#!/usr/bin/env bash
# ------------------------------------------------------------------
# 12_start_server_122b_background.sh
# Launches the vLLM server for Qwen3.5-122B-A10B-FP8 in background.
#
# NOTE: Only one model can run on port 7080 at a time.
#       Stop the current model first:  bash 05_stop_server.sh
#
# Usage:
#   bash 12_start_server_122b_background.sh
#
# Logs are written to: ./logs/vllm_server_122b_<timestamp>.log
# PID is written to:   ./logs/vllm_server.pid
# ------------------------------------------------------------------
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
LOG_DIR="${SCRIPT_DIR}/logs"
mkdir -p "$LOG_DIR"

TIMESTAMP="$(date +%Y%m%d_%H%M%S)"
LOG_FILE="${LOG_DIR}/vllm_server_122b_${TIMESTAMP}.log"
PID_FILE="${LOG_DIR}/vllm_server.pid"

if [ -f "$PID_FILE" ]; then
    OLD_PID=$(cat "$PID_FILE")
    if kill -0 "$OLD_PID" 2>/dev/null; then
        echo "A vLLM server is already running with PID ${OLD_PID}"
        echo "Stop it first:  bash 05_stop_server.sh"
        exit 1
    fi
fi

echo "Starting vLLM server (122B) in background..."
echo "Log file: ${LOG_FILE}"

nohup bash "${SCRIPT_DIR}/11_start_server_122b.sh" > "$LOG_FILE" 2>&1 &
SERVER_PID=$!
echo "$SERVER_PID" > "$PID_FILE"

echo "Server PID: ${SERVER_PID}"
echo ""
echo "Monitor logs:    tail -f ${LOG_FILE}"
echo "Stop server:     bash 05_stop_server.sh"
echo ""

sleep 3
if kill -0 "$SERVER_PID" 2>/dev/null; then
    echo "Server process is running. Waiting for model to load..."
    echo "(This can take 5-10 minutes for Qwen3.5-122B-A10B-FP8)"
else
    echo "ERROR: Server process exited. Check logs:"
    tail -20 "$LOG_FILE"
    exit 1
fi