from fastapi import APIRouter, Depends, HTTPException, BackgroundTasks, UploadFile, File, Form
from fastapi.responses import JSONResponse, Response
from auth import get_current_active_user, User, supabase
import logging
import httpx
import os
from typing import Optional, Dict, Any
from pydantic import BaseModel
import base64
from uuid import uuid4
from services.hunyuan_service import _hunyuan_image_to_3d
import io
import numpy as np
from PIL import Image
import trimesh
import pyrender
from trimesh.transformations import translation_matrix, rotation_matrix

# Set PyOpenGL platform for headless rendering
os.environ.setdefault("PYOPENGL_PLATFORM", "egl")

def generate_thumbnail_from_bytes(mesh_data: bytes, size: int = 512) -> bytes:
    """
    Generate a thumbnail image from 3D mesh bytes data.
    
    Args:
        mesh_data: The 3D mesh file as bytes (GLB format)
        size: Output image size in pixels (default 512x512)
    
    Returns:
        PNG image data as bytes
    """
    try:
        # Load mesh from bytes
        mesh = trimesh.load(io.BytesIO(mesh_data), file_type="glb", force="mesh")
        
        # Get mesh dimensions before any transformations
        original_extents = mesh.extents
        longest_dimension = np.max(original_extents)
        
        # Scaling to normalize models to a target size
        target_size = 2.5
        scale_factor = target_size / longest_dimension if longest_dimension > 0 else 1.0
        
        # Calculate radius BEFORE scaling for consistent camera/lighting positioning
        bb = mesh.bounding_box_oriented.extents
        if not np.all(bb):
            bb = mesh.extents
        fixed_radius = np.linalg.norm(bb) * 0.6
        
        # Center the mesh
        mesh.apply_translation(-mesh.bounding_box.centroid)
        
        # Apply scaling transformation
        mesh.apply_scale(scale_factor)
        
        # Rotate for better viewing angle
        rotation = rotation_matrix(np.radians(30), [0.3, -0.5, 0])
        mesh.apply_transform(rotation)

        # Build scene
        tm_mesh = pyrender.Mesh.from_trimesh(mesh, smooth=False)
        scene = pyrender.Scene(bg_color=[0.15, 0.15, 0.15, 1])  # Gray background
        scene.add(tm_mesh)
        
        # Add lighting
        key_light = pyrender.PointLight(color=np.ones(3), intensity=40.0)
        fill_light = pyrender.PointLight(color=np.ones(3), intensity=20.0)
        back_light = pyrender.PointLight(color=np.ones(3), intensity=10.0)

        scene.add(key_light, pose=translation_matrix([fixed_radius, fixed_radius, fixed_radius]))
        scene.add(fill_light, pose=translation_matrix([-fixed_radius, fixed_radius, fixed_radius]))
        scene.add(back_light, pose=translation_matrix([0, -fixed_radius, -fixed_radius]))
        
        # Setup camera
        cam = pyrender.PerspectiveCamera(yfov=np.radians(45.0))
        cam_pose = translation_matrix([0, 0, fixed_radius * 2.5])
        scene.add(cam, pose=cam_pose)
        
        # Render thumbnail
        renderer = pyrender.OffscreenRenderer(viewport_width=size, viewport_height=size)
        try:
            color, _ = renderer.render(scene)
        finally:
            renderer.delete()
        
        # Convert to PIL Image and save as PNG bytes
        img = Image.fromarray(color)
        img_bytes = io.BytesIO()
        img.save(img_bytes, format='PNG')
        return img_bytes.getvalue()
        
    except Exception as e:
        logging.error(f"Failed to generate thumbnail: {str(e)}")
        raise

router = APIRouter(
    prefix="/user/models",
    tags=["User Models"]  # Removed global auth dependency; individual endpoints add it where needed
)

@router.get("/progress_update/{generated_model_id}", dependencies=[])
async def refresh_generated_model(generated_model_id: str):
    """
    Manual refresh endpoint.

    The front-end calls this route to fetch the latest status of a generation
    task and – if completed – persist the final Meshy response into Supabase.
    For text-to-3d with texture, this handles the two-step process (preview + refine).
    """
    try:
        # Handle placeholder IDs from frontend
        if generated_model_id.startswith("placeholder_"):
            raise HTTPException(status_code=400, detail="Invalid model ID. Model may not be ready yet or generation is still initializing.")
        
        # Validate that generated_model_id is a valid integer
        try:
            model_id_int = int(generated_model_id)
        except ValueError:
            raise HTTPException(status_code=400, detail="Invalid model ID format. Expected numeric ID.")
        
        # 1) Validate existence & retrieve the record (removed ownership check for public access).
        db_resp = supabase.from_("Generated_Models").select("*").eq("generated_model_id", model_id_int).limit(1).execute()  # .eq("user_id", current_user.id) - commented out for public access

        if not db_resp.data:
            raise HTTPException(status_code=404, detail="Model not found")

        generated_model = db_resp.data[0]
        prompts_config = generated_model.get("prompts_and_models_config", {})
        generation_type = prompts_config.get("generation_type")
        should_texture = prompts_config.get("should_texture", False)

        # Special handling for Hunyuan generation (doesn't use Meshy API)
        if generation_type == "hunyuan_image_to_3d":
            # For completed Hunyuan models, provide the view URL for 3D display
            model_urls = None
            thumbnail_url = None
            
            if generated_model.get("status") == "COMPLETED":
                model_urls = {
                    "glb": f"/user/models/{model_id_int}/view.glb"  # Relative URL to our view endpoint with extension
                }
                # Check if thumbnail exists
                thumbnail_check = supabase.from_("Model_Files").select("model_file_id").eq("generated_model_id", model_id_int).eq("is_preview_file", True).eq("file_format", "png").limit(1).execute()
                if thumbnail_check.data:
                    thumbnail_url = f"/user/models/{model_id_int}/thumbnail"
            
