import json
import os
import sys
import base64
import subprocess

# Dependency Check
try:
    import requests
except ImportError:
    print("❌ Error: requests library not found.")
    print("👉 Please run: pip install requests pillow")
    sys.exit(1)

try:
    from PIL import Image
except ImportError:
    print("❌ Error: Pillow library not found.")
    print("👉 Please run: pip install requests pillow")
    sys.exit(1)

# ============================================================
# CONFIGURATION — Set your Gemini API key here
# ============================================================
GEMINI_API_KEY = "YOUR_GEMINI_API_KEY_HERE"
# ============================================================

# Paths
SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
BASE_DIR = os.path.dirname(SCRIPT_DIR)
PROMPTS_FILE = os.path.join(SCRIPT_DIR, "image_generation_prompts.json")
RAW_ASSETS_DIR = os.path.join(BASE_DIR, "Raw_Assets")
RESIZE_SCRIPT = os.path.join(SCRIPT_DIR, "resize_assets.py")

# Gemini Imagen API endpoint
IMAGEN_MODEL = "imagen-3.0-generate-001"
IMAGEN_URL = (
    f"https://generativelanguage.googleapis.com/v1beta/models/"
    f"{IMAGEN_MODEL}:predict?key={GEMINI_API_KEY}"
)


def load_prompts():
    """Load image prompts from the JSON config file."""
    if not os.path.exists(PROMPTS_FILE):
        print(f"❌ Error: Prompts file not found: {PROMPTS_FILE}")
        sys.exit(1)
    with open(PROMPTS_FILE, "r", encoding="utf-8") as f:
        data = json.load(f)
    return data.get("images", [])


def generate_image(name, prompt):
    """Call the Gemini Imagen API and return raw PNG bytes, or None on failure."""
    payload = {
        "instances": [{"prompt": prompt}],
        "parameters": {"sampleCount": 1},
    }
    try:
        response = requests.post(IMAGEN_URL, json=payload, timeout=120)
        response.raise_for_status()
    except requests.exceptions.HTTPError as e:
        print(f"   ❌ HTTP error for '{name}': {e}")
        print(f"      Response: {response.text[:300]}")
        return None
    except requests.exceptions.RequestException as e:
        print(f"   ❌ Request failed for '{name}': {e}")
        return None

    result = response.json()
    predictions = result.get("predictions", [])
    if not predictions:
        print(f"   ❌ No predictions returned for '{name}'.")
        return None

    b64_data = predictions[0].get("bytesBase64Encoded")
    if not b64_data:
        print(f"   ❌ No image data in response for '{name}'.")
        return None

    return base64.b64decode(b64_data)


def save_image(name, image_bytes):
    """Save raw bytes as a PNG file in Raw_Assets/."""
    output_path = os.path.join(RAW_ASSETS_DIR, f"{name}.png")
    with open(output_path, "wb") as f:
        f.write(image_bytes)
    return output_path


def run_resize_script():
    """Run resize_assets.py as a subprocess."""
    print("\n🔧 Running resize_assets.py...")
    try:
        result = subprocess.run(
            [sys.executable, RESIZE_SCRIPT],
            check=True,
            capture_output=True,
            text=True,
        )
        print(result.stdout)
        if result.stderr:
            print(result.stderr)
    except subprocess.CalledProcessError as e:
        print(f"❌ resize_assets.py failed: {e}")
        if e.stdout:
            print(e.stdout)
        if e.stderr:
            print(e.stderr)


def main():
    print("🚀 IYmtg Image Generation Pipeline")
    print("=" * 40)

    if GEMINI_API_KEY == "YOUR_GEMINI_API_KEY_HERE":
        print("❌ Error: Gemini API key not set.")
        print("👉 Open this script and set GEMINI_API_KEY at the top.")
        sys.exit(1)

    # Ensure Raw_Assets directory exists
    os.makedirs(RAW_ASSETS_DIR, exist_ok=True)
    print(f"📂 Output directory: {RAW_ASSETS_DIR}\n")

    prompts = load_prompts()
    print(f"📋 Loaded {len(prompts)} image prompt(s) from {os.path.basename(PROMPTS_FILE)}\n")

    generated = 0
    failed = 0

    for item in prompts:
        name = item.get("name")
        prompt = item.get("prompt")

        if not name or not prompt:
            print(f"⚠️  Skipping entry with missing 'name' or 'prompt': {item}")
            continue

        print(f"🎨 Generating: {name}")
        print(f"   Prompt: {prompt[:80]}{'...' if len(prompt) > 80 else ''}")

        image_bytes = generate_image(name, prompt)
        if image_bytes is None:
            failed += 1
            continue

        try:
            path = save_image(name, image_bytes)
            print(f"   ✅ Saved: {os.path.basename(path)}")
            generated += 1
        except OSError as e:
            print(f"   ❌ Failed to save '{name}': {e}")
            failed += 1

    print(f"\n{'=' * 40}")
    print(f"✅ Generated: {generated}  |  ❌ Failed: {failed}")

    if generated > 0:
        run_resize_script()
    else:
        print("\n⚠️  No images were generated. Skipping resize step.")

    print("\n✅ Done.")


if __name__ == "__main__":
    main()