import os
import re
import sys
import shutil
import subprocess
from pathlib import Path
from typing import List, Optional
import importlib.util

import requests
from fastapi import FastAPI, HTTPException
from fastapi.responses import FileResponse
from pydantic import BaseModel, HttpUrl, Field

# ----------------------------------------------------------------------------- #
# 🔧 환경 고정: libgomp 경고/에러 회피 (invalid OMP_NUM_THREADS)
# ----------------------------------------------------------------------------- #
# 일부 컨테이너에서 OMP_NUM_THREADS가 비어있거나 잘못 들어가면 libgomp가 에러를 냅니다.
# 안전하게 정수값으로 강제 세팅합니다.
os.environ["OMP_NUM_THREADS"] = os.environ.get("OMP_NUM_THREADS", "4")
if not os.environ["OMP_NUM_THREADS"].isdigit():
    os.environ["OMP_NUM_THREADS"] = "4"

# ----------------------------------------------------------------------------- #
# 🔧 런타임 의존성 자동 설치 (tqdm, einops, scipy, trimesh 등)
#  - requirements/Dockerfile에 빠진 경우를 대비해, 서버 기동 시 한 번 체크해서 설치
# ----------------------------------------------------------------------------- #
RUNTIME_DEPS = [
    "tqdm",
    "einops",
    "scipy",
    "trimesh",
    "accelerate",   # 추가
    "timm",         # 추가
    # 아래는 여유 패키지 (에러 나면 자동 보강)
    "networkx",
    "scikit-image",
]

def _need_install(mod_name: str) -> bool:
    return importlib.util.find_spec(mod_name) is None

def _pip_install(pkgs: List[str]) -> None:
    if not pkgs:
        return
    try:
        subprocess.check_call([sys.executable, "-m", "pip", "install", *pkgs])
    except Exception as e:
        print(f"[deps] pip install failed for {pkgs}: {e}")

def _ensure_runtime_deps() -> None:
    # numpy 2.x면 scipy 등과 충돌 가능 → numpy<2로 내리는 시도
    try:
        import numpy as _np
        if _np.__version__.startswith("2"):
            print(f"[deps] numpy=={_np.__version__} detected; attempting to pin <2.0")
            _pip_install(["numpy<2"])
    except Exception as e:
        print(f"[deps] numpy check failed: {e}")
    # 필수 모듈 채우기
    missing = [m for m in RUNTIME_DEPS if _need_install(m)]
    if missing:
        print(f"[deps] installing missing modules: {missing}")
        _pip_install(missing)
    # 최종 확인 로그
    for m in RUNTIME_DEPS:
        print(f"[deps] {m} -> {'OK' if not _need_install(m) else 'MISSING'}")

_ensure_runtime_deps()

# ----------------------------------------------------------------------------- #
# FastAPI 초기화
# ----------------------------------------------------------------------------- #
app = FastAPI(title="Puppeteer API", version="1.0.0")

# ----------------------------------------------------------------------------- #
# Settings
# ----------------------------------------------------------------------------- #
PUPPETEER_SRC = Path(os.environ.get("PUPPETEER_DIR", "/app/Puppeteer"))         # 읽기 전용 원본
PUPPETEER_RUN = Path(os.environ.get("PUPPETEER_RUN", "/tmp/puppeteer_run"))     # 실행용 복사본(쓰기 가능)
RESULT_DIR = Path(os.environ.get("RESULT_DIR", str(PUPPETEER_RUN / "results")))  # rig 결과 기본 경로
TMP_IN_DIR = Path(os.environ.get("TMP_IN_DIR", "/tmp/in"))                       # 입력 저장 경로
DOWNLOAD_TIMEOUT = int(os.environ.get("DOWNLOAD_TIMEOUT", "180"))
MAX_DOWNLOAD_MB = int(os.environ.get("MAX_DOWNLOAD_MB", "512"))
SAFE_NAME = re.compile(r"[^A-Za-z0-9._-]+")
# 애니메이션/리깅 결과를 폭넓게 찾기 위한 후보 경로
RESULT_BASES = [
    Path("/app/Puppeteer/results"),
    RESULT_DIR,
    Path("/data/results"),
    Path("/tmp/puppeteer_run/results"),
]