            return {
                "task_id": model_id_int,
                "status": generated_model.get("status", "IN_PROGRESS"),
                "progress": 100 if generated_model.get("status") == "COMPLETED" else 50,
                "model_urls": model_urls,
                "thumbnail_url": thumbnail_url,
                "texture_urls": None,
                "created_at": generated_model.get("created_at"),
                "started_at": generated_model.get("created_at"),
                "finished_at": generated_model.get("updated_at") if generated_model.get("status") == "COMPLETED" else None,
                "task_error": None,
                "database_updated": True,
                "generation_type": "hunyuan_image_to_3d",
                "message": "Hunyuan generation completed. 3D model ready for viewing." if generated_model.get("status") == "COMPLETED" else "Hunyuan generation in progress..."
            }

        meshy_task_id = generated_model.get("meshy_api_job_id")
        if not meshy_task_id:
            # Check if this model has files stored locally (similar to Hunyuan models) - removed ownership check for public access
            file_check = supabase.from_("Model_Files").select("model_file_id, file_name, file_format").eq("generated_model_id", model_id_int).limit(1).execute()  # .eq("user_id", current_user.id) - commented out for public access
            
            if file_check.data:
                # Model has local files - treat it like a Hunyuan model
                model_urls = None
                if generated_model.get("status") == "COMPLETED":
                    # Determine file format for URL
                    file_format = file_check.data[0].get("file_format", "glb").lower()
                    model_urls = {
                        file_format: f"/user/models/{model_id_int}/view.{file_format}"
                    }
                
                return {
                    "task_id": model_id_int,
                    "status": generated_model.get("status", "IN_PROGRESS"),
                    "progress": 100 if generated_model.get("status") == "COMPLETED" else 50,
                    "model_urls": model_urls,
                    "thumbnail_url": None,
                    "texture_urls": None,
                    "created_at": generated_model.get("created_at"),
                    "started_at": generated_model.get("created_at"),
                    "finished_at": generated_model.get("updated_at") if generated_model.get("status") == "COMPLETED" else None,
                    "task_error": None,
                    "database_updated": True,
                    "generation_type": generation_type,
                    "message": "Model completed. 3D model ready for viewing." if generated_model.get("status") == "COMPLETED" else "Model generation in progress..."
                }
            else:
                # No local files and no Meshy task ID - this model might be incomplete or from old system
                raise HTTPException(status_code=400, detail="Model has no associated files or Meshy task ID. This model may be incomplete or from an older system.")

        # 2) Query Meshy API for the latest status.
        meshy_api_key = os.getenv("MESHY_API_KEY")
        if not meshy_api_key:
            raise HTTPException(status_code=500, detail="MESHY_API_KEY not configured")

        async with httpx.AsyncClient(timeout=30.0) as client:
            headers = {"Authorization": f"Bearer {meshy_api_key}"}

            # Special handling for text-to-3d with texture (two-step process)
            if generation_type == "text_to_3d" and should_texture:
                return await _handle_text_to_3d_with_texture(
                    model_id_int, generated_model, prompts_config, 
                    meshy_task_id, meshy_api_key, client, headers
                )

            # Standard handling for other generation types
            # Determine which Meshy progress endpoint to query based on generation type
            if generation_type == "image_to_3d":
                meshy_progress_url = f"https://api.meshy.ai/openapi/v1/image-to-3d/{meshy_task_id}"
            elif generation_type == "multi_image_to_3d":
                meshy_progress_url = f"https://api.meshy.ai/openapi/v1/multi-image-to-3d/{meshy_task_id}"
            else:
                # Default to text-to-3d (without texture)
                meshy_progress_url = f"https://api.meshy.ai/openapi/v2/text-to-3d/{meshy_task_id}"

            response = await client.get(
                meshy_progress_url,
                headers=headers,
            )
            
            if response.status_code != 200:
                raise HTTPException(
                    status_code=response.status_code, 
                    detail=f"Failed to get task progress from Meshy AI: {response.text}"
                )
            
            meshy_response = response.json()
            
            # If the task has succeeded, update the database
            if meshy_response.get("status") == "SUCCEEDED":
                # Update the Generated_Models record with the completed task information
                update_data = {
                    "status": "COMPLETED",
                    "updated_at": "now()",
                    # Store the complete response in the prompts_and_models_config field
                    "prompts_and_models_config": meshy_response
                }
                
                supabase.from_("Generated_Models").update(update_data).eq("generated_model_id", generated_model["generated_model_id"]).execute()
                
                logging.info(f"Updated generated model {generated_model['generated_model_id']} with completion data")
            
            # Return the progress information along with update status
            return {
                "task_id": model_id_int,
                "status": meshy_response.get("status"),
                "progress": meshy_response.get("progress"),
                "model_urls": meshy_response.get("model_urls"),
                "thumbnail_url": meshy_response.get("thumbnail_url"),
                "texture_urls": meshy_response.get("texture_urls"),
                "created_at": meshy_response.get("created_at"),
                "started_at": meshy_response.get("started_at"),
                "finished_at": meshy_response.get("finished_at"),
                "task_error": meshy_response.get("task_error"),
                "database_updated": meshy_response.get("status") == "SUCCEEDED"
            }
            
    except HTTPException:
        # Re-raise HTTP exceptions as-is
        raise
    except Exception as e:
        logging.error(f"Error in refresh_generated_model: {str(e)}")
        raise HTTPException(status_code=500, detail=f"Internal server error: {str(e)}")


async def _handle_text_to_3d_with_texture(
    generated_model_id: int,
    generated_model: Dict[str, Any],
    prompts_config: Dict[str, Any],
    preview_task_id: str,
    meshy_api_key: str,
    client: httpx.AsyncClient,
    headers: Dict[str, str]
):
    """Handle the two-step text-to-3d with texture process (preview + refine)"""
    
    refine_task_id = prompts_config.get("refine_task_id")
    stage = prompts_config.get("stage", "generating_preview")
    
    # Helper to build consistent response
    def _build_response(status: str, progress_val: float, extra: Dict[str, Any] = None):
        base = {
            "task_id": generated_model_id,
            "status": status,
            "progress": progress_val,
            "database_updated": False,
        }
        if extra:
            base.update(extra)
        return base
    
