app.py

import os
import logging
import json
import tempfile
import zipfile
import gzip
import shapely.geometry
import pyprt
import glob
import shutil
from shapely.ops import transform
from shapely.affinity import translate
import functools
import math
from fastapi import FastAPI, HTTPException, Body, Request
from fastapi.responses import FileResponse, JSONResponse
from fastapi.middleware.cors import CORSMiddleware
from pydantic import BaseModel
from typing import List, Dict, Any, Optional

from fastapi.staticfiles import StaticFiles
import uuid

# Configure logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

app = FastAPI()

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # Allow all origins for now
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
    expose_headers=["X-Centroid-Lat", "X-Centroid-Lon", "X-Convergence-Angle"]
)

# Mount static directory for I3S layers
# Ensure directory exists
LAYERS_DIR = os.path.join(os.path.dirname(__file__), "static", "layers")
if not os.path.exists(LAYERS_DIR):
    os.makedirs(LAYERS_DIR)

app.mount("/layers", StaticFiles(directory=LAYERS_DIR), name="layers")

RPK_DIR = os.path.join(os.path.dirname(__file__), "rpk")

# Ensure RPK directory exists
if not os.path.exists(RPK_DIR):
    os.makedirs(RPK_DIR)

# Assets directory — textures resolved from Material API are cached here so
# PRT can reference them via absolute filesystem paths.
ASSETS_DIR = os.path.join(os.path.dirname(__file__), "assets")
if not os.path.exists(ASSETS_DIR):
    os.makedirs(ASSETS_DIR)

# Material API base URL — set via MATERIAL_API_URL env var / HF Space secret
MATERIAL_API_BASE = os.environ.get("MATERIAL_API_URL", "").rstrip("/")

# Local Materials directory — co-located in the same container/repo.
# Textures are resolved from here first (no HTTP needed), then HTTP fallback.
MATERIAL_API_ROOT = os.path.join(os.path.dirname(__file__), "material_api", "Materials")


class GenerateRequest(BaseModel):
    rpk_name: str
    geometry: Dict[str, Any]  # GeoJSON Feature or Geometry
    attributes: Dict[str, Any] = {}

class GenerateI3SRequest(BaseModel):
    rpk_name: str
    coordinates: List[float] # [lon, lat, alt, lon, lat, alt, ...]
    attributes: Dict[str, Any] = {}

def get_rpk_path(filename: str):
    path = os.path.join(RPK_DIR, filename)
    if not os.path.exists(path):
        return None
    return path

# ---------------------------------------------------------------------------
# Shared helpers
# ---------------------------------------------------------------------------

def _clean_attributes(raw: Dict[str, Any]) -> Dict[str, Any]:
    """
    Sanitise attribute values for PyPRT.

    PyPRT's CGA engine only accepts ``float | bool | str`` per attribute.
    Any value that is ``None``, a complex type (list/dict/set), or otherwise
    un-serialisable is dropped so PyPRT falls back to the CGA default value
    rather than raising an internal ``AttributeError: 'NoneType' …``.
    """
    cleaned: Dict[str, Any] = {}
    for k, v in raw.items():
        if v is None:
            continue  # drop – PyPRT will use the CGA rule default
        if isinstance(v, bool):
            cleaned[k] = bool(v)
        elif isinstance(v, float):
            cleaned[k] = float(v)
        elif isinstance(v, int):
            cleaned[k] = float(v)  # PyPRT requires float, not int
        elif isinstance(v, str):
            if v == '':
                continue  # drop empty strings – PyPRT can't handle them
            cleaned[k] = str(v)
        else:
            # Skip lists, dicts, sets, etc. — not valid CGA attribute types
            logger.warning(f"Dropping attribute '{k}' with unsupported type {type(v).__name__}")
    return cleaned


def _resolve_texture_bytes(rel_path: str) -> Optional[bytes]:
    """
    Load the raw bytes for a Material API texture path (``/texture/...``).

    Resolution order:
    1. Local filesystem: ``MATERIAL_API_ROOT / <path-without-/texture/-prefix>``
       Handles .tif/.tiff → .jpg/.png fallback (same logic as Material API).
    2. HTTP: ``MATERIAL_API_BASE + rel_path`` (only if MATERIAL_API_BASE is set).