# ----------------------------------------------------------------------------- #
# Auto-download checkpoints (런타임 시 자동 다운로드)
# ----------------------------------------------------------------------------- #
ckpt_path = Path("/app/Puppeteer/checkpoints")
if not ckpt_path.exists() or not any(ckpt_path.iterdir()):
    try:
        print("[init] checkpoints missing — trying runtime download via script...")
        subprocess.run(
            ["bash", "-lc", "cd /app/Puppeteer && ./scripts/download_ckpt.sh"],
            check=True,
            stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT,
            text=True,
        )
        print("[init] Puppeteer checkpoints downloaded successfully via script.")
    except Exception as e:
        print("[init] WARNING: checkpoint script failed:", e)
        try:
            ckpt_path.mkdir(parents=True, exist_ok=True)
            print("[init] trying manual download from GitHub release...")
            subprocess.run(
                [
                    "wget",
                    "-O",
                    "/app/Puppeteer/checkpoints/rig.ckpt",
                    "https://github.com/ByteDance-Seed/Puppeteer/releases/download/v1.0.0/rig.ckpt",
                ],
                check=True,
            )
            print("[init] rig.ckpt downloaded manually.")
        except Exception as e2:
            print("[init] WARNING: manual checkpoint download failed:", e2)

# ----------------------------------------------------------------------------- #
# Schemas
# ----------------------------------------------------------------------------- #
class RigIn(BaseModel):
    mesh_url: HttpUrl = Field(..., description="Input mesh URL (obj/glb/fbx/…)")
    workdir: Optional[str] = Field(default=None, description="Optional work directory name")

class RigOut(BaseModel):
    status: str
    result_dir: Optional[str] = None
    files_preview: Optional[List[str]] = None
    detail: Optional[str] = None
    gpu: Optional[bool] = None
    gpu_name: Optional[str] = None

class AnimateIn(BaseModel):
    video_url: HttpUrl = Field(..., description="Input video URL (mp4, mov, etc.)")
    mesh_path: Optional[str] = Field(
        default="/app/Puppeteer/results/rigged.glb",
        description="Path to rigged mesh"
    )

# ----------------------------------------------------------------------------- #
# Utils
# ----------------------------------------------------------------------------- #
def ensure_dirs() -> None:
    TMP_IN_DIR.mkdir(parents=True, exist_ok=True)
    PUPPETEER_RUN.mkdir(parents=True, exist_ok=True)
    RESULT_DIR.mkdir(parents=True, exist_ok=True)

def prepare_run_tree() -> None:
    if not PUPPETEER_SRC.exists():
        raise HTTPException(status_code=500, detail=f"Puppeteer not found: {PUPPETEER_SRC}")
    shutil.copytree(PUPPETEER_SRC, PUPPETEER_RUN, dirs_exist_ok=True)
    script = PUPPETEER_RUN / "demo_rigging.sh"
    if script.exists():
        script.chmod(0o755)

def safe_basename(url: str) -> str:
    name = os.path.basename(url.split("?")[0])
    return SAFE_NAME.sub("_", name) or "input_mesh"

def download_with_limit(url: str, dst: Path) -> None:
    with requests.get(url, stream=True, timeout=DOWNLOAD_TIMEOUT) as r:
        r.raise_for_status()
        total = 0
        with open(dst, "wb") as f:
            for chunk in r.iter_content(chunk_size=1024 * 1024):
                if not chunk:
                    continue
                total += len(chunk)
                if total > MAX_DOWNLOAD_MB * 1024 * 1024:
                    raise HTTPException(status_code=413, detail="File too large")
                f.write(chunk)

def torch_info() -> tuple[bool, Optional[str]]:
    try:
        import torch
        ok = torch.cuda.is_available()
        name = torch.cuda.get_device_name(0) if ok else None
        return ok, name
    except Exception:
        return False, None

def scan_results(limit: int = 200) -> List[str]:
    files: List[str] = []
    exts = ("*.glb", "*.mp4", "*.fbx", "*.obj", "*.gltf", "*.png", "*.jpg", "*.json", "*.txt")
    for base in RESULT_BASES:
        if base.exists():
            for ext in exts:
                for p in base.rglob(ext):
                    if p.is_file():
                        files.append(str(p))
                        if len(files) >= limit:
                            return files
    return files

# ----------------------------------------------------------------------------- #
# Routes
# ----------------------------------------------------------------------------- #
@app.get("/")
def root():
    return {"status": "ready", "service": "puppeteer-api"}

@app.get("/health")
def health():
    gpu, name = torch_info()
    return {"status": "ok", "cuda": gpu, "gpu": name}