    # Case 1: Preview task still in progress or just completed
    if not refine_task_id:
        # Check preview task status
        preview_url = f"https://api.meshy.ai/openapi/v2/text-to-3d/{preview_task_id}"
        preview_resp = await client.get(preview_url, headers=headers)
        
        if preview_resp.status_code != 200:
            raise HTTPException(
                status_code=preview_resp.status_code,
                detail=f"Failed to get preview task progress: {preview_resp.text}"
            )
        
        preview_data = preview_resp.json()
        
        # Preview still in progress
        if preview_data.get("status") != "SUCCEEDED":
            # Progress is 0-50% for preview phase
            preview_progress = preview_data.get("progress", 0)
            adjusted_progress = preview_progress / 2
            return _build_response(
                preview_data.get("status", "IN_PROGRESS"), 
                adjusted_progress,
                {
                    "model_urls": preview_data.get("model_urls"),
                    "thumbnail_url": preview_data.get("thumbnail_url"),
                    "created_at": preview_data.get("created_at"),
                    "started_at": preview_data.get("started_at"),
                }
            )
        
        # Preview completed - launch refine task
        refine_payload = {
            "mode": "refine",
            "preview_task_id": preview_task_id,
            "texture_prompt": prompts_config.get("reframed_prompt", prompts_config.get("original_prompt", "")),
            "ai_model": "meshy-4"
        }
        
        refine_resp = await client.post(
            "https://api.meshy.ai/openapi/v2/text-to-3d",
            headers=headers,
            json=refine_payload
        )
        
        if refine_resp.status_code not in (200, 201, 202):
            raise HTTPException(
                status_code=refine_resp.status_code,
                detail=f"Failed to create refine task: {refine_resp.text}"
            )
        
        refine_data = refine_resp.json()
        new_refine_id = refine_data.get("result") or refine_data.get("id") or refine_data.get("task_id")
        
        if not new_refine_id:
            raise HTTPException(status_code=500, detail="No refine task ID received from Meshy API")
        
        # Update database with refine task info
        updated_config = {
            **prompts_config,
            "refine_task_id": new_refine_id,
            "stage": "refining"
        }
        
        supabase.from_("Generated_Models").update({
            "prompts_and_models_config": updated_config
        }).eq("generated_model_id", generated_model_id).execute()
        
        return _build_response(
            "REFINING",
            50,  # 50% - preview done, refine started
            {
                "database_updated": True,
                "model_urls": preview_data.get("model_urls"),
                "thumbnail_url": preview_data.get("thumbnail_url"),
            }
        )
    
    # Case 2: Refine task in progress or completed
    refine_url = f"https://api.meshy.ai/openapi/v2/text-to-3d/{refine_task_id}"
    refine_resp = await client.get(refine_url, headers=headers)
    
    if refine_resp.status_code != 200:
        raise HTTPException(
            status_code=refine_resp.status_code,
            detail=f"Failed to get refine task progress: {refine_resp.text}"
        )
    
    refine_data = refine_resp.json()
    
    # Refine completed
    if refine_data.get("status") == "SUCCEEDED":
        # Update database as completed - overwrite config with refine response
        supabase.from_("Generated_Models").update({
            "status": "COMPLETED",
            "updated_at": "now()",
            "prompts_and_models_config": refine_data
        }).eq("generated_model_id", generated_model_id).execute()
        
        # Return the complete refine data with additional metadata
        return {
            "task_id": generated_model_id,
            "database_updated": True,
            **refine_data
        }
    
    # Refine still in progress
    refine_progress = refine_data.get("progress", 0)
    # Progress is 50-100% for refine phase
    adjusted_progress = 50 + (refine_progress / 2)
    
    return _build_response(
        refine_data.get("status", "REFINING"),
        adjusted_progress,
        {
            "model_urls": None,
            "thumbnail_url": None,
            "texture_urls": None,
            "created_at": refine_data.get("created_at"),
            "started_at": refine_data.get("started_at"),
        }
    )

class TextPrompt(BaseModel):
    text: str
    # When true, a secondary *refine* task will be run to add texture to the model.
    should_texture: Optional[bool] = False

# NEW: Request model for Image to 3D generation
class ImageTo3DRequest(BaseModel):
    image_url: str
    # Optional Meshy parameters (all directly forwarded if provided)
    ai_model: Optional[str] = None
    topology: Optional[str] = None
    target_polycount: Optional[int] = None
    symmetry_mode: Optional[str] = None
    should_remesh: Optional[bool] = True
    should_texture: Optional[bool] = True
    enable_pbr: Optional[bool] = False
    texture_prompt: Optional[str] = None
    texture_image_url: Optional[str] = None
    moderation: Optional[bool] = None

# Helper to check & decrement credits using Supabase
async def _check_and_decrement_credits(user_id: str, cost: int = 1):
    """Validate that the user has at least *cost* credits available and deduct them.

    Args:
        user_id: The Supabase user identifier.
        cost:  How many credits the generation should consume (default = 1).
    """
    if cost < 1:
        # Defensive – we never expect non-positive costs
        cost = 1

    credit = (
        supabase.from_("User_Credit_Account")
        .select("num_of_available_gens")
        .eq("user_id", user_id)
        .single()
        .execute()
    )

    if not credit.data:
        raise HTTPException(status_code=403, detail="No credit account found. Please complete your profile.")

    available = credit.data["num_of_available_gens"]

    if available is None or available < cost:
        raise HTTPException(status_code=402, detail="No credits left. Please purchase more to generate models.")

    new_credits = available - cost

    supabase.from_("User_Credit_Account").update({"num_of_available_gens": new_credits}).eq("user_id", user_id).execute()