    Returns raw bytes on success, or ``None`` if the texture cannot be found.
    """
    if not rel_path.startswith("/texture/"):
        return None

    tex_rel = rel_path[len("/texture/"):]  # e.g. "Architectural/Cladding/Aluminium/Textures/file.jpg"
    local_path = os.path.join(MATERIAL_API_ROOT, tex_rel.replace("/", os.sep))

    # .tif/.tiff → look for browser-compatible sibling (same as Material API tex_url())
    _, ext = os.path.splitext(local_path)
    if ext.lower() in (".tif", ".tiff"):
        for alt_ext in (".jpg", ".jpeg", ".png", ".webp"):
            alt = os.path.splitext(local_path)[0] + alt_ext
            if os.path.isfile(alt):
                local_path = alt
                break
        else:
            local_path = ""  # no alternative

    if local_path and os.path.isfile(local_path):
        try:
            with open(local_path, "rb") as f:
                data = f.read()
            logger.info(f"Texture resolved locally: {local_path}")
            return data
        except Exception as exc:
            logger.warning(f"Local texture read failed ({local_path}): {exc}")

    # HTTP fallback — used when Material API runs as a separate service
    if MATERIAL_API_BASE:
        url = f"{MATERIAL_API_BASE}{rel_path}"
        try:
            import requests as _requests
            resp = _requests.get(url, timeout=20)
            resp.raise_for_status()
            logger.info(f"Texture downloaded via HTTP: {url}")
            return resp.content
        except Exception as exc:
            logger.warning(f"Texture HTTP download failed ({url}): {exc}")

    return None


def _inject_textures_into_rpk(rpk_path: str, attrs: Dict[str, Any]) -> tuple:
    """
    For every texture attribute (value starts with '/texture/'):
      1. Fetch the texture bytes via _resolve_texture_bytes.
      2. Write them into a per-request subdirectory of ASSETS_DIR.
      3. Replace the attribute value with the absolute filesystem path so PRT
         loads it directly.

    Supports multiple texture attributes in one call — each is written to the
    same per-request subdirectory.

    Returns ``(rpk_path, modified_attrs, req_assets_dir)``.
    ``req_assets_dir`` is a subdirectory of ASSETS_DIR that the caller must
    delete with shutil.rmtree() after generate_model() completes.
    RPK is not modified.
    """
    texture_attrs = {
        k: v for k, v in attrs.items()
        if isinstance(v, str) and v.startswith("/texture/")
    }
    if not texture_attrs:
        return rpk_path, attrs, None

    # Isolated per-request subdirectory — keeps concurrent requests separate
    # and lets us clean up with a single shutil.rmtree() call.
    req_id = str(uuid.uuid4())
    req_assets_dir = os.path.join(ASSETS_DIR, req_id)
    os.makedirs(req_assets_dir, exist_ok=True)

    modified = dict(attrs)

    for key, rel_path in texture_attrs.items():
        tex_data = _resolve_texture_bytes(rel_path)
        if tex_data is None:
            logger.warning(f"Texture '{key}' not found — dropping, CGA will use default")
            modified.pop(key, None)
            continue

        filename = os.path.basename(rel_path)
        dest = os.path.join(req_assets_dir, filename)
        try:
            with open(dest, "wb") as f:
                f.write(tex_data)
            # PRT's CGA URI resolver supports file:// URIs for external textures.
            # Coordinate-based InitialShape has no base URI, so relative paths
            # only resolve inside the RPK. file:// is the only reliable external format.
            # On Linux: dest="/app/assets/uuid/file.jpg" → "file:///app/assets/uuid/file.jpg"
            file_uri = "file://" + dest
            modified[key] = file_uri
            logger.info(f"Texture '{key}' → {dest}  (CGA attr: '{file_uri}')")
        except Exception as exc:
            logger.warning(f"Texture write failed for '{key}': {exc} — dropping")
            modified.pop(key, None)

    return rpk_path, modified, req_assets_dir


# RPKs that control report emission via boolean attributes — always force them ON.
_RPK_REPORT_FORCE_ATTRS: Dict[str, Dict[str, Any]] = {
    "BLDG_Units.rpk": {"Reports": True, "report": True},
}

# RPKs that are geometry-only and crash PyEncoder / ignore user attributes.
# For these: skip the report-extraction pass and always generate with {} attrs.
GEOMETRY_ONLY_RPKS: set = {
    "translateModel.rpk",
}


def _ensure_report_attrs(rpk_name: str, attrs: Dict[str, Any]) -> Dict[str, Any]:
    """Merge any mandatory report-enabling attributes for the given RPK.

