import streamlit as st
import tempfile
import subprocess
import os
import requests
import base64
import sys
import shutil
import re
import logging
import platform
from streamlit_ace import st_ace

# Set up logging
logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s')
logger = logging.getLogger('blender_app')

st.set_page_config(page_title="Blender 3D Viewer", layout="wide")
st.title("🌍 Blender Script → 3D Viewer")

# Detect environment
IS_HUGGINGFACE = os.environ.get('SPACE_ID') is not None
if IS_HUGGINGFACE:
    st.info("Running in Hugging Face Spaces environment")

# Find Blender executable with enhanced detection for Hugging Face
def find_blender():
    # Common paths to check, expanded for Hugging Face environment
    paths_to_check = [
        "blender",  # default PATH
        "/usr/bin/blender",
        "/opt/blender/blender",
        "/app/bin/blender",  # Common in Docker containers
        "/usr/local/bin/blender",
        os.path.join(os.path.expanduser("~"), "blender/blender")
    ]
    
    # On HF, Blender might be installed in a custom location
    if IS_HUGGINGFACE:
        # Check if Blender was installed via apt.txt
        hf_paths = [
            "/opt/conda/bin/blender",
            "/home/user/blender/blender"
        ]
        paths_to_check = hf_paths + paths_to_check
    
    # On Windows systems
    if platform.system() == "Windows":
        program_files = os.environ.get("ProgramFiles", "C:\\Program Files")
        paths_to_check.append(os.path.join(program_files, "Blender Foundation", "Blender", "blender.exe"))
    
    for path in paths_to_check:
        try:
            logger.info(f"Checking Blender at: {path}")
            result = subprocess.run([path, "--version"], 
                                   capture_output=True, 
                                   text=True,
                                   timeout=10)
            if result.returncode == 0:
                st.success(f"Found Blender: {result.stdout.strip()}")
                logger.info(f"Blender found at {path}: {result.stdout.strip()}")
                return path
        except Exception as e:
            logger.debug(f"Failed to find Blender at {path}: {str(e)}")
            continue
    
    # If not found, try using the 'which' command on Unix-like systems
    if platform.system() != "Windows":
        try:
            result = subprocess.run(["which", "blender"], 
                                    capture_output=True, 
                                    text=True,
                                    timeout=5)
            if result.returncode == 0 and result.stdout.strip():
                path = result.stdout.strip()
                st.success(f"Found Blender using 'which': {path}")
                logger.info(f"Blender found using 'which': {path}")
                return path
        except Exception as e:
            logger.debug(f"Failed to use 'which' to find Blender: {str(e)}")
    
    return None

# Enhanced script preprocessor to ensure reliable .blend file saving
def preprocess_script(script_text, tmp_dir):
    logger.info("Preprocessing script...")
    
    # Check if necessary imports exist in the script
    required_imports = {
        'import bpy': 'import bpy',
        'import os': 'import os',
        'import math': 'import math' if 'math.' in script_text else None,
        'import sys': 'import sys'
    }
    
    for import_check, import_statement in required_imports.items():
        if import_statement and import_check not in script_text:
            script_text = import_statement + '\n' + script_text
            logger.info(f"Added {import_statement} to script")
    
    # Ensure absolute paths for file operations in Hugging Face environment
    absolute_tmp_dir = os.path.abspath(tmp_dir)
    logger.info(f"Using absolute temp directory: {absolute_tmp_dir}")
    
    # More robust file saving code with error handling
    if 'bpy.ops.wm.save_as_mainfile' not in script_text:
        # Add enhanced file saving code at the end with detailed error handling
        script_text += f'''

# Save the .blend file with error handling
try:
    # Ensure the output directory exists
    output_dir = os.environ.get('BLENDER_OUTPUT_DIR', '{absolute_tmp_dir}')
    os.makedirs(output_dir, exist_ok=True)
    
    # Use absolute path for the blend file
    blend_file_path = os.path.abspath(os.path.join(output_dir, "scene.blend"))
    
    # Print debug info for troubleshooting
    print(f"Attempting to save blend file to: {{blend_file_path}}")
    print(f"Current working directory: {{os.getcwd()}}")
    
    # Save the file with absolute path - using both filepath and check_existing parameters
    bpy.ops.wm.save_as_mainfile(filepath=blend_file_path, check_existing=False)
    
    # Verify the file was saved
    if os.path.exists(blend_file_path):
        print(f"Successfully saved blend file to: {{blend_file_path}}")
    else:
        print(f"ERROR: Failed to save blend file - file does not exist after save operation")
except Exception as e:
    print(f"ERROR saving .blend file: {{str(e)}}")
    import traceback
    traceback.print_exc()
'''
        logger.info("Added enhanced file saving code to script")
    else:
        # Make sure existing save code uses absolute paths correctly and has error handling
        save_pattern = r'bpy\.ops\.wm\.save_as_mainfile\s*\(\s*filepath\s*=\s*["\']([^"\']+)["\']'
        if re.search(save_pattern, script_text):
            script_text = re.sub(
                save_pattern,
                f'bpy.ops.wm.save_as_mainfile(filepath=os.path.abspath(os.path.join(os.environ.get("BLENDER_OUTPUT_DIR", "{absolute_tmp_dir}"), "scene.blend")), check_existing=False',
                script_text
            )
            logger.info("Modified existing save code to use absolute paths")
    
    return script_text

# Check if Blender is available at startup
blender_path = find_blender()
if not blender_path:
    st.error("❌ Blender not found! The app requires Blender to be installed.")
    if IS_HUGGINGFACE:
        st.info("For Hugging Face Spaces, make sure to include 'blender' in your apt.txt file to install Blender.")
        st.code("blender", language="text")
    else:
        st.info("Please install Blender and make sure it's in your PATH.")
    # Continue anyway to show the interface