# Background task for text-to-3d processing
async def _process_text_to_3d_background(
    generated_model_id: int,
    user_id: str,
    original_prompt: str,
    should_texture: bool = False,
):
    """Background task to handle OpenAI reframing and Meshy API call for text-to-3d"""
    try:
        # 1. Reframe prompt via OpenAI
        reframed_prompt = original_prompt  # Default fallback
        
        openai_key = os.getenv("OPENAI_API_KEY")
        if openai_key:
            try:
                async with httpx.AsyncClient(timeout=30.0) as client:
                    oai_resp = await client.post(
                        "https://api.openai.com/v1/chat/completions",
                        headers={"Authorization": f"Bearer {openai_key}"},
                        json={
                            "model": "gpt-4o-mini",
                            "messages": [
                                {"role": "system", "content": "REPLY ONLY WITH NEW PROMPT, no other text. IF USER PROMPT CONTAINS HARMFUL CONTENT, CHANGE IT TO SOMETHING SAFE and somewhat related. Rephrase the user description to simple and short."},
                                {"role": "user", "content": original_prompt},
                            ],
                        },
                    )
                    if oai_resp.status_code == 200:
                        reframed_prompt = oai_resp.json()["choices"][0]["message"]["content"]
            except Exception as ex:
                logging.warning(f"OpenAI reframing failed, using original prompt: {ex}")

        # 2. Update DB with reframed prompt
        try:
            supabase.from_("Generated_Models").update({
                "prompts_and_models_config": {
                    "generation_type": "text_to_3d",
                    "original_prompt": original_prompt,
                    "reframed_prompt": reframed_prompt,
                    "should_texture": should_texture,
                    "status": "processing",
                    "stage": "creating_3d_model",
                },
            }).eq("generated_model_id", generated_model_id).execute()
        except Exception as ex:
            logging.warning(f"Failed to update DB with reframed prompt: {ex}")

        # 3. Send request to Meshy
        meshy_key = os.getenv("MESHY_API_KEY")
        if not meshy_key:
            logging.error("MESHY_API_KEY not configured")
            return

        meshy_payload = {
            "mode": "preview",
            "prompt": reframed_prompt,
            "ai_model": "meshy-5",
        }

        async with httpx.AsyncClient(timeout=30.0) as client:
            meshy_resp = await client.post(
                "https://api.meshy.ai/openapi/v2/text-to-3d",
                headers={"Authorization": f"Bearer {meshy_key}"},
                json=meshy_payload,
            )

        if meshy_resp.status_code not in (200, 201, 202):
            logging.error(f"Meshy API failed: {meshy_resp.status_code} - {meshy_resp.text}")
            return

        meshy_data = meshy_resp.json()
        meshy_task_id = meshy_data.get("result") or meshy_data.get("id") or meshy_data.get("task_id")

        if not meshy_task_id:
            logging.error("No task ID received from Meshy API")
            return

        # 4. Finalize DB record
        try:
            supabase.from_("Generated_Models").update({
                "meshy_api_job_id": meshy_task_id,
                "prompts_and_models_config": {
                    "generation_type": "text_to_3d",
                    "original_prompt": original_prompt,
                    "reframed_prompt": reframed_prompt,
                    "should_texture": should_texture,
                    "status": "processing",
                    "stage": "generating_preview" if should_texture else "generating",
                    "meshy_response": meshy_data,
                },
            }).eq("generated_model_id", generated_model_id).execute()
            logging.info(f"Successfully started text-to-3d generation for model {generated_model_id}")
        except Exception as ex:
            logging.error(f"Failed to update DB with Meshy taskId: {ex}")

    except Exception as ex:
        logging.error(f"Background processing failed for text-to-3d model {generated_model_id}: {ex}")

# CREDITS ARE NOT DECREMENTED HERE / DECREMENT BEFORE CALLING THIS FUNCTION
async def _process_hunyuan_image_to_3d_background(generated_model_id: int, image_url: str, user_id: str):
    """Background task to handle Hunyuan API call for image-to-3d"""
    try:
        hunyuan_response = _hunyuan_image_to_3d(image_url)

        if not hunyuan_response:
            logging.error(f"Hunyuan API failed for model {generated_model_id}")
            return

        # Extract mesh URL from response
        mesh_url = hunyuan_response.get("output", {}).get("mesh") if "output" in hunyuan_response else hunyuan_response.get("mesh")
        
        if not mesh_url:
            logging.error(f"No mesh URL found in Hunyuan response for model {generated_model_id}")
            return

        # Download the mesh file
        async with httpx.AsyncClient(timeout=60.0) as client:
            mesh_response = await client.get(mesh_url)
            
            if mesh_response.status_code != 200:
                logging.error(f"Failed to download mesh file from {mesh_url}: {mesh_response.status_code}")
                return
            
            mesh_data = mesh_response.content
            
        # Determine file format from URL or default to .glb
        file_name = mesh_url.split("/")[-1] if "/" in mesh_url else f"hunyuan_model_{generated_model_id}.glb"
        if "." not in file_name:
            file_name += ".glb"
        
        file_format = file_name.split(".")[-1].lower()
        file_size = len(mesh_data)

        # Generate thumbnail from the mesh data
        thumbnail_data = None
        try:
            thumbnail_data = generate_thumbnail_from_bytes(mesh_data, size=512)
            logging.info(f"Successfully generated thumbnail for model {generated_model_id}")
        except Exception as ex:
            logging.error(f"Failed to generate thumbnail for model {generated_model_id}: {ex}")

        # Update DB record with Hunyuan response
        supabase.from_("Generated_Models").update({
            "status": "COMPLETED",
            "updated_at": "now()",
            "prompts_and_models_config": hunyuan_response,
        }).eq("generated_model_id", generated_model_id).execute()

        # Convert binary data to Postgres bytea hex format ("\\x" prefix) for safe insertion
        encoded_hex_data = "\\x" + mesh_data.hex()

        # Insert the mesh file into Model_Files table
        supabase.from_("Model_Files").insert({
            "user_id": user_id,
            "generated_model_id": generated_model_id,
            "model_data": encoded_hex_data,  # stored as hex string compatible with bytea
            "file_name": file_name,
            "file_format": file_format,
            "file_size": file_size,
            "metadata": f"Hunyuan3D generated mesh file. Original URL: {mesh_url}",
            "is_preview_file": False,
        }).execute()

