#!/usr/bin/env bash
set -euo pipefail

ROOT_DIR="$(cd "$(dirname "$0")" && pwd)"
VENV_DIR="$ROOT_DIR/.venv"
BACKEND_PORT="${BACKEND_PORT:-8000}"

# ── find python ──────────────────────────────────────────
PYTHON=""
for cmd in python3.13 python3.12 python3.11 python3.10 python3.9 python3; do
    if command -v "$cmd" >/dev/null 2>&1; then
        PYTHON="$cmd"
        break
    fi
done
[[ -n "$PYTHON" ]] || { echo "[ERROR] 找不到 python3"; exit 1; }

# verify version >= 3.9
if ! "$PYTHON" -c 'import sys; raise SystemExit(0 if sys.version_info >= (3,9) else 1)'; then
    echo "[ERROR] 需要 Python 3.9+"; exit 1
fi

# ── deps check & install ─────────────────────────────────
DEPS_OK=0
if "$PYTHON" -c "
import importlib.util, sys
mods = ('fastapi','uvicorn','pandas','PIL','numpy','matplotlib','pydantic','openpyxl')
for m in mods:
    if importlib.util.find_spec(m) is None:
        sys.exit(1)
" 2>/dev/null; then
    DEPS_OK=1
fi

if [[ "$DEPS_OK" == "0" ]]; then
    # try venv first
    if [[ -f "$VENV_DIR/bin/python" ]] && "$VENV_DIR/bin/python" --version >/dev/null 2>&1; then
        PYTHON="$VENV_DIR/bin/python"
        if "$PYTHON" -c "
import importlib.util, sys
for m in ('fastapi','uvicorn','pandas','PIL','numpy','matplotlib','pydantic','openpyxl'):
    if importlib.util.find_spec(m) is None: sys.exit(1)
" 2>/dev/null; then
            DEPS_OK=1
        fi
    fi
fi

if [[ "$DEPS_OK" == "0" ]]; then
    echo "[INFO]  安装依赖 (首次或缺失) ..."
    # create venv if needed
    if [[ ! -f "$VENV_DIR/bin/python" ]]; then
        "$PYTHON" -m venv "$VENV_DIR"
    fi
    PYTHON="$VENV_DIR/bin/python"
    "$PYTHON" -m pip install -q --upgrade pip
    "$PYTHON" -m pip install -q fastapi uvicorn python-multipart pydantic pandas openpyxl pillow numpy matplotlib
fi

# SciPy is an optional accelerator for line-spacing analysis. The production
# requirements include it, but local dev environments may already have it in
# the base interpreter while the project venv does not. Reuse that copy when
# the Python ABI matches so startup does not require a network install.
EXTRA_SCIPY_SITE=""
if ! "$PYTHON" -c 'import scipy' >/dev/null 2>&1; then
    PYTHON_ABI=$("$PYTHON" -c 'import sys; print(f"{sys.version_info.major}.{sys.version_info.minor}")')
    for cmd in python3.13 python3.12 python3.11 python3.10 python3.9 python3; do
        if command -v "$cmd" >/dev/null 2>&1; then
            SCIPY_SITE=$("$cmd" -c '
import pathlib
import scipy
import sys
expected = "'"$PYTHON_ABI"'"
current = f"{sys.version_info.major}.{sys.version_info.minor}"
print(pathlib.Path(scipy.__file__).parents[1] if current == expected else "")
' 2>/dev/null || true)
            if [[ -n "$SCIPY_SITE" ]]; then
                EXTRA_SCIPY_SITE="$SCIPY_SITE"
                echo "[OK]    使用外部 SciPy 加速线距计算: $SCIPY_SITE"
                break
            fi
        fi
    done
fi

# ── C++ extension ────────────────────────────────────────
EXT=$($PYTHON -c 'import importlib.machinery; print(importlib.machinery.EXTENSION_SUFFIXES[0])')
EWC_SO="$ROOT_DIR/EfficientWordCloud/efficient_wordcloud/ewc_core${EXT}"
EWC_CPP="$ROOT_DIR/EfficientWordCloud/efficient_wordcloud/src/ewc_core.cpp"

if [[ ! -f "$EWC_SO" ]] || [[ "$EWC_CPP" -nt "$EWC_SO" ]]; then
    echo "[INFO]  编译 ewc_core ..."
    (cd "$ROOT_DIR/EfficientWordCloud" && "$PYTHON" setup.py build_ext --inplace >/dev/null)
    echo "[OK]    编译完成"
else
    echo "[OK]    ewc_core 就绪"
fi

# ── ensure runtime dirs ──────────────────────────────────
mkdir -p "$ROOT_DIR/service_workspace" "$ROOT_DIR/service_assets" "$ROOT_DIR/service_projects"

# ── port: auto-kill occupant ─────────────────────────────
if ss -tln 2>/dev/null | grep -q ":$BACKEND_PORT "; then
    echo "[INFO]  端口 $BACKEND_PORT 被占用，正在释放 ..."
    fuser -k "$BACKEND_PORT/tcp" >/dev/null 2>&1 || true
    sleep 1
fi

# ── start ────────────────────────────────────────────────
echo "[INFO]  启动后端 http://0.0.0.0:${BACKEND_PORT}"

WORDCLOUD_SCIPY_SITE="$EXTRA_SCIPY_SITE" \
PYTHONPATH="$ROOT_DIR/EfficientWordCloud" \
    "$PYTHON" -m uvicorn service.app:app \
    --app-dir "$ROOT_DIR" \
    --host 0.0.0.0 --port "$BACKEND_PORT" \
    --reload &
PID=$!

echo "[OK]    PID: $PID"
echo "[OK]    API: http://0.0.0.0:${BACKEND_PORT}/docs"

trap 'echo; echo "[INFO]  停止 ..."; kill $PID 2>/dev/null || true; wait $PID 2>/dev/null || true; echo "[OK]    已停止"; exit 0' INT TERM
wait "$PID"