# Hardcoded default texture URLs (with fallbacks)
DEFAULT_TEXTURE_URLS = [
    "https://eoimages.gsfc.nasa.gov/images/imagerecords/57000/57730/land_ocean_ice_2048.jpg",
    "https://svs.gsfc.nasa.gov/vis/a000000/a002900/a002915/bluemarble-2048.png",
    # Additional fallbacks
    "https://upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Blue_Marble_2007_East.jpg/600px-Blue_Marble_2007_East.jpg",
    "https://www.solarsystemscope.com/textures/download/2k_earth_daymap.jpg"
]

# Sidebar: Blender script editor with example script
default_script = """import bpy
import math

# Clear the scene
bpy.ops.object.select_all(action='SELECT')
bpy.ops.object.delete()

# Create a UV Sphere for Earth
bpy.ops.mesh.primitive_uv_sphere_add(radius=1, location=(0, 0, 0))
earth = bpy.context.active_object
earth.name = 'Earth'

# Apply material to Earth
mat = bpy.data.materials.new(name="EarthMaterial")
mat.use_nodes = True
nodes = mat.node_tree.nodes
links = mat.node_tree.links

# Clear default nodes
for node in nodes:
    nodes.remove(node)

# Create texture node
texture_node = nodes.new(type='ShaderNodeTexImage')

# Get texture path from environment variable if available
texture_paths = os.environ.get('TEXTURE_PATHS', '').split(',')
if texture_paths and texture_paths[0]:
    texture_node.image = bpy.data.images.load(texture_paths[0])
    
# Add Principled BSDF node
principled = nodes.new(type='ShaderNodeBsdfPrincipled')
principled.inputs['Specular'].default_value = 0.1
principled.inputs['Roughness'].default_value = 0.8

# Add Output node
output = nodes.new(type='ShaderNodeOutputMaterial')

# Link nodes
links.new(texture_node.outputs['Color'], principled.inputs['Base Color'])
links.new(principled.outputs['BSDF'], output.inputs['Surface'])

# Assign material to Earth
if earth.data.materials:
    earth.data.materials[0] = mat
else:
    earth.data.materials.append(mat)

# Add a simple animation - rotation
earth.rotation_euler = (0, 0, 0)
earth.keyframe_insert(data_path="rotation_euler", frame=1)

# Rotate 360 degrees on Z axis
earth.rotation_euler = (0, 0, math.radians(360))
earth.keyframe_insert(data_path="rotation_euler", frame=250)

# Set animation interpolation to linear
for fc in earth.animation_data.action.fcurves:
    for kf in fc.keyframe_points:
        kf.interpolation = 'LINEAR'

# Setup camera
bpy.ops.object.camera_add(location=(0, -3, 0))
camera = bpy.context.active_object
camera.rotation_euler = (math.radians(90), 0, 0)
bpy.context.scene.camera = camera

# Setup lighting
bpy.ops.object.light_add(type='SUN', location=(5, -5, 5))
light = bpy.context.active_object
light.data.energy = 2.0

# Set render settings
bpy.context.scene.render.engine = 'CYCLES'
bpy.context.scene.cycles.device = 'CPU'
bpy.context.scene.render.film_transparent = True

# Set frame range for animation
bpy.context.scene.frame_start = 1
bpy.context.scene.frame_end = 250
"""

# Sidebar: Blender script examples
script_examples = {
    "Earth with Texture": default_script,
    "Solar System": """import bpy
import math

# Clear existing objects
bpy.ops.object.select_all(action='SELECT')
bpy.ops.object.delete(use_global=False)

# Function to create a sphere (planet or sun)
def create_celestial_body(name, radius, location, color):
    # Create mesh sphere
    bpy.ops.mesh.primitive_uv_sphere_add(radius=radius, location=location)
    obj = bpy.context.active_object
    obj.name = name
    
    # Create material
    mat = bpy.data.materials.new(name + "_Material")
    mat.use_nodes = True
    bsdf = mat.node_tree.nodes.get('Principled BSDF')
    bsdf.inputs['Base Color'].default_value = (*color, 1)
    bsdf.inputs['Roughness'].default_value = 0.5
    
    # Assign material
    if obj.data.materials:
        obj.data.materials[0] = mat
    else:
        obj.data.materials.append(mat)
    return obj