        # Insert the thumbnail if generation was successful
        if thumbnail_data:
            try:
                # Convert thumbnail bytes to hex format for Postgres bytea
                thumbnail_hex_data = "\\x" + thumbnail_data.hex()
                thumbnail_file_name = f"thumbnail_{generated_model_id}.png"
                
                supabase.from_("Model_Files").insert({
                    "user_id": user_id,
                    "generated_model_id": generated_model_id,
                    "model_data": thumbnail_hex_data,
                    "file_name": thumbnail_file_name,
                    "file_format": "png",
                    "file_size": len(thumbnail_data),
                    "metadata": "Generated thumbnail image for 3D model preview",
                    "is_preview_file": True,  # Flag to indicate this is a thumbnail/preview
                }).execute()
                
                logging.info(f"Successfully stored thumbnail for model {generated_model_id}")
            except Exception as ex:
                logging.error(f"Failed to store thumbnail for model {generated_model_id}: {ex}")

        logging.info(f"Successfully completed Hunyuan image-to-3d generation for model {generated_model_id}")
        
    except Exception as ex:
        logging.error(f"Background processing failed for Hunyuan image-to-3d model {generated_model_id}: {ex}")

# Background task for image-to-3d processing
async def _process_image_to_3d_background(generated_model_id: int, payload: Dict[str, Any], generation_type: str):
    """Background task to handle Meshy API call for image-to-3d"""
    try:
        # Send request to Meshy
        meshy_key = os.getenv("MESHY_API_KEY")
        if not meshy_key:
            logging.error("MESHY_API_KEY not configured")
            return

        # Determine the correct Meshy endpoint
        if generation_type == "multi_image_to_3d":
            meshy_endpoint = "https://api.meshy.ai/openapi/v1/multi-image-to-3d"
        else:
            meshy_endpoint = "https://api.meshy.ai/openapi/v1/image-to-3d"

        async with httpx.AsyncClient(timeout=30.0) as client:
            meshy_resp = await client.post(
                meshy_endpoint,
                headers={"Authorization": f"Bearer {meshy_key}"},
                json=payload,
            )

        if meshy_resp.status_code not in (200, 201, 202):
            logging.error(f"Meshy API failed: {meshy_resp.status_code} - {meshy_resp.text}")
            return

        meshy_data = meshy_resp.json()
        meshy_task_id = meshy_data.get("result") or meshy_data.get("id") or meshy_data.get("task_id")

        if not meshy_task_id:
            logging.error("No task ID received from Meshy API")
            return

        # Update DB record with Meshy task ID
        try:
            # Get current config to preserve it
            current_record = supabase.from_("Generated_Models").select("prompts_and_models_config").eq("generated_model_id", generated_model_id).single().execute()
            current_config = current_record.data.get("prompts_and_models_config", {}) if current_record.data else {}
            
            # Update config with Meshy response
            updated_config = {**current_config}
            updated_config.update({
                "status": "processing",
                "stage": "generating",
                "meshy_response": meshy_data,
            })

            supabase.from_("Generated_Models").update({
                "meshy_api_job_id": meshy_task_id,
                "prompts_and_models_config": updated_config,
            }).eq("generated_model_id", generated_model_id).execute()
            
            logging.info(f"Successfully started {generation_type} generation for model {generated_model_id}")
        except Exception as ex:
            logging.error(f"Failed to update DB with Meshy taskId: {ex}")

    except Exception as ex:
        logging.error(f"Background processing failed for {generation_type} model {generated_model_id}: {ex}")

@router.post("/text-to-3d")
async def text_to_3d(prompt: TextPrompt, background_tasks: BackgroundTasks, current_user: User = Depends(get_current_active_user)):
    """
    Create a Meshy Text-to-3D generation job.

    Returns immediately after creating the database record. All processing 
    (OpenAI reframing, Meshy API call) happens in the background.
    """

    # Determine credit cost (texture generation costs 3 credits)
    should_texture_flag = getattr(prompt, "should_texture", False)
    credit_cost = 3 if should_texture_flag else 1

    # Credit check and decrement
    await _check_and_decrement_credits(current_user.id, credit_cost)

    # Insert initial DB record and return immediately
    try:
        insert_res = supabase.from_("Generated_Models").insert({
            "status": "IN_PROGRESS",
            "user_id": current_user.id,
            "meshy_api_job_id": None,
            "model_name": f"{prompt.text[:50]}{'...' if len(prompt.text) > 50 else ''}",
            "prompts_and_models_config": {
                "generation_type": "text_to_3d",
                "original_prompt": prompt.text,
                "should_texture": should_texture_flag,
                "status": "initializing",
                "stage": "reframing_prompt",
            },
        }).execute()
        generated_model_id = insert_res.data[0]["generated_model_id"] if insert_res.data else None
        
        if not generated_model_id:
            raise HTTPException(status_code=500, detail="Failed to create model record")
        
        # Add background task for processing
        background_tasks.add_task(
            _process_text_to_3d_background,
            generated_model_id,
            current_user.id,
            prompt.text,
            should_texture_flag,
        )
        
        # Return immediately with explicit headers
        response_data = {
            "generated_model_id": generated_model_id,
            "status": "initializing",
            "original_prompt": prompt.text,
            "message": "Generation started. Use the progress_update endpoint to check status."
        }
        
        logging.info(f"Returning response for text-to-3d: {response_data}")
        
        response = JSONResponse(content=response_data, status_code=200)
        # Allowed header; avoids disallowed connection-specific headers under HTTP/2
        response.headers["Cache-Control"] = "no-cache"
        return response
        
    except Exception as ex:
        logging.error(f"Failed to create initial model DB record: {ex}")
        raise HTTPException(status_code=500, detail=f"Failed to start generation: {ex}")

@router.post("/image-to-3d")
async def image_to_3d(
    background_tasks: BackgroundTasks,
    image: UploadFile = File(None),
    image_url: Optional[str] = Form(None),
    current_user: User = Depends(get_current_active_user),
):
    """
    Create a Hunyuan3D Image-to-3D generation job.

