url:
            print(f"Successfully uploaded to ImgBB: {url}")
            return url
        else:
            print(f"Error: ImgBB API response missing 'url'. Response: {resp.json()}")
            return None
    except requests.exceptions.RequestException as e:
        print(f"Error: ImgBB upload failed: {e}")
        return None

def _save_image_bytes(image_bytes: bytes, save_path: str) -> bool:
    """
    Saves raw image bytes to a file.

    Args:
        image_bytes: The raw bytes of the image data.
        save_path: The local path to save the image.

    Returns:
        True if saving was successful, False otherwise.
    """
    print(f"Saving generated image to: {save_path}")
    try:
        with open(save_path, 'wb') as f:
            f.write(image_bytes)
        print("Image successfully saved.")
        return True
    except IOError as e:
        print(f"Error saving image file: {e}")
        return False


def generate_image(
    prompt_text: str,
    image_path: str,
    download_path: Optional[str] = None
) -> Optional[Dict[str, Any]]:
    """
    Sends a request to the Gemini API using the Python SDK to modify an image,
    optionally saves the result, and uploads it to ImgBB.

    Args:
        prompt_text: The instructional text for image modification.
        image_path: The file path to the input image (any common format).
        download_path: If provided, the path to save the generated image.

    Returns:
        A dictionary containing a simplified API response and the ImgBB URL,
        or None on error.
    """
    if not GEMINI_API_KEY:
        print("Error: GEMINI_API_KEY environment variable not set.")
        return None
    
    try:
        # --- Image Loading ---
        print(f"Processing image: {image_path}")
        img = Image.open(image_path)
    except FileNotFoundError:
        print(f"Error: Image file not found at {image_path}")
        return None
    except Exception as e:
        print(f"Error processing image file. Ensure it's a valid image. Details: {e}")
        return None

    try:
        # --- API Call via Python SDK ---
        print("Initializing Gemini model...")
        print("Sending request to Gemini API via Python SDK...")
        # --- Process Gemini API Response ---
        # Convert the PIL Image to bytes (JPEG format)
        img_byte_arr = BytesIO()
        img.save(img_byte_arr, format='JPEG')
        img_bytes = img_byte_arr.getvalue()

        response = client.models.generate_content(
            model='gemini-2.0-flash-preview-image-generation',
            contents=[
                types.Part.from_text(text=prompt_text),
                types.Part.from_bytes(data=img_bytes, mime_type='image/jpeg'),
            ],
            config=types.GenerateContentConfig(
                response_modalities=["TEXT", "IMAGE"]
            )
        )
        # DEBUG: print the response parts to inspect structure
        # print(response.candidates[0].content.parts)

        # Extract the image bytes from the response parts
        generated_image_bytes = None
        for part in response.candidates[0].content.parts:
            if hasattr(part, "inline_data") and part.inline_data and hasattr(part.inline_data, "data"):
                generated_image_bytes = part.inline_data.data
                break
        print(generated_image_bytes)
        imgbb_url = None
        # --- Download & Upload Logic ---
        if download_path and generated_image_bytes:
            if _save_image_bytes(generated_image_bytes, download_path):
                # If save is successful, upload the saved file to ImgBB
                file_name = os.path.basename(download_path)
                imgbb_url = upload_to_imgbb(download_path, file_name)
        
        # Prepare a final dictionary similar to the original script's output
        final_result = {
            "api_response": {
                "candidates": [{
                    "finish_reason": response.candidates[0].finish_reason.name
                }]
            },
            "imgbb_url": imgbb_url
        }
        return final_result

    except Exception as e:
        print(f"Gemini API request failed: {e}")
        return None