# Create the Sun (yellow)
sun = create_celestial_body('Sun', radius=2, location=(0,0,0), color=(1.0, 1.0, 0.0))

# Create an empty at origin to parent planets for orbiting
def create_orbit_empty(name):
    bpy.ops.object.empty_add(type='PLAIN_AXES', location=(0,0,0))
    empty = bpy.context.active_object
    empty.name = name
    return empty

# Planet definitions: name, radius, distance from sun, color, orbital period in frames
planets = [
    ('Mercury', 0.3, 4, (0.8, 0.5, 0.2), 88),
    ('Venus',   0.5, 6, (1.0, 0.8, 0.0), 224),
    ('Earth',   0.5, 8, (0.2, 0.4, 1.0), 365),
    ('Mars',    0.4, 10,(1.0, 0.3, 0.2), 687)
]

for name, radius, distance, color, period in planets:
    # Create orbit controller
    orbit_empty = create_orbit_empty(name + '_Orbit')
    
    # Create planet as child of orbit empty
    planet = create_celestial_body(name, radius, location=(distance, 0, 0), color=color)
    planet.parent = orbit_empty
    
    # Animate the orbit: rotate empty around Z
    orbit_empty.rotation_euler = (0, 0, 0)
    orbit_empty.keyframe_insert(data_path='rotation_euler', frame=1, index=2)
    orbit_empty.rotation_euler = (0, 0, math.radians(360))
    orbit_empty.keyframe_insert(data_path='rotation_euler', frame=period, index=2)
    
    # Set linear interpolation for smooth constant motion
    action = orbit_empty.animation_data.action
    fcurve = action.fcurves.find('rotation_euler', index=2)
    if fcurve:
        for kp in fcurve.keyframe_points:
            kp.interpolation = 'LINEAR'

# Set scene frames
bpy.context.scene.frame_start = 1
bpy.context.scene.frame_end = 687  # Use Mars' period as the end frame

# Add simple starfield as world background
world = bpy.context.scene.world
world.use_nodes = True
bg = world.node_tree.nodes['Background']
bg.inputs['Color'].default_value = (0, 0, 0, 1)

# Set up a better camera view
bpy.ops.object.camera_add(location=(0, -20, 15))
camera = bpy.context.active_object
camera.rotation_euler = (math.radians(55), 0, 0)
bpy.context.scene.camera = camera

# Add a sun light
bpy.ops.object.light_add(type='SUN', location=(10, -10, 10))
sun_light = bpy.context.active_object
sun_light.data.energy = 5.0

# Set render settings
bpy.context.scene.render.engine = 'CYCLES'
bpy.context.scene.cycles.device = 'CPU'

print('Solar system animation setup complete.')""",

    "Simple Cube (Test)": """import bpy
import math

# Clear the scene
bpy.ops.object.select_all(action='SELECT')
bpy.ops.object.delete()

# Create a cube
bpy.ops.mesh.primitive_cube_add(size=1, location=(0, 0, 0))
cube = bpy.context.active_object
cube.name = 'TestCube'

# Add animation
cube.rotation_euler = (0, 0, 0)
cube.keyframe_insert(data_path="rotation_euler", frame=1)
cube.rotation_euler = (0, math.radians(360), 0)
cube.keyframe_insert(data_path="rotation_euler", frame=100)

# Setup camera
bpy.ops.object.camera_add(location=(0, -3, 0))
camera = bpy.context.active_object
camera.rotation_euler = (math.radians(90), 0, 0)
bpy.context.scene.camera = camera

# Setup lighting
bpy.ops.object.light_add(type='SUN', location=(5, -5, 5))

# Set frame range
bpy.context.scene.frame_start = 1
bpy.context.scene.frame_end = 100
"""
}

# Add a more animation-focused example
script_examples["Animated Character"] = """import bpy
import math

# Clear existing objects
bpy.ops.object.select_all(action='SELECT')
bpy.ops.object.delete(use_global=False)

# Create simple character with basic armature
def create_simple_character():
    # Create a body (cylinder)
    bpy.ops.mesh.primitive_cylinder_add(radius=0.5, depth=2, location=(0, 0, 1))
    body = bpy.context.active_object
    body.name = "Body"
    
    # Create a head (sphere)
    bpy.ops.mesh.primitive_uv_sphere_add(radius=0.5, location=(0, 0, 2.5))
    head = bpy.context.active_object
    head.name = "Head"
    
    # Create arms (cylinders)
    bpy.ops.mesh.primitive_cylinder_add(radius=0.2, depth=1.5, location=(0.8, 0, 1.5))
    arm_right = bpy.context.active_object
    arm_right.name = "ArmRight"
    arm_right.rotation_euler = (0, math.radians(90), 0)
    
    bpy.ops.mesh.primitive_cylinder_add(radius=0.2, depth=1.5, location=(-0.8, 0, 1.5))
    arm_left = bpy.context.active_object
    arm_left.name = "ArmLeft"
    arm_left.rotation_euler = (0, math.radians(90), 0)
    