    The client can either:
    1. Upload an image file (multipart/form-data) via the "image" field
    2. Provide an already publicly accessible URL via the "image_url" form field

    If a file is uploaded we first store it in Supabase Storage and use the
    resulting public URL when triggering the Hunyuan job.
    """

    # Validate input – at least one source must be provided
    if image is None and not image_url:
        raise HTTPException(status_code=400, detail="Either an image file or image_url must be provided")

    # If we received an image file, upload it to Supabase Storage to obtain a public URL
    if image is not None:
        content = await image.read()
        if not content:
            raise HTTPException(status_code=400, detail="Uploaded image is empty")

        file_ext = os.path.splitext(image.filename)[1] or ".jpg"
        unique_name = f"{uuid4().hex}{file_ext}"
        # Determine bucket name (hard-coded to avoid missing env vars)
        bucket_name = "hunyuan-inputs"  # storage bucket for Hunyuan inputs

        try:
            # Upload bytes to Supabase Storage
            upload_resp = supabase.storage.from_(bucket_name).upload(
                unique_name,
                content,
                {"content-type": image.content_type or "application/octet-stream"},
            )

            # Handle both supabase-py <2.0 (dict response) and >=2.0 (UploadResponse object)
            upload_error = None
            if isinstance(upload_resp, dict):
                upload_error = upload_resp.get("error")
            elif hasattr(upload_resp, "error"):
                upload_error = upload_resp.error

            if upload_error:
                # Ensure we always raise a string for logging / HTTPException
                raise RuntimeError(str(upload_error))

            public_url_resp = supabase.storage.from_(bucket_name).get_public_url(unique_name)

            # Similar compatibility handling for get_public_url()
            if isinstance(public_url_resp, str):
                image_url = public_url_resp
            elif isinstance(public_url_resp, dict):
                image_url = public_url_resp.get("publicURL") or public_url_resp.get("publicUrl")
            elif hasattr(public_url_resp, "data") and isinstance(public_url_resp.data, dict):
                image_url = public_url_resp.data.get("publicURL") or public_url_resp.data.get("publicUrl")
            else:
                image_url = None
            if not image_url:
                raise RuntimeError("Failed to retrieve public URL for uploaded image")
        except Exception as ex:
            logging.error(f"Failed to upload image to Supabase storage: {ex}")
            raise HTTPException(status_code=500, detail="Failed to upload image to storage")

    # At this point, image_url should be a publicly accessible URL
    if not image_url:
        raise HTTPException(status_code=400, detail="Could not determine image URL")

    # Credit check and decrement - Hunyuan generation costs 2 credits
    await _check_and_decrement_credits(current_user.id, 2)

    source_name = image.filename if image is not None else (image_url.split('/')[-1] if '/' in image_url else 'image')

    # Insert initial DB record and return immediately
    try:
        insert_res = supabase.from_("Generated_Models").insert({
            "status": "IN_PROGRESS",
            "user_id": current_user.id,
            "meshy_api_job_id": None,
            "model_name": f"Hunyuan 3D from {source_name}",
            "prompts_and_models_config": {
                "generation_type": "hunyuan_image_to_3d",
                "input_image_url": image_url,
                "status": "initializing",
                "stage": "processing_image",
            },
        }).execute()
        generated_model_id = insert_res.data[0]["generated_model_id"] if insert_res.data else None

        if not generated_model_id:
            raise HTTPException(status_code=500, detail="Failed to create model record")

        # Add background task for Hunyuan processing
        background_tasks.add_task(
            _process_hunyuan_image_to_3d_background,
            generated_model_id,
            image_url,
            current_user.id,
        )

        response_data = {
            "generated_model_id": generated_model_id,
            "status": "initializing",
            "input_image_url": image_url,
            "message": "Hunyuan 3D generation started. Use the progress_update endpoint to check status.",
        }

        logging.info(f"Returning response for hunyuan image-to-3d: {response_data}")

        response = JSONResponse(content=response_data, status_code=200)
        response.headers["Cache-Control"] = "no-cache"
        return response

    except Exception as ex:
        logging.error(f"Failed to create initial model DB record: {ex}")
        raise HTTPException(status_code=500, detail=f"Failed to start generation: {ex}")

@router.get("/{generated_model_id}/file")
async def get_model_file(
    generated_model_id: str
):
    """
    Get the model file info for a generated model belonging to the current user.
    """
    try:
        # Handle placeholder IDs and validate integer format
        if generated_model_id.startswith("placeholder_"):
            raise HTTPException(status_code=400, detail="Invalid model ID. Model may not be ready yet or generation is still initializing.")
        
        try:
            model_id_int = int(generated_model_id)
        except ValueError:
            raise HTTPException(status_code=400, detail="Invalid model ID format. Expected numeric ID.")
        
        # First check if the model exists (removed user ownership check for public access)
        model_check = supabase.from_("Generated_Models").select("generated_model_id, user_id, model_name").eq("generated_model_id", model_id_int).limit(1).execute()  # .eq("user_id", current_user.id) - commented out for public access
        
        if not model_check.data:
            raise HTTPException(status_code=404, detail="Model not found.")
        
        # Get the single model file for this generated model (removed ownership verification for public access)
        file_result = supabase.from_("Model_Files").select("model_file_id, file_name, file_format, file_size, metadata, is_preview_file, created_at").eq("generated_model_id", model_id_int).limit(1).execute()  # .eq("user_id", current_user.id) - commented out for public access
        
        if not file_result.data:
            raise HTTPException(status_code=404, detail="No model file found for this generated model.")
        
        return {
            "generated_model_id": generated_model_id,
            "model_name": model_check.data[0].get("model_name"),
            "file": file_result.data[0]
        }
        
    except HTTPException:
        # Re-raise HTTP exceptions as-is
        raise
    except Exception as e:
        logging.error(f"Failed to get model file for {generated_model_id}: {str(e)}")
        raise HTTPException(status_code=500, detail=f"Internal server error: {str(e)}")

@router.get("/{generated_model_id}/download")
async def download_model_file(
    generated_model_id: str
):
    """
    Download the model file for a generated model.
    """
    try:
        # Handle placeholder IDs and validate integer format
        if generated_model_id.startswith("placeholder_"):
            raise HTTPException(status_code=400, detail="Invalid model ID. Model may not be ready yet or generation is still initializing.")
        
        try:
            model_id_int = int(generated_model_id)
        except ValueError:
            raise HTTPException(status_code=400, detail="Invalid model ID format. Expected numeric ID.")
        
