"""Asset Libraries API — CRUD + .blend upload + catalog refresh."""
import uuid
import shutil
from pathlib import Path

from fastapi import APIRouter, Depends, HTTPException, UploadFile, File, Form, status
from fastapi.responses import JSONResponse
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select
from pydantic import BaseModel

from app.database import get_db
from sqlalchemy import text
from app.config import settings
from app.domains.materials.models import AssetLibrary, Material, MaterialAlias
from app.utils.auth import require_admin_or_pm

router = APIRouter(prefix="/asset-libraries", tags=["asset-libraries"])

ASSET_LIB_DIR = "asset-libraries"


def _asset_lib_dir() -> Path:
    d = Path(settings.upload_dir) / ASSET_LIB_DIR
    d.mkdir(parents=True, exist_ok=True)
    return d


# ── Schemas ──────────────────────────────────────────────────────────────────

class AssetLibraryOut(BaseModel):
    id: str
    name: str
    description: str | None
    original_filename: str | None
    catalog: dict
    is_active: bool
    created_at: str
    updated_at: str


class AssetLibraryUpdate(BaseModel):
    name: str | None = None
    description: str | None = None
    is_active: bool | None = None


def _to_out(lib: AssetLibrary) -> dict:
    return {
        "id": str(lib.id),
        "name": lib.name,
        "description": lib.description,
        "original_filename": lib.original_filename,
        "catalog": lib.catalog or {"materials": [], "node_groups": []},
        "is_active": lib.is_active,
        "created_at": lib.created_at.isoformat(),
        "updated_at": lib.updated_at.isoformat(),
    }


# ── Endpoints ─────────────────────────────────────────────────────────────────

@router.get("/pbr-map")
async def get_material_pbr_map(db: AsyncSession = Depends(get_db)):
    """PBR properties for all materials in the active asset library.

    Public (no auth) — needed by all 3D viewers.
    Returns keyed by canonical name AND all known aliases so the viewer can
    look up materials by raw Excel names (e.g. "Steel--Stahl") without needing
    a separate alias resolution step.
    """
    result = await db.execute(
        select(AssetLibrary).where(AssetLibrary.is_active == True).limit(1)  # noqa: E712
    )
    lib = result.scalar_one_or_none()
    if not lib or not lib.catalog:
        return JSONResponse(content={}, headers={"Cache-Control": "public, max-age=3600"})
    materials = lib.catalog.get("materials", [])
    pbr_map: dict = {}
    for m in materials:
        if isinstance(m, str):
            continue  # old format — skip
        pbr_map[m["name"]] = {
            "base_color": m.get("base_color", [0.5, 0.5, 0.5]),
            "metallic": m.get("metallic", 0.0),
            "roughness": m.get("roughness", 0.5),
            "transmission": m.get("transmission", 0.0),
            "ior": m.get("ior", 1.45),
        }

    # Also index by aliases so frontend can look up by raw Excel names
    # (e.g. "Steel--Stahl" → same PBR as "SCHAEFFLER_010101_Steel-Bare")
    # Bypass RLS — this is public data and aliases may have NULL tenant_id
    if pbr_map:
        await db.execute(text("SET LOCAL app.current_tenant_id = 'bypass'"))
        alias_result = await db.execute(
            select(MaterialAlias.alias, Material.name)
            .join(Material, MaterialAlias.material_id == Material.id)
        )
        for alias, canonical_name in alias_result.all():
            if canonical_name in pbr_map and alias not in pbr_map:
                pbr_map[alias] = pbr_map[canonical_name]

    return JSONResponse(content=pbr_map, headers={"Cache-Control": "public, max-age=3600"})


@router.get("", response_model=list[AssetLibraryOut])
async def list_asset_libraries(
    db: AsyncSession = Depends(get_db),
    _user=Depends(require_admin_or_pm),
):
    result = await db.execute(select(AssetLibrary).order_by(AssetLibrary.name))
    return [_to_out(lib) for lib in result.scalars().all()]