    # Create legs (cylinders)
    bpy.ops.mesh.primitive_cylinder_add(radius=0.25, depth=1, location=(0.3, 0, 0))
    leg_right = bpy.context.active_object
    leg_right.name = "LegRight"
    
    bpy.ops.mesh.primitive_cylinder_add(radius=0.25, depth=1, location=(-0.3, 0, 0))
    leg_left = bpy.context.active_object
    leg_left.name = "LegLeft"
    
    return {
        "body": body,
        "head": head,
        "arm_right": arm_right,
        "arm_left": arm_left,
        "leg_right": leg_right,
        "leg_left": leg_left
    }

# Create character
character = create_simple_character()

# Create dance animation
def create_dance_animation():
    # Set frame range
    bpy.context.scene.frame_start = 1
    bpy.context.scene.frame_end = 60
    
    # Arm waving
    # Frame 1
    bpy.context.scene.frame_set(1)
    character["arm_right"].rotation_euler = (0, math.radians(90), 0)
    character["arm_left"].rotation_euler = (0, math.radians(90), 0)
    character["arm_right"].keyframe_insert(data_path="rotation_euler")
    character["arm_left"].keyframe_insert(data_path="rotation_euler")
    
    # Frame 15
    bpy.context.scene.frame_set(15)
    character["arm_right"].rotation_euler = (0, math.radians(90), math.radians(45))
    character["arm_left"].rotation_euler = (0, math.radians(90), math.radians(-45))
    character["arm_right"].keyframe_insert(data_path="rotation_euler")
    character["arm_left"].keyframe_insert(data_path="rotation_euler")
    
    # Frame 30
    bpy.context.scene.frame_set(30)
    character["arm_right"].rotation_euler = (0, math.radians(90), math.radians(-45))
    character["arm_left"].rotation_euler = (0, math.radians(90), math.radians(45))
    character["arm_right"].keyframe_insert(data_path="rotation_euler")
    character["arm_left"].keyframe_insert(data_path="rotation_euler")
    
    # Frame 45
    bpy.context.scene.frame_set(45)
    character["arm_right"].rotation_euler = (0, math.radians(90), math.radians(45))
    character["arm_left"].rotation_euler = (0, math.radians(90), math.radians(-45))
    character["arm_right"].keyframe_insert(data_path="rotation_euler")
    character["arm_left"].keyframe_insert(data_path="rotation_euler")
    
    # Frame 60
    bpy.context.scene.frame_set(60)
    character["arm_right"].rotation_euler = (0, math.radians(90), 0)
    character["arm_left"].rotation_euler = (0, math.radians(90), 0)
    character["arm_right"].keyframe_insert(data_path="rotation_euler")
    character["arm_left"].keyframe_insert(data_path="rotation_euler")
    
    # Body bounce
    # Frame 1
    bpy.context.scene.frame_set(1)
    character["body"].location = (0, 0, 1)
    character["body"].keyframe_insert(data_path="location")
    character["head"].location = (0, 0, 2.5)
    character["head"].keyframe_insert(data_path="location")
    
    # Frame 15
    bpy.context.scene.frame_set(15)
    character["body"].location = (0, 0, 1.2)
    character["body"].keyframe_insert(data_path="location")
    character["head"].location = (0, 0, 2.7)
    character["head"].keyframe_insert(data_path="location")
    
    # Frame 30
    bpy.context.scene.frame_set(30)
    character["body"].location = (0, 0, 1)
    character["body"].keyframe_insert(data_path="location")
    character["head"].location = (0, 0, 2.5)
    character["head"].keyframe_insert(data_path="location")
    
    # Frame 45
    bpy.context.scene.frame_set(45)
    character["body"].location = (0, 0, 1.2)
    character["body"].keyframe_insert(data_path="location")
    character["head"].location = (0, 0, 2.7)
    character["head"].keyframe_insert(data_path="location")
    
    # Frame 60
    bpy.context.scene.frame_set(60)
    character["body"].location = (0, 0, 1)
    character["body"].keyframe_insert(data_path="location")
    character["head"].location = (0, 0, 2.5)
    character["head"].keyframe_insert(data_path="location")
    
    # Set interpolation
    for obj in character.values():
        if obj.animation_data and obj.animation_data.action:
            for fc in obj.animation_data.action.fcurves:
                for kp in fc.keyframe_points:
                    kp.interpolation = 'BEZIER'

# Create the animation
create_dance_animation()

# Set up camera and lighting
bpy.ops.object.camera_add(location=(0, -5, 2))
camera = bpy.context.active_object
camera.rotation_euler = (math.radians(80), 0, 0)
bpy.context.scene.camera = camera

# Add light
bpy.ops.object.light_add(type='SUN', location=(2, -3, 5))
sun = bpy.context.active_object
sun.data.energy = 3.0

# Set render settings
bpy.context.scene.render.engine = 'CYCLES'
bpy.context.scene.cycles.device = 'CPU'

print('Character animation setup complete')
"""

# Add example selector
selected_example = st.sidebar.selectbox(
    "Load example script:",
    options=list(script_examples.keys())
)

# Sidebar: Blender script editor
st.sidebar.header("Blender Python Script")
script_text = st_ace(
    value=script_examples[selected_example],
    placeholder="Paste your Blender Python script here...",
    language="python",
    theme="monokai",
    key="ace",
    min_lines=20,
    max_lines=100,
)