        # First check if the model exists (removed user ownership check for public access)
        model_check = supabase.from_("Generated_Models").select("generated_model_id, user_id, model_name").eq("generated_model_id", model_id_int).limit(1).execute()  # .eq("user_id", current_user.id) - commented out for public access
        
        if not model_check.data:
            raise HTTPException(status_code=404, detail="Model not found.")
        
        # Get the model file (removed ownership verification for public access)
        file_result = supabase.from_("Model_Files").select("*").eq("generated_model_id", model_id_int).limit(1).execute()  # .eq("user_id", current_user.id) - commented out for public access
        
        if not file_result.data:
            raise HTTPException(status_code=404, detail="No model file found for this generated model.")
        
        file_data = file_result.data[0]

        # Supabase stores bytea as base64-encoded strings; decode before sending.
        raw_data = file_data.get("model_data")
        if isinstance(raw_data, str):
            try:
                # Attempt base64 decode
                raw_data = base64.b64decode(raw_data)
            except Exception:
                # Fallback for hex format ("\\x" prefix)
                if raw_data.startswith("\\x"):
                    raw_data = bytes.fromhex(raw_data[2:])

        if raw_data is None:
            raise HTTPException(status_code=500, detail="Failed to decode model file data.")

        return Response(
            content=raw_data,
            media_type="application/octet-stream",
            headers={
                "Content-Disposition": f"attachment; filename={file_data['file_name']}"
            }
        )
        
    except HTTPException:
        # Re-raise HTTP exceptions as-is
        raise
    except Exception as e:
        logging.error(f"Failed to download model file for {generated_model_id}: {str(e)}")
        raise HTTPException(status_code=500, detail=f"Internal server error: {str(e)}")

@router.get("/{generated_model_id}/view")
async def view_model_file(
    generated_model_id: str
):
    """
    Serve the 3D model file inline for frontend 3D viewers.
    This endpoint serves the file with appropriate headers for direct consumption by 3D libraries.
    """
    try:
        # Handle placeholder IDs and validate integer format
        if generated_model_id.startswith("placeholder_"):
            logging.warning(f"Placeholder ID received: {generated_model_id}")
            raise HTTPException(status_code=400, detail="Invalid model ID. Model may not be ready yet or generation is still initializing.")
        
        try:
            model_id_int = int(generated_model_id)
        except ValueError:
            logging.error(f"Invalid model ID format: {generated_model_id}")
            raise HTTPException(status_code=400, detail="Invalid model ID format. Expected numeric ID.")
        
        logging.info(f"Looking up model {model_id_int} for view endpoint")
        
        # First check if the model exists (removed user ownership check for public access)
        model_check = supabase.from_("Generated_Models").select("generated_model_id, user_id, model_name, status").eq("generated_model_id", model_id_int).limit(1).execute()  # .eq("user_id", current_user.id) - commented out for public access
        
        if not model_check.data:
            logging.error(f"Model {model_id_int} not found in Generated_Models table")
            raise HTTPException(status_code=404, detail="Model not found.")
        
        logging.info(f"Found model {model_id_int}: {model_check.data[0]}")
        
        # Get the model file (removed ownership verification for public access)
        file_result = supabase.from_("Model_Files").select("*").eq("generated_model_id", model_id_int).limit(1).execute()  # .eq("user_id", current_user.id) - commented out for public access
        
        if not file_result.data:
            logging.error(f"No model file found for model {model_id_int} in Model_Files table")
            raise HTTPException(status_code=404, detail="No model file found for this generated model.")
        
        file_data = file_result.data[0]

        # Supabase stores bytea as base64-encoded strings; decode before sending.
        raw_data = file_data.get("model_data")
        if isinstance(raw_data, str):
            try:
                # Attempt base64 decode
                raw_data = base64.b64decode(raw_data)
            except Exception:
                # Fallback for hex format ("\\x" prefix)
                if raw_data.startswith("\\x"):
                    raw_data = bytes.fromhex(raw_data[2:])

        if raw_data is None:
            raise HTTPException(status_code=500, detail="Failed to decode model file data.")

        # Determine appropriate MIME type based on file format
        file_format = file_data.get("file_format", "").lower()
        content_type = "application/octet-stream"  # Default fallback
        
        if file_format == "glb":
            content_type = "model/gltf-binary"
        elif file_format == "gltf":
            content_type = "model/gltf+json"
        elif file_format == "obj":
            content_type = "text/plain"  # OBJ files are text-based
        elif file_format == "stl":
            content_type = "model/stl"
        elif file_format == "fbx":
            content_type = "application/octet-stream"
        
        return Response(
            content=raw_data,
            media_type=content_type,
            headers={
                "Access-Control-Allow-Origin": "*",
                "Access-Control-Allow-Methods": "GET, HEAD, OPTIONS",
                "Access-Control-Allow-Headers": "Authorization, Content-Type",
                "Cache-Control": "public, max-age=3600"  # Cache for 1 hour
            }
        )
        
    except HTTPException:
        # Re-raise HTTP exceptions as-is
        raise
    except Exception as e:
        logging.error(f"Failed to serve model file for {generated_model_id}: {str(e)}")
        raise HTTPException(status_code=500, detail=f"Internal server error: {str(e)}")

# Allow URLs like /user/models/{id}/view.glb or .gltf etc.
@router.get("/{generated_model_id}/view.{file_ext}")
async def view_model_file_with_ext(generated_model_id: str, file_ext: str):
    """Proxy to view_model_file to serve model regardless of extension in URL."""
    return await view_model_file(generated_model_id)

@router.get("/{generated_model_id}/thumbnail")
async def get_model_thumbnail(generated_model_id: str):
    """
    Serve the thumbnail image for a generated model.
    Returns a PNG image that can be displayed in the frontend for model previews.
    """
    try:
        # Handle placeholder IDs and validate integer format
        if generated_model_id.startswith("placeholder_"):
            raise HTTPException(status_code=400, detail="Invalid model ID. Model may not be ready yet or generation is still initializing.")
        
        try:
            model_id_int = int(generated_model_id)
        except ValueError:
            raise HTTPException(status_code=400, detail="Invalid model ID format. Expected numeric ID.")
        