    Some RPKs gate their ``report()`` calls behind boolean attributes
    (``Reports``, ``report``).  This helper ensures those are always
    ``True`` so the PyEncoder pass reliably returns data.
    """
    forced = _RPK_REPORT_FORCE_ATTRS.get(rpk_name, {})
    if not forced:
        return attrs
    merged = dict(attrs)  # shallow copy
    merged.update(forced)  # override / inject
    return merged



def _extract_reports(
    initial_shape: "pyprt.InitialShape",
    clean_attrs: Dict[str, Any],
    rpk_path: str,
) -> Dict[str, Any]:
    """
    Run a dedicated PyEncoder pass (emitGeometry=False, emitReport=True) to
    collect the CGA report dictionary.

    Background
    ----------
    ``GeneratedModel.get_report()`` is **only** populated when the
    ``com.esri.pyprt.PyEncoder`` is used.  File-based encoders such as
    ``GLTFEncoder`` and ``I3SEncoder`` write geometry to disk and return an
    *empty* list from ``generate_model()``, so iterating over that list
    never reaches ``get_report()``.

    Reference: https://esri.github.io/pyprt/apidoc/pyprt.pyprt.html
    """
    reports: Dict[str, Any] = {}
    try:
        mg = pyprt.ModelGenerator([initial_shape])
        report_models = mg.generate_model(
            [clean_attrs],
            rpk_path,
            "com.esri.pyprt.PyEncoder",
            {"emitReport": True, "emitGeometry": False},
        )
        for m in report_models:
            rep = m.get_report()
            if rep:
                reports.update(rep)
        logger.info(f"CGA reports extracted: {list(reports.keys())}")
    except Exception as exc:
        logger.warning(f"Report extraction failed (non-fatal): {exc}")
    return reports

@app.get("/rpks")
async def list_rpks():
    """List available RPK files."""
    files = [f for f in os.listdir(RPK_DIR) if f.endswith(".rpk")]
    return {"rpks": files}

@app.get("/rpk/{filename}/info")
async def get_rpk_info(filename: str):
    """Get attribute information for a specific RPK."""
    rpk_path = get_rpk_path(filename)
    if not rpk_path:
        raise HTTPException(status_code=404, detail="RPK not found")

    try:
        # Get RPK attributes info using PyPRT
        attrs_info = pyprt.get_rpk_attributes_info(rpk_path)
        
        formatted_attrs = []
        
        # Handle List of Objects return type (standard PyPRT)
        if hasattr(attrs_info, '__iter__'):
             for attr in attrs_info:
                if hasattr(attr, 'get_name'):
                    name = attr.get_name()
                    attr_type = str(attr.get_type())
                    default_val = attr.get_default_value()
                    annotations = []
                    
                    if hasattr(attr, 'get_annotations'):
                        try:
                            py_annotations = attr.get_annotations()
                            logger.info(f"Attr {name} annotations: {py_annotations}")
                            for anno in py_annotations:
                                key = None
                                args = []
                                if hasattr(anno, 'get_key'):
                                    key = anno.get_key()
                                elif hasattr(anno, 'key'):
                                    key = anno.key
                                    
                                if hasattr(anno, 'get_arguments'):
                                    args = anno.get_arguments()
                                elif hasattr(anno, 'arguments'):
                                    args = anno.arguments

                                if key:
                                    annotations.append({"key": key, "arguments": args})
                        except Exception as e:
                            logger.error(f"Error fetching annotations for {name}: {e}")

                    formatted_attrs.append({
                        "name": name,
                        "type": attr_type, 
                        "defaultValue": default_val,
                        "annotations": annotations
                    })
                elif isinstance(attr, str):
                    # Fallback if list of strings
                    formatted_attrs.append({
                        "name": attr,
                        "type": "string",
                        "defaultValue": ""
                    })

        return {"attributes": formatted_attrs}
    except Exception as e:
        logger.error(f"Error inspecting RPK: {e}")
        # Return empty attributes instead of 500 if inspection fails
        return {"attributes": []}

@app.post("/generate")
async def generate_model(request: GenerateRequest):
    """Generate a 3D model from geometry and RPK."""
    rpk_path = get_rpk_path(request.rpk_name)
    if not rpk_path:
        raise HTTPException(status_code=404, detail="RPK not found")

    try:
        # Parse Geometry
        # Expected input is a GeoJSON Feature or Geometry
        geom_dict = request.geometry
        if geom_dict.get("type") == "Feature":
            geom_dict = geom_dict.get("geometry")
        
        shape = shapely.geometry.shape(geom_dict)
        