# Sidebar: texture uploads
st.sidebar.header("Texture Uploads (JPG/PNG)")
uploaded_textures = st.sidebar.file_uploader(
    "Upload one or more textures", type=["jpg", "jpeg", "png"], accept_multiple_files=True
)

# Sidebar: custom Python libraries
st.sidebar.header("Custom Python Libraries")
custom_packages = st.sidebar.text_area(
    "List pip packages (one per line)",
    height=100
)

# Add options specific to troubleshooting in Hugging Face
if IS_HUGGINGFACE:
    st.sidebar.header("Hugging Face Options")
    debug_mode = st.sidebar.checkbox("Enable Debug Mode", value=False)
    if debug_mode:
        log_level = st.sidebar.selectbox(
            "Log Level", 
            options=["INFO", "DEBUG"], 
            index=0
        )
        if log_level == "DEBUG":
            logger.setLevel(logging.DEBUG)

# Main action
if st.sidebar.button("Run & Export GLB"):
    if not blender_path:
        st.error("Cannot proceed: Blender is not available")
        st.stop()
        
    if not script_text or not script_text.strip():
        st.error("Please provide a valid Blender Python script.")
        st.stop()
    
    with st.spinner("Processing your 3D scene..."):
        # Use a more robust temporary directory approach
        tmp_dir = tempfile.mkdtemp(prefix="blender_app_")
        logger.info(f"Created temporary directory: {tmp_dir}")
        
        try:
            # 1) Preprocess and save user script
            processed_script = preprocess_script(script_text, tmp_dir)
            script_path = os.path.join(tmp_dir, "user_script.py")
            with open(script_path, "w") as f:
                f.write(processed_script)
            logger.info(f"Saved processed script to: {script_path}")

            # 2) Collect textures
            texture_paths = []
            if uploaded_textures:
                for idx, upload in enumerate(uploaded_textures):
                    ext = os.path.splitext(upload.name)[1]
                    path = os.path.join(tmp_dir, f"texture_{idx}{ext}")
                    with open(path, "wb") as tf:
                        tf.write(upload.read())
                    texture_paths.append(path)
                logger.info(f"Saved {len(texture_paths)} uploaded textures")
            else:
                # Try multiple default textures if some fail
                for url in DEFAULT_TEXTURE_URLS:
                    try:
                        r = requests.get(url, timeout=15)
                        r.raise_for_status()
                        ext = os.path.splitext(url)[-1] or ".jpg"
                        path = os.path.join(tmp_dir, f"default{ext}")
                        with open(path, "wb") as tf:
                            tf.write(r.content)
                        texture_paths.append(path)
                        logger.info(f"Downloaded texture from {url}")
                        # If we got one texture successfully, that's enough
                        break
                    except Exception as e:
                        logger.warning(f"Could not download texture {url}: {str(e)}")
                        st.warning(f"Could not download texture {url}: {str(e)}")

            # Display texture file information
            if texture_paths:
                st.subheader("Texture Files")
                for tp in texture_paths:
                    st.code(os.path.basename(tp))
                    logger.info(f"Using texture: {tp}")
            else:
                st.warning("No textures were loaded. Your 3D model may appear without textures.")
                logger.warning("No textures were loaded")

            # 3) Install custom Python libraries if specified
            if custom_packages and custom_packages.strip():
                pkgs = [l.strip() for l in custom_packages.splitlines() if l.strip()]
                if pkgs:
                    st.info(f"Installing: {', '.join(pkgs)}")
                    logger.info(f"Installing packages: {', '.join(pkgs)}")
                    try:
                        # Use Python executable from current environment for pip
                        pip_cmd = [sys.executable, "-m", "pip", "install", "--user"] + pkgs
                        pip_res = subprocess.run(
                            pip_cmd,
                            check=True,
                            capture_output=True,
                            text=True,
                            timeout=180  # 3 minute timeout
                        )
                        st.text_area("pip install output", pip_res.stdout + pip_res.stderr, height=100)
                        logger.info(f"Pip install result: {pip_res.returncode}")
                    except Exception as e:
                        st.warning(f"pip install failed: {str(e)}")
                        logger.error(f"pip install failed: {str(e)}")

            # 4) Prepare environment with necessary variables
            env = os.environ.copy()
            env["TEXTURE_PATHS"] = ",".join(texture_paths)
            env["BLENDER_OUTPUT_DIR"] = tmp_dir  # Pass the tmp_dir to the Blender script
            logger.info(f"Set environment variable BLENDER_OUTPUT_DIR={tmp_dir}")
            