@app.post("/rig", response_model=RigOut)
def rig(inp: RigIn):
    ensure_dirs()
    prepare_run_tree()

    basename = safe_basename(str(inp.mesh_url))
    mesh_path = TMP_IN_DIR / basename
    _ = SAFE_NAME.sub("_", inp.workdir or "job")  # reserved, 현재는 미사용

    try:
        download_with_limit(str(inp.mesh_url), mesh_path)
    except Exception as e:
        raise HTTPException(status_code=400, detail=f"Download error: {e}")

    script = PUPPETEER_RUN / "demo_rigging.sh"
    cmd = ["bash", str(script), str(mesh_path)]
    try:
        proc = subprocess.run(
            cmd,
            cwd=str(PUPPETEER_RUN),
            check=True,
            stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT,
            text=True,
        )
        run_log = proc.stdout[-4000:]
    except subprocess.CalledProcessError as e:
        snippet = (e.stdout or "")[-2000:]
        raise HTTPException(status_code=500, detail=f"Puppeteer failed: {snippet}")
    except FileNotFoundError:
        raise HTTPException(status_code=500, detail="demo_rigging.sh not found")

    preview = scan_results(limit=20)
    gpu, gpu_name = torch_info()
    return RigOut(
        status="ok",
        result_dir=str(RESULT_DIR),
        files_preview=preview[:10],
        detail=run_log if preview else "no result files found",
        gpu=gpu,
        gpu_name=gpu_name,
    )

@app.post("/animate")
def animate(inp: AnimateIn):
    """
    Puppeteer의 demo_animation.sh 실행 (영상 기반 애니메이션)
    입력: video_url (mp4), mesh_path (rigged.glb 기본값)
    """
    pdir = Path("/app/Puppeteer")
    script = pdir / "demo_animation.sh"
    video_path = Path("/tmp/video.mp4")

    if not script.exists():
        raise HTTPException(status_code=404, detail="demo_animation.sh not found")

    # -------- requests 기반 영상 다운로드 -------- #
    try:
        print(f"[animate] downloading video from {inp.video_url}")
        with requests.get(str(inp.video_url), stream=True, timeout=60) as r:
            r.raise_for_status()
            with open(video_path, "wb") as f:
                for chunk in r.iter_content(chunk_size=8192):
                    if chunk:
                        f.write(chunk)
        print(f"[animate] Video saved to {video_path}")
    except Exception as e:
        raise HTTPException(status_code=400, detail=f"Video download failed via requests: {e}")

    # -------- Puppeteer 애니메이션 실행 -------- #
    cmd = [
        "bash", str(script),
        "--mesh", str(inp.mesh_path),
        "--video", str(video_path),
    ]
    try:
        proc = subprocess.run(
            cmd,
            cwd=str(pdir),
            check=True,
            stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT,
            text=True,
        )
        output = proc.stdout[-4000:]
    except subprocess.CalledProcessError as e:
        raise HTTPException(status_code=500, detail=f"Animation failed: {e.stdout[-2000:]}")
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Unexpected error: {e}")

    anim_results = scan_results(limit=20)
    return {
        "status": "ok",
        "video_used": str(inp.video_url),
        "detail": output,
        "files_preview": anim_results[:10],
    }

# -------- 결과 파일 확인/다운로드 유틸 -------- #
@app.get("/list")
def list_results():
    files = scan_results(limit=500)
    return {"count": len(files), "files": files}

@app.get("/download")
def download(path: str):
    p = Path(path).resolve()
    # 안전한 경로만 허용
    if not any(str(p).startswith(str(b.resolve())) for b in RESULT_BASES):
        raise HTTPException(status_code=400, detail="invalid path")
    if not p.exists() or not p.is_file():
        raise HTTPException(status_code=404, detail="file not found")
    return FileResponse(str(p), filename=p.name)

@app.get("/debug")
def debug():
    pdir = Path("/app/Puppeteer")
    script = pdir / "demo_rigging.sh"
    ckpt_dir = pdir / "checkpoints"
    req_file = pdir / "requirements.txt"
    return {
        "script_exists": script.exists(),
        "ckpt_dir_exists": ckpt_dir.exists(),
        "req_exists": req_file.exists(),
        "ckpt_samples": [str(p) for p in ckpt_dir.glob("**/*")][:15],
        "tmp_in": os.environ.get("TMP_IN_DIR", "/data/in"),
        "result_dir": os.environ.get("RESULT_DIR", "/data/results"),
        "omp_num_threads": os.environ.get("OMP_NUM_THREADS"),
    }