        # Create Initial Shape for PyPRT
        # PyPRT expects a list of InitialShapes. 
        # For a polygon, we pass definitions. 
        # Helper to convert Shapely polygon to PyPRT InitialShape
        
        if geom_dict.get("type") != "Polygon":
             raise HTTPException(status_code=400, detail="Only Polygons are supported")

        # 1. Validate geometry (repair if needed)
        if not shape.is_valid:
             shape = shape.buffer(0)

        # NOTE: Do NOT call shapely.ops.orient() here.
        # The frontend guarantees CCW winding via ensureCCW() (Shoelace formula).
        # Previously orient(sign=-1.0) forced CW, which caused mirroring when
        # the frontend was already sending CW or CCW depending on draw direction.
        
        # 2. Re-center Geometry
        # PyPRT generates at (0,0,0). We need to shift the polygon so its centroid is at (0,0).
        centroid = shape.centroid
        logger.info(f"Geometry Centroid: {centroid.x}, {centroid.y}")
        
        # Translate shape so centroid is at (0,0)
        shape_centered = translate(shape, xoff=-centroid.x, yoff=-centroid.y)
        
        coords = list(shape_centered.exterior.coords)
        # Remove last point if duplicate (closed loop)
        if coords[0] == coords[-1]:
            coords = coords[:-1]
            
        # 3. Flatten coordinates for PyPRT InitialShape
        # Frontend ENU convention:  x = east,  y = north
        # PyPRT/CGA convention:     X = east,  Y = height (up),  Z = south (depth, negated)
        # CGA Z increases southward, but ENU Y increases northward — negate to align.
        # Mapping: [enu_x, 0, -enu_y]  →  [CGA_X, CGA_Y=0, CGA_Z]
        flattened_coords = []
        for p in coords:
            flattened_coords.extend([p[0], 0, -p[1]])


        indices = list(range(len(coords)))
        face_counts = [len(coords)]

        # Sanitise attributes
        clean_attributes = _clean_attributes(request.attributes)
        # Inject any Material-API textures into a temp RPK copy so CGA resolves them
        rpk_path, clean_attributes, tex_temp_dir = _inject_textures_into_rpk(rpk_path, clean_attributes)
        logger.info(f"Generating with RPK: {rpk_path}")
        logger.info(f"Clean attributes: {clean_attributes}")

        initial_shape = pyprt.InitialShape(flattened_coords, indices, face_counts)

        # Setup Model Generator
        export_options = {
            "outputPath": tempfile.mkdtemp(),
            "outputFilename": "model",
            "emitReport": True,
            "emitGeometry": True
        }

        is_geometry_only = request.rpk_name in GEOMETRY_ONLY_RPKS

        try:
            if is_geometry_only:
                # Geometry-only RPKs (e.g. translateModel) crash PyEncoder.
                # Skip report extraction entirely and always use empty attrs.
                reports_dict = {}
                model_generator = pyprt.ModelGenerator([initial_shape])
                model_generator.generate_model(
                    [{}],
                    rpk_path,
                    "com.esri.prt.codecs.GLTFEncoder",
                    export_options,
                )
            else:
                # Pass 1 – extract CGA reports via PyEncoder
                report_attrs = _ensure_report_attrs(request.rpk_name, clean_attributes)
                reports_dict = _extract_reports(initial_shape, report_attrs, rpk_path)

                # Pass 2 – generate the actual GLB geometry
                model_generator = pyprt.ModelGenerator([initial_shape])
                models = model_generator.generate_model(
                    [clean_attributes],
                    rpk_path,
                    "com.esri.prt.codecs.GLTFEncoder",
                    export_options,
                )

        except Exception as e:
            # Any PyPRT error (AttributeError, TypeError, RuntimeError…)
            # Retry with empty attrs so the CGA rule uses its defaults.
            logger.warning(
                f"PyPRT error with supplied attrs ({type(e).__name__}: {e}). "
                "Retrying with CGA defaults (empty attrs)."
            )
            try:
                reports_dict = {} if is_geometry_only else _extract_reports(
                    initial_shape,
                    _ensure_report_attrs(request.rpk_name, {}),
                    rpk_path,
                )
                model_generator = pyprt.ModelGenerator([initial_shape])
                model_generator.generate_model(
                    [{}],
                    rpk_path,
                    "com.esri.prt.codecs.GLTFEncoder",
                    export_options,
                )
            except Exception as e2:
                logger.error(f"PyPRT Generation Error (retry failed): {e2}")
                import traceback; traceback.print_exc()
                raise HTTPException(status_code=500, detail=f"PyPRT Generation Failed: {str(e2)}")

        output_path = export_options["outputPath"]
        