            # 5) Run Blender to build .blend file with enhanced error handling and retry
            blend_path = os.path.join(tmp_dir, "scene.blend")
            
            max_retries = 3
            for attempt in range(1, max_retries + 1):
                with st.status(f"Running Blender to create scene (attempt {attempt}/{max_retries})...") as status:
                    cmd1 = [blender_path, "--background", "--python", script_path]
                    logger.info(f"Running Blender command: {' '.join(cmd1)}")
                    
                    try:
                        r1 = subprocess.run(
                            cmd1,
                            cwd=tmp_dir,
                            env=env,
                            check=True,
                            capture_output=True,
                            text=True,
                            timeout=300  # 5 minute timeout
                        )
                        status.update(label=f"Blender scene created successfully (attempt {attempt})", state="complete")
                        st.text_area("Blender output", r1.stdout + r1.stderr, height=150)
                        logger.info("Blender script execution completed successfully")
                        break
                    except subprocess.TimeoutExpired:
                        st.error(f"Blender process timed out after 5 minutes (attempt {attempt}/{max_retries}).")
                        logger.error(f"Blender timeout on attempt {attempt}")
                        if attempt == max_retries:
                            st.stop()
                    except subprocess.CalledProcessError as e:
                        st.error(f"Blender build failed with error code {e.returncode} (attempt {attempt}/{max_retries})")
                        st.text_area("Error details", e.stdout + e.stderr, height=150)
                        logger.error(f"Blender error on attempt {attempt}: {e.returncode}")
                        logger.debug(f"Blender stderr: {e.stderr}")
                        
                        # If it's the last attempt, stop execution
                        if attempt == max_retries:
                            st.stop()
                    except Exception as e:
                        st.error(f"Blender build failed: {str(e)} (attempt {attempt}/{max_retries})")
                        logger.error(f"Unexpected error on attempt {attempt}: {str(e)}")
                        if attempt == max_retries:
                            st.stop()
            
            # Check if blend file was created with better diagnostics
            if not os.path.exists(blend_path):
                st.error("Blender did not create the expected scene.blend file.")
                logger.error(f"Blend file not found at {blend_path}")
                
                # Check directory contents for troubleshooting
                dir_contents = os.listdir(tmp_dir)
                logger.info(f"Temporary directory contents: {dir_contents}")
                st.info(f"Temporary directory contents: {', '.join(dir_contents)}")
                
                # Try an alternative approach by writing a minimal script just to save a file
                st.warning("Attempting alternative approach to create .blend file...")
                logger.info("Trying alternative approach with minimal script")
                
                minimal_script_path = os.path.join(tmp_dir, "minimal_save.py")
                with open(minimal_script_path, "w") as f:
                    f.write(f"""
import bpy
import os

# Make sure the directory exists
os.makedirs(r'{tmp_dir}', exist_ok=True)

# Create a simple cube
bpy.ops.mesh.primitive_cube_add(size=1, location=(0, 0, 0))

# Save the file
blend_path = r'{blend_path}'
print(f"Saving to {{blend_path}}")
bpy.ops.wm.save_as_mainfile(filepath=blend_path, check_existing=False)
print(f"Save operation completed, checking if file exists: {{os.path.exists(blend_path)}}")
""")
                
                try:
                    cmd_min = [blender_path, "--background", "--python", minimal_script_path]
                    r_min = subprocess.run(
                        cmd_min,
                        cwd=tmp_dir,
                        env=env,
                        check=True,
                        capture_output=True,
                        text=True,
                        timeout=120
                    )
                    st.text_area("Minimal script output", r_min.stdout + r_min.stderr, height=150)
                    logger.info("Minimal script execution completed")
                    
                    if os.path.exists(blend_path):
                        st.success("Alternative approach created a .blend file successfully!")
                        logger.info("Alternative approach succeeded")
                    else:
                        st.error("Alternative approach also failed to create .blend file.")
                        logger.error("Alternative approach failed")
                        st.stop()
                except Exception as e:
                    st.error(f"Alternative approach failed: {str(e)}")
                    logger.error(f"Alternative approach error: {str(e)}")
                    st.stop()
                
            # 6) Export GLB with animation - enhanced error handling and animation support
            glb_path = os.path.join(tmp_dir, "animation.glb")
            
            with st.status("Exporting to GLB format with animations...") as status:
                # Create a separate Python script for enhanced GLB export with better animation support
                export_script = os.path.join(tmp_dir, "export_glb.py")
                with open(export_script, "w") as f:
                    f.write(f"""
import bpy
import os
import sys

# Print debug info
print(f"Python version: {{sys.version}}")
print(f"Blender version: {{bpy.app.version_string}}")
print(f"Attempting to load blend file: {blend_path}")
print(f"Current working directory: {{os.getcwd()}}")
print(f"File exists check: {{os.path.exists(r'{blend_path}')}}") 

try:
    # Load the blend file
    bpy.ops.wm.open_mainfile(filepath=r'{blend_path}')
    print("Blend file loaded successfully")
    
    # Get animation info
    scene = bpy.context.scene
    frame_start = scene.frame_start
    frame_end = scene.frame_end
    fps = scene.render.fps
    print(f"Animation frames: {{frame_start}}-{{frame_end}} at {{fps}} fps")
    
    # Export to GLB with enhanced animation options
    glb_path = r'{glb_path}'
    print(f"Exporting to GLB: {{glb_path}}")
    