@router.post("", response_model=AssetLibraryOut, status_code=status.HTTP_201_CREATED)
async def create_asset_library(
    name: str = Form(...),
    description: str | None = Form(None),
    blend_file: UploadFile = File(...),
    db: AsyncSession = Depends(get_db),
    _user=Depends(require_admin_or_pm),
):
    lib = AssetLibrary(
        name=name,
        description=description,
        original_filename=blend_file.filename,
        catalog={"materials": [], "node_groups": []},
    )
    db.add(lib)
    await db.flush()  # get the id

    # Save .blend file
    dest = _asset_lib_dir() / f"{lib.id}.blend"
    with dest.open("wb") as f:
        shutil.copyfileobj(blend_file.file, f)
    lib.blend_file_path = str(dest)

    await db.commit()
    await db.refresh(lib)

    # Queue catalog refresh
    try:
        from app.domains.materials.tasks import refresh_asset_library_catalog
        refresh_asset_library_catalog.delay(str(lib.id))
    except Exception:
        pass  # task queuing failure is non-blocking

    return _to_out(lib)


@router.get("/{lib_id}", response_model=AssetLibraryOut)
async def get_asset_library(
    lib_id: uuid.UUID,
    db: AsyncSession = Depends(get_db),
    _user=Depends(require_admin_or_pm),
):
    lib = await db.get(AssetLibrary, lib_id)
    if not lib:
        raise HTTPException(status_code=404, detail="Asset library not found")
    return _to_out(lib)


@router.patch("/{lib_id}", response_model=AssetLibraryOut)
async def update_asset_library(
    lib_id: uuid.UUID,
    body: AssetLibraryUpdate,
    db: AsyncSession = Depends(get_db),
    _user=Depends(require_admin_or_pm),
):
    lib = await db.get(AssetLibrary, lib_id)
    if not lib:
        raise HTTPException(status_code=404, detail="Asset library not found")
    for field, value in body.model_dump(exclude_none=True).items():
        setattr(lib, field, value)
    await db.commit()
    await db.refresh(lib)
    return _to_out(lib)


@router.post("/{lib_id}/upload-blend", response_model=AssetLibraryOut)
async def upload_blend(
    lib_id: uuid.UUID,
    blend_file: UploadFile = File(...),
    db: AsyncSession = Depends(get_db),
    _user=Depends(require_admin_or_pm),
):
    lib = await db.get(AssetLibrary, lib_id)
    if not lib:
        raise HTTPException(status_code=404, detail="Asset library not found")

    dest = _asset_lib_dir() / f"{lib.id}.blend"
    with dest.open("wb") as f:
        shutil.copyfileobj(blend_file.file, f)
    lib.blend_file_path = str(dest)
    lib.original_filename = blend_file.filename

    await db.commit()
    await db.refresh(lib)

    try:
        from app.domains.materials.tasks import refresh_asset_library_catalog
        refresh_asset_library_catalog.delay(str(lib.id))
    except Exception:
        pass

    return _to_out(lib)


@router.post("/{lib_id}/refresh-catalog", response_model=AssetLibraryOut)
async def refresh_catalog(
    lib_id: uuid.UUID,
    db: AsyncSession = Depends(get_db),
    _user=Depends(require_admin_or_pm),
):
    lib = await db.get(AssetLibrary, lib_id)
    if not lib:
        raise HTTPException(status_code=404, detail="Asset library not found")
    if not lib.blend_file_path:
        raise HTTPException(status_code=400, detail="No .blend file uploaded yet")

    from app.domains.materials.tasks import refresh_asset_library_catalog
    refresh_asset_library_catalog.delay(str(lib.id))
    return _to_out(lib)


@router.delete("/{lib_id}", status_code=status.HTTP_204_NO_CONTENT)
async def delete_asset_library(
    lib_id: uuid.UUID,
    db: AsyncSession = Depends(get_db),
    _user=Depends(require_admin_or_pm),
):
    lib = await db.get(AssetLibrary, lib_id)
    if not lib:
        raise HTTPException(status_code=404, detail="Asset library not found")

    # Remove .blend file from disk
    if lib.blend_file_path:
        p = Path(lib.blend_file_path)
        if p.exists():
            p.unlink()

    await db.delete(lib)
    await db.commit()