        # PyPRT GLTFEncoder usually spits out .glb by default, or .gltf
        generated_files = glob.glob(os.path.join(output_path, "*.glb"))
        if not generated_files:
            generated_files = glob.glob(os.path.join(output_path, "*.gltf"))
            
        if generated_files:
            glb_path = generated_files[0]
            logger.info(f"Found GLTF/GLB at {glb_path}")
            
            # Return JSONResponse where we provide the file download link and the reports
            # But the requirement from frontend is typically:
            # - if we want URL and reports together, we need a JSON response
            # - we can statically serve the generated file if it's placed in a static dir.
            # Right now, FileResponse is returned directly. 
            
            uuid_folder = str(uuid.uuid4())
            serve_dir = os.path.join(LAYERS_DIR, uuid_folder)
            os.makedirs(serve_dir, exist_ok=True)
            
            final_glb_path = os.path.join(serve_dir, "model.glb")
            shutil.copy(glb_path, final_glb_path)

            # Cleanup downloaded textures now that generation is done
            if tex_temp_dir and os.path.exists(tex_temp_dir):
                shutil.rmtree(tex_temp_dir, ignore_errors=True)

            return JSONResponse(content={
                "url": f"/layers/{uuid_folder}/model.glb",
                "reports": reports_dict,
                "message": "GLB Generated Natively"
            })

        else:
             logger.error(f"No GLB/GLTF file found in {output_path}")
             raise HTTPException(status_code=500, detail="PyPRT Generation failed: No GLB file created")

    except Exception as e:
        # Cleanup downloaded textures on error path too
        if 'tex_temp_dir' in locals() and tex_temp_dir and os.path.exists(tex_temp_dir):
            shutil.rmtree(tex_temp_dir, ignore_errors=True)
        logger.error(f"Generation error: {e}")
        raise HTTPException(status_code=500, detail=str(e))

@app.post("/generate_i3s")
async def generate_i3s(request: GenerateRequest):
    """Generate an I3S Layer (SLPK unpacked) using same logic as GLB generation."""
    
    # 0. Cleanup Old Layers
    try:
        if os.path.exists(LAYERS_DIR):
            for item in os.listdir(LAYERS_DIR):
                item_path = os.path.join(LAYERS_DIR, item)
                if os.path.isdir(item_path):
                    shutil.rmtree(item_path)
    except Exception as e:
        logger.warning(f"Cleanup failed: {e}")

    rpk_path = get_rpk_path(request.rpk_name)
    if not rpk_path:
        raise HTTPException(status_code=404, detail="RPK not found")

    try:
        # 1. Parse Geometry — extract ECEF center before stripping the Feature wrapper.
        #    geometry.properties.center = {x,y,z} ECEF Cartesian3 set by DrawTools.tsx.
        geom_dict = request.geometry
        ecef_center = None
        if geom_dict.get("type") == "Feature":
            props = geom_dict.get("properties") or {}
            c = props.get("center") or {}
            if c and "x" in c and "y" in c and "z" in c:
                ecef_center = (float(c["x"]), float(c["y"]), float(c["z"]))
            geom_dict = geom_dict.get("geometry")

        shape = shapely.geometry.shape(geom_dict)
        if geom_dict.get("type") != "Polygon":
            raise HTTPException(status_code=400, detail="Only Polygons are supported")

        if not shape.is_valid:
            shape = shape.buffer(0)

        # 2. ecef_center from Cesium is already EPSG:4978 (ECEF X/Y/Z in metres).
        #    Use it directly as globalOffset — no projection conversion needed.
        #    Vertices stay in ENU-local CGA format (small offsets, same as GLB).
        if not ecef_center:
            logger.warning("No ECEF center — I3S placed at Earth origin (incorrect)")
            ecef_center = (0.0, 0.0, 0.0)
        logger.info(f"I3S ECEF anchor: ({ecef_center[0]:.1f}, {ecef_center[1]:.1f}, {ecef_center[2]:.1f})")

        centroid = shape.centroid
        shape_centered = translate(shape, xoff=-centroid.x, yoff=-centroid.y)
        coords = list(shape_centered.exterior.coords)
        if coords[0] == coords[-1]:
            coords = coords[:-1]