    # Check if glTF export is available
    if hasattr(bpy.ops.export_scene, 'gltf'):
        bpy.ops.export_scene.gltf(
            filepath=glb_path,
            export_format='GLB',
            export_animations=True,
            export_frame_range=True,
            export_frame_step=1,
            export_anim_single_armature=False,  # Export all animations
            export_current_frame=False,
            export_apply=False  # Keep animations intact
        )
        print(f"GLB export completed, file exists: {{os.path.exists(glb_path)}}")
    else:
        print("ERROR: glTF export operator not available. Check if the add-on is enabled.")
        # Try to enable the addon
        bpy.ops.preferences.addon_enable(module='io_scene_gltf2')
        print("Attempted to enable glTF add-on")
        
        # Try export again
        if hasattr(bpy.ops.export_scene, 'gltf'):
            bpy.ops.export_scene.gltf(
                filepath=glb_path,
                export_format='GLB',
                export_animations=True,
                export_frame_range=True,
                export_frame_step=1,
                export_anim_single_armature=False,
                export_current_frame=False,
                export_apply=False
            )
            print(f"GLB export completed after enabling add-on")
        else:
            print("ERROR: Could not enable glTF export add-on")
except Exception as e:
    print(f"ERROR during export: {{str(e)}}")
    import traceback
    traceback.print_exc()
""")
                
                cmd2 = [blender_path, "--background", "--python", export_script]
                logger.info(f"Running GLB export command: {' '.join(cmd2)}")
                
                try:
                    r2 = subprocess.run(
                        cmd2,
                        cwd=tmp_dir,
                        env=env,
                        check=True,
                        capture_output=True,
                        text=True,
                        timeout=180  # 3 minute timeout
                    )
                    status.update(label="GLB export with animations completed successfully", state="complete")
                    st.text_area("Export output", r2.stdout + r2.stderr, height=100)
                    logger.info("GLB export completed successfully")
                except Exception as e:
                    st.error(f"GLB export failed: {str(e)}")
                    logger.error(f"GLB export error: {str(e)}")
                    st.stop()

            # 7) Embed GLB inline with enhanced animation viewer
            if os.path.exists(glb_path):
                with open(glb_path, 'rb') as f:
                    data = f.read()
                
                file_size = len(data) / (1024 * 1024)  # Size in MB
                st.success(f"Successfully created GLB file with animations ({file_size:.1f} MB)")
                logger.info(f"Created GLB file, size: {file_size:.1f} MB")
                
                # Check if file isn't too large for embedding
                if file_size > 50:
                    st.warning("The GLB file is quite large. The viewer might be slow to load.")
                    logger.warning(f"Large GLB file: {file_size:.1f} MB")
                
                b64 = base64.b64encode(data).decode()
                
                # Display the 3D model viewer with animation controls
                st.subheader("3D Model Viewer with Animation Controls")
                html = f"""
<script type="module" src="https://unpkg.com/@google/model-viewer@latest/dist/model-viewer.min.js"></script>
<style>
    .animation-controls {{
        display: flex;
        justify-content: center;
        margin-top: 10px;
        gap: 8px;
    }}
    .animation-btn {{
        background-color: #4CAF50;
        border: none;
        color: white;
        padding: 8px 16px;
        text-align: center;
        text-decoration: none;
        display: inline-block;
        font-size: 14px;
        margin: 4px 2px;
        cursor: pointer;
        border-radius: 4px;
    }}
    #animation-name {{
        font-weight: bold;
        margin-right: 10px;
    }}
</style>

<model-viewer id="model-viewer"
    src="data:model/gltf-binary;base64,{b64}" 
    alt="3D Model with Animation" 
    camera-controls
    auto-rotate
    ar
    shadow-intensity="1"
    animation-name=""
    autoplay
    style="width:100%; height:500px; background-color: #f0f0f0;">
    <div class="progress-bar hide" slot="progress-bar">
        <div class="update-bar"></div>
    </div>
</model-viewer>

<div class="animation-controls">
    <span id="animation-name">No animation playing</span>
    <button id="play-btn" class="animation-btn">Play</button>
    <button id="pause-btn" class="animation-btn">Pause</button>
    <button id="stop-btn" class="animation-btn">Stop</button>
</div>

<script>
    const modelViewer = document.getElementById('model-viewer');
    const playBtn = document.getElementById('play-btn');
    const pauseBtn = document.getElementById('pause-btn');
    const stopBtn = document.getElementById('stop-btn');
    const animNameDisplay = document.getElementById('animation-name');
    
    // Wait for the model to load
    modelViewer.addEventListener('load', () => {{
        // Get available animations
        const animationNames = modelViewer.availableAnimations;
        console.log('Available animations:', animationNames);
        
        if (animationNames && animationNames.length > 0) {{
            // Set first animation as default
            modelViewer.animationName = animationNames[0];
            animNameDisplay.textContent = 'Playing: ' + animationNames[0];
            modelViewer.play();
        }} else {{
            animNameDisplay.textContent = 'No animations available';
        }}
    }});
    
