# HuggingFace Spaces Dockerfile — CPU-only, port 7860
# Follows HF recommended pattern: USER user before pip installs (no chown needed)
FROM python:3.10-slim

# ── System dependencies (run as root) ─────────────────────────────────────────
RUN apt-get update && apt-get install -y --no-install-recommends \
    ffmpeg \
    tesseract-ocr \
    tesseract-ocr-eng \
    libsndfile1 \
    poppler-utils \
    libgomp1 \
    libglib2.0-0 \
    libsm6 \
    libxext6 \
    libxrender1 \
    build-essential \
    python3-dev \
    git \
    curl \
    && rm -rf /var/lib/apt/lists/*

# ── Create non-root user required by HuggingFace Spaces (UID 1000) ────────────
RUN useradd -m -u 1000 user

# ── Switch to non-root user for ALL subsequent steps ──────────────────────────
# This is HF's recommended pattern — installs go to ~/.local, no chown needed
USER user

# ── Environment variables ──────────────────────────────────────────────────────
ENV HOME=/home/user \
    PATH=/home/user/.local/bin:$PATH \
    PYTHONUNBUFFERED=1 \
    PYTHONDONTWRITEBYTECODE=1 \
    TRANSFORMERS_CACHE=/home/user/.cache/huggingface \
    HF_HOME=/home/user/.cache/huggingface \
    TORCH_HOME=/home/user/.cache/torch \
    NLTK_DATA=/home/user/nltk_data \
    API_PORT=7860 \
    API_HOST=0.0.0.0 \
    ENABLE_GPU=false \
    ENABLE_REDIS=false \
    DEFAULT_WHISPER_MODEL=base \
    ENABLE_QUALITY_ASSESSMENT=false \
    ENABLE_BACKTRANSLATION_CHECK=false \
    ENABLE_ENSEMBLE=false \
    MAX_WORKERS=1 \
    BATCH_SIZE=8 \
    ENVIRONMENT=production \
    CORS_ORIGINS='["*"]' \
    LOG_LEVEL=INFO

# ── Working directory ──────────────────────────────────────────────────────────
WORKDIR /home/user/app

# ── Upgrade pip and build tools ────────────────────────────────────────────────
RUN pip install --no-cache-dir --upgrade pip setuptools wheel

# ── Install CPU-only PyTorch (separate layer for caching) ─────────────────────
RUN pip install --no-cache-dir \
    torch==2.1.1+cpu \
    torchaudio==2.1.1+cpu \
    --index-url https://download.pytorch.org/whl/cpu

# ── Install app dependencies ───────────────────────────────────────────────────
# requirements.txt is renamed from requirements.spaces.txt by deploy_hf.sh
#
# --no-build-isolation: pip normally creates an isolated sandbox to build source
# distributions (packages with no pre-built wheel, like openai-whisper and
# sacremoses). That sandbox does NOT inherit our installed setuptools, so
# pkg_resources is missing and the build fails. This flag tells pip to build
# packages using the current environment where setuptools is already present.
COPY --chown=user:user requirements.txt .
RUN pip install --no-cache-dir --no-build-isolation -r requirements.txt

# ── Create runtime directories ─────────────────────────────────────────────────
RUN mkdir -p \
    /home/user/app/uploads \
    /home/user/app/temp \
    /home/user/app/cache \
    /home/user/app/logs \
    /home/user/app/models \
    /home/user/.cache/huggingface \
    /home/user/.cache/torch \
    /home/user/.cache/whisper \
    /home/user/nltk_data

# ── NLTK data (~3 MB, safe at build time) ─────────────────────────────────────
RUN python -c "\
import nltk; \
nltk.download('punkt',     download_dir='/home/user/nltk_data', quiet=True); \
nltk.download('punkt_tab', download_dir='/home/user/nltk_data', quiet=True); \
nltk.download('stopwords', download_dir='/home/user/nltk_data', quiet=True)"

# ── NOTE: ML models (NLLB-200 ~2.5 GB, Whisper base ~150 MB) are NOT downloaded
# here because the Docker BUILD environment has limited RAM and OOMKills on model
# loading. Models are downloaded automatically on first startup by the app's
# lifespan handler (main.py) in the RUNNING container which has 16 GB RAM.

# ── Copy application code ──────────────────────────────────────────────────────
COPY --chown=user:user . .
RUN rm -f .env .env.spaces* 2>/dev/null || true

# ── Expose HF Spaces port ──────────────────────────────────────────────────────
EXPOSE 7860

HEALTHCHECK --interval=30s --timeout=15s --start-period=120s --retries=3 \
    CMD curl -f http://localhost:7860/health || exit 1

CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "7860", "--workers", "1"]