        # ENU-local CGA vertices: X=east, Y=height=0, Z=-north (same as /generate GLB).
        # The encoder rotates these local axes to ECEF using globalOffset as the anchor.
        flattened_coords = []
        for p in coords:
            flattened_coords.extend([p[0], 0, -p[1]])

        indices = list(range(len(coords)))
        face_counts = [len(coords)]

        # Sanitise attributes
        clean_attributes = _clean_attributes(request.attributes)
        rpk_path, clean_attributes, tex_temp_dir = _inject_textures_into_rpk(rpk_path, clean_attributes)

        initial_shape = pyprt.InitialShape(flattened_coords, indices, face_counts)

        # 3. Encoder Options — Global scene, ECEF (EPSG:4978).
        #    sceneWkid 4978 is required for sceneType 'Global'.
        #    globalOffset = ECEF anchor; encoder rotates local CGA axes to ECEF at that point.
        layer_id = str(uuid.uuid4())
        output_dir = os.path.join(LAYERS_DIR, layer_id)
        os.makedirs(output_dir, exist_ok=True)

        slpk_name = f"SceneLayer_{layer_id[:8]}"
        enc_options = {
            'sceneType':               'Global',
            'sceneWkid':               '4978',
            # ECEF anchor — places the local CGA origin at the drawn polygon centroid
            'globalOffset':            list(ecef_center),
            'baseName':                slpk_name,
            'writePackage':            False,    # unzipped folder; fallback extracts .slpk if unsupported
            'layerTextureEncoding':    ['2'],
            'layerEnabled':            [True],
            'layerUID':                ['1'],
            'layerName':               ['1'],
            'layerTextureQuality':     [1.0],
            'layerTextureCompression': [9],
            'layerTextureScaling':     [1.0],
            'layerTextureMaxDimension':[2048],
            'layerFeatureGranularity': ['0'],
            'layerBackfaceCulling':    [False],
            'outputPath':              output_dir,
        }

        logger.info(f"Generating I3S (Global/ECEF 4978) to {output_dir}")

        # Pass 1 – extract CGA reports via PyEncoder
        # (I3SEncoder returns an empty list, so get_report() never fires)
        report_attrs = _ensure_report_attrs(request.rpk_name, clean_attributes)
        reports_dict = _extract_reports(initial_shape, report_attrs, rpk_path)

        # Pass 2 – generate the actual I3S scene layer
        model_generator = pyprt.ModelGenerator([initial_shape])
        models = model_generator.generate_model(
            [clean_attributes],
            rpk_path,
            'com.esri.prt.codecs.I3SEncoder',
            enc_options,
        )
        # (models is empty for file encoders — that is expected)

        # ── Decompress all .gz files written by the encoder ───────────────
        for _r, _d, _fs in os.walk(output_dir):
            for _f in _fs:
                if _f.endswith('.gz'):
                    _gz_path = os.path.join(_r, _f)
                    _out_path = _gz_path[:-3]
                    with gzip.open(_gz_path, 'rb') as _gzf, open(_out_path, 'wb') as _outf:
                        _outf.write(_gzf.read())
                    os.remove(_gz_path)

        _all_written = []
        for _r, _d, _fs in os.walk(output_dir):
            for _f in _fs:
                _all_written.append(os.path.relpath(os.path.join(_r, _f), output_dir).replace("\\", "/"))
        logger.info(f"I3S encoder (decompressed) {len(_all_written)} file(s): {_all_written[:40]}")
        # ───────────────────────────────────────────────────────────────────

        # Search for the I3S entry point (3dSceneLayer.json)
        json_file_path = None
        debug_files = list(_all_written)

        for root, dirs, files in os.walk(output_dir):
            for file in files:
                if file == "3dSceneLayer.json":
                    rel_from_layers = os.path.relpath(
                        os.path.join(root, file), LAYERS_DIR
                    ).replace("\\", "/")
                    json_file_path = f"/layers/{rel_from_layers}"

