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

DEV_MODE="${DEV_MODE:-false}"

MAIN_HOST="${HOST:-0.0.0.0}"
MAIN_PORT="${PORT:-7860}"

MODEL_HOST="${MODEL_HOST:-0.0.0.0}"
MODEL_PORT="${MODEL_PORT:-8001}"

TAILWIND_BIN="/app/bin/tailwindcss"
TAILWIND_IN="/app/public/styles/input.css"
TAILWIND_OUT="/app/public/styles/output.css"

log() { printf "%s %s\n" "$(date +'%Y-%m-%dT%H:%M:%S%z')" "$*"; }

ensure_tailwind() {
  if [[ -x "${TAILWIND_BIN}" ]]; then
    log "Tailwind CSS found at ${TAILWIND_BIN}"
    return
  fi

  log "Tailwind CSS not found, downloading binary..."
  mkdir -p /app/bin

  local os arch
  os="$(uname -s | tr '[:upper:]' '[:lower:]')"
  arch="$(uname -m)"

  case "${os}" in
    darwin) os="macos" ;;
    linux)  os="linux" ;;
    *)      log "Unsupported OS: ${os}"; exit 1 ;;
  esac

  case "${arch}" in
    x86_64|amd64) arch="x64" ;;
    arm64|aarch64) arch="arm64" ;;
    *)      log "Unsupported arch: ${arch}"; exit 1 ;;
  esac

  curl -sSLo "${TAILWIND_BIN}" \
    "https://github.com/tailwindlabs/tailwindcss/releases/latest/download/tailwindcss-${os}-${arch}"
  chmod +x "${TAILWIND_BIN}"
}

build_tailwind() {
  if [[ "${DEV_MODE}" == "true" ]]; then
    log "Building Tailwind (initial)..."
    "${TAILWIND_BIN}" -i "${TAILWIND_IN}" -o "${TAILWIND_OUT}"
    log "Starting Tailwind in watch mode (dev)..."
    "${TAILWIND_BIN}" -i "${TAILWIND_IN}" -o "${TAILWIND_OUT}" --watch=always --poll &
    export TAILWIND_PID=$!
  else
    log "Building Tailwind (prod)..."
    "${TAILWIND_BIN}" -i "${TAILWIND_IN}" -o "${TAILWIND_OUT}" --minify
  fi
}

download_dataset() {

    if ! PYTHONPATH=/app poetry run python /app/scripts/download_dataset.py; then
      log "WARN: dataset download failed; continuing without cached dataset."
    fi
}

start_model_server() {

  if [[ "${DEV_MODE}" == "true" ]]; then
    log "DEV mode: NOT starting model server. Open VS Code and press F5 (Run and Debug) to launch it."
    return 0
  fi

  if [[ -n "${MODEL__ITEM_MODEL_PATH:-}" || -n "${MODEL__SCALE_MODEL_PATH:-}" ]]; then
    log "Starting model server on ${MODEL_HOST}:${MODEL_PORT}..."

    poetry run uvicorn src.servers.model_server:app \
      --host "${MODEL_HOST}" \
      --port "${MODEL_PORT}" \
      --workers "${MODEL_WORKERS:-1}" &
    export MODEL_PID=$!
  else
    log "Model paths not configured — NOT starting model server."
  fi
}

start_main_app() {
  if [[ "${DEV_MODE}" == "true" ]]; then
    log "DEV mode: NOT starting main FastAPI app. Open VS Code and press F5 (Run and Debug) to launch it."
    return 0
  fi

  log "PROD mode: starting Gunicorn (Uvicorn worker) on ${MAIN_HOST}:${MAIN_PORT}..."
  exec poetry run gunicorn src.main:app \
    -k uvicorn.workers.UvicornWorker \
    -w "${WEB_CONCURRENCY:-2}" \
    -b "${MAIN_HOST}:${MAIN_PORT}"
}

cleanup() {
  log "Shutting down..."

  if [[ -n "${TAILWIND_PID:-}" ]]; then
    log "Stopping Tailwind (PID ${TAILWIND_PID})"
    kill "${TAILWIND_PID}" 2>/dev/null || true
  fi
  if [[ -n "${MODEL_PID:-}" ]]; then
    log "Stopping model server (PID ${MODEL_PID})"
    kill "${MODEL_PID}" 2>/dev/null || true
  fi
}

trap cleanup SIGINT SIGTERM

if [[ "${DEV_MODE}" == "true" ]]; then
  log "Starting services in DEVELOPMENT mode..."
else
  log "Starting services in PRODUCTION mode..."
fi

ensure_tailwind
download_dataset
build_tailwind
start_model_server
start_main_app

if [[ "${DEV_MODE}" == "true" ]]; then
  log "Dev services running. Press Ctrl+C to stop."
  wait
fi