    // Animation controls
    playBtn.addEventListener('click', () => {{
        modelViewer.play();
        if (modelViewer.animationName) {{
            animNameDisplay.textContent = 'Playing: ' + modelViewer.animationName;
        }}
    }});
    
    pauseBtn.addEventListener('click', () => {{
        modelViewer.pause();
        if (modelViewer.animationName) {{
            animNameDisplay.textContent = 'Paused: ' + modelViewer.animationName;
        }}
    }});
    
    stopBtn.addEventListener('click', () => {{
        modelViewer.pause();
        modelViewer.currentTime = 0;
        if (modelViewer.animationName) {{
            animNameDisplay.textContent = 'Stopped: ' + modelViewer.animationName;
        }}
    }});
</script>
"""
                st.components.v1.html(html, height=600)
                
                # Add download button
                st.download_button(
                    "⬇️ Download GLB File with Animation", 
                    data, 
                    file_name="animation.glb",
                    mime="model/gltf-binary"
                )
            else:
                st.error("GLB file was not generated successfully.")
                logger.error(f"GLB file not found at {glb_path}")
                
                if os.path.exists(blend_path):
                    st.info("The Blender file was created, but the GLB export failed.")
                    logger.info("Blend file exists but GLB export failed")
                
        finally:
            # Clean up - remove temporary directory if not in debug mode
            if IS_HUGGINGFACE and debug_mode:
                st.info(f"Debug mode: Temporary files kept at {tmp_dir}")
                logger.info(f"Keeping temp files for debugging: {tmp_dir}")
            else:
                try:
                    shutil.rmtree(tmp_dir, ignore_errors=True)
                    logger.info(f"Cleaned up temporary directory: {tmp_dir}")
                except Exception as e:
                    st.warning(f"Failed to clean up temporary files: {str(e)}")
                    logger.error(f"Cleanup error: {str(e)}")

# Add helpful information at the bottom
st.divider()
with st.expander("About this app"):
    st.markdown("""
    **Blender 3D Viewer App** lets you:
    
    - Write Blender Python scripts directly in your browser
    - Upload custom textures for your 3D models
    - Generate and visualize 3D models with animations
    - Download the results as GLB files for use in other applications
    
    The app automatically adds necessary imports and file saving code to your scripts,
    so you can focus on creating 3D content without worrying about environment details.
    
    Running on Hugging Face Spaces: This app requires Blender to be installed. Make sure
    your Space includes 'blender' in the apt.txt file.
    """)
    
with st.expander("Script Tips"):
    st.markdown("""
    ### Tips for writing Blender scripts
    
    1. **Accessing textures**: Use the environment variable `TEXTURE_PATHS` to get the paths to uploaded textures
    
    ```python
    # Example code to load the first uploaded texture
    texture_paths = os.environ.get('TEXTURE_PATHS', '').split(',')
    if texture_paths and texture_paths[0]:
        image = bpy.data.images.load(texture_paths[0])
    ```
    
    2. **You don't need to add file saving code** - the app automatically adds it
    
    3. **Animations**: Make sure to set keyframes if you want your model to animate:
    
    ```python
    # Example animation (rotate object 360 degrees over 250 frames)
    obj.rotation_euler = (0, 0, 0)
    obj.keyframe_insert(data_path="rotation_euler", frame=1)
    obj.rotation_euler = (0, 0, math.radians(360))
    obj.keyframe_insert(data_path="rotation_euler", frame=250)
    ```
    
    4. **Troubleshooting in Hugging Face**: If you're having issues with the app in Hugging Face Spaces:
    
    - Enable Debug Mode in the sidebar
    - Check the error messages in the app output
    - Make sure your apt.txt file includes 'blender'
    - Try the "Simple Cube (Test)" example first to verify Blender is working
    """)

with st.expander("Animation Tips"):
    st.markdown("""
    ### Tips for creating animations that show properly in GLB

    1. **Set frame range properly**: Always define your animation frame range
    ```python
    bpy.context.scene.frame_start = 1
    bpy.context.scene.frame_end = 60  # End frame of your animation
    ```

    2. **Use keyframes properly**: Add keyframes at specific frames
    ```python
    # Set current frame
    bpy.context.scene.frame_set(1)
    
    # Set object properties
    obj.location = (0, 0, 0)
    
    # Insert keyframe for that property
    obj.keyframe_insert(data_path="location")
    ```

    3. **Animation export settings**: The app automatically handles GLB export with proper animation settings

    4. **Animation playback**: Use the animation controls below the 3D viewer to play/pause/stop your animation

    5. **Multiple animations**: If your GLB has multiple animations, they will be detected and can be selected in the viewer

    6. **Looping animations**: By default, animations will loop in the viewer
    """)

# Add a section at the bottom for Hugging Face Spaces setup
with st.expander("Hugging Face Spaces Setup"):
    st.markdown("""
    ### Setting up this app on Hugging Face Spaces
    
    To ensure this app works correctly on Hugging Face:
    
    1. **Create an apt.txt file** in your repository with:
    ```
    blender
    ```
    
    2. **Create a requirements.txt file** with:
    ```
    streamlit
    streamlit-ace
    requests
    ```
    
    3. **Set the Space SDK** to "Streamlit" in the Space settings
    
    4. **Set resource allocation** to at least 2 CPU + 4GB RAM for better performance
    
    Troubleshooting: If you encounter "Blender not found" errors, check your apt.txt file and make sure Blender is being installed correctly.
    """)