        if not json_file_path:
            # writePackage:False may be unsupported in this PyPRT build — the
            # encoder falls back to writing a .slpk ZIP.  Extract it so we can
            # serve the individual files via StaticFiles.
            slpk_files = glob.glob(os.path.join(output_dir, "*.slpk"))
            if slpk_files:
                extract_dir = os.path.join(output_dir, "extracted")
                os.makedirs(extract_dir, exist_ok=True)
                logger.info(f"Extracting SLPK: {slpk_files[0]} → {extract_dir}")
                with zipfile.ZipFile(slpk_files[0], "r") as zf:
                    zf.extractall(extract_dir)
                debug_files.clear()
                for root, dirs, files in os.walk(extract_dir):
                    for file in files:
                        rel_path = os.path.relpath(os.path.join(root, file), extract_dir)
                        debug_files.append("extracted/" + rel_path.replace("\\", "/"))
                        if file == "3dSceneLayer.json":
                            rel_from_layers = os.path.relpath(
                                os.path.join(root, file), LAYERS_DIR
                            ).replace("\\", "/")
                            json_file_path = f"/layers/{rel_from_layers}"
            if not json_file_path:
                logger.error(f"Could not find 3dSceneLayer.json in {output_dir}")
                raise HTTPException(status_code=500, detail="I3S generation produced no 3dSceneLayer.json")
        
        # Cleanup downloaded textures
        if tex_temp_dir and os.path.exists(tex_temp_dir):
            shutil.rmtree(tex_temp_dir, ignore_errors=True)

        return {
            "layerUrl": json_file_path,
            "layerId": layer_id,
            "reports": reports_dict,
            "message": "I3S Layer Generated",
            "debug_files": debug_files[:20] # Return first 20 files for debugging
        }

    except Exception as e:
        if 'tex_temp_dir' in locals() and tex_temp_dir and os.path.exists(tex_temp_dir):
            shutil.rmtree(tex_temp_dir, ignore_errors=True)
        logger.error(f"I3S Generation error: {e}")
        import traceback
        traceback.print_exc()
        raise HTTPException(status_code=500, detail=str(e))

@app.middleware("http")
async def i3s_smart_middleware(request: Request, call_next):
    # Intercept requests to /layers/
    if request.url.path.startswith("/layers"):
        path = request.url.path
        
        # Determine local path
        # URL: /layers/<uuid>/...
        # Local: .../static/layers/<uuid>/...
        rel_path = path[len("/layers"):]
        if rel_path.startswith("/"): rel_path = rel_path[1:]
        local_path = os.path.join(LAYERS_DIR, rel_path.replace("/", os.sep))
        
        # Logic to map REST-style I3S requests to File System
        target_file = None
        
        # 1. Check if exact file exists
        if os.path.isfile(local_path):
             pass # Let static handler take it
        else:
            # 2. Handle I3S Conventions
            
            # Case A: Layer Root (e.g. .../layers/0r or .../layers/0r/)
            # If directory exists, check for 3dSceneLayer.json
            if os.path.isdir(local_path):
                 possible_json = os.path.join(local_path, "3dSceneLayer.json")
                 if os.path.isfile(possible_json):
                      target_file = possible_json

            # Case B: Nodes (e.g. .../nodes/root or .../nodes/15)
            # Expects: .../nodes/root/3dNodeIndexDocument.json
            elif "/nodes/" in path:
                # Handle sub-resources of nodes
                clean_path = local_path.rstrip(os.sep)
                
                if "/geometries/" in path or "/attributes/" in path:
                    # .../geometries/0 -> .../geometries/0.bin
                    # .../attributes/f_0/0 -> .../attributes/f_0/0.bin
                    possible_bin = clean_path + ".bin"
                    if os.path.isfile(possible_bin):
                        target_file = possible_bin

                elif "/features/" in path or "/statistics/" in path or "/shared/" in path:
                    # .../features/0 -> .../features/0.json
                    # .../statistics/f_0/0 -> .../statistics/f_0/0.json
                    possible_json = clean_path + ".json"
                    if os.path.isfile(possible_json):
                        target_file = possible_json
                
                elif "/textures/" in path:
                     # Textures are tricky, often .jpg or .bin.dds
                     # Just try appending extensions
                     for ext in [".jpg", ".png", ".bin.dds", ".dds"]:
                         possible_tex = clean_path + ext
                         if os.path.isfile(possible_tex):
                             target_file = possible_tex
                             break

                else:
                    # It is a Node itself (e.g. .../nodes/1)
                    # If directory, look for 3dNodeIndexDocument.json
                    if os.path.isdir(clean_path):
                         possible_doc = os.path.join(clean_path, "3dNodeIndexDocument.json")
                         if os.path.isfile(possible_doc):
                              target_file = possible_doc

            # Case C: NodePages (e.g. .../nodepages/0 or .../nodepages/0/)
            # Expects: .../nodepages/0.json
            elif "/nodepages/" in path:
                 # Strip trailing slash if present to cleanly append .json
                 clean_local_path = local_path.rstrip(os.sep)
                     