        # First check if the model exists (removed user ownership check for public access)
        model_check = supabase.from_("Generated_Models").select("generated_model_id, user_id, model_name").eq("generated_model_id", model_id_int).limit(1).execute()
        
        if not model_check.data:
            raise HTTPException(status_code=404, detail="Model not found.")
        
        # Get the thumbnail file (removed ownership verification for public access)
        thumbnail_result = supabase.from_("Model_Files").select("*").eq("generated_model_id", model_id_int).eq("is_preview_file", True).eq("file_format", "png").limit(1).execute()
        
        if not thumbnail_result.data:
            raise HTTPException(status_code=404, detail="No thumbnail found for this model.")
        
        thumbnail_data = thumbnail_result.data[0]

        # Decode the thumbnail data
        raw_data = thumbnail_data.get("model_data")
        if isinstance(raw_data, str):
            try:
                # Attempt base64 decode
                raw_data = base64.b64decode(raw_data)
            except Exception:
                # Fallback for hex format ("\\x" prefix)
                if raw_data.startswith("\\x"):
                    raw_data = bytes.fromhex(raw_data[2:])

        if raw_data is None:
            raise HTTPException(status_code=500, detail="Failed to decode thumbnail data.")

        return Response(
            content=raw_data,
            media_type="image/png",
            headers={
                "Access-Control-Allow-Origin": "*",
                "Access-Control-Allow-Methods": "GET, HEAD, OPTIONS",
                "Access-Control-Allow-Headers": "Authorization, Content-Type",
                "Cache-Control": "public, max-age=3600"  # Cache for 1 hour
            }
        )
        
    except HTTPException:
        # Re-raise HTTP exceptions as-is
        raise
    except Exception as e:
        logging.error(f"Failed to serve thumbnail for {generated_model_id}: {str(e)}")
        raise HTTPException(status_code=500, detail=f"Internal server error: {str(e)}")

@router.get("/{generated_model_id}/debug")
async def debug_model(generated_model_id: str):
    """
    Debug endpoint to check model and file existence in production.
    Returns detailed information about what's in the database.
    """
    try:
        # Handle placeholder IDs and validate integer format
        if generated_model_id.startswith("placeholder_"):
            return {"error": "Placeholder ID", "generated_model_id": generated_model_id}
        
        try:
            model_id_int = int(generated_model_id)
        except ValueError:
            return {"error": "Invalid ID format", "generated_model_id": generated_model_id}
        
        # Check if model exists
        model_check = supabase.from_("Generated_Models").select("*").eq("generated_model_id", model_id_int).execute()
        
        # Check for files
        files_check = supabase.from_("Model_Files").select("*").eq("generated_model_id", model_id_int).execute()
        
        return {
            "generated_model_id": model_id_int,
            "model_exists": bool(model_check.data),
            "model_data": model_check.data[0] if model_check.data else None,
            "files_exist": bool(files_check.data),
            "files_count": len(files_check.data) if files_check.data else 0,
            "files_data": files_check.data if files_check.data else []
        }
        
    except Exception as e:
        return {
            "error": f"Debug error: {str(e)}",
            "generated_model_id": generated_model_id
        }

@router.delete("/{generated_model_id}", dependencies=[Depends(get_current_active_user)])
async def delete_model(
    generated_model_id: str,
    current_user: User = Depends(get_current_active_user)
):
    """
    Delete a generated model and its associated files for the current user.
    """
    try:
        # Handle placeholder IDs and validate integer format
        if generated_model_id.startswith("placeholder_"):
            raise HTTPException(status_code=400, detail="Invalid model ID. Model may not be ready yet or generation is still initializing.")
        
        try:
            model_id_int = int(generated_model_id)
        except ValueError:
            raise HTTPException(status_code=400, detail="Invalid model ID format. Expected numeric ID.")
        
        # First check if the model exists and belongs to the user
        model_check = supabase.from_("Generated_Models").select("generated_model_id, user_id, model_name").eq("generated_model_id", model_id_int).eq("user_id", current_user.id).limit(1).execute()
        
        if not model_check.data:
            raise HTTPException(status_code=404, detail="Model not found or you do not have permission to delete it.")
        
        # Delete associated model files first
        files_delete_result = supabase.from_("Model_Files").delete().eq("generated_model_id", model_id_int).eq("user_id", current_user.id).execute()
        
        # Log how many files were deleted
        files_deleted_count = len(files_delete_result.data) if files_delete_result.data else 0
        if files_deleted_count > 0:
            logging.info(f"Deleted {files_deleted_count} model file(s) for model {generated_model_id}")
        
        # Delete the model record
        delete_result = supabase.from_("Generated_Models").delete().eq("generated_model_id", model_id_int).eq("user_id", current_user.id).execute()

        # The delete operation should return the deleted record(s)
        if not delete_result.data:
            raise HTTPException(status_code=500, detail="Failed to delete model from database.")

        logging.info(f"Successfully deleted model {generated_model_id} for user {current_user.id}")
        
        return {
            "message": "Model and associated files deleted successfully.",
            "deleted_model_id": generated_model_id,
            "model_name": model_check.data[0].get("model_name", "Unknown"),
            "files_deleted": files_deleted_count
        }
        
    except HTTPException:
        # Re-raise HTTP exceptions as-is
        raise
    except Exception as e:
        logging.error(f"Failed to delete model {generated_model_id}: {str(e)}")
        raise HTTPException(status_code=500, detail=f"Internal server error: {str(e)}")