                 # Check if adding .json helps
                 possible_json_page = clean_local_path + ".json"
                 if os.path.isfile(possible_json_page):
                      target_file = possible_json_page

        if target_file:
            logger.info(f"Serving I3S Resource: {path} -> {target_file}")
            ext = os.path.splitext(target_file)[1].lower()
            if ext == ".bin":
                mt = "application/octet-stream"
            elif ext in (".jpg", ".jpeg"):
                mt = "image/jpeg"
            elif ext == ".png":
                mt = "image/png"
            elif ext == ".dds":
                mt = "application/octet-stream"
            else:
                mt = "application/json"
            return FileResponse(target_file, media_type=mt)
            
    response = await call_next(request)
    return response

@app.get("/")
async def root():
    return {"message": "CityPyPRT 3D Generation API"}


# ---------------------------------------------------------------------------
# Dedicated report endpoint
# ---------------------------------------------------------------------------

@app.post("/report")
async def get_model_report(request: GenerateRequest):
    """
    Return **only** the CGA report dict for a given geometry + RPK, without
    writing any geometry files to disk.

    This uses ``com.esri.pyprt.PyEncoder`` with ``emitReport=True`` and
    ``emitGeometry=False`` — the only encoder that populates
    ``GeneratedModel.get_report()``.

    Request body (same as /generate)
    ---------------------------------
    .. code-block:: json

        {
          "rpk_name": "Building.rpk",
          "geometry": { "type": "Polygon", "coordinates": [...] },
          "attributes": { "buildingHeight": 30.0 }
        }

    Response
    --------
    .. code-block:: json

        {
          "report": { "Ground Floor Area": 250.0, "Building Volume": 3200.0 },
          "rpk_name": "Building.rpk"
        }
    """
    rpk_path = get_rpk_path(request.rpk_name)
    if not rpk_path:
        raise HTTPException(status_code=404, detail=f"RPK '{request.rpk_name}' not found")

    try:
        # --- Parse geometry (same logic as /generate) ---
        geom_dict = request.geometry
        if geom_dict.get("type") == "Feature":
            geom_dict = geom_dict.get("geometry")

        if geom_dict.get("type") != "Polygon":
            raise HTTPException(status_code=400, detail="Only Polygon geometries are supported")

        shape = shapely.geometry.shape(geom_dict)
        if not shape.is_valid:
            shape = shape.buffer(0)
        shape = shapely.ops.orient(shape, sign=-1.0)  # CW, consistent with /generate

        centroid = shape.centroid
        shape_centered = translate(shape, xoff=-centroid.x, yoff=-centroid.y)

        coords = list(shape_centered.exterior.coords)
        if coords[0] == coords[-1]:
            coords = coords[:-1]

        # Same CGA Z-axis negation as /generate: ENU Y = north, CGA Z = south
        flattened_coords = []
        for p in coords:
            flattened_coords.extend([p[0], 0, -p[1]])

        indices = list(range(len(coords)))
        face_counts = [len(coords)]

        # --- Sanitise attributes ---
        clean_attributes = _clean_attributes(request.attributes)
        # Inject any Material-API textures into a temp RPK copy so CGA resolves them
        rpk_path, clean_attributes, tex_temp_dir = _inject_textures_into_rpk(rpk_path, clean_attributes)
        initial_shape = pyprt.InitialShape(flattened_coords, indices, face_counts)

        # --- Run PyEncoder report pass ---
        try:
            report_attrs = _ensure_report_attrs(request.rpk_name, clean_attributes)
            reports_dict = _extract_reports(initial_shape, report_attrs, rpk_path)
        except (AttributeError, TypeError) as e:
            logger.warning(
                f"Report endpoint: attribute error with supplied attrs ({e}). "
                "Retrying with CGA defaults."
            )
            reports_dict = _extract_reports(initial_shape, _ensure_report_attrs(request.rpk_name, {}), rpk_path)

        if tex_temp_dir and os.path.exists(tex_temp_dir):
            shutil.rmtree(tex_temp_dir, ignore_errors=True)

        return JSONResponse(content={
            "report": reports_dict,
            "rpk_name": request.rpk_name,
        })

    except HTTPException:
        raise
    except Exception as exc:
        if 'tex_temp_dir' in locals() and tex_temp_dir and os.path.exists(tex_temp_dir):
            shutil.rmtree(tex_temp_dir, ignore_errors=True)
        logger.error(f"Report endpoint error: {exc}")
        import traceback
        traceback.print_exc()
        raise HTTPException(status_code=500, detail=str(exc))